[Federal Register Volume 66, Number 95 (Wednesday, May 16, 2001)]
[Rules and Regulations]
[Pages 27266-27297]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 01-11411]


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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Parts 261 and 268

[FRL-6975-2]
RIN 2050-AE07


Hazardous Waste Identification Rule (HWIR): Revisions to the 
Mixture and Derived-From Rules

AGENCY: Environmental Protection Agency (EPA).

ACTION: Final rule.

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SUMMARY: Today's action finalizes the retention of the mixture rule and 
the derived-from rule in the Resource Conservation and Recovery Act 
(RCRA), with two revisions. The mixture and derived-from rules ensure 
that hazardous wastes that are mixed with other wastes or that result 
from the treatment, storage or disposal of hazardous wastes do not 
escape regulation and thereby cause harm to human health and the 
environment.
    EPA is finalizing two revisions to the mixture and derived-from 
rules. These revisions would narrow the scope of the mixture and 
derived-from rules, tailoring the rules to more specifically match the 
risks posed by particular wastes. The first revision is an expanded 
exclusion for mixtures and/or derivatives of wastes listed solely for 
the ignitability, corrosivity, and/or reactivity characteristics. The 
second revision is a new conditional exemption from the mixture and 
derived-from rules for ``mixed wastes'' (that is, wastes that are both 
hazardous and radioactive).

DATES: These final regulations are effective on August 14, 2001.

ADDRESSES: Supporting materials are available for viewing in the RCRA 
Information Center (RIC), located at Crystal Gateway I, First Floor, 
1235 Jefferson Davis Highway, Arlington, VA. The Docket Identification 
Number is F-2001-WHWF-FFFFF. The RIC is open from 9 a.m. to 4 p.m., 
Monday through Friday, excluding federal holidays. To review docket 
materials, it is recommended that the public make an appointment by 
calling 703 603-9230. The public may copy a maximum of 100 pages from 
any regulatory docket at no charge. Additional copies cost $0.15/page. 
The index and some supporting materials are available electronically. 
See the ``Supplementary Information'' section for information on 
accessing them.

FOR FURTHER INFORMATION CONTACT: For general information, contact the 
RCRA Hotline at 800 424-9346 or TDD 800 553-7672 (hearing impaired). In 
the Washington, DC, metropolitan area, call 703 412-9810 or TDD 703 
412-3323.
    For more detailed information on specific aspects of this 
rulemaking, contact Tracy Atagi, Office of Solid Waste 5304W, U.S. 
Environmental Protection Agency, 1200 Pennsylvania Avenue, NW., 
Washington, DC 20460-0002, 703-308-8672, [email protected].

SUPPLEMENTARY INFORMATION: The index and many of the supporting 
materials are available on the Internet. You can find these materials 
at http://www.epa.gov/epaoswer/hazwaste/id/hwirwste/index.htm>.

Affected Entities

    Entities potentially affected by this action are generators of 
industrial hazardous waste, and entities that treat, store, transport 
and/or dispose of these wastes. This table is not intended to be 
exhaustive, but rather provides a guide for readers regarding entities 
likely to be affected by this action.

------------------------------------------------------------------------
                                                            List of
                                                          potentially
            SIC code                  NAICS code          affected US
                                                          Industrial
                                                           Entities
------------------------------------------------------------------------
         Revision to 40 CFR 261.3 Definition of hazardous waste
------------------------------------------------------------------------
2800............................  32xxxx............  Chemicals & allied
                                                       products
                                                       manufacturing.
2819............................  Five possible       Industrial
                                   codes.              inorganic
                                                       chemicals
                                                       manufacturing.
2821............................  325211............  Plastics materials
                                                       & resins
                                                       manufacturing.
2833............................  325411............  Medicinal
                                                       chemicals &
                                                       botanicals
                                                       manufacturing.
2834............................  325412............  Pharmaceutical
                                                       preparations
                                                       manufacturing.
2851............................  32551.............  Paints & allied
                                                       manufacturing.
2869............................  Five possible       Industrial organic
                                   codes.              chemicals
                                                       manufacturing.
2879............................  32532.............  Pesticides &
                                                       agricultural
                                                       chemicals
                                                       manufacturing.
3089............................  Four possible       Plastics products
                                   codes.              manufacturing.
3241............................  32731.............  Hydraulic cement
                                                       products
                                                       manufacturing.
3479............................  Four possible       Fabricated metal
                                   codes.              coating & allied
                                                       services
3711............................  Five possible       Motor vehicle &
                                   codes.              passenger car
                                                       bodies
                                                       manufacturing.
4212............................  562111 & 562112...  Local trucking
                                                       services
                                                       (industrial waste
                                                       shipment).
4953............................  Five possible       Refuse (industrial
                                   codes.              waste) treatment/
                                                       disposal
                                                       services.

[[Page 27267]]

 
7389............................  36 possible codes.  Business services.
7532............................  811121............  Auto repair & auto
                                                       paint shops.
9511............................  92411.............  Waste management.
9711............................  811121............  National security
                                                       (military bases).
 
------------------------------------------------------------------------
Explanatory Notes:
(1) SIC= 1987 Standard Industrial Classification system (US Department
  of Commerce's traditional code system last updated in 1987).
(2) NAICS= 1997 North American Industrial Classification System (US
  Department of Commerce's new code system as of 1997).
(3) Refer to the Internet website http://www.census.gov/epcd/www/naicsdev.htm for additional information and a cross-walk table for the
  SIC and NAICS codes systems.

    This table lists those entities that EPA believes could be affected 
by this action, based on industrial sectors identified in the economic 
analysis in support of this final rule. A total of about 120 entities 
are expected to benefit from the proposed revisions to 40 CFR 261.3 in 
the 17 industrial sectors listed above, but primarily in the chemicals 
and allied products sector (i.e., SIC code 28, or NAICS code 325). 
Other entities not listed in the table also could be affected. To 
determine whether your facility is regulated by this action, you should 
examine 40 CFR parts 260, 261 and 268 carefully in concert with the 
amended rules found at the end of this Federal Register document. If 
you have questions regarding the applicability of this action to a 
particular entity, consult the persons listed in the preceding FOR 
FURTHER INFORMATION CONTACT section.

                                Acronyms
------------------------------------------------------------------------
                Acronym                             Definition
------------------------------------------------------------------------
3MRA...................................  Multimedia, Multipathway and
                                          Multireceptor Risk Assessment
APA....................................  Administrative Procedures Act
BDAT...................................  Best Demonstrated Available
                                          Technology
CERCLA.................................  Comprehensive Environmental
                                          Response, Compensation and
                                          Liability Act
CFR....................................  Code of Federal Regulations
CMA....................................  Chemical Manufacturers
                                          Association
CWA....................................  Clean Water Act
DOT....................................  Department of Transportation
EPA....................................  Environmental Protection Agency
HSWA...................................  Hazardous and Solid Waste
                                          Amendments of 1984
HWIR...................................  Hazardous Waste Identification
                                          Rule
ICR....................................  Information Collection Request
IRIS...................................  Integrated Risk Information
                                          System
LDR....................................  Land Disposal Restriction
LLMW...................................  Low Level Mixed Wastes
LLRWDF.................................  Low Level Radioactive Waste
                                          Disposal Facility
MACT...................................  Maximum Achievable Control
                                          Technology
NPDES..................................  National Pollution Discharge
                                          Elimination System
NRC....................................  Nuclear Regulatory Commission
                                          (NRC)
NTTAA..................................  National Technology Transfer
                                          and Advancement Act
OMB....................................  Office of Management and Budget
ORD....................................  Office of Research and
                                          Development
OIRM...................................  Office of Information and
                                          Resources Management
OSW....................................  Office of Solid Waste
OSWER..................................  Office of Solid Waste and
                                          Emergency Response
PBMS...................................  Performance Based Measurement
                                          System
QA/QC..................................  Quality Assurance / Quality
                                          Control
RCRA...................................  Resource Conservation Recovery
                                          Act
RFA....................................  Regulatory Flexibility Act
RfD....................................  Reference Dose
RfC....................................  Reference Concentration
RIC....................................  RCRA Docket Information Center
SBREFA.................................  Small Business Regulatory
                                          Enforcement Fairness Act
TC.....................................  Toxicity Characteristic
TCLP...................................  Toxicity Characteristic
                                          Leaching Procedure
TDD....................................  Telecommunications Device for
                                          the Deaf
TSDF...................................  Treatment, Storage, and
                                          Disposal Facility
UMRA...................................  Unfunded Mandates Reform Act
UTS....................................  Universal Treatment Standards
------------------------------------------------------------------------

Outline

Background

I. What law authorizes these rules?
II. Which hazardous waste identification rules is EPA finalizing 
today?
III. What is the legal history of these rules?
IV. How do the final rules compare to those proposed on November 19, 
1999?
V. When will the final rules become effective?
VI. What other changes to the hazardous waste identification rules 
is EPA continuing to pursue?

[[Page 27268]]

Major Comments

VII. What were the major comments on retaining the mixture and 
derived-from rules, and how has EPA responded to them?
    A. Need for the mixture and derived-from rules
    B. Legality of the mixture and derived-from rules
    C. Regulatory cost of the mixture and derived-from rules
VIII. What were the major comments on the revision to 40 CFR 261.3 
to exclude wastes listed solely for ignitability, corrosivity, and/
or reactivity, and how has EPA responded to them?
    A. Eligibility of waste listed for the toxicity characteristic
    B. Toxicity of wastes listed for ignitability, corrosivity, and/
or reactivity
    C. Eligibility of F003 solvents for this exclusion
    D. Applicability of Land Disposal Restrictions (LDRs) to 
excluded wastes
    E. Applicability of contained-in policy to excluded wastes
IX. What were the major comments on the revision to 40 CFR 261.3 for 
mixed wastes, and how has EPA responded to them?
X. What were the major comments on the proposals submitted by the 
Chemical Manufacturers Association (CMA), and how has EPA responded 
to them?
    A. Expanding the current headworks exclusion
    B. Excluding hazardous waste leachate
    C. Excluding hazardous waste aggressive biological treatment 
residues
    D. Excluding hazardous waste combustion residues
    E. Expanding the current de minimis exclusion

State Authorization

XI. How will today's regulatory changes be administered and enforced 
in the States?

Administrative Requirements

XII. How has EPA fulfilled the administrative requirements for this 
rulemaking?
    A. Executive Order 12866: Determination of Significance
    B. Regulatory Flexibility Act
    C. Paperwork Reduction Act (Information Collection Request)
    D. Unfunded Mandates Reform Act
    E. Executive Order 13132: Federalism
    F. Executive Order 13175: Consultation and Coordination with 
Indian Tribal Governments
    G. Executive Order 13045: Protection of Children from 
Environmental Health Risks and Safety Risks
    H. National Technology Transfer and Advancement Act of 1995
    I. Executive Order 12898: Environmental Justice
    J. Congressional Review Act

Technical Correction

XIII. What technical correction is EPA making in today's rulemaking?

Background

I. What Law Authorizes These Rules?

    These rules are promulgated under the authority of Sections 
2002(a), 3001, 3002, 3004, and 3006 of the Solid Waste Disposal Act of 
1970, as amended by the Resource Conservation and Recovery Act of 1976 
(RCRA), as amended by the Hazardous and Solid Waste Amendments of 1984 
(HSWA), 42 U.S.C. 6912(a), 6921, 6922, 6924, 6926.

II. Which Hazardous Waste Identification Rules Is EPA Finalizing 
Today?

    Today, EPA is finalizing retention and revision of the mixture and 
derived-from rules, previously set forth in 40 CFR 261.3(a)(2)(iii), 
261.3(a)(2)(iv) and 261.3(c)(2)(i), and proposed at 64 FR 63382 
(November 19, 1999). The mixture and derived-from rules are a part of 
the RCRA rules that define which wastes are considered to be hazardous 
and therefore subject to RCRA Subtitle C rules. The mixture and 
derived-from rules identify as hazardous those wastes that originate 
from RCRA hazardous waste listed under 40 CFR part 261 (referred to as 
``listed hazardous wastes''). Under the mixture rule, a mixture of a 
solid waste with one or more listed hazardous wastes is a hazardous 
waste. Under the derived-from rule, any solid waste generated from the 
treatment, storage, or disposal of a listed hazardous waste remains 
regulated as a hazardous waste. These derived-from wastes include 
wastes such as sludges, spill residues, ash, emission control dust, and 
leachate generated from listed hazardous wastes.
    The mixture and derived-from rules that are being finalized today 
include two revisions to these rules. For the first revision, we have 
narrowed the applicability of the derived-from rules by excluding 
derivatives of wastes listed solely for the characteristics of 
ignitability, reactivity, and/or corrosivity when they no longer 
exhibit any characteristic of hazardous waste. Mixtures of wastes 
listed solely for the characteristic of ignitability, reactivity, and/
or corrosivity which no longer exhibit any characteristic of hazardous 
waste continue to be excluded under today's rules. In summary, under 
today's final rules, all wastes listed solely for an ignitability, 
reactivity and/or corrosivity characteristic (including mixtures, 
derived-from and as generated wastes) are excluded once they no longer 
exhibit a characteristic.
    For the second revision, we are also finalizing a conditional 
exemption for certain low-level mixed waste (i.e., waste that is both 
radioactive and hazardous) from the mixture and derived-from rules, 
provided the mixed waste is handled in accordance with 40 CFR part 266, 
Subpart N. This Subpart, which is being published as a final rule 
elsewhere in today's Federal Register, explains the eligibility 
requirements for this exemption, and includes several conditions and 
requirements for the exempted waste.

III. What Is the Legal History of These Rules?

    EPA promulgated the mixture and derived-from rules in 1980 as part 
of the comprehensive ``cradle to grave'' requirements for managing 
hazardous waste. 45 FR 33066 (May 19, 1980). Numerous industries that 
generate hazardous wastes challenged the 1980 mixture and derived-from 
rules. In December 1991, the D.C. Circuit Court of Appeals vacated the 
rules because they had been promulgated without adequate notice and 
opportunity to comment. Shell Oil Co. v. EPA, 950 F. 2d 741 (D.C. Cir. 
1991). The court, however, suggested that EPA might want to consider 
reinstating the rules pending full notice and comment in order to 
ensure continued protection of human health and the environment.
    In response to this decision, we promulgated an emergency rule 
reinstating the mixture and derived-from rules as interim final rules 
without providing notice and opportunity to comment. 57 FR 7628 (March 
3, 1992). We also promulgated a ``sunset provision'' which provided 
that the mixture and derived-from rules would remain in effect only 
until April 28, 1993. Shortly after, we published a proposal containing 
several options for revising the mixture and derived-from rules. See 57 
FR 21450 (May 20, 1992). The May 1992 proposal and the time pressure 
created by the ``sunset provision'' generated significant controversy. 
In response, Congress included in EPA's fiscal year (FY) 1993 
appropriation several provisions addressing the mixture and derived-
from rules. Public Law No. 102-389, 106 Stat. 1571. First, Congress 
nullified the sunset provision by providing that EPA could not 
promulgate any revisions to the rules before October 1, 1993, and by 
providing that the reinstated regulations could not be ``terminated or 
withdrawn'' until revisions took effect. However, to ensure that we 
could not postpone the issue of revisions indefinitely, Congress also 
established a deadline of October 1, 1994 for the promulgation of 
revisions to the mixture and derived-from rules. Congress made this 
deadline enforceable under RCRA's citizen suit provision, section 7002.

[[Page 27269]]

    On October 30, 1992, we published two notices, one removing the 
sunset provision, and the other withdrawing the May 1992 proposal. (See 
57 FR 49278, 49280). We had received many comments criticizing the May 
1992 proposal. The criticisms were due, in a large part, to the very 
short schedule imposed on the regulation development process itself. 
Commenters also feared that the proposal would result in a 
``patchwork'' of differing State programs because some states might not 
adopt the revisions. This fear was based on the belief that States 
would react in a negative manner to the proposal and refuse to 
incorporate it into their programs if finalized. Finally, many 
commenters also argued that the risk assessment used to support the 
proposed exemption levels failed to provide adequate protection of 
human health and the environment because it evaluated only the risks of 
human consumption of contaminated groundwater and ignored other 
pathways that could pose greater risks. Based on these concerns, and 
based on EPA's desire to work through the individual elements of the 
proposal more carefully, we withdrew the proposal.
    Subsequently, a group of waste generating industries challenged the 
March 1992 action that reinstated the mixture and derived-from rules 
without change. Mobil Oil Corp. v. EPA, 35 F.3d 579 (D.C. Cir. 1994). 
The court rejected this challenge, holding that the fiscal year (FY) 
1993 appropriations act made the challenge moot because it prevented 
both us and the courts from terminating or withdrawing the interim 
rules before we revised them, even if we failed to meet the statutory 
deadline for the revisions.
    We did not meet Congress' October 1, 1994 deadline for revising the 
mixture and derived-from rules. In early October 1994, several groups 
of waste generating and waste managing industries filed citizen suits 
to enforce the October 1 deadline for revising the mixture and derived-
from rules. Two of the cases were consolidated and a third was 
dismissed with the plaintiffs being added as intervenor to the 
consolidated cases. Environmental Technology Council v. Browner, C.A. 
No. 94-2119, 94-2436 (TFH) (D.D.C.). The U.S. District Court for the 
District of Columbia entered a consent decree resolving the 
consolidated cases. The consent decree, as subsequently amended, 
required the Administrator to sign a proposal to revise the mixture and 
derived-from rules by November 13, 1995 and a notice of final action on 
the proposal by February 13, 1997, and it also specified that the 
deadlines in the 1992 appropriations act do not apply to any rule 
revising the separate regulations that establish jurisdiction over 
media contaminated with hazardous wastes. On November 13, 1995, the 
Administrator signed the proposed Hazardous Waste Identification Rule 
to revise the mixture and derived-from rules, which was published in 
the Federal Register on December 21, 1995. (60 FR 66344). It proposed a 
set of exemption levels for hundreds of hazardous constituents, many of 
which were based on a complex multipathway risk assessment. The notice 
also proposed to revise the derived-from rule to exclude wastes listed 
because they exhibited the characteristics of ignitability, corrosivity 
and/or reactivity from the definition of hazardous waste, and solicited 
comment on the concept of providing a separate exemption for hazardous 
wastes mixed with low level radioactive wastes.
    We received extensive comments, many critical, on the 1995 
proposal, particularly with respect to the scientific risk assessment 
supporting the proposed concentration-based exemption from the mixture 
and derived-from rules. As a result of the comments, we concluded that 
considerable work needed to be done to resolve the complex scientific 
and technical issues raised. On April 11, 1997, the District Court 
entered an order amending the consent decree in Environmental 
Technology Council v. Browner. The amended decree provided us with 
additional time to perform further scientific risk assessment work and 
required us to ask for comment on specific issues. On November 19, 
1999, we published a proposal requesting comment on revisions to the 
mixture and derived-from rules, and discussed and requested comment on 
the issues specified in the consent decree. Today's final rulemaking 
completes our legal obligation regarding revisions to the mixture and 
derived-from rules.

IV. How Do the Final Rules Compare to Those Proposed on November 
19, 1999?

    As we proposed, we are retaining both the mixture and derived-from 
rules, and the revisions to those rules that we are finalizing today 
are for the most part the same as those we proposed in November 1999. 
Our rationale and basis for today's final rulemaking is set forth in 
Sections VII, VIII, and IX of this preamble.
    The first revision amends the regulations under 40 CFR 261.3 for 
wastes listed in 40 CFR part 261, subpart D solely because they exhibit 
a characteristic of hazardous waste. Under current regulations, such 
listed wastes as generated or treated are considered hazardous under 
RCRA Subtitle C, even when the waste does not exhibit a characteristic, 
unless they are delisted. However, mixtures are considered non-
hazardous if the waste no longer exhibits any characteristic.
    In the November 19, 1999 notice, we proposed to amend the scope of 
and expand the applicability of the current exclusion. The notice 
proposed a clarifying change to the scope of the exclusion to include 
those wastes listed in part 261, subpart D only for a characteristic of 
ignitability corrosivity, or reactivity. The notice also proposed to 
expand the applicability of the exclusion so all these materials would 
be excluded from hazardous waste regulation if they are decharacterized 
and meet the appropriate treatment standards. The notice stated that 
most of the currently regulated waste eligible for this exclusion is 
listed as F003, but would also include certain K-, P- and U-listed 
wastes (See 64 FR 63390-63391, November 19, 1999).
    The exclusion applies when a generator determines that the waste, 
whether as generated or after treatment, does not exhibit any 
characteristic. This exclusion is self implementing, with no additional 
recordkeeping and reporting requirements.\1\ EPA is finalizing this 
exclusion as it was proposed. With respect to the applicability of land 
disposal restrictions (LDR) in Part 268, EPA is clarifying that when a 
waste has been listed solely because it exhibits a characteristic of 
ignitability, corrosivity, and/or reactivity AND that waste does not 
exhibit any hazardous waste characteristic at the point of generation, 
then that waste is not subject to the LDR requirements. Wastes that are 
characteristic at the point of generation and then are subsequently 
decharacterized are still subject to LDR requirements. For information 
on the major public comments and EPA's responses and rationale for this 
exclusion, please see Section VIII of this preamble. For discussion of 
the LDR issue in particular, please see Section VIII.D.
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    \1\ However, under 40 CFR 268.7(a)(7)(a) generator must still 
put a one-time notification in the facility files describing the 
waste generation, regulatory exclusion, and disposition of the 
waste(s). According to 40 CFR 268.7(a)(8), this notification must be 
kept for at least three years.
---------------------------------------------------------------------------

    The second revision to the mixture and derived-from rules involves 
mixed waste (i.e., wastes that are both hazardous and radioactive). 
Under this revision, mixed waste is conditionally exempt from the 
mixture and derived-from rules, provided the mixed waste is

[[Page 27270]]

handled in accordance with 40 CFR part 266, Subpart N.
    The regulatory language in 40 CFR part 266, Subpart N, which we are 
promulgating in a separate final rule published elsewhere today, 
conditionally exempts hazardous waste mixed with low-level radioactive 
wastes (low-level mixed wastes/LLMW) from the storage, treatment in 
tank, transportation, and disposal requirements of RCRA. In addition, 
hazardous waste mixed with Naturally Occurring and/or Accelerator-
produced Radioactive Material (NARM mixed waste) can be exempted from 
transportation and disposal requirements. The Nuclear Regulatory 
Commission (NRC) or its Agreement State licensed LLMW generators can 
store, or treat LLMW in storage tanks without RCRA Subtitle C permits 
if all exemption conditions are met. Treated LLMW or NARM mixed waste 
could be disposed at a low level radioactive waste disposal facility 
(LLRWDF) regulated by the NRC or its Agreement State if all exemption 
conditions are met. The rationale for conditionally exempting LLMW from 
the mixture and derived-from rules is the same as that for creating the 
conditional exemption from the RCRA regulatory definition of hazardous 
waste for LLMW.
    We are largely finalizing the mixed waste exemption from the 
mixture and derived-from rules as proposed. However, to address public 
comments on the need for more clarity of this exemption, we have 
revised the regulatory language and have moved it to its own subsection 
(40 CFR 261.3(h)). As used in section 261.3(h), the term ``eligible 
radioactive mixed waste'' refers to hazardous waste containing 
radioactive waste that meets the eligibility criteria and conditions of 
part 266, subpart N. In addition, we have made some changes to the new 
Subpart N from what we proposed. Those changes are explained in the 
mixed waste final rule, published elsewhere in the Federal Register 
today. For information on the public comment regarding the exemption, 
and EPA's responses please see Section IX of this preamble.

V. When Will the Final Rules Become Effective?

    Today's rules become effective August 14, 2001. Pursuant to section 
3010(b)(1) of RCRA, the Administrator finds that the regulated 
community does not need six months to come into compliance with today's 
rulemaking, because today's action retains rules already in effect, and 
expands an exclusion that reduces regulatory burden.

VI. What Other Changes to the Hazardous Waste Identification Rules 
Is EPA Continuing To Pursue?

    EPA continues to pursue an exemption from hazardous waste 
management that we discussed in the November 19, 1999 HWIR Federal 
Register notice (64 FR 63382). That exemption, also known as the 
Hazardous Waste Identification Rule (HWIR) exemption, would exempt 
listed hazardous wastes that meet chemical-specific exemption levels 
\2\ from the definition of hazardous waste. The HWIR exemption would 
help address concerns that the mixture and derived-from rules result in 
over-regulation, since listed hazardous waste remains under Subtitle C 
jurisdiction regardless of constituent concentration or presence in the 
waste, either before or after treatment. This concern was exacerbated 
with the passage of HSWA in 1984. HSWA set Land Disposal Restrictions 
(LDR) requiring best demonstrated available technology (BDAT) treatment 
for all listed hazardous wastes prior to disposal. In cases where a 
specific listed wastestream contained relatively innocuous 
constituents, or very low concentrations, BDAT treatment requirements 
were felt to be overly protective, and unnecessarily expensive. The 
Agency believes that an HWIR exemption process would help reduce the 
potential over-regulation of low risk hazardous waste while, at the 
same time, reducing the time and resource burden on industry and 
government. An exemption process would also reduce the burden on the 
ongoing delisting program. In the 1995 HWIR proposal, we estimated cost 
savings ranging from $75 million to $99 million, based on exemption 
levels proposed at that time. Given that the modeling for exemption 
levels is undergoing major revision, it is not possible at this time to 
estimate the cost savings from a future constituent-based exemption.
---------------------------------------------------------------------------

    \2\ An ``exemption level'' in this context is a specific 
chemical concentration. If all chemicals in a waste are below their 
exemption levels, then the waste would be considered non-hazardous.
---------------------------------------------------------------------------

    We plan to develop the HWIR exemption levels based on results from 
the Multi-media, Multi-pathway and Multi-receptor risk assessment 
(3MRA) Model. The model evaluates simultaneous chemical exposures 
across several environmental media and multiple exposure pathways to 
human and ecological receptors in order to estimate the health and 
ecological effects in the vicinity of waste disposal units that may 
receive exempt listed hazardous waste. We presented the underlying 
methodology and assumptions for the 3MRA Model in the Federal Register 
(64 FR 63382, November 19, 1999). However, because of technical 
difficulties arising from the complexity of the modeling effort, we 
were unable to propose exemption levels in that notice. Since then, we 
have made numerous revisions to correct and improve the model.
    On July 18, 2000, EPA made available in a Notice of Data 
Availability (NODA) the model results for 36 chemicals, using an 
updated version of the model (65 FR 44491). The NODA, and referenced 
background information placed in the docket, explained technical 
changes made to the model since the November 19, 1999 Federal Register 
notice. Finally, the NODA extended the comment period for the November 
19, 1999 HWIR exemption discussion until October 16, 2000.
    We are currently reviewing the public comments and will decide if 
further revisions to the HWIR risk assessment (3MRA) model are 
necessary. We also are continuing independent testing and external peer 
review of the HWIR risk assessment model.
    In addition to the HWIR risk assessment, the November 19, 1999 
Federal Register notice discussed options for implementing the HWIR 
exemption. We also plan to review the comments relating to 
implementation. Before using the revised risk assessment to support a 
final rulemaking on the HWIR exemption, we will publish a proposal to 
allow public comment on a unified package.
    In another effort to better calibrate risk and regulatory 
standards, the Agency is also developing two targeted exemptions from 
the hazardous waste mixture and derived-from rules: one for certain 
solvents destined for wastewater treatment and discharge under the 
Clean Water Act, and another for slagged combustion residues from 
hazardous waste combustors. Other targeted exemptions are being 
assessed for later development (see Section X of this preamble for 
further discussion). We also plan to continue on-going efforts to 
streamline the existing delisting process.

Major Comments

VII. What Were the Major Comments on Retaining the Mixture and 
Derived-From Rules, and How Has EPA Responded to Them?

    EPA received several dozen comments on the issue of retaining the 
mixture and derived-rules for both the 1995 and 1999 HWIR proposals. 
Below is a summary of three major issue areas

[[Page 27271]]

raised in the comments, and EPA's responses. For more detailed comment 
responses, please see Hazardous Waste Identification Rule: Revisions to 
the Mixture and Derived-From Rules Response to Comments Document.

A. Need for the Mixture and Derived-From Rules

(1)(a) Summary of the Comments on the Need for the Mixture and Derived-
From Rules
    EPA received comments from 38 commenters in response to both the 
1995 and the 1999 HWIR proposals specifically concerning the necessity 
of the mixture and derived-from rules. Of those comments, 14 were 
received from industry, seven were from industry associations, eight 
were from State Agencies, five were from waste management companies, 
two were from waste management associations, one was from a Federal 
Agency and one was from a consultant.
    The States and waste management associations supported the 
retention of the mixture and derived-from rules, while the industry 
commenters generally believed that the mixture and derived-from rules 
were unnecessary. A summary of the specific issues raised by commenters 
is provided below.
    Twelve commenters explicitly supported the retention of the mixture 
and derived-from rules. Many of the State commenters said that the 
rules were necessary to capture mixtures and derivatives of listed 
hazardous wastes in the universe of regulated hazardous wastes in order 
to protect human health and the environment. The commenters noted that 
without these rules, it would be possible to alter a particular waste 
to the point that it no longer meets the listing description without 
detoxifying, immobilizing, or otherwise actually treating the waste. 
One industry association commenter also supported the retention of the 
mixture and derived-from rules, noting that although it is not a 
perfect solution, the approach has been used for the last 15 years in a 
generally effective manner.
    One waste management association commenter also strongly supported 
the retention of the mixture and derived-from rules. The commenter 
believed the mixture and derived-from rules were necessary because they 
prevented many wastes that clearly were hazardous and that posed 
substantial threats to human health and the environment from escaping 
RCRA controls only because they are mixtures or derivatives that no 
longer fit an original listing description. The commenter noted that 
generators send their listed hazardous wastes to treatment facilities 
for initial treatment to reduce the toxicity and/or mobility of some, 
but not all, toxic constituents in the waste. The commenter also agreed 
that EPA's experience with delisting petitions further supported the 
rationale for the mixture and derived-from rules.
    Twenty-six commenters did not support the retention of the mixture 
and derived-from rules. Some asserted that eliminating the derived-from 
rule would be a common sense reform of RCRA to reduce unnecessary over-
regulation of many wastes. Many industry commenters and industry 
associations commented that the mixture and derived-from rules 
unnecessarily continue to regulate low-risk material resulting in 
significant waste management costs with no associated environmental 
benefit, thus also affecting the credibility of EPA. Several of the 
comments cited EPA's 1992 HWIR proposal, saying that ``millions of tons 
of mixtures and derived-from residuals that must be managed as 
hazardous waste * * * may actually pose quite low hazards.'' (57 FR 
21451, May 20, 1992). The Department of Defense acknowledged the need 
to retain the mixture and derived-from rules; however, the commenter 
noted that the mixture and derived-from rules have been a source of 
over-regulation for low-risk wastes.
    Several commenters asserted that the mixture and derived-from rules 
have no continued viability, particularly in light of the technological 
advances that have developed since the rules were first promulgated in 
1980. They noted that since 1980, the regulated community has made 
considerable improvements in the treatment, storage, and disposal of 
hazardous waste. In their view, the result is that the risks that 
formerly may have been associated with the management of hazardous 
waste have been reduced significantly or eliminated, such that the 
universe of waste that may have warranted Subtitle C regulation in 1980 
has been reduced significantly. Six commenters agreed with the U.S. 
Court of Appeals observation in Shell Oil Co. v. EPA, 590 F.2d 741, 752 
(D.C. Cir. 1991) that, ``the derived-from rule becomes counterintuitive 
as applied to processes designed to render wastes nonhazardous. Rather 
than presuming that these processes will achieve their goals, the 
derived-from rule assumes their failure.'' Commenters also noted that 
the hazardous waste characteristics, particularly the Toxicity 
Characteristic, would continue to ensure proper management of high risk 
wastes under RCRA.
    Several commenters stated that when compared to established 
standards, a waste material is either hazardous or it is not and it is 
not necessary to consider the origin of the material. The consultant 
noted that the mixture rule is completely unnecessary and isn't 
scientifically appropriate because if the compound or element in the 
waste needs to be controlled in a certain environment, it doesn't 
matter what the source is. Therefore, a regulation should set the limit 
for that environment for that compound or element and the mixture and 
derived-from rules should be eliminated. One commenter believed that 
the continued inflexible application of the mixture and derived-from 
rules has served only to bring to light the self-defeating complexity 
of the program.
(1)(b) EPA Response To Comments on the Need for the Mixture and 
Derived-From Rules
    EPA acknowledges that the mixture and derived-from rules apply 
regardless of the concentrations and mobilities of hazardous 
constituents in the waste. We have implemented and will continue to 
pursue actions to reduce any overregulation of low-risk wastes arising 
from the mixture and derived-from rules. Nevertheless, EPA believes 
that retention of the mixture and derived-from rules are necessary to 
ensure protection of human health and the environment. When EPA 
determines that a waste should be listed as hazardous, we consider 
several different factors, including the toxicity of the chemicals in 
the waste, the persistence of those toxic chemicals, and the degree to 
which the chemicals bioaccumulate in the environment. As discussed 
below, the act of mixing a hazardous waste with another waste, or 
storing, treating, and disposing of that waste does not necessarily 
remove the hazard posed by these toxic chemicals. Under RCRA, EPA has 
an obligation to ensure that the risk posed by a hazardous waste is 
controlled from the cradle to the grave. Both the mixture and derived-
from rules are needed to make sure that this obligation is carried out.

Concerns About Deliberate Evasion

    When EPA originally promulgated the mixture and derived-from rules 
in 1980, one of our main concerns was that, without these rules, 
generators could deliberately evade regulation by taking advantage of a 
``loophole'' in the hazardous waste identification process. (45 FR 
33084, 33095 (May 19, 1980)). Specifically, we believed that without 
the mixture and derived-from rules, generators could potentially alter 
their waste so that it no longer meets the

[[Page 27272]]

listing description without detoxifying, immobilizing, or otherwise 
effectively treating the waste.
    Despite the progress that has been made in environmental compliance 
in the past twenty years, this concern remains, and the comments of 
EPA's co-regulators, the State governments, echo this continuing 
concern. EPA agrees with those industry comments that claim many 
companies are more environmentally aware and responsible than they were 
in the past. However, there will always be some entities who might try 
and exploit gaps in the regulatory system. Absent the mixture and 
derived-from rules, there would be a potentially significant gap in the 
coverage of the hazardous waste listings.
    For example, without a ``mixture'' rule, generators of hazardous 
wastes could potentially evade regulatory requirements by mixing listed 
hazardous wastes with other hazardous wastes or nonhazardous solid 
wastes to create a ``new'' waste that arguably no longer meets the 
listing description, but continues to pose a serious hazard. Similarly, 
without a ``derived-from'' rule, hazardous waste generators and 
hazardous waste treatment, storage, and disposal facilities (TSDFs) 
could potentially evade regulation by minimally processing or managing 
a hazardous waste and claiming that the resulting residue is no longer 
the listed waste, despite the continued hazards that could be posed by 
the residue even though it does not exhibit a characteristic. A 
hazardous waste regulatory system under which it could be argued that 
hazardous waste could leave the system as soon as it was modified to 
any degree by being mixed or marginally treated would be ineffective 
and unworkable. Such a system could act as a disincentive to adequately 
treat, store and dispose of listed hazardous waste.
    In addition, as explained below, even if generators or TSDFs do not 
deliberately try to evade hazardous waste regulations, certain waste 
mixtures and derived-from wastes could pose substantial present or 
potential hazards if mismanaged. We, therefore, continue to believe 
that the mixture and derived-from rules are necessary to capture wastes 
that would pose unacceptable risks to human health and the environment.

Regulating Hazardous Waste Mixtures

    Mixing hazardous waste with another waste may dilute, and sometimes 
mask, the concentrations of toxic constituents in the listed waste, but 
does not necessarily address the hazards posed by these constituents. 
Some of the comments focused on diluted wastewaters as an example of 
mixtures that are potentially ``low risk.'' Of the ``millions of tons'' 
of waste that EPA estimated would be exempted under the 1995 HWIR 
proposal because they may pose low risks, 99% of the waste by volume is 
wastewater (60 FR 66415, December 21, 1995). Wastewaters are generally 
disposed either in an underground injection control well regulated 
under the Safe Drinking Water Act (SDWA)or to the environment under the 
Clean Water Act (CWA). Because discharged hazardous wastewaters must 
meet CWA standards, some commenters believe that these wastewater 
mixtures should be excluded from hazardous waste regulation prior to 
their discharge.
    We have several concerns with this argument. The management of 
wastewater mixtures is already largely exempt from most RCRA 
requirements. The two main requirements that remain under RCRA are that 
the wastewaters must be managed in tanks, and the treatment sludge must 
be managed as a hazardous waste once removed from the tank. Continued 
management of these wastewaters in tanks is usually needed to avoid 
infiltration to groundwater of concentrations of toxic constituents 
that pose unacceptable risks. Even when they meet their CWA discharge 
limits, mismanaged wastes could pose unacceptable risks through the 
groundwater pathway, which is not addressed by the CWA. Sludges from 
wastewater treatment need to be managed as hazardous waste, because 
they can contain the same persistent and toxic chemicals (e.g., heavy 
metals) that originated in the wastewaters. Each of these points is 
discussed in more detail below.
    RCRA section 1004(27) already excludes industrial wastewater 
discharges subject to CWA section 402 regulation from the definition of 
``solid waste'' under RCRA. See also, 40 CFR 261.4(a)(2). In addition, 
wastewater treatment units, as defined in 40 CFR 260.10 (i.e., tanks), 
are excluded from almost all RCRA regulation (see 40 CFR 264.1(g)(6); 
265.1(c)(10); and 270.1(c)(2)(v)). RCRA has historically deferred to 
the Clean Water Act and its oversight in properly regulating hazardous 
wastewaters discharged by CWA wastewater treatment systems or other 
point sources subject to CWA discharge requirements, including storage 
in wastewater treatment units prior to discharge. However, with the 
exception of sewage sludge, the CWA does not apply to sludges which are 
a byproduct of wastewater treatment. To the extent treatment of listed 
hazardous wastewaters generates sludges, those sludges are considered 
hazardous by the derived-from rule (as discussed below).
    Furthermore, to the extent that additional hazards may be 
associated with wastewaters managed in such systems (including risks 
via inhalation pathway and risks via groundwater ingestion when 
treatment takes place in surface impoundments),\3\ the Agency considers 
such wastes as hazardous and within RCRA jurisdiction until discharged. 
While wastewaters must meet CWA requirements at the point of discharge, 
they can still have high concentrations of constituents during the 
management of the waste.
---------------------------------------------------------------------------

    \3\ The Revised Air Characteristic Study (EPA 530-R-99-019a) 
published August 1999 suggests that potential risks emanating from 
wastewaters managed in wastewater treatment tanks may be of 
regulatory concern and may represent a regulatory gap because of the 
existing exclusions for wastewater treatment units from control 
requirements.
---------------------------------------------------------------------------

    Even after hazardous wastewaters have been treated to meet CWA 
standards, they could still have the potential to pose unacceptable 
risks to human health and the environment when managed in surface 
impoundments or other retention ponds (or otherwise managed on the 
land, i.e., during a spill) prior to discharge to the receiving water 
body. Both surface impoundments and retention ponds can have high 
potential for discharge of the wastewaters they contain to underlying 
groundwater (see RCRA sections 1002(b)(7) and 3005(j)). Discharge 
treatment requirements based on State water quality standards are 
calculated by taking the nature of the effluent and the receiving water 
body into account. An effluent treated to meet water quality standards 
for a surface water body could leach into groundwater, depending on the 
hydrogeology of the site, if subsequently held in a surface impoundment 
or retention pond prior to discharge. This leachate could undergo a 
lesser degree of dilution in groundwater than in the intended surface 
water body, potentially posing unacceptable risks to groundwater users 
through a drinking water well. This risk is not accounted for under the 
current federal CWA standards.\4\ Therefore, EPA continues to believe 
that retaining

[[Page 27273]]

jurisdiction over hazardous wastewaters under RCRA prior to their 
NPDES-permitted discharge is necessary to ensure protection of human 
health and the environment.
---------------------------------------------------------------------------

    \4\ The current federal National Pollution Discharge Elimination 
System (NPDES) program under the CWA does not require permitting 
authorities to issue permits for discharges of wastewater to 
groundwater (See 40 CFR 122.1 and 122.2). The exception is those 
instances in which a discharge to surface water may occur via a 
hydrologic connection between a groundwater and surface water. In 
addition, some states have chosen to exceed federal program 
requirements and do issue such permits. See also U.S. EPA NDPES. 
Permit Writers' Manual, United States Environmental Protection 
Agency, Office of Water, December 1996. EPA-833-B-96-003.
---------------------------------------------------------------------------

    Another reason why these wastewaters should not be categorically 
designated as non-hazardous prior to discharge is because that would 
effectively exclude their treatment sludges as well (by avoiding the 
application of the derived-from rule).\5\ As explained below in more 
detail, treatment sludges from these dilute wastes cannot be assumed to 
be low risk. In fact, treatment sludges can contain high levels of the 
very chemicals (e.g., heavy metals) that caused the original waste to 
be listed. In these cases, the hazard that was identified as the 
original basis of listing has not been removed; it has merely been 
transferred to another type of waste matrix (i.e., from a water to a 
solid).
---------------------------------------------------------------------------

    \5\ These wastes would still be subject to the hazardous waste 
characteristics of 40 CFR Part 261, Subpart C, but, as explained 
later in this preamble section, such coverage would not address all 
the unacceptable risks potentially posed by the chemicals in these 
wastes.
---------------------------------------------------------------------------

    In sum, EPA has excluded (through the wastewater treatment unit 
exclusions) hazardous wastewaters from regulation where we believe 
there is a reasonable basis to do so, grounded in the protection of 
human health and the environment, and the statute excludes from RCRA 
jurisdiction industrial wastewater discharges subject to CWA discharge 
permits. But based on the available data, EPA believes that a blanket 
wastewater exclusion from regulation is not warranted. Instead, EPA 
will continue to develop approaches (e.g., targeted exemptions and HWIR 
exemption levels) to address wastewaters that are be considered low 
risk.

Regulating Derived-From Wastes

    As explained in 40 CFR 261.3(c)(2)(i), any solid waste derived from 
the treatment, storage, or disposal of a hazardous waste is also 
considered a hazardous waste. Specific examples of these derived-from 
wastes include sludges, spill residues, ash, emission control dust, and 
leachate. For derived-from wastes that change location but are 
otherwise unmodified, the question of their continued regulation is 
more straightforward. Because such waste would have the same levels of 
toxic constituents and presumably the same potential exposure patterns 
as the waste that was evaluated for the original hazardous listing 
determination, it would pose the same unacceptable risk as the original 
waste.
    Other types of derived-from wastes may have a different physical 
form than the original waste, but still present the same chemical 
hazard. Leachate derived from the disposal of hazardous waste, for 
example, can contain the same chemicals as found in the original waste. 
When EPA analyzed leachate for purposes of promulgating effluent 
guidelines for landfill leachate (65 FR 3007, January 19, 2000), we 
found that wastewater generated as a result of a particular industrial 
operation can have a similar pollutant profile to leachate generated by 
a landfill receiving the bulk of their waste from that same operation 
(65 FR 3008, 3012, January 19, 2000). During treatment, chemicals in 
hazardous wastewater are transferred to the sludge, which is disposed 
of in the captive landfill. Once the sludge is disposed in a landfill, 
persistent chemicals in this sludge can then transfer to the leachate, 
which, when managed in a wastewater treatment unit, transfers them once 
more to sludge. Although changed in form, the treatment sludge (and 
leachate) could still pose similar unacceptable risks as the originally 
listed waste, depending on actual concentrations and exposure patterns.
    We also found considerable differences between the leachate samples 
from hazardous and those from non-hazardous waste landfills in both 
numbers of constituents of concern and their concentrations. Hazardous 
waste landfill leachate contained a greater number of constituents than 
non-hazardous waste landfill leachate, and constituents found in both 
hazardous and non-hazardous waste landfill leachate were generally 
present in hazardous waste landfill leachate at concentrations an order 
of magnitude higher than those found in non-hazardous waste landfill 
leachate.\6\ Absent a risk assessment, it is not possible to determine 
whether the levels of these constituents pose unacceptable risk. 
However, the presence of such constituents creates a continuing concern 
regarding leachate derived from hazardous waste.
---------------------------------------------------------------------------

    \6\ Development Document for Final Effluent Limitations 
Guidelines and Standards for the Landfills Point Source Category, 
EPA-821-R-99-019, U.S. EPA, January 2000.
---------------------------------------------------------------------------

    The other broad category of derived-from waste are treatment 
residues. At least six commenters cited the D.C. Circuit Court of 
Appeals observation in Shell Oil Co. v. EPA, 590 F.2d at 752 that ``the 
derived-from rule becomes counterintuitive as applied to processes 
designed to render wastes nonhazardous.'' However, the presumption that 
treatment always renders hazardous waste nonhazardous is overly 
simplistic. This presumption does not take into account all products of 
treatment. Even treatment that operates properly is often designed to 
isolate a hazardous residual. For example, wastewater treatment 
designed to produce a sufficiently clean effluent for discharge is also 
designed to move the hazardous constituents from the wastewater into 
the sludge. The resulting de-watered sludge, while much lower in volume 
than the original hazardous wastewater, has the potential to have much 
greater concentrations of hazardous chemicals. As explained above, once 
the sludge is disposed in a landfill, persistent chemicals in this 
sludge can then transfer to the leachate, which, when managed in a 
wastewater treatment unit, transfers them once more to sludge.
    The derived-from rule thus ensures that the chemicals in the 
originally listed waste that are transferred to another matrix when the 
waste is managed remain under RCRA Subtitle C control. Without the 
derived-from rule, a hazardous wastewater could be treated so that 
hazardous constituents are moved to the sludge. If the generator could 
claim that the resulting sludge, regardless of chemical concentration, 
no longer meets the listing description, then that sludge could be 
handled as non-hazardous waste, and placed in an unlined industrial 
landfill, or sent to a land application unit.\7\ The resulting leachate 
would not necessarily be collected. Instead, those chemicals that first 
caused the waste to be listed could potentially now enter the 
environment and, depending on the actual chemical concentrations and 
exposure patterns, could pose unacceptable risks.
---------------------------------------------------------------------------

    \7\ These wastes would still be subject to the hazardous waste 
characteristics of 40 CFR Part 261, Subpart C, but, as explained 
later in this preamble section, such coverage would not address all 
the unacceptable risks potentially posed by the chemicals in these 
wastes.
---------------------------------------------------------------------------

    Other types of treatment, which result in combining wastes with 
different chemical concentrations, can result in dilution of those 
chemicals, but may not adequately address the hazard they could pose. 
As mentioned earlier in the discussion on regulating mixtures, 
combining wastewaters for centralized treatment is often a legitimate 
treatment practice, but the diluting effect of such treatment does not 
address the transfer of persistent chemicals to the sludge.
    Finally, treatment that reduces the amount of organic chemicals in 
a waste does not typically address the risk from

[[Page 27274]]

metals in the waste. For example, biological treatment and 
incineration, which are among the most aggressive forms of treatment, 
are designed to reduce or destroy organic chemicals. However, these 
types of treatment do not address heavy metals and may form chemical 
by-products (e.g., dioxins) that could pose unacceptable risks, if not 
managed properly. For example, baghouses on combustion devices serve to 
collect hazardous constituents that would otherwise be emitted to the 
air from the combustion process, and the dust that is removed from the 
baghouses predictably contains metals that were in the original waste. 
In response to industry comments, EPA will explore specific approaches 
for dealing with biological treatment residues and has already begun 
considering an alternative approach to address combustion residues (See 
Sections X.C. and X.D. of this preamble.) EPA will also continue to 
develop approaches (e.g., targeted exemptions and HWIR exemption 
levels) to exempt other waste streams that are currently captured by 
the derived-from rules but pose low risks.

Historic Information on Mixture and Derived-From Wastes

    As we discussed in the 1999 proposal, EPA's experience with the 
delisting program further supports retaining the mixture and derived-
from rules as a necessary part of hazardous waste identification. 
Generators can petition EPA under 40 CFR 260.22 to exclude a waste 
produced at a particular facility from the definition of hazardous 
waste. Such petitions must demonstrate that the waste does not meet any 
of the criteria for which it was listed nor has other attributes that 
might result in the waste being hazardous.
    Over the 20-year period from 1980 through 1999, EPA reviewed over 
900 petitions to delist wastes, and granted delistings to 136 waste 
streams generated at 115 separate facilities. Most of the petitions 
(i.e., more than 600) were withdrawn or mooted before the review was 
complete; 108 were denied. Most of these denials were based on lack of 
information. In at least 13 of the 36 cases where enough information is 
available in the source documentation to determine whether a waste was 
a mixture or derivative, we denied delisting petitions for mixtures or 
residuals of listed waste because risk analyses indicated that the 
toxicity and leaching potential of hazardous chemicals in those wastes 
posed unacceptable risk to human health. These mixture and derived-from 
wastes had potentially hazardous levels of a wide range of chemicals 
including barium, cadmium, chromium, lead, mercury, nickel, benzene, 
benzo(a)pyrene, cyanide, chloroform, 1,1-dichloroethane, 1,1-
dichloroethylene, 2,4-dinitrotoluene, methylene chloride, 
trichloroethylene, and vinyl chloride.\8\
---------------------------------------------------------------------------

    \8\ U.S. EPA Evaluation of Hazardous Waste Delisting Program, 
December 2000; and Analysis of the Delisting Petition Data 
Management System, U.S. EPA, September 1998). EPA Docket 99-WH2P-
FFFFF.
---------------------------------------------------------------------------

    We have also identified possible damage cases associated with 
mixture and derived-from wastes. For example, there are Superfund sites 
that contain mixture and derived-from wastes (See 50 FR 658). We have 
identified at least twenty sites that may have involved the 
mismanagement of mixture and derived-from wastes.\9\ The sites 
identified include cases of extensive contamination of soils and 
groundwater with metals (e.g., arsenic, lead, mercury), cyanide, and 
organics (e.g., benzene, toluene, and xylenes). It is very difficult to 
identify the full range of damage cases that specifically involve waste 
mixtures or derivatives since neither EPA nor other parties track or 
categorize waste based on its status under the mixture or derived from 
rules.
---------------------------------------------------------------------------

    \9\ EPA 2000. Releases of Hazardous Constituents Associated with 
Mixture and Derived-from Wastes (An Update) U.S. EPA, April 2000.
---------------------------------------------------------------------------

    The legislative history of RCRA also provides examples of damage 
cases caused from disposal of mixture and derived-from hazardous 
wastes. In introducing the purpose of Subtitle C, the House Committee 
on Interstate and Foreign Commerce cited seven pages of damage cases, 
stating, ``The most effective way of illustrating the dangers of 
improper hazardous waste disposal is perhaps to cite actual instances 
of damage caused by current hazardous waste disposal practices. The 
following section is merely illustrative of the problem. Far more cases 
could be cited, even more have gone unreported.'' H.R. Rep. No. 94-1491 
(94th Cong. 2d Sess. 1976) 17-23. Of the 59 instances described in the 
House Committee Report, at least 40 involved spills, leachate or runoff 
from landfills, lagoons or waste storage facilities. Leachate and run-
off are derived-from wastes, as are spills from storage and disposal 
facilities, and some of the sources contained mixtures of hazardous and 
non-hazardous solid wastes.

Intrinsic Chemical Properties of RCRA Hazardous Waste ``Mixtures'' and 
``Derived-From'' Wastes

    We also analyzed the information in EPA's National Hazardous Waste 
Constituent Survey (NHWCS) Database to assess the intrinsic physical 
and chemical properties of RCRA hazardous waste ``mixtures'' and 
``derived-from'' wastes. The purpose of the NHWC Survey was to collect 
descriptive information about the identity and measured concentrations 
of chemical constituents contained in RCRA hazardous wastes. The NHWCS 
was a one-time, voluntary participation mail survey we administered in 
1996, providing a single-year ``snapshot'' of the intrinsic physical 
and chemical properties of RCRA hazardous wastes. It is EPA's most 
comprehensive and current database about hazardous waste constituents. 
We benchmarked the 1996 survey to data already collected in our 1993 
Biennial Reporting System (BRS) database--which contains data provided 
by the 1993 universe of RCRA hazardous waste large quantity 
generators--by pre-loading survey questionnaires with the known 1993 
BRS data for the NHWC survey facilities, and asking facilities to 
verify the known BRS data, as well as to provide new data about the 
known chemical constituents in the RCRA hazardous wastes they managed 
(constituent data are not contained in the BRS database). This analysis 
is presented as a technical supplement to this rulemaking for purpose 
of public understanding of the intrinsic nature of these two groups of 
wastes, which we currently regulate as RCRA hazardous. This 
supplemental analysis corroborates the substance of our proposed rule 
(64 FR 63382-63461, Nov. 19, 1999).
    Although the survey results apply to a subset of the total universe 
of waste and should not be extrapolated to the larger universe of RCRA 
hazardous waste generators, the information provides valuable insight 
into the types and levels of chemicals that could be present in such 
wastes. A large number of waste streams captured in the NHWCS were 
identified by their generators as mixtures of solid waste and hazardous 
waste or derived-from hazardous wastes. The analysis revealed that 
potentially hazardous chemical constituents, have been and can be 
present in wastes mixed with or derived-from, RCRA hazardous wastes. 
Although this analysis is not a quantitative risk assessment, this 
conclusion is supported by the presence of persistent, bioaccumulative, 
and toxic (PBT) chemicals in these two waste groups, some of which are 
at relatively high concentrations. Consequently, we continue to be 
concerned about the potential risks posed by the mismanagement of RCRA 
hazardous

[[Page 27275]]

waste ``mixtures'' and ``derived-from'' wastes.
    For more information about this analysis, please see the background 
document Analysis of RCRA ``Mixtures and Derived-from'' Hazardous Waste 
Constituent Data, which is available to the public from the RCRA 
Docket. The NHWCS database is available to the public via the Internet 
at http://www.epa.gov/epaoswer/hazwaste/id/hwirwste/economic.htm.

Regulatory Coverage by the Toxicity Characteristic

    EPA also does not agree with comments that the mixture and derived-
from rules are not necessary because the Toxicity Characteristic (TC) 
provides regulatory coverage of these wastes. The TC currently sets 
regulatory levels for only 40 chemicals. (see 40 CFR 261.24). On the 
other hand, the hazardous waste listings are based on hundreds of 
different chemicals. (see Appendix VII to 40 CFR Part 261). In 
addition, the TC levels are the result of laboratory analyses to 
predict whether a waste is likely to leach chemicals into groundwater 
at hazardous levels, not the result of a comprehensive risk assessment. 
Depending on the actual constituents in a waste and their 
concentrations, wastes with constituents that fall below TC levels can 
still pose unacceptable risks to human health and the environment if 
mismanaged. (55 FR 11799). EPA has listed wastes based on the presence 
of constituents below the TC levels. For example, in the final listing 
decision for spent hydrotreating and hydrorefining catalysts from 
refinery operations, we analyzed the potential risk from arsenic and 
benzene using input leachate concentrations capped at TC regulatory 
levels. The results of this analysis suggested unacceptable risks posed 
by these wastestreams from concentrations below the TC regulatory 
levels (63 FR 42154). The mixture and derived-from rules are necessary 
for capturing such wastes that could pose unacceptable risks from 
chemicals without TC levels and for risks not addressed by the TC 
approach.

Conclusion

    When EPA determines that a waste is capable of posing a hazard to 
human health or the environment when improperly managed, that 
determination is based on consideration of several different factors, 
including the toxicity, persistence, degradability in nature, the 
potential of chemicals to bioaccumulate in tissue, flammability, 
corrosiveness, and other hazardous characteristics and related factors. 
The act of mixing, storing, disposing or even treating the waste does 
not guarantee removal of the hazard posed by these chemicals, nor does 
it remove EPA's obligation to ensure that the hazards presented by the 
waste continue to be controlled from the cradle to the grave, even when 
it is transferred to another waste matrix. Nevertheless, EPA will 
continue to develop approaches to exempt low-risk wastes from full 
Subtitle C regulation, as appropriate. Since the original promulgation 
of the mixture and derived-from rules, we have invited suggestions as 
to better ways of handling the difficult issues associated with the 
mixing, treating, storing, disposing, and otherwise managing waste 
following its generation. See 45 FR 33095 (May, 19, 1980). We have 
considered and are continuing to pursue suggestions for targeted 
exemptions (e.g., the CMA suggestions discussed at Section X of the 
preamble) as well as a risk-based exit level approach to identifying 
low-risk wastes.

B. Legality of the Mixture and Derived-From Rules

    EPA received comments in response to both the 1995 and 1999 HWIR 
proposals on RCRA Subtitle C jurisdiction over mixtures and derivatives 
from the management of listed hazardous wastes. Of the 42 commenters 
who specifically commented on the statutory authority for these rules, 
38 were received from industry (including utilities and trade 
associations), two were from waste management companies, one was from a 
waste management association and one was from an individual commenter. 
Almost all these comments expressed the view that EPA lacked statutory 
authority to promulgate these rules, although other commenters who 
generally supported retention of the mixture and derived-from rules 
expressed the view that these wastes are properly under RCRA Subtitle C 
jurisdiction.
    The waste management association agreed that EPA had statutory 
authority under RCRA to promulgate the mixture and derived-from rules 
in 1980, and that EPA also had ample authority to retain the basic 
rules now without change. The commenter, citing Shell Oil Corp. v. EPA, 
believed that the rules were consistent with EPA's legal authority 
under RCRA section 3001 to determine when wastes are hazardous based on 
listing criteria, and under RCRA sections 3002-3004 to impose 
regulatory standards until wastes have ceased to pose a hazard to the 
public.
    As noted, most commenters expressed the view that EPA is acting 
beyond its statutory authority by retaining the mixture and derived-
from rules. These comments asserted three main points: (1) Mixture and 
derived-from wastes do not meet the statutory definition of hazardous 
under RCRA section 1004(5); (2) EPA has not met the requirements under 
section 3001, 42 U.S.C. Section 6921 and 40 CFR 261.10 and 261.11 for 
designating wastes as hazardous; and (3) EPA has no authority under 
sections 3002-3004 of RCRA to designate wastes as hazardous. A summary 
of each of these specific issues raised by commenters, and EPA's 
response to these issues, is provided below. For more information on 
these comments and EPA' responses, please see Hazardous Waste 
Identification Rule: Revisions to the Mixture and

Derived-From Rules Response to Comments Document.

(1)(a) Comment: Mixture and Derived-From Wastes Do Not Meet the 
Statutory Definition of Hazardous Under RCRA Section 1004(5)
    Numerous commenters from industries, industry associations, utility 
companies, utility company associations and waste management companies 
generally believed that the mixture and derived-from rules were too 
broad and swept in many wastes which did not meet the statutory 
definition of hazardous wastes, and that the derived-from rule in 
particular was not supported by statutory authority. One commenter even 
felt that the derived-from rule was a ``legal fiction'' because 
treatment residuals must be managed as if the treatment had not 
occurred. Commenters noted that EPA only was authorized under the 
Resource Conservation and Recovery Act (RCRA) to designate as hazardous 
waste those solid wastes that EPA determined may (1) cause, or 
significantly contribute to an increase in mortality or serious 
illness, or (2) pose a substantial present or potential hazard to human 
health or the environment when improperly managed (RCRA section 
1004(5), 42 U.S.C. 6903(5)). Commenters expressed the view that EPA can 
regulate under Subtitle C only those solid wastes that EPA determined 
pose substantial hazards per the language in Section 1004(5) of RCRA. 
Many commenters also noted that, in their view, many of these wastes 
pose minimal or no threat to the environment and public health. The 
majority of these commenters believed that EPA made no attempt to 
demonstrate that derived-from wastes met the statutory definition of 
hazardous waste. Instead, these commenters believed EPA simply drew 
conclusions that these materials were

[[Page 27276]]

hazardous waste, even though many derived-from wastes had not met the 
statutory definition of hazardous waste. They also noted that EPA has 
admitted that many derived-from wastes pose little risk to human health 
or the environment. Therefore, they claim that the derived-from rule 
was not a legally valid approach to regulating materials that result 
from the management of hazardous waste.
(1)(b) EPA Response
    While we agree that the mixture and derived-from rules capture some 
waste that may actually pose quite low hazard, we have implemented and 
continue to pursue approaches (such as today's revisions) to exclude 
such waste from full Subtitle C regulation. Nevertheless, these rules 
are a necessary component of cradle-to-grave waste management, to 
protect human health and the environment from unacceptable risks. EPA 
does not agree with comments that mixtures and derivatives do not meet 
the definition of ``hazardous waste'' in section 1004(5) of RCRA, nor 
do we agree that Congress did not intend these wastes to be regulated 
under Subtitle C of RCRA.
    The definition of hazardous waste is a broad definition which 
encompasses solid wastes or combinations of solid wastes which, because 
of their ``quantity, concentration, or physical, chemical, or 
infectious characteristics may * * * pose a substantial present or 
potential hazard to human health or the environment when improperly 
treated, stored, transported or disposed of, or otherwise managed.'' 
Because they originate from waste that has already been determined to 
be hazardous, EPA has a reasonable basis to conclude that mixtures and 
derivatives could also pose a potential or present hazard to human 
health or the environment if not properly managed. The original listing 
of the waste already establishes the reasons, i.e., the ``quantity, 
concentration, or physical, chemical, or infectious characteristics'' 
for having identified the listed waste as hazardous. It is reasonable 
to conclude, without information to the contrary, that both mixtures 
and derivatives of such wastes may pose a substantial potential or 
present hazard to human health or the environment if not properly 
managed, and therefore fall under the definition of hazardous waste in 
RCRA section 1004(5).
    Nothing in the section 1004(5) definition of hazardous waste 
requires EPA to prove that every member of a category of waste poses a 
hazard. In fact, many waste listings describe categories or ``classes'' 
of hazardous wastes because they cover a range of materials that are 
not identical in composition.
    EPA also does not agree with commenters' assertion that wastes 
derived from the treatment, storage, or disposal of listed hazardous 
wastes in particular do not meet the section 1004(5) definition. As 
explained in section VII.A.2, residuals from the treatment of hazardous 
wastes can contain higher concentrations of the chemicals that led to 
the hazardous waste listing in the first place, and therefore may pose 
a present or potential hazard to human health or the environment if 
improperly managed. Indeed, the objective of many forms of treatment is 
precisely to isolate and collect hazardous constituents, often in 
concentrated form, for further management. For example, de-watering of 
waste, e.g., to make it easier to transport, is a form of treatment 
that often does not significantly change the character of the waste 
other than to leave it in a more compact and concentrated form. At the 
more aggressive end of the treatment spectrum, baghouses on hazardous 
waste combustion devices collect hazardous constituents that would 
otherwise be emitted to the air from the combustion process, creating 
dust that predictably contains any metals that were in the original 
wastes as well as products of incomplete combustion. Congress 
specifically expressed concern in RCRA about treatment residues created 
by federal and state pollution control laws, RCRA 1002(b)(3). The 
potential for persistent hazardous constituents in treatment residues 
and the Congressional findings in the RCRA statute support EPA's 
conclusion that residuals from the treatment, storage and disposal of 
listed hazardous waste may pose a substantial present or potential 
hazard.
    EPA acknowledges that not all mixtures and derivatives pose hazards 
to human health and the environment (see, e.g. 57 FR 21451). There are 
mechanisms to address this fact, and we are continuing to pursue 
approaches to exempt low-risk wastes. First, RCRA and EPA regulations 
provide for the delisting of listed hazardous waste. RCRA 3001(f); 40 
CFR 261.20 and 40 CFR 261.22. Since the federal delisting program took 
effect in 1980, EPA has excluded an estimated 45 million tons of waste, 
resulting in an estimated cumulative cost savings between $1.1 billion 
and $1.3 billion dollars (in 1999 dollars). In 2000 alone, we estimate 
cost savings of approximately $105.4 million.\10\ In the 1995 HWIR 
proposal, EPA stressed the continued need for the delisting program, 
although we also acknowledged that it had not provided an efficient 
solution to the regulation of low-risk wastes. However, as discussed in 
Section VIII.C of this preamble, since the delisting program was 
delegated to the EPA Regions on October 10, 1995, a number of 
innovations have been adopted that have greatly improved the efficiency 
and effectiveness of the delisting program. EPA will continue these 
efforts and others in order to keep improving the delisting process.
---------------------------------------------------------------------------

    \10\ U.S. EPA Evaluation of Hazardous Waste Delisting Program, 
December 2000.
---------------------------------------------------------------------------

    In addition, as EPA has identified specific mixtures and derived-
from wastes which no longer meet the definition of hazardous waste, and 
has therefore established a number of exclusions in 40 CFR 261.3. 
Currently, there are over a dozen types of hazardous waste mixtures and 
residuals excluded or conditionally exempted under section 261.3. See 
the ``Table of Revisions to 40 CFR 261.3'' in Section VII.C.2 of this 
notice for a list of these exclusions. This is in addition to other 
exclusions and conditional exclusions set forth in 40 CFR 261.4 as well 
in other parts of the hazardous waste regulations.
    Furthermore, as discussed in Section VI of this notice, EPA is 
continuing work to develop exit levels for listed hazardous wastes, so 
that listed wastes can become ``delisted'' automatically, under a self-
implementing procedure. But, as also explained in Section VI of this 
notice, that is a complex undertaking and, despite best efforts, EPA is 
not able at this time to propose a technically supported concentration-
based exemption.\11\ Also, as explained in Section X of this preamble, 
we are also investigating and will actively pursue other specific 
exemption proposals.
---------------------------------------------------------------------------

    \11\ Congressional report language accompanying EPA's FY 2001 
appropriations act directs EPA to submit the HWIR model to an 
independent peer review, and respond publicly to the findings of the 
peer review prior to using it to establish regulatory 
determinations. S. Rep. No. 106-410 at 90 (2000) ). EPA is currently 
in the process of preparing for that peer review.
---------------------------------------------------------------------------

    EPA continues to believe, as it did in 1980, that it would be 
virtually impossible to try to identify all possible waste mixtures and 
treated wastes and assess their hazards individually. EPA's rule 
reasonably retains jurisdiction over both broad classes and places the 
burden of proof on the regulated community to show that a particular 
waste has ceased to present a hazard.
    Even if all listed hazardous waste mixtures and derivatives could 
not be

[[Page 27277]]

said to meet the statutory hazardous waste definition, at the very 
least it is reasonable and consistent with RCRA to presume that 
mixtures and derivatives of listed hazardous wastes remain hazardous 
under the definition, unless that presumption is rebutted through the 
delisting process. As discussed further in the next section, Congress 
established clear standards for hazardous waste identification, but did 
not speak specifically to the issue of the circumstances under which 
mixtures and derivatives of listed hazardous wastes should be 
regulated. Under these circumstances, EPA must interpret and implement 
the statute in a way that effectuates the statutory objectives. The 
mixture and derived-from rules are the only implementation approach 
that EPA is aware of at this time that effectuates the protective 
purposes of RCRA.
(2)(a) Comment: EPA Has Not Met the Requirements Under Section 3001, 42 
U.S.C. 6921 and 40 CFR 261.10 and 261.11 for Designating Wastes as 
Hazardous
    These commenters also disagreed with EPA's claim of authority under 
section 3001 (60 FR at 66348, 64 FR 63390). The commenters believed 
that EPA had not followed the required procedures or made the findings 
required by RCRA to identify ``mixture and derived-from wastes'' as 
hazardous. They noted that sections 3001(a) and (b) outline a two-step 
process for classifying wastes as hazardous. EPA first must specify 
criteria to determine if the waste is ``hazardous,'' 42 U.S.C. 6921(a), 
which is defined as presenting a substantial present or potential 
hazard to human health or the environment 42 U.S.C. 6904(5). Once the 
criteria are established--as they have been in 40 CFR 261.10 and 
261.11--the commenters stated that EPA must apply these criteria to 
identify a characteristic of hazardous waste or to list a waste as 
hazardous. In these commenters' view, the mixture and derived-from 
rules identify a broad class of wastes as hazardous without regard to 
the criteria established by EPA. Also, they noted that the proposal did 
not discuss how mixtures and derived-from wastes pose a substantial 
present or potential threat to human health or the environment, nor did 
EPA discuss concentration levels, mobility, persistence, or any other 
objective factors of hazardousness that are listed in the statute or 
the regulations.
    In addition, numerous commenters from industries, industry 
associations, utility companies and utility company associations 
disagreed with EPA identifying mixture and derived-from wastes as a 
``class'' under 40 CFR 261.11 (60 FR at 66348, 64 FR at 66390). They 
believed that such identification required a finding that EPA had 
reason to believe that individual wastes within the class ``typically 
or frequently are hazardous'' under the definition at RCRA section 
1004(5) (see 40 CFR 261.11(b)). Commenters noted that EPA's own 
longstanding practice was that, in a class-wide listing determination, 
``typically or frequently'' meant that more than 50 percent of the 
samples taken from that class exhibited some or all of the 40 CFR 
261.11(a) criteria (see, e.g., 56 FR 48020, Sept. 23, 1991 and 45 FR 
33114, May 19, 1980). The commenters stated that EPA historically has 
required that samples of a waste class contain concentrations of toxic 
constituents at 100-1000 times specified health-based numbers to be 
considered as posing a ``substantial hazard'' under 40 CFR 261.11(a)(3) 
(see, e.g., 56 FR. 48018, Sept. 23, 1991 and 57 FR 21453, May 20, 
1992). They noted that EPA generally requires that wastes typically and 
frequently contain toxic constituents at ``many times'' health-based 
levels and that such constituents be mobile and persistent. The current 
proposal made no reference to these prior practices, nor did it offer 
evidence that EPA collected or analyzed any samples or otherwise 
attempted to demonstrate that 50 percent--or any substantial 
percentage--of mixtures or treatment residues met any of the specific 
criteria of Sec. 261.11(a). Also, they commented that the proposal 
offered nothing responsive to the 100-1000 times health-based numbers 
requirement. In addition, they noted that the class must have 
``sufficient uniformity'' to apply the criteria in 40 CFR 261.11 (45 FR 
33114). The commenters felt that it was obvious that the class of 
mixture and derived-from wastes was anything but uniform, a point 
admitted by EPA (45 FR 33095-96, ``the potential combinations of listed 
wastes and other wastes are infinite''). Therefore, the class did not 
have the requisite uniformity needed to be classified as hazardous.
(2)(b) EPA Response
    EPA does not agree with comments that the Agency lacks statutory 
authority under RCRA Section 3001 for either the mixture rule or the 
derived-from rule. We have the statutory authority to promulgate these 
rules as part of the authority to ``develop and promulgate criteria for 
identifying the characteristics of hazardous waste and for listing 
hazardous waste.'' Among the criteria are the provisions of 40 CFR 
261.3, which provide generally applicable criteria for the 
identification of hazardous waste. The mixture and derived-from rules 
are included in section 261.3(a)(2), which states that a solid waste is 
a hazardous waste if ``[i]t meets any of the following criteria.'' 
These rules ensure that listed hazardous wastes that are mixed with 
other wastes or treated in some fashion do not escape regulation as 
hazardous waste until EPA has made some determination that they no 
longer threaten human health or the environment. This section also 
includes the exclusions from the definition of hazardous waste, 
including those promulgated today, where EPA has made specific findings 
on the record that the excluded wastes are no longer hazardous under 
the criteria set forth in the exclusions. We will continue to pursue 
additional approaches to exempt low-risk wastes, as appropriate.
    The commenters' position rests largely on the assumption that 
mixtures and derivatives of wastes are entirely new and distinct 
substances from the originally listed waste, leading to the apparent 
conclusion that EPA must make a separate, record-based finding of 
hazardousness for each of the infinite variations of mixtures and 
derivatives generated from the wastes EPA has listed. EPA disagrees. In 
upholding the ``contained-in policy,'' the U.S. Court of Appeals for 
the D.C. Circuit deferred to EPA's conclusion that a listed hazardous 
waste cannot be presumed to change character when it is mixed with an 
environmental medium. Chemical Waste Management v. EPA, 869 F.2d 1526, 
1539 (1989). We believe that the same reasoning applies to the mixture 
rule. Similarly, as discussed in Section VII.A.2, waste management 
residuals can contain constituents from the originally listed waste at 
even higher concentrations than the original waste and, therefore, may 
pose a hazard. Indeed, EPA views the mixture and derived-from rules as 
applications of the general principle that ``a hazardous waste will 
remain a hazardous waste'' unless it is excluded through a regulatory 
process. 40 CFR 261.3(c)(1). See Chemical Waste Management, 869 F.2d at 
1539 (upholding contained-in policy as interpretation of 
Sec. 261.3(c)(1)).
    EPA's approach is consistent with Congress' intention that 
hazardous waste be regulated for the long term under a comprehensive 
regulatory program. One of the findings upon which the 1976 RCRA 
legislation was based was that ``hazardous waste presents, in addition 
to the problems associated with nonhazardous solid waste, special 
dangers to health and requires a greater degree of regulation than does 
nonhazardous solid waste.''

[[Page 27278]]

Public Law No. 94-580, section 1002(5). With enactment of the Hazardous 
and Solid Waste Amendments (HSWA) in 1984, Public Law No. 98-616, 
Congress strengthened that provision and added three more findings: 
``the placement of inadequate controls on hazardous waste management 
will result in substantial risks to human health and the environment; 
if hazardous waste management is improperly performed in the first 
instance, corrective action is likely to be expensive, complex , and 
time consuming; certain classes of land disposal facilities are not 
capable of assuring long-term containment of certain hazardous wastes * 
* *''. RCRA section 1002(b)(5), (6), (7). Similarly, when RCRA was 
enacted in 1976, Congress stated one of the objectives of the Act was 
``regulating the treatment, storage, transportation, and disposal of 
hazardous wastes which have adverse effects on health and the 
environment.'' Public Law No. 94-580, 1003(a)(4). This provision too 
was replaced with a stronger statement by HSWA, that an object of the 
statute is ``assuring that hazardous waste management practices are 
conducted in a manner which protects human health and the 
environment.'' (Emphasis added.) RCRA 1003(a)(4). Further, HSWA added 
as national policy that hazardous waste ``should be treated, stored, or 
disposed of so as to minimize the present and future threat to human 
health and the environment.'' RCRA 1003(b). It is clear that Congress' 
principal objective under Subtitle C was protecting against threats to 
human health and the environment caused by hazardous waste. We 
acknowledge that such a goal does not imply that all mixtures and 
derived-from wastes must be regulated under full Subtitle C 
requirements, regardless of the potential risks they pose, but we 
believe that it is reasonable to regulate these wastes until it is 
shown that such wastes do not pose a hazard.
    The D.C. Circuit Court of Appeals has characterized RCRA as 
establishing ``a ``cradle-to-grave'' regulatory structure overseeing 
the safe treatment, storage and disposal of hazardous waste.'' United 
Technologies Corp. v. EPA, 821 F.2d 714, 716 (D.C. Cir. 1987). The 
mixture and derived-from rules are a necessary part of this approach, 
by maintaining jurisdiction over mixtures and derivatives of already 
listed waste. Without these rules, as explained in Section VII.A.(2), 
the ``cradle-to-grave'' structure would have a major loophole, 
undermining the objectives of RCRA.
    The delisting provision supports the mixture and derived-from rules 
as a means to address wastes that could pose unacceptable risks. In 
amending RCRA section 3001 in 1984, Congress enacted subsection (f) to 
require the Agency to ``consider factors (including additional 
constituents) other than those for which the waste was listed'' if the 
Agency ``has a reasonable basis to believe that such additional factors 
could cause the waste to be a hazardous waste.'' The legislative 
history shows that Congress was concerned that both as generated wastes 
and wastes resulting from treatment were exiting the Subtitle C system 
while still hazardous. ``The delisting process allows petitioners 
(usually individual hazardous waste generators or treatment facilities) 
the opportunity of showing that their wastes are significantly 
different--because of treatment, or because they are generated in a 
different process--from listed wastes of the same type. * * * Under 
this amendment, there would no longer be a risk that delisting a waste 
means releasing waste which may still be hazardous from regulation.'' 
H.R. Rep. No. 98-198 Part I (May 17, 1983). Congress made this change 
because it believed that under its previously existing delisting 
regulations, EPA allowed wastes that remained hazardous to exit the 
Subtitle C system. S. Rep. No. 98-284 (Oct. 28, 1983). The language and 
legislative history reflect Congress' assumption that treatment 
derivatives from listed wastes would remain subject to Subtitle C 
absent a delisting.
    The land disposal restrictions (LDR) provisions of the statute 
further demonstrate that the mixture and derived-from rules are 
consistent with Congress' intent. The statute authorizes EPA to 
promulgate regulations establishing levels or methods of treatment, 
``if any,'' that substantially diminish the toxicity or mobility of the 
hazardous waste, and provide that the waste may thereafter be disposed 
of in a land disposal facility that ``meets the requirements of 
[Subtitle C].'' RCRA section 3004(m). This section demonstrates two 
things. (1) Congress contemplated the possibility that there may be 
hazardous wastes for which no form of treatment would be adequate; and 
(2) Congress assumed that waste that was treated according to the 
promulgated treatment standards would nonetheless still be disposed of 
in a Subtitle C (hazardous waste) facility. This provision is at odds 
with the commenters' assertion that, once treated, a hazardous waste 
becomes a fundamentally different waste and is unregulated unless EPA 
undertakes a separate rulemaking to list the treated waste.
    Other provisions of the 1984 amendments to RCRA relating to land 
disposal provide further support for the mixture and derived-from 
rules. See, e.g., section 3004(o) (establishing minimum technological 
requirements for land-based hazardous waste management units); section 
3004(p) (establishing groundwater monitoring requirements); section 
3005(c)(3) (requiring 5-year permit reviews for land disposal 
facilities); section 3005(e)(2), (3) (establishing interim status 
termination dates for certain non-compliant land disposal facilities); 
section 3005(i), (j) (establishing specific additional requirements for 
certain land-based units); section 1002(b)(7) (finding that certain 
classes of land disposal facilities are not capable of assuring long-
term containment). Some commenters suggest that treatment residuals 
from listed hazardous wastes do not remain hazardous. We believe it is 
unlikely Congress would have created such stringent requirements for 
land disposal, if it intended for treatment residuals to escape 
Subtitle C regulation.
    Taken to the extreme, the view that mixtures containing listed 
wastes should not be regulated as hazardous wastes would imply that 
most listed hazardous wastes, even if they reached a management unit in 
``pure'' form, would cease to be hazardous once they entered the unit, 
since most units contain mixtures of different wastes. However, the 
RCRA statute clearly assumes that units would not only receive, but 
continue to contain, hazardous waste. See, e.g. section 3005(j)(11) and 
(12)(A), Moreover, the comprehensive requirements mandated for 
hazardous waste management units, including the technical standards of 
section 3004 and the permitting regime of section 3005, could be 
undermined if facilities receiving listed hazardous wastes could argue 
that their management units are subject to this scheme only as long as 
they are receiving the waste, but that they become exempt thereafter 
since the units do not contain hazardous waste.
    Various provisions in RCRA appear to contemplate that at least some 
hazardous waste mixtures and derivatives would themselves be hazardous. 
See, e.g., section 3004(d)(2)(A), (B) (addressing liquid hazardous 
wastes, ``including free liquids associated with any solid or sludge,'' 
suggesting that liquid derivatives of hazardous waste would themselves 
be hazardous). Another example is the language in section 3005(b), 
which requires permit applicants to provide information regarding 
hazardous wastes and ``combinations of * * * hazardous waste and any 
other solid waste'' to be

[[Page 27279]]

managed at the permitted facility, as well as information regarding the 
site at which the ``products of treatment'' of hazardous waste will be 
managed.
    Finally, the appropriations act provision that EPA is implementing 
with today's rule requires that the mixture and derived-from rules 
would continue in effect while EPA developed revisions to the 
regulations. Public Law No. 102-389, 106 Stat. 1571 (October 1992). 
That provision instructed EPA to ``promulgate revisions to paragraphs 
(a)(2)(iv) and (c)(2)(i) of 40 CFR 261.3, as reissued on March 3, 1992 
* * *''. Congress expressed no intent that these rules be rescinded or 
replaced.
    We also disagree with commenters' assertion that the mixture and 
derived-from rules violate the ``two-step process'' of section 3001(a) 
and (b) for hazardous waste identification. It is true that the statute 
requires EPA to promulgate criteria for hazardous waste identification 
(section 3001(a)) and, based on those criteria, to identify 
characteristics of hazardous waste and to list hazardous wastes 
(section 3001(b)). In general, EPA has done this in separate steps. See 
40 CFR part 261, Subpart B (criteria) and Subparts C and D 
(characteristics and lists). However, the statute does not preclude EPA 
from creating self-implementing criteria, as EPA has done with the 
mixture and derived-from rules. EPA does not interpret 3001(b) as 
imposing an obligation on EPA to undertake a separate waste 
identification rulemaking step following the development of self-
implementing criteria. Alternatively, the mixture and derived-from 
rules could be viewed as a simultaneous exercise of EPA's 3001(a) and 
3001(b) authority. Nothing in the statute prevents EPA from 
simultaneously, in combined regulations, establishing the criteria for 
waste identification, and identifying the characteristics of hazardous 
waste and listing waste.
    We agree with commenters who point out that EPA has not used the 
class listing process under 40 CFR 261.11(b) to list mixtures and 
derived-from wastes as a class. However EPA does not agree that 
mixtures and derivatives must be individually listed or identified as 
hazardous wastes before being subject to Subtitle C jurisdiction. As 
previously stated, mixtures and derivatives are identified as hazardous 
waste by virtue of containing or coming from wastes that have been 
listed pursuant to the criteria in 40 CFR 261.11. EPA cannot presume 
that the hazardous constituents that are the basis of the original 
listing are always eliminated or rendered nontoxic simply because a 
waste is mixed with other wastes or managed in some fashion.
(3)(a) Comment: EPA Has No Authority Under Sections 3002-3004 of RCRA 
To Designate Wastes as Hazardous
    Several commenters from industries, industry associations, utility 
companies, utility company associations and waste management companies 
also disagreed with EPA's claim of authority under sections 3002-3004 
of RCRA. They argued that these sections of RCRA provide for hazardous 
waste management standards for generators, transporters, and treatment, 
storage and disposal facilities, not for identifying hazardous wastes. 
Instead, that role is unambiguously carried out by section 3001. 42 
U.S.C. 6921, and in previous promulgations and in litigation, EPA 
relied primarily on section 3001 to justify the mixture and derived-
from rules.
(3)(b) EPA Response
    In citing sections 3002-3004 in the discussion of EPA's statutory 
authority, we did not intend to imply that these sections by themselves 
provide statutory authority for the mixture and derived-from rules. 
Rather, our intent was to explain that these sections inform the 
process of identifying hazardous waste under section 3001 because the 
purpose of identifying a solid waste as hazardous is to ensure that it 
is managed properly.
    The statute directs EPA to regulate hazardous waste generators 
(section 3002(a)), hazardous waste transporters (section 3003(a)), and 
hazardous waste treatment, storage, and disposal facilities (section 
3004(a)) ``as necessary to protect human health and the environment.'' 
It is our view that this informs the decision of when waste should be 
identified as hazardous and therefore subject to the regulatory 
requirements of Subtitle C . In deciding whether to identify a waste as 
hazardous under section 3001, EPA considers whether Subtitle C controls 
on the waste are necessary to protect human health and the environment. 
We have therefore consistently interpreted section 3001 to give us 
broad flexibility in fashioning criteria for hazardous wastes to enter 
or exit the Subtitle C regulatory system. See, Military Toxics Project 
v. EPA, 146 F.3d 948, 958 (D.C. Cir. 1998). As discussed above, this 
interpretation is consistent with the statutory purpose of protecting 
human health and environment by establishing a comprehensive hazardous 
waste regulatory program. (RCRA sections 1002, 1003).
    In addition to providing the context in which the determination of 
whether a waste ``should be subject to the requirements of Subtitle 
C,'' sections 3002-3004 allow us to continue to impose requirements on 
waste handlers until wastes have ``cease[d] to pose a hazard to the 
public.'' Shell Oil Co. v. EPA, 959 F.2d 741, 754 (D.C. Cir. 1991). See 
also Chemical Manufacturers Assoc. v. EPA, 919 F.2d 158, 162-65 (D.C. 
Cir. 1990) (EPA may regulate the disposal of nonhazardous wastes in a 
hazardous waste impoundment under section 3004) and Chemical Waste 
Management, Inc. v. EPA, 976 F.2d 2, 8, 13-14 (D.C. Cir. 1992) (EPA may 
require further treatment of wastes under section 3004 even though they 
cease to exhibit a hazardous characteristic). Without the mixture and 
derived-from rules, EPA could not effectively carry out its obligation 
under sections 3002-3004 to protect human health and the environment. 
Thus, in addition to the specific authority of section 3001, the 
mixture and derived-from rules are authorized under section 2002(a)(1), 
which empowers the Administrator to ``prescribe * * * such regulations 
as are necessary to carry out his functions'' under RCRA.

C. Regulatory Cost of the Mixture and Derived-From Rules

(1) Summary of Comments on the Regulatory Cost of the Mixture and 
Derived-From Rules
    EPA received comments from five commenters in response to both the 
1995 and the 1999 HWIR proposals concerning the regulatory cost of the 
mixture and derived-from rules. Of those comments, four were received 
from industries, and one was from an industry association. The 
commenters generally argued that the rules constituted over-regulation 
of low-risk wastes causing high costs and heavy burdens with little 
benefit to human health and the environment. A summary of the specific 
issues raised by commenters is provided below.
    One industry commenter argued that the rules have added significant 
costs to the operation of manufacturing facilities throughout the 
nation, while providing insignificant benefits to human health and the 
environment. The commenter noted that the generation of large 
quantities of hazardous wastewaters based solely on the practice of 
efficient, centralized wastewater treatment has led the company to 
evaluate the segregation of hazardous and non-hazardous wastewaters, to 
prevent the attachment of a ``hazardous'' label to those non-hazardous 
wastewaters. Such a segregation would require a second treatment 
facility and much re-piping,

[[Page 27280]]

with the net result that millions of dollars would be expended and 
there would be no improvement in the wastewaters ultimately discharged 
to the environment through two, rather than one, discharge points. All 
that would be achieved is an apparent reduction in hazardous waste 
generation which does not, in reality, represent a decrease in waste 
generation, treatment or discharge, but rather a reporting game and 
artificial waste minimization driven by EPA requirements. It is this 
kind of ``game'' that compromises the credibility of both EPA and the 
regulated community and imposes a significant burden on the regulated 
community.
    Another industry commenter noted that managing the residuals as if 
they were listed hazardous waste was significantly more expensive than 
managing the waste in accordance with solid waste regulations. For 
example, in 1995 transportation and disposal of ash from a hazardous 
solids incinerator cost approximately $185,000. In comparison, the ash 
could be managed in a state permitted Subtitle D landfill as non-
hazardous waste for about $25,000. Another industry stated that these 
rules have resulted in significant expense that has diverted resources 
away from greater environmental opportunities.
    One association commenter stated that the rules frequently cause 
waste codes to be carried through and applied to wastes that are 
fundamentally different from the original waste considered in the 
development of the listing classification. The commenter noted that 
there are many instances in which the risk associated with the original 
listed waste simply does not carry through in the same way, and that 
the composition and nature of any risk posed by these materials often 
bears little or no relationship to the original listed waste. Specific 
examples cited include (1) Wastewaters where most of the arsenic has 
been precipitated and removed, (2) debris from hazardous waste 
refractories undergoing repair, and (3) wastewaters that had received 
ethylene oxide as part of an emergency incident. The costs and impacts 
of this automatic waste-code carry-through are quite significant. Much 
of the industry operates through smaller ``batch'' processes, while the 
regulations are crafted for a continuous manufacturing process. And, in 
many operations, delisting the mixture is not an option, as the 
facility can only store the mixture on-site for 90 days, which is not 
enough time for a delisting.
    An industry association also stated that the costs imposed by the 
rules from a number of member companies are easy to identify: on-site 
storage costs, paperwork and administrative costs, higher shipping and 
transportation costs, and higher treatment, storage and disposal costs. 
And, these are the same types of costs analyzed and tallied by EPA in 
documenting the cost savings it attributes to the modified exemption 
for hazardous wastes listed solely for a characteristic of 
ignitability, corrosivity and/or reactivity. The commenter also stated 
that another significant cost of the current regulatory regime was the 
extra time and effort required to evaluate and apply the rules in the 
real world. Even after 20 years, facilities still have difficulty 
evaluating when, whether and why certain waste streams must be managed 
as Subtitle C hazardous wastes under this approach.
2. Response to Comments on Regulatory Cost of the Mixture and Derived-
From Rules
    We agree that the mixture and derived-from rules have captured 
wastes that could safely be managed outside of RCRA Subtitle C 
regulation. As explained below, we have addressed specific cases of 
such over-regulation through targeted rulemaking in the past, and we 
will continue to explore options for exempting wastes that do not 
warrant Subtitle C regulation. However, we do not agree that hazardous 
waste regulation of mixture and derived-from waste provides no 
additional protection of human health and the environment. For example, 
as we discuss in Section VII.A, wastewaters prior to discharge may 
contain constituents at levels that could pose unacceptable risks if 
they are mismanaged. Furthermore, the mixture and derived-from rules 
address cross-media transfer of persistent hazardous chemicals from the 
wastewater to the treatment sludge.
    One way of reducing the regulatory burden available to individual 
waste generators is the delisting process. Generators have the option 
of petitioning the Agency under 40 CFR 260.20 and 40 CFR 260.22 to 
exclude their wastes from the lists of hazardous wastes in subpart D of 
part 261 if they believe those wastes no longer pose risk to human 
health and the environment. Since the delisting program was delegated 
to the EPA Regions on October 10, 1995, a number of innovations have 
been adopted that have greatly improved the efficiency and 
effectiveness of the delisting program. In particular, EPA Region VI's 
award-winning program has created a process that produces a decision 
within an average of 180 days, provides a streamlined application 
checklist, proactively coordinates with State personnel, and includes a 
user-friendly, stand-alone software program that produces an updated, 
state-of-the art assessment of risks associated with delisting a 
petitioned waste. In addition, EPA and the applicant now work together 
to develop an initial application that can be approved without the need 
for major revisions, which is a major factor in reducing the processing 
time. EPA will continue these efforts and others in order to keep 
improving the delisting process. Since 1980, EPA has excluded an 
estimated 45 million tons of waste, resulting in an estimated 
cumulative cost savings between $1.1 billion and $1.3 billion (in 1999 
dollars). In 2000 alone, we estimate cost savings of approximately 
$105.4 million.\12\
---------------------------------------------------------------------------

    \12\ U.S. EPA Evaluation of Hazardous Waste Delisting Program, 
December 2000.
---------------------------------------------------------------------------

    In addition, EPA has taken steps since the mixture and derived-from 
rules were promulgated in 1980 to further reduce the scope, and 
therefore the cost, of these rules when appropriate. As one commenter 
to the 1999 proposal pointed out, eighteen months after the original 
mixture and derived from rules, EPA promulgated the first of several 
exclusions for low-risk waste from the definition of hazardous waste. 
Over the past twenty years, EPA has developed exclusions and/or 
tailored regulations to reduce the regulatory cost for more than a 
dozen types of hazardous waste mixtures and residuals. (see table 
below)

[[Page 27281]]



 Revisions to 40 CFR 261.3 That Have Reduced the Regulatory Cost of the
                     Mixture and Derived-From Rules
------------------------------------------------------------------------
                                  Hazardous waste(s)   Year promulgated
          CFR citation                 affected          (FR citation)
------------------------------------------------------------------------
40 CFR 261.3(a)(2)(iv)(A) and     Certain solvents    1981 (46 FR 56582)
 (B).                              managed in
                                   wastewater
                                   treatment systems.
40 CFR 261.3(a)(2)(iv)(C).......  Certain petroleum   1981 (46 FR 56582)
                                   wastes discharged   Additional wastes
                                   to the refinery     added in 1998 (63
                                   oil recovery        FR 42184)
                                   sewer.
40 CFR 261.3(a)(2)(iv)(D).......  De minimis losses   1981 (46 FR 56582)
                                   of commercial
                                   chemical product.
40 CFR 261.3(a)(2)(iv)(E).......  Certain laboratory  1981 (46 FR 56582)
                                   wastewaters.
40 CFR 261.3(a)(2)(iv)(F) and     Certain carbamate   1995 (60 FR 7848)
 (G).                              wastewaters.
40 CFR 261.3(a)(2)(v)...........  Used oil..........  1992 (57 FR 41611)
40 CFR 261.3(c)(2)(ii)(A).......  Certain waste       1984 (49 FR 23284)
                                   pickle liquor
                                   sludges.
40 CFR 261.39(c)(2)(ii)(B)......  Wastes derived      1987 (52 FR 11819)
                                   from burning
                                   certain oil-
                                   bearing wastes as
                                   fuel.
40 CFR 261.3(c)(2)(ii)(C).......  Wastes derived      1992 (57 FR 37263)
                                   from high
                                   temperature
                                   metals recovery
                                   of certain
                                   hazardous wastes.
40 CFR 261.3(c)(2)(ii)(D).......  Certain types of    1995 (60 FR 7848)
                                   biological
                                   treatment sludge.
40 CFR 261.3(c)(2)(ii)(E).......  Certain types of    1998 (63 FR 42184)
                                   catalyst inert
                                   support media.
40 CFR 261.3(f).................  Certain types of    1992 (57 FR 37264)
                                   debris
                                   contaminated with
                                   a hazardous waste.
------------------------------------------------------------------------

    In each of these revisions to 40 CFR 261.3, EPA considered the 
case-specific circumstances of the waste affected and, through the 
formal rulemaking process, determined that these wastes merited special 
consideration under the hazardous waste identification rules. In many 
cases, these wastes still warranted enough concern to impose specific 
management and other implementation requirements. For example, the 
solvent exclusions in 40 CFR 261.3(a)(2)(iv)(A) and (B) require that 
(1) these wastes are managed in a system the discharge of which is 
subject to regulation under either section 402 or section 307(b) of the 
Clean Water Act, and (2) the total weekly usage of these solvents 
divided by the average weekly flow of the wastewater into the treatment 
works would not exceed a specific regulatory level (either 1 ppm or 25 
ppm).
    Under today's final rule, EPA has continued the effort to reduce 
the burden from the mixture and derived-from rules where appropriate by 
excluding wastes listed solely for ignitability, corrosivity, and/or 
reactivity, once the waste no longer exhibits any of the hazardous 
waste characteristics (40 CFR 261.3(g)). We are also finalizing a 
conditional exemption for mixed waste from the mixture and derived-from 
rules, provided the mixed waste is handled in accordance with 40 CFR 
part 266, Subpart N. (40 CFR 261.3(h))
    Finally, over the past twenty years EPA has promulgated numerous 
rules establishing exclusions or conditional exemptions from the solid 
and hazardous waste definitions, and from regulatory requirements for 
particular wastes and management practices. These exemptions are part 
of EPA's overall effort to avoid unnecessary regulation of waste.
    EPA plans to continue work on other types of hazardous waste 
exemptions, including the additional targeted exemptions for certain 
categories of wastes and management practices, and the concentration-
based exemptions (HWIR exemption) discussed in the November 19, 1999 
proposal. We also plan to continue on-going efforts to streamline the 
existing delisting program.
    In regard to the specific examples of over-regulation claimed by 
one commenter (see comment # WH2P-00035, page 10), it is difficult for 
EPA to fully evaluate these cases without more specific data. For 
example, in the case of wastewaters where most of the arsenic has been 
precipitated and removed, it is not clear whether there are any other 
hazardous constituents of concern in the treatment sludge, and whether 
the residual arsenic might still pose a risk (depending on waste volume 
and management method). In the case of contaminated bricks from 
hazardous waste refractories undergoing repair, it would appear that 
the exclusion for debris [40 CFR 261.3(f)] could address this concern. 
Finally, for wastewaters that had received ethylene oxide as part of an 
emergency incident, while it is true that ethylene oxide eventually 
breaks down to ethylene glycol, this reaction is not instantaneous. 
When released into water, ethylene oxide will primarily be lost by 
three processes: volatilization, hydrolysis and biodegradation. The 
half-lives of these reactions range from a few hours to up to 20 
days.\13\ Ethylene oxide itself is toxic, and if these wastewaters were 
automatically considered non-hazardous, they could present a 
substantial risk, depending on actual concentrations and exposure 
patterns. Both low level chronic exposure and acute high levels of 
ethylene oxide can lead to a broad spectrum of neurological effects. 
Also, inhalation studies have shown that exposure to ethylene oxide can 
result in a wide range of carcinogenic effects, and NIOSH considers 
ethylene oxide to be a potential occupational carcinogen.\14\ 
Therefore, EPA does not agree that such a mixture should be 
automatically excluded from hazardous waste regulation. More 
importantly, since the purpose of this rulemaking is not to evaluate 
individual wastestreams, EPA does not believe this example demonstrates 
that the mixture and derived-from rules themselves are unnecessary as a 
general matter.
---------------------------------------------------------------------------

    \13\ Agency for Toxic Substances and Disease Registry. (1990). 
Draft Toxicological Profile for Ethylene Oxide.
    \14\ National Institute for Occupational Safety and Health. 
(1989). Ethylene Oxide Sterilizers in Health Care Facilities, 
Engineering Controls and Work Place Practices. DHHS (NIOSH) No. 89-
115.
---------------------------------------------------------------------------

    EPA understands that the RCRA regulations, in particular the waste 
identification regulations, can be difficult to understand. We have 
attempted to use plain language in drafting today's revised regulatory 
language, and will continue to make regulatory language more accessible 
to readers in the future. In addition, we believe that the mixture and 
derived-from rules are more straightforward than the alternative of 
having to evaluate each combination and permutation of

[[Page 27282]]

listed waste on a case-by-case basis. We believe this alternative would 
create uncertainty for the regulated community, state agencies, the 
public, and the courts, as various stakeholders press conflicting views 
as to whether a particular waste does or does not continue to meet the 
listing description.

VIII. What Were the Major Comments on the Revision to 40 CFR 261.3 
To Exclude Wastes Listed Solely for Ignitability, Corrosivity, and/
or Reactivity, and How Has EPA Responded to Them?

    Most commenters generally supported revisions to 40 CFR 261.3 to 
various degrees. Chemical-producing industries as well as Federal 
government agencies who commented were unanimous in support. Most 
states supported the proposed revisions to the rules to varying 
degrees. Below are summaries of the major comment issue areas for this 
proposed exclusion. For more detailed comment responses, please see 
Hazardous Waste Identification Rule: Revisions to the Mixture and 
Derived-From Rules Response to Comments Document.

A. Eligibility of Waste Listed for the Toxicity Characteristic

(1) Comments on Eligibility of Waste Listed for the Toxicity 
Characteristic
    EPA received comments from 12 commenters in response to both the 
1995 and the 1999 proposals concerning inclusion of wastes listed 
solely for the toxicity characteristic in the expanded exclusion. Of 
those comments, four were received from industry, two were from 
industry associations, four were from utility companies or utility 
company associations, one was from a Federal Government Agency, and one 
was from an industry consultant. A summary of the specific issues 
raised by commenters is provided below.
    While supporting the proposed exclusion, these commenters urged EPA 
to modify the proposal so the exclusion would apply to wastes listed 
due to any of the four characteristics, including the toxicity 
characteristic. Commenters asserted that it was not logical to limit 
the exclusion for derived-from wastes to three of the four 
characteristics, regardless of the fact that no listed wastes are 
listed solely on the basis of the toxicity characteristic. One 
commenter stated that it appears as if EPA suspects that wastes 
containing TC constituents below the toxicity characteristic are not 
really safe. A few commenters noted that in the future, wastes that may 
be listed solely for the toxicity characteristic should be eligible for 
the exclusion. Another commenter also noted that the proposed 
regulatory language does not provide for any additional hazardous waste 
characteristics that might be promulgated in the future. Commenters 
suggested that EPA replace references to ignitability, corrosivity, and 
reactivity in the proposed regulatory language for 40 CFR 261.3(g) with 
references to any characteristic of hazardous waste identified in 
subpart C, reflecting the approach and language used in the current 
mixture rule.
    Several commenters noted that EPA did not offer an explanation for 
omitting wastes listed solely because they exhibit the characteristic 
of toxicity from eligibility for the proposed exclusions that would be 
granted by 40 CFR 261.3(g). EPA did explain that, since no listings to 
date have been based on the toxicity characteristic, EPA was proposing 
to limit the new revision to the derived-from rule to wastes listed 
because they exhibit only the characteristics of ignitability, 
corrosivity, or reactivity. However, the commenters believed it is 
confusing to give no explanation for proposing the elimination of an 
existing exclusion from the mixture rule, even if no wastes now exist 
that are eligible for the exclusion. Therefore, the commenters 
recommended that the preamble for the final rule contain such an 
explanation.
(2) EPA Response to Comments on the Eligibility of Waste Listed for the 
Toxicity Characteristic
    EPA does not agree that wastes listed solely for the toxicity 
characteristic (TC) should be eligible for the exclusion. As we 
discussed in the 1995 HWIR proposal, wastes may still pose some risk 
concerns even when TC constituents are present below TC levels (60 FR 
66369, December 21, 1995).
    The hazards that the TC regulation addresses, carcinogenicity and 
chronic chemical toxicity via contaminated groundwater/drinking water, 
have fewer clear thresholds than the other characteristics. Wastes that 
exhibit the characteristics of ignitability, corrosivity or reactivity 
typically pose acute hazards which can be addressed by application of 
appropriate treatment to decharacterize the waste. For example, 
ignitable liquid waste or waste chemical oxidizers can be treated by 
combustion, and the ash treatment residue poses no ignitability threat 
to landfills. Similarly, strong acid or basic wastes, if effectively 
neutralized, generate residues that pose no threat of skin damage. 
Waste explosives or highly reactive chemicals that are denatured or 
reacted-out under controlled conditions also generate residues that 
pose no explosion or reaction threat.
    The TC chemicals have less clear thresholds below which they pose 
little or no hazard for several reasons. Toxic chemicals pose a risk 
that is typically dependent on a range of factors, and assessment of 
hazard from toxicity is much more complex, and involves many more 
variables, than assessment of hazard from the other three 
characteristics. A waste that does not exhibit the toxicity 
characteristic for a particular chemical may nonetheless pose a 
substantial hazard depending on such factors as the volume of the 
waste, the exposure route being assessed, and the amount of dilution 
and attenuation that is assumed prior to exposure. These factors, along 
with others, are taken into account in making hazardous waste listing 
determinations based on toxicity. See 40 CFR 261.11((a)(3). In 
addition, as persistent chemicals move through the environment, they 
can accumulate, posing long-term chronic risks even at levels below 
those set for the toxicity characteristic. Thus, the toxicity 
characteristic is not designed to capture all of the wastes that might 
present a substantial hazard for the TC constituents. Rather, the TC is 
designed to capture wastes that may pose a substantial hazard, without 
the need to conduct a waste-specific risk assessment. In fact, when EPA 
promulgated the TC regulation, we stated that the regulation is 
intended to identify ``* * * broad classes of wastes which are clearly 
hazardous * * *''. We also noted that ``wastes that do not exhibit the 
hazardous waste characteristics are not necessarily non-hazardous.'' 
(55 FR 11799, March 29, 1990). In identifying TC hazardous wastes as 
``clearly hazardous'' the agency was identifying a universe of wastes 
that it believed may pose high enough risk so as to always require 
classification as hazardous. In noting that non-TC wastes are not 
necessarily non-hazardous, the agency both recognized the non-threshold 
(i.e., continuous) nature of TC constituent risks, and recognized that 
wastes falling just below the TC values may pose risks that are just 
below a ``clearly hazardous'' designation, and which may sometimes 
warrant classification as hazardous. EPA has in fact listed wastes 
based on toxicity where the waste did not fail the TCLP for the 
constituent of concern. (see, for example, the final petroleum waste 
listing, 63 FR 42154 (August 6, 1998)).
    EPA's decision to not exclude wastes listed solely for the TC could 
potentially affect the regulation of certain inorganic wastes that EPA 
has recently proposed

[[Page 27283]]

to list as hazardous. (65 FR 55684, September 14, 2000). The issue had 
been purely theoretical before that point because no waste had ever 
been listed for the TC. In the inorganics listing determination 
proposal, however, EPA proposed to list baghouse filters from antimony 
oxide production for the TC. Despite the fact these wastes fail the TC 
for lead and arsenic, they are not always being managed as Subtitle C 
hazardous waste, nor are these wastes always treated to the appropriate 
LDR standards. By listing them, we would clarify their regulatory 
status. In the preamble to the inorganics listing proposal, EPA noted 
that proposed revisions to the mixture and derived-from rules did not 
include an exclusion for wastes listed for the TC (65 FR 55705). EPA 
did not receive any public comments in response to this discussion in 
the Inorganics Listing proposal.

B. Toxicity of Wastes Listed for Ignitability, Corrosivity, and/or 
Reactivity

(1) Comments on Toxicity of Wastes Listed for Ignitability, 
Corrosivity, and/or Reactivity
    EPA received two comments in response to the 1999 proposal 
concerning the potential toxicity of waste under the proposed expanded 
exclusion to the mixture and derived-from rules. One was from a waste 
management association and one from a State agency. A summary of the 
specific issues raised by commenters is provided below.
    The commenters believed that EPA must evaluate the properties 
carefully, especially the toxicity, of the 29 compounds proposed to be 
excluded. They assert that some of these wastes are acutely hazardous 
and merit a thorough review to ensure that the exclusion is 
appropriate. The waste management association noted that EPA had not 
performed an evaluation of the negative environmental impact associated 
with eliminating these codes. Ignitable, corrosive, and reactive wastes 
could contain substantial levels of toxic constituents that could be 
low enough not to exhibit a characteristic of ignitability, corrosivity 
or reactivity, yet high enough to cause environmental damage. One 
damage case or Superfund site can cause damages far in excess of the 
$4.6 million estimated savings predicted by EPA. The waste management 
association further argued that EPA's Hazardous Waste Characteristics 
Scoping Study (Nov. 15, 1996) identified numerous gaps in the current 
RCRA identification of characteristic wastes. The commenter believed 
that gaps were so serious that EPA should not be proposing to eliminate 
any listing that was based on a characteristic until the deficiencies 
identified in the 1996 Scoping Study were addressed fully. Also, EPA 
must not eliminate any listing once the characteristic is removed, 
because the underlying hazardous constituent still represents a 
substantial threat even after LDR treatment.
(2) EPA Response to Comments on Toxicity of Wastes Listed for 
Ignitability, Corrosivity, and/or Reactivity
    EPA continues to believe that wastes that were listed only for the 
characteristics of ignitability, corrosivity, and reactivity should 
become excluded once they no longer exhibit any characteristic, 
including the toxicity characteristic. While it is true that these 
wastes could contain constituents that were not considered in the 
original listing determination, EPA does not believe this possibility, 
without information demonstrating some particularized basis for 
concern, warrants continued regulation of the waste under Subtitle C 
once it is decharacterized. This is because of the unique nature of 
listings based on the three characteristics in question. (See the 
discussion, in Section VIII.A. above, regarding the differences between 
wastes listed for the toxicity characteristic and wastes listed for the 
characteristics of ignitability, corrosivity and reactivity). These 
listings are unlike toxicity-based listings, which involve development 
of detailed risk assessments and consideration of a range of technical 
factors. See 40 CFR 261.11(a)(3). In contrast, the basis for listings 
based on one of these characteristics is simply that the waste exhibits 
the relevant characteristic (see 40 CFR 261.11(a)(1)).
    Listings that are based on 40 CFR 261.11(a) criteria increase the 
clarity and certainty of the applicability of the Subtitle C system to 
these wastes. By listing the waste, EPA clarifies that it is hazardous 
without the need for a site-by-site demonstration that the waste in 
fact exhibits the characteristic, thereby simplifying implementation 
and enforcement regarding these wastes. EPA does not believe these 
listings should alter the basic principle that a characteristic waste 
should not be regulated as hazardous if it no longer exhibits the 
characteristic. Consistent with this approach, EPA provided in 1981 an 
exemption from the mixture rule for wastes listed for one of these 
characteristics that no longer exhibits the characteristic (see 46 FR 
56582, November 17, 1981). Today's rule provides a conforming change to 
the derived-from rule, which, because the 1981 rule only focused on 
mixtures, does not currently contain a comparable exemption. (see 60 FR 
66349, December 21, 1995). The same rationale also supports the 
inclusion of as-generated waste in today's rule (although, since these 
wastes were listed solely on the basis of exhibiting a characteristic, 
EPA expects these wastes to exhibit the characteristic at the point of 
generation). Thus, EPA does not believe that the possibility that these 
wastes may contain additional hazardous constituents not considered in 
the original listing justifies continued regulation of the waste.
    As stated earlier, EPA already excludes mixtures of these kinds of 
wastes, once the basis for listing these wastes has been removed. In 
addition, unlisted characteristic waste becomes non-hazardous when it 
ceases to be characteristic. Expanding the exclusion to non-mixtures 
that similarly do not exhibit the characteristic (particularly 
treatment residuals) would still be protective of human health and the 
environment. If there is any information that indicates that the 
original listing determination should have been based on toxicity 
risks, then the proper remedy is to amend the basis for listing the 
waste . The public can petition EPA to reconsider the basis for listing 
any such waste .
    In regard to the toxicity of the listed chemicals themselves, EPA 
has examined the most recent toxicity data in IRIS concerning the 
chemicals in the 29 wastes listed solely for a characteristic, and does 
not believe these chemicals present a particular basis for concern. We 
found that fourteen of the chemicals have RfD's or RfC's available in 
IRIS. (This includes the eight F003 solvents discussed below--see 
Section VIII.C. of the preamble). EPA used these RfCs and RfDs to 
calculate conservative screening-level health-based numbers (HBN) for 
those chemicals, and compared them to the relevant Universal Treatment 
Standards (UTS) these chemicals would need to meet under Land Disposal 
Restrictions, in those cases in which numerical standards were 
available. For most of those chemicals, the relevant UTS standards are 
much lower than the conservative health-based numbers calculated for 
water and soil ingestion pathways. As discussed in Section VIII.C 
below, the level for one of the chemicals, n-butyl alcohol, is not 
significantly higher. Therefore EPA believes that excluding wastes that 
have

[[Page 27284]]

been listed solely for a characteristic of ignitability, corrosivity, 
or reactivity, when they have been decharacterized (i.e., exhibit none 
of the four hazardous waste characteristics), is protective of human 
health and the environment. However, in the future, if additional 
information becomes available, we may decide to reconsider the basis of 
listing for one or more of these wastes.

C. Eligibility of F003 Solvents for This Exclusion

(1) Comments on Eligibility of F003 Solvents for This Exclusion
    EPA received comments from 17 commenters in response to the 1995 
and 1999 proposals concerning the inclusion of F003 solvents in the 
expanded exclusion to the mixture and derived-from rules. Of those 
comments, five were from State Agencies, three were from utility 
companies or associations, four were from industries, two were from 
Federal Agencies, two were from waste management associations, and one 
was from an industry association. A summary of the specific issues 
raised by commenters is provided below.
    About two-thirds of the commenters supported including F003 wastes 
in the proposed exclusion. However, one industry noted that this 
proposed revision would have little effect beyond eliminating the 
derived-from rule for a small number of wastes. Many commenters noted 
that if the solvent contained, before use, one or more of the toxic 
solvents specifically listed in F001, F002, F004, or F005, at 10 
percent or more by volume, it would be regulated as that waste code. 
Therefore a blanket exclusion for all categories of F003 is appropriate 
because toxics, when present, will be addressed under other applicable 
waste codes. One State and two Federal commenters stated that any toxic 
solvents contained in an F003 spent solvent blend would not escape 
proper treatment because of the land disposal restrictions (LDR) 
program. They also noted that solvent mixtures/blends meeting the F003 
listing description and containing a certain percentage of toxic 
solvents also will carry the waste code F001, F002, F004 and/or F005 
and therefore, be subject to treatment requirements under the LDR 
program.
    Four commenters did not support including F003 in the proposed 
exclusion. They argued that the listing description for F003 contains a 
reference to other solvent wastes (F001, F002, F004, or F005) that are 
listed for toxicity. Therefore, ignitability was not the only 
characteristic of concern. In addition, certain F003 solvents 
themselves may also be toxic, upon consideration of new data developed 
since 1985. Specifically, the commenter cited a National Toxicology 
Program, National Institutes of Environmental Health Sciences, 
Management Statistics Report dated January, 1999 on the carcinogenicity 
of ethylbenzene (an F003 waste).
    In addition, one State noted that in the April 30, 1992 proposal to 
revise the Hazardous Waste Identification Rule, EPA was considering a 
separate rulemaking to modify the basis for listing F003 and other 
wastes listed solely for a characteristic because of concerns about 
toxicity and/or carcinogenicity. If the chemicals in these wastes are 
either toxic or carcinogenic according to EPA's own determinations, 
they should be identified as such in 40 CFR part 261, subpart D.
    Commenters also argued that F003 wastes ``often'' contain toxic 
constituents other than the solvents themselves. One commenter noted 
that EPA states in 50 FR 53317 (December 31, 1985) ``In fact, solvents 
become spent when they have become contaminated with other materials, 
(i.e., heavy metals or toxic organic compounds) and must be disposed, 
reprocessed or reclaimed.'' EPA further states `` * * * since spent 
solvents reasonably are likely to contain other toxicants at levels of 
regulatory concern, and since we have not evaluated those wastes for 
these toxicants, we believe it inappropriate to remove these solvents 
from the hazardous waste list.'' In addition, the waste management 
association commenter argued that as part of the economic impact 
analysis associated with the 1999 HWIR proposal, there have been 51 
different hazardous constituents associated with the F003 waste code. 
The commenter believed that if EPA lacked toxicological data on any of 
these constituents, then F003 could not be eligible for the exclusion 
once the ignitability characteristic was removed and the waste 
exhibited no other hazardous waste characteristics.
(2) Response to Comments on Eligibility of F003 Solvents for This 
Exclusion
    EPA agrees with those comments that support F003 waste remaining 
eligible for this exclusion. Because F003 waste that contains 10% or 
more of the other F-listed solvents (F001, F002, F004, and F005) would 
also bear those waste codes, such wastes would not be eligible for the 
exclusion. The exclusions applies only to F003 wastes that do not 
contain 10% or more of these other solvents.
    EPA is aware of the recent carcinogenicity study (referenced in the 
public comments) that was performed by the National Toxicology Program 
on ethylbenzene. Ethylbenzene is included in the Agency's on-going 
Integrated Risk Information System (IRIS) project (63 FR 68285, 
December 10, 1998). A focus of the IRIS project is to update selected 
chemical assessments by incorporating new scientific information and 
methods. The IRIS project consists of a process that determines the 
Agency's consensus position on the potential adverse health effects 
that may result from chronic or lifetime exposures to environmental 
contaminants. The carcinogenicity study on ethylbenzene, together with 
any other recent toxicological data, will be evaluated by the Agency as 
part of this process. Until that evaluation is completed, EPA does not 
believe it is appropriate to draw regulatory conclusions based on the 
referenced study.
    With respect to the commenters' more generalized concerns about the 
possibility of toxic constituents in F003 waste, as explained above, 
EPA does not believe this possibility justifies the continued 
regulation of a waste that was listed for the sole reason that it is 
ignitable, where the waste is no longer ignitable and exhibits no other 
hazardous waste characteristic. F003 waste is unique among the listed 
solvents: the other listed solvents were listed on the basis of 
toxicity. F005 solvents were listed for both ignitability and toxicity. 
In fact, EPA decided to move two listed solvents (methanol and methyl 
isobutyl ketone) that were originally proposed to be regulated under 
the F005 listing to the F003 listing because EPA determined that they 
did not pose a significant toxicity risk, although they are highly 
flammable (45 FR 74884, November 12, 1980).
    Since then, EPA has analyzed the toxicity risks that might be posed 
by F003 solvents when de-characterized. The Agency has researched the 
most recent data concerning the F003 solvents in the IRIS data base. 
None of the solvents in the listing are classified as carcinogens, but 
eight of the nine possess reference concentrations (RfC) and oral 
reference doses (RfD) for non-cancer risk. EPA used these RfCs and RfDs 
to calculate conservative screening-level health-based numbers (HBN) 
for those chemicals, and compared them to the relevant Universal 
Treatment Standards (UTS) these chemicals would need to meet under Land 
Disposal Restrictions. For seven of the eight chemicals (including 
ethylbenzene) the relevant UTS standards are much lower than the

[[Page 27285]]

conservative health-based numbers calculated for water and soil 
ingestion pathways. The health-based number for the remaining chemical, 
n-butyl alcohol, is only slightly lower than the UTS standard (3.3 mg/L 
water ingestion HBN vs 5.6 mg/L wastewater UTS).\15\ Given the fact 
that the health-based numbers are conservative screening numbers, EPA 
does not believe this difference is of concern. Therefore EPA remains 
confident that excluding ignitable F003 solvents, when they have been 
decharacterized, is protective of human health and the environment.
---------------------------------------------------------------------------

    \15\ For the water ingestion pathway, EPA assumed a 71.8 kg 
adult with a 2.3 L/day intake (90th percentile), 350 days/yr 
frequency. For the soil ingestion pathway, EPA assumed a 16.6 kg 
child with 400 mg/day intake (upper percentile), 350 days/yr 
frequency. For more information, please see U.S. EPA Analysis of 
Chemicals in Wastes Listed for Ignitability, Corrosivity, or 
Reactivity memorandum to the docket from David Cozzie, Office of 
Solid Waste, November 22, 2000.
---------------------------------------------------------------------------

    Commenters also claimed that F003 solvents, because they are 
general use solvents, can carry with them various constituents other 
than the solvents themselves, and that this was a reason for listing 
the F003 solvents in the first place (see 50 FR 53317, December 31, 
1985). EPA acknowledges that in the 1985 solvents final rule, we noted 
that additional toxic contaminants would likely be present in the spent 
solvent. We also stated, however, that we did not evaluate F003 wastes 
for other toxic constituents that could be present at levels of 
regulatory concern. Therefore, toxicity was a not a basis for listing 
F003 waste.
    When the F003 listing was finalized in 1985, because it was listed 
solely for ignitability, mixtures of F003 waste and solid waste were 
eligible for the exemption for mixtures of waste listed for a 
characteristic that no longer exhibit any characteristic of hazardous 
waste. Expanding the exclusion to non-mixtures that similarly do not 
exhibit any characteristic would still be protective of human health 
and the environment. We do not think it makes sense to continue the 
anomaly of retaining regulation for non-mixtures of F003 wastes based 
on toxicity concerns when we have no record basis to support regulation 
for toxicity. Today's exclusion is also consistent with the approach 
taken in EPA's decision not to list 14 spent solvent wastes, in which 
EPA declined to focus on any toxic constituents other than those in the 
solvents themselves, despite the likelihood of other toxic constituents 
in the spent solvent waste. (63 FR 64372 (Nov. 19, 1998).\16\
---------------------------------------------------------------------------

    \16\ EPA's determination was upheld at EDF v. EPA, 210 F.3d 396 
(D.C. Cir. 2000).
---------------------------------------------------------------------------

D. Applicability of Land Disposal Restrictions (LDRs) to Excluded 
Wastes

(1) Comments on Applicability of Land Disposal Restrictions (LDRs) to 
Excluded Wastes
    EPA received comments from 20 commenters in response to both the 
1995 and the 1999 proposals concerning the applicability of LDRs to 
excluded wastes. Of those comments, eight were received from 
industries, four were from industry associations, two were from Federal 
Government Agencies, two were from State Agencies, one was from a 
consultant, one was from a waste management association, one was from a 
waste management company, and one was from an individual commenter. A 
summary of the specific issues raised by commenters is provided below.
    Several commenters supported the EPA's proposed revision to the 
mixture and derived-from rules provided that the excluded waste meets 
land disposal restriction (LDR) requirements. One industry association 
noted that LDR standards assure that the waste is well treated. One 
State Agency believed that having similar wastestreams comply with the 
same requirements will achieve regulatory consistency as well as 
protection of human health and the environment.
    Several commenters supported EPA's proposed revisions to the rules 
but did not support meeting LDR requirements. One industry commenter 
stated that applying LDRs to a waste which is excluded because it no 
longer meets the hazardous waste criteria is unnecessarily burdensome, 
costly and is a contradiction of the RCRA program requirements.
    Two commenters said that the applicability of LDRs to both 
wastewater and nonwastewater forms of wastes should be both clear and 
identical. They felt that there is no justification for managing these 
wastes inconsistently.
    Several of the comments dealt with whether excluded waste would 
need to be treated to meet LDR treatment standards for all underlying 
hazardous constituents (UHCs) under the existing rules. They felt that 
EPA should clarify that it did not intend to revise application of the 
current LDR rules without any discussion of why such a change would be 
necessary. One commenter emphasized that EPA has not provided a 
compelling case for requiring testing for UHCs or a clear methodology 
for implementing the requirements that are proposed. They stated that 
since these wastes are listed, generators have not been required to 
obtain information on underlying hazardous constituents. Obtaining this 
information would pose an undue burden for the generator, and they 
requested clarification on who would be responsible for verifying 
whether the waste in question meets the condition of the exclusion: the 
generator or the facility receiving the excluded waste.
    Two industry association commenters referenced the Land Disposal 
Program Flexibility Act of 1996 (LDPFA) and its relationship to the 
proposed exclusion. Under LDPFA, solid wastes identified as hazardous 
based solely on a characteristic, are not prohibited wastes under the 
Land Disposal Restrictions program if they are managed in certain 
systems including a treatment system that subsequently discharges into 
waters of the United States pursuant to a CWA permit. The commenters 
further requested that EPA revise its proposed language modifying the 
mixture rule for wastes in proposed 40 CFR 261.3(a)(2)(ii) so that the 
land disposal restrictions program does not apply to wastes that are 
not prohibited. They argued that this revision is crucial to maintain 
the status quo for managing wastes listed solely for a characteristic 
in land-based units. Imposing the LDR program on such wastes would put 
many surface impoundments out of compliance because they are managing 
decharacterized listed wastes in land-based units that do not meet 
RCRA's minimum technology requirements.
(2) EPA Response to Comments on Applicability of Land Disposal 
Restrictions (LDRs) to Excluded Wastes
    In proposing to expand the current exclusion for waste listed 
solely for a characteristic, EPA did not intend to change the way land 
disposal restrictions (LDRs) apply to the excluded waste. EPA agrees 
with those comments that support the continued application of LDR 
requirements to mixture and derived-from wastes listed solely for a 
characteristic of ignitability, corrosivity, or reactivity after they 
have become excluded. We are not imposing any new LDR requirements in 
this rule.
    We agree that the treatment standards for UHC's do not apply in all 
cases, and have not changed the applicability of these requirements. In 
general, wastes that are both listed as hazardous waste and exhibit a 
characteristic only need to meet the treatment standard for the listed 
waste code. (40 CFR 268.9(b)). An exception occurs when the treatment 
standard for the listed waste code does not include a standard for the 
constituent that causes the waste to exhibit the characteristic. In 
this case, the waste must meet the treatment standards for all 
applicable listed and characteristic waste codes.

[[Page 27286]]

    EPA disagrees with the comment that LDRs for wastewaters and 
nonwastewaters should be identical. We continue to support the existing 
different treatment standards for wastewaters and nonwastewaters. Such 
differences are based on waste treatability and differences in the Best 
Demonstrated Available Technology applicable to the waste.
    Today's rule also does not broaden the applicability of LDRs. The 
revised language to 40 CFR 261.3 (g)(3) states, ``Wastes excluded under 
this section are still subject to part 268 of this chapter (as 
applicable), even if they no longer exhibit a characteristic at the 
point of land disposal.'' When the requirements of 40 CFR part 268 
would not otherwise apply to a waste (for example, during treatment of 
certain characteristic wastes in a land-based unit), today's rule does 
not change that fact. In the case of wastes listed solely for 
ignitability, corrosivity, and reactivity that do not exhibit a 
characteristic at the point of generation, these wastes are considered 
to never have been hazardous and are not subject to 40 CFR part 268.

E. Applicability of Contained-In Policy to Excluded Wastes

1. Comment on Applicability of Contained-In Policy to Excluded Wastes
    One commenter, the Department of Defense (DoD), requested that EPA 
clarify the interaction of the contained-in policy to the RCRA wastes 
that are listed solely for ignitability, corrosivity, and/or reactivity 
characteristics.
2. EPA Response to Comment on Applicability of Contained-In Policy to 
Excluded Wastes
    The contained-in principle is the basis for EPA's longstanding 
interpretation regarding application of RCRA Subtitle C requirements to 
mixtures of contaminated media and hazardous wastes. Under the 
``contained-in'' policy, EPA requires that soil (and other 
environmental media) be managed as hazardous wastes so long as they 
contain listed hazardous waste or exhibit a characteristic of hazardous 
waste. EPA's application of the ``contained-in'' policy to regulate 
media containing hazardous waste was upheld by the D.C. Circuit Court 
of Appeals in Chemical Waste Management v. EPA, 869 F2d 1526, 1539-40 
(D.C. Cir. 1989). See the LDR Phase IV final rule 63 FR 28556, 28621 
(May 26, 1998) for a detailed discussion of the contained-in policy and 
the Agency's reason, at the time, not to codify the contained-in policy 
for contaminated soil.
    Today's final rule does not directly affect the implementation of 
the contained-in policy. However, wastes that are contained in 
contaminated media are eligible for the 40 CFR 261.3(g) exemption for 
wastes listed solely for a characteristic. Therefore, under today's 
final rule, contaminated media that contain a waste listed solely for a 
characteristic would no longer need to be managed as hazardous waste 
when it no longer exhibits a characteristic. However, consistent with 
the regulation of other decharacterized waste (and decharacterized 
contaminated media), it may remain subject to LDR requirements. (The 
final rule, by providing that wastes excluded under this section are 
subject to LDRs ``as applicable,'' applies the current rules regarding 
LDR applicability to soil containing hazardous waste. See, 40 CFR 
268.49. For a detailed discussion of this subject, see 63 FR 28556, 
28617 (May 26, 1998).)

IX. What Were the Major Comments on the Revision to 40 CFR 261.3 
for Mixed Wastes, and How Has EPA Responded to Them?

A. 1999 Proposed Revision to 40 CFR 261.3 for Mixed Waste

    In the 1999 proposal, EPA proposed a change to 40 CFR 261.3 that 
would exclude certain eligible mixed wastes (i.e., wastes that are both 
hazardous and radioactive) when they met the conditions outlined in the 
proposed 40 CFR part 266, Subpart N, which appeared in a separate 
Federal Register Notice. 64 FR 63464 (Nov. 19, 1999). EPA received 
comments from nine commenters in response to the 1999 HWIR proposal 
concerning the conditional exclusion from the mixture and derived-from 
rules for mixed waste. The commenters supported EPA's proposed 
conditional exemptions for low-level mixed waste (LLMW). Many of these 
commenters believed that such an exemption was implicit in the mixed 
waste proposal and necessary for the proposed mixed waste conditional 
exemptions to function effectively. Many of these commenters also noted 
that EPA's proposal would help eliminate much of the current regulatory 
overlap associated with LLMW. One commenter added that since the 
implementation of LLMW management under RCRA, it had been difficult to 
find treatment/disposal capacity for its limited quantities of mixed 
waste, and the proposal would improve safety, efficiency, cost and 
timeliness of LLMW management. Several commenters encouraged EPA to 
expedite its implementation.
    However, two commenters (both Federal agencies) were concerned with 
the proposed regulatory language for implementing a conditional 
exemption from the mixture and derived-from rules for mixed waste. The 
commenters believed it would be more appropriate to pursue regulatory 
relief for low-level mixed waste (LLMW) via the standards proposed for 
40 CFR part 266, Subpart N rather than within the definition of 
hazardous waste in 40 CFR 261.3. This proposed exemption within 40 CFR 
261.3 would provide an inconsistency in the application of the MDF 
rules between wastes mixed with or derived-from the treatment of 
hazardous wastes and wastes mixed with or derived-from the treatment of 
LLMWs. The commenters noted that the proposed regulation for the 
transportation/disposal conditional exemption for mixed waste, section 
266.305, exempts the waste from certain RCRA requirements (provided 
specified conditions are met), but does not exempt the waste from the 
definition of hazardous waste.
    EPA appreciates the support expressed for the conditional exemption 
for mixed waste mixtures and derived-from wastes. In response to the 
apparent confusion about how the proposed regulatory language applies 
to these conditionally exempt mixed wastes, EPA has created a new 
section to 40 CFR 261.3, section (h), which more carefully explains how 
the definition of hazardous waste interacts with the mixed waste 
conditional exemption.

B. 1995 Comments on Conditional Exemptions for Mixed Waste

    In EPA's 1995 HWIR proposal, we included a discussion of possible 
conditional exemptions for mixed wastes based on EPA's HWIR modeling, 
or on other conditions outlined in a proposal developed by the 
Department of Energy (DOE). EPA received comments from 45 commenters 
regarding this discussion, many of whom urged EPA to separate mixed 
waste from the HWIR rulemaking. DOE has since withdrawn its proposal, 
and EPA has developed a separate mixed waste exemption, which is 
published elsewhere in today's Federal Register. For a more detailed 
explanation of all the mixed waste comments submitted as part of the 
HWIR rulemakings, and EPA's response to those comments please see 
Hazardous Waste Identification Rule: Revisions to the Mixture and 
Derived-From Rules Response to Comments Document.

[[Page 27287]]

X. What Were the Major Comments on the Recommendations Submitted by 
the Chemical Manufacturers Association (CMA), and How Has EPA 
Responded to Them?

    In August 1999, EPA received a paper from the Chemical 
Manufacturers Association (CMA) \17\ describing five regulatory options 
for revising the mixture and derived-from rules. CMA forwarded these 
options seeking regulatory relief for some specific high-volume wastes 
that they believe are low-risk and feel that EPA could propose to 
exclude with very little delay. Although we did not have sufficient 
time to analyze these options in detail, we included a discussion of 
them in the 1999 HWIR notice to allow for public comment. Below is a 
short description of each option, a summary of the comments on the 
option, and EPA's response to the comments.
---------------------------------------------------------------------------

    \17\ CMA has since changed the name of the organization to the 
American Chemistry Council (ACC).
---------------------------------------------------------------------------

    EPA is currently developing proposals related to two of the 
suggestions that we believe to be the most promising and 
straightforward to address: expanding the current headworks exclusion 
and excluding certain combustion residues. (see Sections X.A. and X.D. 
respectively). We are also considering additional proposals on the 
other suggestions, but we believe more analysis would first be 
necessary to decide how to address specific issues raised in the public 
comments. In addition, we will consider whether other opportunities 
exist for exempting low-risk waste from full Subtitle C regulation, 
including additional targeted exemptions and efforts to streamline the 
delisting program.

A. Expanding the Current Headworks Exclusion

    One option involves an expansion of the current ``headworks'' 
exclusion in 40 CFR 261.3(a)(2)(iv)(A) and (B). The headworks exclusion 
excludes from the mixture rule wastewaters containing small quantities 
of particular F-listed solvents, based on the mass-balance flow of 
these solvents through the headworks of industrial wastewater treatment 
systems. CMA's options paper requests that this exclusion be amended in 
three ways.
    First, CMA's suggested revision would allow direct monitoring of 
the actual concentration of spent solvents in untreated wastewater to 
demonstrate compliance. The current requirement is to perform a weekly 
mass balance of the solvents entering the system. Losses due to 
volatilization must be counted in the mass balance determination under 
the current system. We note that CMA's suggested wastewater monitoring 
would provide accurate data at the point the wastewater enters the 
treatment system, but the losses due to volatilization would not be 
counted in this approach.
    Second, under CMA's suggested revisions, benzene, 2-ethoxyethanol, 
2-nitropropane, and 1,1,2-trichloroethane would be incorporated into 
the list of chemicals for exclusion. These four chemicals were added to 
the 40 CFR 261.31 list of spent solvents in 1986 but the exclusion does 
not currently include these chemicals.
    Third, under CMA's suggested revisions, multi-source leachate 
(F039) derived solely from the disposal of the spent solvents listed in 
40 CFR 261.31 would be eligible for the exclusion.
(1) Summary of Comments on Expanding Headworks Exclusion
    EPA received comments from 13 commenters in response to the 
discussion on expanding the headworks exclusion. Of those comments, two 
were received from industry, three were from industry associations, 
three were from utility companies or utility company associations, 
three were from State Agencies, one was from a Federal Government 
Agency, and one was from a waste management association. A summary of 
the specific issues raised by the commenters is provided below.
    One state commenter noted that CMAS's suggested exclusion does not 
account for volatilization, an important factor considering the 
solvents involved, if the wastewater treatment system is not actually 
subject to Clean Air Act controls. In addition, they noted that CMA's 
suggested exclusion addresses whether and how RCRA should be modified 
in the wastewater treatment context, and they felt that this is a 
matter that could be addressed comprehensively following the completion 
of the surface impoundment study.\18\ One waste management association 
commenter stated it was not clear what the potential environmental 
impact would be of expanding this exclusion to additional chemicals.
---------------------------------------------------------------------------

    \18\ Note: EPA's surface impoundment study was completed March 
2001. See U.S. Environmental Protection Agency. Industrial Surface 
Impoundments in the United States. EPA530-R-01-005. Washington, D.C. 
March 2001.
---------------------------------------------------------------------------

    The rest of the commenters supported the CMA's recommendations for 
specific modifications to the mixture rule to expand the headworks 
exclusion in 40 CFR 261.3(a)(2)(iv)(A) and (B). Commenters noted that 
subsequent to the original headworks exclusion, additions were made to 
the F code solvent listings, but the corresponding changes were not 
made to the list of solvents in the headworks exclusion. For 
consistency, benezene, 2-ethoxyethanol, 2-nitropropane and 1,1,2-
trichloroethane should be added to the list of solvents allowed under 
the headworks exclusion. One State added that the circumstances and 
reasoning that EPA used to support finalizing the original exclusion 
remain valid for these four solvents. Commenters also noted that they 
believed EPA would determine the appropriate headworks concentration 
(i.e., either 1 part per million or 25 parts per million). Also, it is 
appropriate, practical, and economical for a generator to manage small 
amounts of spent solvent wastes in a wastewater treatment system 
subject to regulation under sections 402 and 307 (b) of the Clean Water 
Act.
    Nine of the commenters supported the use of direct monitoring of 
the actual concentration of spent solvents in untreated wastewater to 
demonstrate compliance with the headworks exclusion. Several commenters 
believed direct monitoring would facilitate documentation of 
compliance. A Federal commenter noted that the suggested changes would 
provide accurate data at the point the wastewater enters the treatment 
system, but still would allow generators who rarely discharge solvents 
into their wastewater systems to use the current method for verifying 
compliance. Several commenters believed that the mass-balance approach 
gives rise to a number of problems due to the varying degrees of 
precision in the underlying measurements and, therefore, deters use of 
this exclusion. Instead, direct sampling and analysis methods are much 
more straightforward to implement and would provide more accurate 
information about what actually is being discharged to treatment 
systems. A State commented that direct monitoring provides the most 
definitive information on the concentration levels of hazardous 
constituents in a waste. Direct monitoring would allow generators to 
apply the exclusion to its full intended regulatory limit. An industry 
commenter recommended that compliance with the regulatory levels be 
measured on a rolling average basis since flows may be variable. 
Several commenters noted that they do not believe that direct 
monitoring would encourage volatilization. They noted that EPA did not 
state directly that the current measurement scheme needed to account 
for volatilization when the headworks exclusion was finalized and it is 
not part of the current regulatory

[[Page 27288]]

language. However, these comments recognized that over the years, EPA 
has explained in preamble language and interpretive letters that it 
considered accounting for volatilization losses to be necessary to 
prevent facilities from volatilizing solvents in order to be eligible 
for the exclusion. In the years subsequent to the statement, EPA has 
issued a number of regulations addressing air emissions of organics, 
including the listed solvents. Because EPA has addressed these 
potential air emissions by regulations which focus specifically on 
these emissions, the commenters felt that there is no need for the 
headworks exclusion to have to account for them as well.
    One State commenter did not support the inclusion of multi-source 
leachate (F039) in the headworks exclusion, even though the leachate 
might be derived from the disposal of solvent wastes. The commenter 
noted that leachate might contain any variety of hazardous 
constituents, due to the presence of characteristic wastes or non-
hazardous wastes. The commenter further noted that it would be 
difficult to determine whether the headworks exclusion, if modified in 
this manner, would protect human health and the environment 
sufficiently. The commenter did state that if the discharge is 
regulated under the Clean Water Act (CWA), this may provide a 
reasonable amount of assurance with respect to exposure paths, relating 
to the wastewater discharge.
    Six of the commenters supported extending the exclusion to multi-
source leachate (F039) derived solely from the disposal of the spent 
solvents in 40 CFR 261.31. A Federal commenter noted that in many 
cases, leachate is contaminated with barely detectable concentrations 
of F-listed solvents, yet the leachate still is classified as hazardous 
waste. By allowing the wastewater to be discharged for treatment to a 
wastewater treatment or pre-treatment system regulated under the CWA, 
EPA would encourage remediation by lowering treatment costs. The 
commenter also stated that EPA must believe that the 1 ppm/25 ppm 
concentration limits established under the existing rules are 
protective of human health and the environment, so extending those 
limits to wastes derived from the land disposal of certain listed 
solvents should be adequately protective.
    Several commenters noted that the advent of the multi-source 
leachate waste code simplified some hazardous waste management by 
applying the single listing code to hazardous waste leachate. However, 
this streamlining did create some unintended consequences. Leachate 
generated solely from F001-F005 solvents no longer qualified for the 
headworks exclusion, even though the composition of the leachate was 
virtually identical to dilute non-leachate F001-F005 streams. 
Therefore, even though F039 leachate derived solely from F001-F005 
wastes are exactly the same in chemical composition as the wastes from 
which they are derived, they cannot be treated in the same treatment 
train. They must be segregated and handled in separate tank-based 
systems or shipped off site for treatment and disposal causing 
additional cost but providing no additional environmental protection. 
One industry commenter recommended that EPA issue a technical 
correction or clarification notice with or before promulgating the 
final HWIR rule to address this problem. Under CMA's recommendation, 
the headworks exclusion rationale for the solvent wastes from ongoing 
production processes would be applied equally to solvent wastes 
leaching from a landfill. Both are treated equally well in the 
wastewater treatment plant at these low concentrations, so there is no 
justification for regulating them differently.
(2) EPA Response to Comments on Expanding the Headworks Exclusion
    EPA agrees that there is merit in proposing to expand the current 
exclusions in 40 CFR 261.3(a)(2)(iv)(A) and (B) (the ``headworks'' 
exclusion) to include the four solvents listed in 1986: benzene, 2-
nitropropane, 2-ethoxyethanol, and 1,1,2-trichloroethane, and we are 
currently developing a proposal on such an expansion. In the proposal, 
EPA will take into account the issues raised by the commenters, 
including environmental impacts of the expanded exclusion, and the use 
of any available surface impoundment study data. In the meantime, we 
welcome any data or additional feedback from the public on this topic.
    We will also evaluate in this proposal the issue of measurement 
versus mass balance calculation as a part of the implementation of the 
headworks rule. EPA agrees that in the past 20 years, significant new 
Clean Air Act regulations have come into effect that may address some 
of the concerns about deliberate volatilization. In developing a 
proposed revision to the monitoring requirements for the headworks 
rule, we would take into account the issue raised by the commenters, 
including the issues concerning volatilization. We welcome any 
additional data the public has to support such a change.
    EPA is also interested in possible applications in which solvent-
only landfill leachate may be sent to a wastewater treatment facility. 
We are concerned, however, about possible difficulties in determining 
whether a landfill has received only solvent wastes. As part of the 
investigation, EPA would need more information characterizing possible 
``solvent waste only'' landfills. We welcome any additional data the 
public has on these landfills.

B. Excluding Hazardous Waste Leachate

    Another of the suggested regulatory options involves leachate 
derived from the land disposal of listed hazardous waste which is 
subsequently managed in a system regulated under the Clean Water Act. 
CMA argues that the leachate is both physically and chemically 
dissimilar from the wastes that were originally listed. Under the 
option presented, leachate would not be hazardous, even when generated 
from the treatment, storage or disposal of hazardous waste, unless it 
exhibited one or more of the hazardous waste characteristics of 40 CFR 
Part 261, Subpart C.
(1) Comments on Excluding Hazardous Waste Leachate
    EPA received comments from eight commenters in response to 
excluding leachate. Of those comments, three were received from 
industries, one was from an industry association, three were from State 
Agencies, and one was from a waste management association. A summary of 
the specific issues raised by commenters is provided below.
    The waste management association did not support the exclusion, 
noting that treatment tanks that are part of a Clean Water Act (CWA) 
system already are conditionally exempt. Thus, it was not clear to the 
commenter why a more expansive exclusion was advisable, particularly 
because leachate from hazardous wastes ``may often contain toxic 
constituents that are not subject to NPDES discharge limits or water 
quality standards.'' Also, one State did not support the exclusion 
noting that many organics of concern are not covered by the toxicity 
characteristic. Furthermore, the State commenter believed that it would 
be inappropriate to exclude these wastestreams without examining the 
results of the surface impoundment study, particularly without any 
supporting data on the physical/chemical properties of the leachate and 
its associated risks. Finally, these State comments claimed that there 
is no generic way to tell if these leachates will pose a problem. They 
could be very

[[Page 27289]]

different from unit to unit depending upon what type of waste has been 
placed in the unit. The commenter also felt that there could be an air 
emission problem or the leachate could cause the sludge to become 
hazardous. Instead, the State commenter thought industries should go 
through a case specific delisting for these wastes.
    One State commenter did not understand CMA's proposal to exclude 
leachate from the derived-from rule. Currently, F039 leachate waste is 
subject to Part 268 land disposal restriction requirements and could be 
treated onsite in a tank or container within 90 days of generation 
without a permit. If this treated waste was an industrial wastewater 
discharge that was a point source discharge subject to regulation under 
section 402 of the Clean Water Act, it would be eligible for the 
261.4(a)(2) exclusion. In that case the wastewater would not be a solid 
waste. The State wondered if CMA was proposing that F039 be exempt from 
LDR requirements. If that was the case, the State did not support such 
a recommendation.
    One State commenter stated that there may be merit in excluding 
leachate resulting from the land disposal of a listed hazardous waste 
when the leachate is subsequently managed in a wastewater treatment 
system regulated under the CWA. However, to make a definitive decision, 
the State expressed a need to evaluate constituent concentration data, 
current management practices, environmental injury cases caused by the 
residues, and whether the residues commonly exhibit a hazardous waste 
characteristic. Since (1) the leachate is generated from landfills 
where only treated hazardous wastes are disposed, and (2) bonafide 
treatment has occurred and the residues are physically and/or 
chemically different from the hazardous wastes they were generated 
from, the State believed it was appropriate to view the residues as 
newly generated wastes and impose RCRA regulation only if the waste 
exhibited a hazardous waste characteristic.
    The rest of the commenters believed that EPA should consider 
leachate from hazardous waste landfills to be a newly generated waste 
rather than derived-from waste. As a newly generated waste, it would be 
subject to regulation if it failed one or more hazardous waste 
characteristics, but would no longer be subject to hazardous waste 
regulation solely because the landfill accepted listed hazardous 
wastes. Several commenters noted that most POTWs would not accept 
direct discharges of listed hazardous waste, even if the leachate met 
all applicable effluent guidelines and other standards. As a result, 
several commenters noted that they must use costly and unnecessary 
incineration or other treatment at off-site facilities. In addition, 
the transportation and management from sending the wastes off-site 
actually may increase environmental risks and energy usage relative to 
the protective and cost-effective management in industrial wastewater 
systems. Several commenters noted that both landfills and land 
treatment units, as defined by RCRA, generate a leachate when 
constructed with a bottom liner. Leachate from either type of unit 
should qualify for the exclusion so long as it did not fail for a 
hazardous characteristic and the wastewater treatment system receiving 
the leachate was subject to regulation under the CWA. Two commenters 
also recommended as an alternative to considering leachate from 
hazardous waste landfills to be a newly generated waste, that EPA make 
it eligible for the headworks exclusion.
(2) EPA Response to Comments on Excluding Hazardous Waste Leachate
    At this time, EPA is still considering the suggested regulatory 
exclusion for leachate derived-from landfilled hazardous waste as well 
as other specific exemption options, but we first need to evaluate 
several important issues. As noted in the comments, most hazardous 
waste leachate is regulated under a separate waste code, F039. To date, 
we have received no information that would cause us to reconsider that 
listing, although we would welcome any data that might be helpful in 
such a re-evaluation. However, in the most recent EPA study of landfill 
leachate characteristics (65 FR 3007, January 19, 2000), we found 
considerable differences between the leachate samples from hazardous 
and those from non-hazardous landfills in both numbers of constituents 
of concern and their concentrations. Hazardous waste landfill leachate 
contained a greater number of constituents than non-hazardous waste 
landfill leachate, and constituents found in both hazardous and non-
hazardous waste landfill leachate were generally present in hazardous 
waste landfill leachate at concentrations an order of magnitude higher 
than those found in non-hazardous waste landfill leachate.\19\ As noted 
in the comments, these pollutants can include many organic hazardous 
constituents not covered by the Toxicity Characteristic. Absent a risk 
assessment, it is not possible to determine whether the levels of these 
constituents pose unacceptable risk. However, the presence of these 
constituents is a strong indication that more study would be needed 
before developing an exemption for hazardous waste leachate.
---------------------------------------------------------------------------

    \19\ Development Document for Final Effluent Limitations 
Guidelines and Standards for the Landfills Point Source Category, 
EPA-821-R-99-019, U.S. EPA, January 2000.
---------------------------------------------------------------------------

C. Excluding Hazardous Waste Aggressive Biological Treatment Residues

    Another suggested regulatory option involves excluding residues 
from the biological treatment of listed hazardous wastewaters. CMA 
argues that theses wastes are both physically and chemically dissimilar 
from the wastes that were originally listed. In addition, CMA notes 
that biological treatment can greatly reduce or eliminate organic 
chemicals. Under the options presented in CMA's discussion papers, 
these wastes would not be hazardous, even though they are generated 
from the treatment, storage or disposal of hazardous waste, unless they 
exhibit one or more of the hazardous waste characteristics of Subpart C 
of 40 CFR part 261.
(1) Comments on Excluding Residues From Aggressive Biological Treatment 
of Hazardous Waste
    EPA received comments from 10 commenters in response to the CMA 
recommendation to exclude aggressive biological treatment residues from 
the derived-from rule. Of those comments, four were received from 
industries, two were from industry associations, three were from State 
Agencies, and one was from a waste management association. A summary of 
the specific issues raised by commenters is provided below.
    The waste management association did not support excluding sludges 
derived from the biological treatment of listed hazardous wastes. The 
commenter noted that the sludges typically contain concentrations of 
heavy metals that warrant further treatment and Subtitle C disposal. 
EPA's listing background document for F006 electroplating sludges, for 
example, provides data on the presence of lead, cadmium, chromium and 
other toxic metals in such wastewater treatment sludges.
    Two States did not support the exclusion, noting that these sludges 
can continue to pose a threat to human health and the environment and 
should continue to be subject to the derived-from rule. The States also 
believed that these wastes should meet land disposal restriction (LDR) 
treatment standards, just as any other listed hazardous waste

[[Page 27290]]

is required to meet a treatment standard before being disposed in a 
permitted Subtitle C facility. One State noted that EPA proposed the 
retention of the mixture and derived-from rules in part because of the 
potential toxicity of wastewater treatment sludges. (See 64 FR 63389, 
November 19, 1999).
    One State commenter noted that there may be merit in excluding 
aggressive biological treatment residues. However, to make a definitive 
decision, the State would need to evaluate constituent concentration 
data, current management practices, environmental injury cases caused 
by the residues, and whether the residues commonly exhibit a hazardous 
waste characteristic. Since wastewater treatment is a bonafide 
treatment method proven to detoxify or otherwise treat hazardous waste 
and the residues are physically and/or chemically different from the 
hazardous wastes they were generated from, the State believed it was 
appropriate to view the residues as newly generated wastes and impose 
RCRA regulation only if the waste exhibited a hazardous waste 
characteristic.
    The rest of the commenters supported excluding sludges derived from 
the biological treatment of listed hazardous wastes. Many commenters 
noted that industrial biosludges currently are overmanaged as hazardous 
wastes at a high cost to industry. Several commenters added that 
residues from biological treatment processes have reduced organic 
constituent concentrations significantly relative to the original 
waste. Commenters noted that most listed wastewaters are 99% water and 
are therefore substantially different in terms of potential for 
environmental harm than a non-wastewater form of the same waste. Also, 
residues derived from aggressive biological treatment are fundamentally 
different (both chemically and physically) from the originally listed 
wastes and these residues should be considered a new point of 
generation. One commenter submitted data on the concentration of 
chemicals in a combined treatment sludge.
    Additionally, commenters claimed that in recent hazardous waste 
listings, EPA has recognized that treatment sludges do not necessarily 
present any significant environmental hazard even when there is 
sufficient hazard in the waste as generated to warrant listing by EPA 
(e.g., wastewater treatment sludges from carbamates, anthraquinone, and 
chlorinated aliphatics). Commenters also noted that public reporting of 
these very large volumes of derived-from waste misleads the public over 
the amount of actual hazardous waste in their communities.
    Several commenters believed that there should not be a specific 
contingent management requirement associated with the excluded 
biosludge. Rather, the sludge would be subject to state industrial non-
hazardous waste RCRA (Subtitle D) programs, including restrictions on 
industrial non-hazardous waste landfilling, combustion and other 
management options. Since industrial biosludge resulting from an 
aggressive biological treatment system is not significantly different 
from sewage sludge, the commenters expected that any restrictions 
placed on the use of sewage sludge would likewise apply to excluded 
sludge.
    A few commenters pointed out that the LDR program for 
characteristic wastes has over the years established new points of 
generation. The commenters noted that in the LDR program, EPA 
recognized that various treatment residuals differ from the wastes from 
which they are derived and should not continue to be regulated as the 
same wastes. In at least three other situations, EPA has made a 
specific determination that the generation of wastewater treatment 
biosludge constitutes a new point of generation, generally on the basis 
that the wastewater being treated falls into one treatability group and 
the resultant sludge into another. They are: (1) Sludge from the 
treatment of U154 contaminated groundwater--The sludge is considered 
newly generated waste because it is a different treatability group than 
the wastewater being treated--sludge generated from treating non-
ignitable wastewaters not derived from hazardous waste (03/21/96 
Berlow, EPA to Day, Bryan Cave, LLP); (2) LDR notification requirements 
for wastewaters and sludges--LDR requirements apply only to wastes that 
are hazardous at the point of generation. Non-hazardous sludges removed 
from a wastewater treatment unit require no LDR notification. The 
requirement to identify and treat for underlying hazardous constituents 
(UHCs) is not applicable to wastewaters managed in centralized 
wastewater treatment systems subject to the CWA or to sludges that are 
not hazardous at the point of generation (05/01/97 Cotsworth, EPA to 
Dolce, Award Environmental Inc.); and (3) applicability of land 
disposal restrictions to tank-based wastewater treatment systems--LDRs 
do not apply to waste managed in systems that are entirely tank-based; 
sludge generated from wastewater treatment belongs to a different 
treatability group, and is therefore a newly generated waste that 
should be evaluated at the point of generation (03/29/97 Berlow, EPA to 
Day, Bryan Cave, LLP).
(2) EPA Response to Comments on Excluding Residues From Aggressive 
Biological Treatment of Hazardous Waste
    EPA is considering a tailored exclusion for biological treatment 
residues, but does not believe that a blanket exclusion from the 
mixture and derived-from rules is appropriate for such wastes. Not all 
wastestreams are amenable to biological treatment, and the composition 
of the residuals generated from biological treatment would vary greatly 
depending on the influent and on the efficacy of the treatment system.
    We have, in the past, determined that biological treatment systems 
are inappropriate for metals and could result in impermissible dilution 
under the LDR program.\20\ We have also denied a delisting petition for 
K035 sludges resulting from aerated biological treatment of creosote in 
a surface impoundment in part because of downgradient groundwater 
contamination.\21\ In addition, we have information that facilities 
have attempted to avoid generating F037 and F038 wastes by adding 
minimal aeration to primary treatment units and claiming the sludges 
from these units as excluded.\22\
---------------------------------------------------------------------------

    \20\ EPA 1990. LDR Determination of Waste Stream Dilution, 
Letter from Jeffery Denit, Deputy Director, Office of Solid Waste to 
Bruce Smith, Director, Office of Hazardous Waste Programs, EPA 
Region III, October 14, 1990. [FAXBACK 13414, PPC 9551.1990(06)]
    \21\ EPA 1987. K035 Listing and Inclusion of Sludges from 
Biological Treatment of Creosote Production Wastes, Letter from 
Bruce R. Weddle, U.S. EPA, to Jordan Dern, Koppers Company, Inc., 
December 11, 1987. [FAXBACK 13105, PPC 9444.1987(52)].
    \22\ U.S. EPA 1991. Draft Region VIII Policy on ``Aggressive 
Biological Treatment'', Letter from Robert L. Duprey, Director, 
Hazardous Waste Management Division (EPA Region VIII) to Sylvia K. 
Lowrance, Director, Office of Solid Waste, April 19, 1991 (Ref: 
8HWM-RI)
---------------------------------------------------------------------------

    However, EPA believes there may be merit to the idea of regulating 
certain types of biological treatment residues differently. As noted in 
the comments, we have in the past excluded certain types of biological 
treatment wastes from regulation (see, for example, 40 CFR 
261.3(c)(2)(ii)(D)). There may be other types of waste similarly 
amenable to biological treatment. Before developing such a regulatory 
proposal, EPA would first gather and analyze data on biological 
treatment waste. Therefore, any such data would be welcomed by the 
Agency.

[[Page 27291]]

D. Excluding Hazardous Waste Combustion Residues

    Another of CMA's suggested options involves excluding residues from 
the combustion of listed hazardous waste. CMA argues that these wastes 
are both physically and chemically dissimilar from the wastes that were 
originally listed. In addition, CMA notes that combustion can virtually 
eliminate organic chemicals. Under the options presented in CMA's 
discussion papers, these wastes, which would include combustion ash, 
slag, air pollution control residue and scrubber water, would not be 
hazardous, even though they are generated from the treatment, storage 
or disposal of hazardous waste, unless they exhibit one or more of the 
hazardous waste characteristics of 40 CFR part 261, Subpart C.
(1) Comments on Excluding Hazardous Waste Combustion Residues
    EPA received comments from 15 commenters in response to the CMA 
recommendation to exclude hazardous waste combustion residues. Of those 
comments, seven were received from industries, two were from industry 
associations, four were from State Agencies, one was from a waste 
management company, and one was from a waste management association. A 
summary of the specific issues raised by commenters is provided below.
    One waste management association and two State commenters did not 
support excluding combustion residues, noting that there is a great 
deal of variability in combustion residues. While some organic 
compounds are destroyed effectively by the combustion process, the 
residue may contain persistent constituents (e.g., dioxins and metals) 
that are toxic. Accordingly, while the combustion byproducts may be 
physically and chemically dissimilar from the listed waste it is 
derived from, the byproducts have toxic properties that could cause 
environmental degradation. The commenters believed that relying on the 
TC by itself fails to provide adequate protection of human health and 
the environment. The commenters mentioned that not all metals of 
concern are covered by the TC. They also noted that the TC only 
measures potential risks via the groundwater pathway, and it is not 
definitive that groundwater is the driving risk pathway for these 
wastes. Because the TC approach does not comprehensively evaluate 
potential risks, wastes that do not exhibit hazardous waste 
characteristics are not necessarily non-hazardous. In addition, one 
State commenter believed it was prudent to wait for EPA's anticipated 
action on proposed combustion residues to address the physical and 
chemical properties of these wastes before any action is taken on CMA's 
proposal.
    Two State commenters stated that there may be merit in excluding 
residues from the combustion of listed hazardous wastes. However, to 
make a definitive decision, one State would need to evaluate 
constituent concentration data, current management practices, 
environmental injury cases caused by the residues, and whether the 
residues commonly exhibit a hazardous waste characteristic. Since 
bonafide treatment has occurred and the residues are physically and/or 
chemically different from the hazardous wastes they were generated 
from, the State believed it was appropriate to view the residues as 
newly generated wastes and impose RCRA regulation if the waste 
exhibited a hazardous waste characteristic. Another State commenter 
believed an exclusion for combustion residues could be appropriate if 
the combustion takes place in a permitted (not interim status) 
hazardous waste combustion device; any listed wastes are listed for 
organic hazardous constituents only; the residual must not exhibit any 
characteristics; and the residues meet LDRs, including standards for 
underlying constituents. This approach would protect human health and 
the environment fully and would allow many combustion residues to exit 
Subtitle C regulation once LDRs are met.
    The rest of the commenters believed that EPA should consider 
residues from hazardous waste combustion to be a new point of 
generation. These combustion residuals substantially differ in their 
physical and chemical makeup from the original listed hazardous wastes 
from which they are derived. Subtitle C regulation is not needed for 
such combustion residuals, especially if the residues do not exhibit 
hazardous characteristics. Instead, the residues can be managed 
adequately and protectively as industrial non-hazardous waste or 
discharged under the Clean Water Act. The commenters believed that the 
high cost of regulating these materials as hazardous waste purchases 
little or no increased protection of human health and the environment. 
The hazardous waste combustion process destroys virtually all of the 
organics in the listed wastes from which these residuals are derived, 
and the Toxicity Characteristic limits for metals are virtually the 
same as the health-based limits EPA-established for excluding Bevill 
wastes from Subtitle C regulation. One commenter submitted information 
on the operating parameters and limits for their combustion unit and 
the concentrations of the sludge from incinerator scrubber water 
generated.
    One industry commenter noted that in combustion-related 
rulemakings, EPA consistently has maintained that well-operated and 
maintained combustion units can achieve high combustion efficiencies 
and can be operated in a manner that is protective of human health and 
the environment. Therefore, the commenter recommended the exclusion be 
limited to residues from units that continuously monitor stack 
emissions of CO, and do not exceed a CO level of 100 ppmv measured as 
an hourly rolling average.
    While agreeing with CMA's proposal, one association commenter 
believed it should be extended to combustion residues from facilities 
operating pursuant to 40 CFR part 266, subpart F, specifically residues 
from precious metal reclamation operations. The commenter noted that 
the recovery of precious metals from hazardous waste is not a TSDF 
operation, and the units are not permitted under the same CFR sections. 
The commenter added that precious metal-bearing residues also are 
environmentally safe for two additional reasons: (1) Precious metal-
bearing residues must not exhibit one or more of the characteristics of 
hazardous waste and (2) the residues must contain economically 
significant amounts of precious metals (to partake of the authority of 
40 CFR 266.100(f)), and thus such wastes will be further reclaimed 
rather than disposed, ensuring environmentally protective management.
    One commenter supported the use of the TCLP extract concentration 
limits in Appendix VII to 40 CFR part 266 as the criteria for excluding 
combustion residues. Several commenters also believed that solid 
residues from hazardous waste combustion units that do not exhibit any 
toxicity characteristic should be considered industrial non-hazardous 
waste. As such, the materials would be subject to state industrial non-
hazardous waste programs.
(2) EPA Response to Comments on Excluding Hazardous Waste Combustion 
Residues
    EPA is considering a possible exclusion for certain combustion 
residues, but does not believe that a blanket exclusion from the 
mixture and derived-from rules is appropriate for such wastes. Although 
hazardous waste combustors must meet at least 99.99% DRE (destruction 
and removal efficiency), metals and certain organics may only be 
transferred to a residue.

[[Page 27292]]

The constituents can become significantly concentrated in the residue. 
EPA does not believe that stack emissions are a reliable measure of the 
risk posed by the combustion residue; in fact, as technology improves 
the removal capability of air pollution control devices, the resulting 
residue will likely have greater concentrations of hazardous 
constituents and may pose unacceptable risks if mismanaged. In 
addition, several of the mixture and derived-from waste damage cases 
that EPA has identified are a result of improper disposal of combustion 
residues.\23\
---------------------------------------------------------------------------

    \23\ See table 1, EPA 2000. Releases of Hazardous Constituents 
Associated with Mixture and Derived-from Wastes (An Update) U.S. 
EPA, April 2000.
---------------------------------------------------------------------------

    In addition, EPA is particularly concerned about the possible 
formation of dioxins and furans during hazardous waste combustion. In 
the September 1999 combustion rule, we noted that there is ``a 
considerable body of evidence'' to show that dioxin and furan compounds 
can be formed in the post-combustion regions of hazardous waste 
combustors (see 64 FR 52994). Because of this concern, we have added 
these dioxin and furan compounds to Appendix VIII of 40 CFR part 266, 
which lists products of incomplete combustion (PICs) likely to be found 
in stack effluents.
    However, EPA is considering a proposed tailored exclusion for 
certain combustion residues. For example, EPA is currently developing 
for public comment a proposed exclusion that focuses on wastes that 
have been slagged to liquefaction. These slagged wastes are unique 
because the high temperatures associated with liquefaction (2100 deg.F, 
typically) appear to eliminate organic chemicals, including PICs, and 
generate a slagged residue which is a glassy, liquid, molten material 
that, when cooled, forms a potentially durable, homogeneous, solid 
mass. This combination of elimination of organic chemicals and change 
in physical form (which can reduce risk from non-groundwater pathways) 
make these slagged residues potential candidates for de-regulation. 
However, the liquefaction process does not reduce the concentration of 
toxic metals in the waste, which we would need to evaluate for 
potential risks to human health and the environment. EPA is planning to 
address this issue, as well as other possible tailored exclusions for 
combustion residues, in the upcoming proposal.

E. Expanding the Current De Minimis Exclusion

    A final regulatory option to revise the mixture and derived-from 
rules would expand a current exclusion for ``de minimis'' losses that 
result from the manufacture of commercial chemical products. The 
current exclusion, found in 40 CFR 261.3(a)(2)(iv)(D), excludes small 
losses of a commercial chemical product that can result from normal 
handling of the chemicals during the manufacturing process. The 
existing exclusion applies to commercial chemical products or 
intermediates, when they are lost during the manufacturing operation 
and are subsequently managed as a wastewater subject to regulation 
under the Clean Water Act (CWA) (see 46 FR 56586). The suggested 
expansion of this option would also exclude small losses from the 
normal handling of all listed hazardous wastes (instead of just 
commercial chemical products) when managed as a wastewater under the 
CWA. One rationale for the current ``de minimis'' exclusion is that a 
facility has little economic incentive to allow spills, leaks or other 
losses of commercial products. With respect to wastes, CMA believes 
that tank, container and air emission management standards of 40 CFR 
parts 264 and 265, subparts I, J, BB, and CC serve to encourage safe 
management of these wastes.
(1) Summary of Comments on Expanding the Current De Minimis Exclusion
    EPA received comments from 15 commenters in response to the 
suggested expansion of the de minimis exclusion. Of those comments, six 
were received from industries, four were from industry associations, 
three were from State Agencies, one was from a Federal Government 
Agency, and one was from a waste management association. A summary of 
the specific issues raised by commenters is provided below.
    Three commenters did not support the exclusion, believing that the 
exclusion might serve as an incentive for generators to spill or leak 
listed wastes into non-hazardous wastewater systems if those wastes 
were eligible for an exclusion. The current exclusion exists for 
commercial chemical products and companies typically ensure that raw 
materials/products are handled in a manner which would minimize losses, 
as these materials/products are valuable. The commenters did not 
believe that companies necessarily would take the same amount of care 
to prevent losses of listed wastes, if those wastes were excluded from 
Subtitle C.
    One State commenter supported the exclusion. However, the State 
believes that rinsate from large hazardous waste containers that are 
rendered empty should be outside the definition of a de minimis loss. 
Large containers such as tanker trucks could contain substantial 
quantities (possibly hundreds of gallons) of hazardous waste. Such a 
volume of hazardous waste is outside the scope of losses that should be 
defined as de minimis and should not be defined as such.
    One industry commenter stated that it was not clear from the 
preamble discussion what was meant by ``rinsate from empty containers 
or from containers that are rendered empty by that rinsing.'' The 
commenter noted that rinsate from containers that held hazardous waste 
``generally contains concentrations of hazardous constituents which are 
at least as high as the original waste'' and may contain significant 
quantities of solids. The quantities used to rinse containers of this 
type also may be significant depending upon the level of contamination 
in the container. In some cases it is not possible to clean a container 
to the point of being empty under the RCRA regulations and the 
container has to be disposed of as hazardous waste. The commenter 
believed that this issue must be clarified further before any exclusion 
could be considered. An industry association commenter also noted that 
the CMA proposal did not identify adequately the wastes for which the 
exclusion would operate. Since RCRA-empty container rinsate is already 
excluded, the commenter believed it should be specified that any 
exclusion need only address acute hazardous waste rinsate.
    The rest of the commenters supported expanding the de minimis 
exclusion to all listed wastes. Several commenters believed that the 
exclusion could be extended beneficially to cover the very small losses 
from the normal handling of all listed wastes. The stringent regulation 
of hazardous waste handling at the site of generation means that few 
losses of this type would be expected to occur. The ability to manage 
de minimis losses of listed wastes as non-hazardous would ease RCRA 
compliance significantly without compromising the integrity of the 
NPDES wastewater treatment system or protection of human health and the 
environment.
    The commenters noted that there was no reason to assume that a non-
hazardous industrial wastewater treatment facility was any less capable 
of providing adequate treatment of the hazardous constituents found in 
listed wastes. EPA's stringent container and

[[Page 27293]]

tank management standards in 40 CFR parts 264 and 265 subparts I and J, 
and air emission standards in subpart CC, serve as powerful incentives 
to properly manage these wastes to minimize the occurrence of ``de 
minimis'' losses. The Federal commenter supported the expansion, noting 
that it would provide to military installations the same level of 
regulation as is currently applicable to manufacturing industries. One 
industry commenter recommended that facilities wishing to take 
advantage of this exclusion be required to develop and implement 
written Best Management Practices (BMP) for all loading, unloading and 
transfer operations which are designed to minimize spills and prevent 
abuse of the exclusion.
    One commenter questioned why EPA never has set out a scientific 
rationale by which it reserves the discriminatory use of the de minimis 
rule to those engaged in the manufacturing process and denies it to all 
others, including stand-alone bulk liquid commercial chemical storage 
terminals. The commenter also suggested that de minimis losses include 
those from normal material handling operations (e.g., spills from the 
unloading or transfer of materials from bins or other containers, leaks 
from pipes, valves or other devices used to transfer materials); minor 
leaks of process equipment, storage tanks or containers, leaks from 
well-maintained pump packings and seals; sample purgings; relief device 
discharges; discharges from safety showers and rinsing and cleaning of 
personal safety equipment; and rinsate from empty containers or from 
containers that are rendered empty by that rinsing.
    Another commenter believed that there would be significant benefits 
from allowing de minimis losses of commercial chemical products from 
laboratories to be covered by the current regulatory exclusion. The 
types of commercial chemical products being used and tested in the 
laboratory also could be expected to be amenable to effective treatment 
in an on-site wastewater treatment system. The commenter noted that 
significant time, effort and cost is involved in segregating and 
capturing these types of de minimis losses from on-site laboratories.
(2) EPA's Response to Comments on Expanding the Current De Minimis 
Exclusion
    EPA is considering the possibility of expanding the current de 
minimis exclusion for wastes managed in a wastewater treatment system 
subject to the Clean Water Act. However, EPA is concerned about the 
possible negative incentives that might result from extending the de 
minimis exclusion to wastes listed in 40 CFR 261.31 and 261.32 (F and K 
wastes, respectively). As noted in the comments, there is a direct 
economic incentive to ensuring that raw materials/products are handled 
in a manner which would minimize losses, as these materials/products 
are valuable. This incentive does not exist for hazardous waste. The 
concept of ``de minimis'' is also variable, depending on the quantities 
of material handled and the relationship of those quantities with the 
flowrate of the facility's wastewater treatment plant. However, EPA 
realizes that separation of small leaks of certain hazardous wastes can 
sometimes be impractical.
    One possible approach would be to base the concept of ``de 
minimis'' on some fixed quantity of the waste, such as a Reportable 
Quantity (RQ) in Superfund regulations (see 40 CFR 302.4 and Table 
302.4). By statute, all hazardous wastes must be given an RQ. EPA may 
pursue the concept of de minimis related to RQs (or some fraction or 
multiple thereof) as we consider this issue further. In pursuing such a 
change, EPA would do so through a proposed rulemaking.
    In conclusion, EPA is currently developing proposals related to two 
of the suggestions that we believe to be the most straightforward to 
address: expanding the current headworks exclusion and excluding 
certain combustion residues (see Sections X.A. and X.D. respectively). 
We will also consider developing additional proposals on the other 
suggestions as well as other targeted exemptions, but we believe more 
analysis would first be necessary to decide how to address specific 
issues raised in the public. EPA welcomes any information or data that 
would help us in developing these analyses.

State Authorization

XI. How Will Today's Regulatory Changes Be Administered and 
Enforced in the States?

    Under section 3006 of RCRA, EPA may authorize qualified States to 
carry out the RCRA hazardous waste program within the State. Following 
authorization, we maintain independent enforcement authority under 
sections 3007, 3008, 3013, and 7003 of RCRA, although authorized States 
have enforcement responsibility. An authorized State could become 
authorized for today's regulatory changes by following the approval 
process described under 40 CFR 271.21. See 40 CFR part 271 for the 
overall standards and requirements for authorization.
    We are finalizing the retention of the mixture and derived-from 
rules. Most states have already received authorization for the mixture 
and derived-from rules as they currently stand. The rules are already 
in effect in those authorized States. Those states that are already 
authorized for the mixture and derived-from rules do not need to obtain 
authorization for those rules again. We are also revising those rules 
under the authority of sections 3001(a), 3002(a), and 3004(a) of RCRA. 
These revisions will not go into effect in authorized States until they 
adopt the revisions and receive authorization from us for the revision 
to their regulations.
    None of today's revisions are more stringent or broaden the scope 
of the existing Federal requirements. Authorized States are not 
required to modify their programs when we promulgate changes to Federal 
requirements that are less stringent than, or that narrow the scope of, 
existing Federal requirements. This flexibility stems from RCRA section 
3009, which allows the States to impose (or retain) standards that are 
more stringent than those in the Federal program. (See also 40 CFR 
271.1(i)). Therefore, States are not required to adopt the revisions to 
the mixture and derived-from rules in today's rule, although EPA will 
strongly encourage their adoption.

Administrative Requirements

XII. How Has EPA Fulfilled the Administrative Requirements for This 
Rulemaking?

    Several statutes and executive orders apply to rulemaking. Below is 
an explanation of how we address the requirements in those provisions:

A. Executive Order 12866: Determination of Significance

    Under Executive Order 12866 (58 FR 51,735 (Oct. 4, 1993)), EPA must 
determine whether a regulatory action is ``significant'' and, 
therefore, subject to OMB review and the other provisions of the 
Executive Order. The Order defines a ``significant regulatory action'' 
as one that is likely to result in a rule that may:
    (1) Have an annual effect on the economy of $100 million or more or 
adversely affect in a material way the economy, a sector of the 
economy, productivity, competition, jobs, the environment, public 
health or safety, or State, local, or tribal governments or 
communities;

[[Page 27294]]

    (2) Create a serious inconsistency or otherwise interfere with an 
action taken or planned by another agency;
    (3) Materially alter the budgetary impact of entitlements, grants, 
user fees, or loan programs or rights and obligations or recipients 
thereof; or
    (4) Raise novel legal or policy issues arising out of legal 
mandates, the President's priorities, or the principles set forth in 
Executive Order 12866.
    Pursuant to the fourth term of Executive Order 12866, we have 
determined that this rule is a ``significant regulatory action'' 
because there are novel policy issues arising out of legal mandates. As 
such, this action was submitted to OMB for review. Changes made in 
response to OMB suggestions or recommendations are documented in the 
docket to today's rule.
    Although today's final rule is not ``economically significant,'' 
the Agency prepared an economics background document in support of 
today's rule, titled Economic Assessment of the U.S. EPA's 2001 Final 
Rule Revising the Mixture and Derived-From Rules.
    There are currently 29 hazardous waste codes within the RCRA 
program listed solely for ignitability (I), corrosivity (C), and/or 
reactivity (R) characteristics. Today's rule excludes these wastes from 
RCRA Subtitle C regulation, if such wastes are de-characterized and 
meet the associated LDR treatment standards.To estimate the potential 
economic impact of excluding these 29 characteristically-listed RCRA 
waste codes, we analyzed the type and quantity of industrial hazardous 
wastes contained in the two databases: the 1986 ``Generator Survey'', 
and the 1996 ``National Hazardous Waste Constituent Survey.'' These two 
databases are described in the Economic Assessment background document.
    This exclusion is expected to benefit the relevant segment of the 
RCRA regulated community by reducing the cost of shipping and disposing 
these de-characterized wastes. This potential cost savings is modeled 
in this study as consisting of two components:
    (1) The difference between the cost for disposal of treatment 
residuals from these 29 waste codes in hazardous landfills (i.e., 
current or ``baseline'' practice), compared to the cost for disposal in 
nonhazardous landfills under this exclusion.
    (2) The reduction in burden hours and associated burden cost for no 
longer requiring preparation, transmitting and filing of truck shipment 
hazardous waste manifests (EPA Form 8700-22) for these potentially 
excluded wastes.
    The database extractions, computations and findings of the impact 
analysis are presented in the Economic Assessment background document. 
The highlights of EPA's estimated economic impacts for this revision 
are as follows:

--236 applicable industrial hazardous waste streams, totaling 3.6 
million tons in annual generation (before RCRA Subtitle C hazardous 
waste treatment) by an estimated 120 US facilities.
--As generated, these waste streams consist of 99% liquid (mainly 
organic liquids) and 1% non-liquid (sludge) waste forms.
--The 3.6 million annual tons of applicable waste (before RCRA Subtitle 
C hazardous waste treatment), represents 1.4% of the total RCRA 
hazardous waste universe (1993 BRS large generator total quantity = 258 
million tons).
--Approximately 75% of the potentially excluded waste streams are 
identified by waste code F003 (spent non-halogenated solvents) plus a 
characteristic waste code (for example, D001), and 19% are identified 
by waste code F003 only.
--Applicable waste streams are located in 17 four-digit level SIC code 
industry sectors. 146 (62%) of the 236 applicable waste streams are 
generated by industries in SIC 28 (represented also by NAICS code 325).
--There are 51 different hazardous chemical constituents in the 
wastestreams before treatment; prevalent ones include: ethylbenzene, 
toluene, methyl ethyl ketone, methanol, ethyl acetate, xylenes, 
acetone, methylene chloride, and n-butyl alcohol.
--After RCRA Subtitle C treatment (mainly incineration), the 236 
wastestreams result in the annual disposal of about 57,400 tons of 
treatment residuals, primarily in the form of incineration ash.
--Potential annual industry waste treatment residual disposal cost 
savings is estimated at $4.593 million, while annual reduction in truck 
shipment manifesting cost is estimated at $0.455 million. These two 
cost savings components represent a total annual cost savings estimate 
of $5.048 million. Applying -15% to +30% cost estimation uncertainty to 
this point-estimate (as explained in the background document), produces 
the associated cost savings estimation range of $4.29 to $6.56 million 
per year.

B. Regulatory Flexibility Act

    Pursuant to the 1980 Regulatory Flexibility Act (RFA) (5 U.S.C. 601 
et seq., as amended by the Small Business Regulatory Enforcement 
Fairness Act (SBREFA) of 1996), whenever an agency publishes a notice 
of rulemaking for any proposed or final rule, it must prepare and make 
available for public comment, a regulatory flexibility analysis that 
describes the effect of the rule on small entities (i.e., small 
businesses, small organizations, and small governmental jurisdictions). 
However, a regulatory flexibility analysis is not required if the head 
of an agency certifies that the rule will not have a ``significant'' 
economic impact on a substantial number of small entities.
    SBREFA amended the Regulatory Flexibility Act to require Federal 
agencies to provide a statement of the factual basis for certifying 
that a rule will not have a ``significant'' economic impact on a 
substantial number of small entities. Regulatory Flexibility Act (RFA), 
as amended by the Small Business Regulatory Enforcement Fairness Act of 
1996 (SBREFA), 5 U.S.C. 601 et. seq.
    The RFA generally requires an agency to prepare a regulatory 
flexibility analysis of any rule subject to notice and comment 
rulemaking requirements under the Administrative Procedure Act or any 
other statute unless the agency certifies that the rule will not have a 
significant economic impact on a substantial number of small entities. 
Small entities include small businesses, small organizations, and small 
governmental jurisdictions.
    For purposes of assessing the impacts of today's rule on small 
entities, small entity is defined as: (1) A small business that meets 
the Small Business Administration size standards established for 
industries as described in the North American Industry Classification 
System (see http://www.sba.gov/size/NAICS-cover-page.html).; (2) a 
small governmental jurisdiction that is a government of a city, county, 
town, school district or special district with a population of less 
than 50,000; and (3) a small organization that is any not-for-profit 
enterprise which is independently owned and operated and is not 
dominant in its field.
    After considering the economic impacts of today's final rule on 
small entities, I certify that this action will not have a significant 
economic impact on a substantial number of small entities. In 
determining whether a rule has a significant economic impact on a 
substantial number of small entities, the impact of concern is any 
significant adverse economic impact on small entities, since the 
primary purpose of the regulatory flexibility analyses is to

[[Page 27295]]

identify and address regulatory alternatives ``which minimize any 
significant economic impact of the proposed rule on small entities.'' 5 
U.S.C. 603 and 604. Thus, an agency may certify that a rule will not 
have a significant economic impact on a substantial number of small 
entities if the rule relieves regulatory burden, or otherwise has a 
positive economic effect on all of the small entities subject to the 
rule.
    The following discussion presents the facts for EPA's 
determination. EPA has examined this rule's potential effects on small 
entities as required by the RFA/SBREFA, and has determined that this 
action will not have a significant economic impact on a substantial 
number of small entities. As discussed in Section XII.A of this 
preamble, we have prepared an economic analysis of the potential 
effects of this rule, and have determined that the rule is expected to 
have a net beneficial effect on eligible entities, in the form of 
reduced environmental regulatory compliance costs for industrial waste 
management. The final rule allows small (and other size) entities 
voluntarily to exempt certain solid wastes (i.e. mixtures and 
derivatives of solid wastes listed as RCRA hazardous solely for the 
ignitability, corrosivity, and/or reactivity characteristics, which no 
longer exhibit any such characteristic, and which comply with RCRA land 
disposal restrictions), from compliance with the RCRA Subtitle C 
hazardous waste regulatory system. The economic analysis evaluates the 
extent to which both small quantity and large quantity industrial waste 
generators might be potentially eligible for cost savings under this 
rule, as a result of seeking this exemption. This proposed rule is 
voluntary, and the overall economic effect of this regulation for both 
small and large entities which are eligible to participate, is expected 
to be a net average annual reduction in industry regulatory burden and 
compliance costs. Consequently, because the net economic impacts and 
effects of this rule are beneficial rather than adverse, we have 
concluded that today's final rule will relieve regulatory burden for 
all small entities.

C. Paperwork Reduction Act (Information Collection Request)

    The information collection requirements in this rule have been 
submitted for approval to the Office of Management and Budget (OMB) 
under the Paperwork Reduction Act, 44 U.S.C. 3501 et seq. An 
Information Collection Request (ICR) document has been prepared by EPA 
(ICR No. 0801.12) and a copy may be obtained from Sandy Farmer by mail 
at OP Regulatory Information Division; U.S. Environmental Protection 
Agency (2137); 1200 Pennsylvania Avenue NW.; Washington, DC 20460, by 
E-mail at [email protected], or by calling (202) 260-2740. A 
copy may also be downloaded off the Internet at http://www.epa.gov/icr.
    Today's revisions of 40 CFR 261.3 do not include any new 
recordkeeping or reporting requirements. However, the revisions could 
reduce the burden estimate for existing RCRA information collection 
requirements, such as the Uniform Hazardous Waste Manifest (Form 8700-
22A). As discussed in Section XII.A. of this preamble, today's rule 
could exclude approximately 54,700 tons of treated waste residuals 
(mainly incineration ash) per year. Assuming that these now-excluded 
wastes are shipped offsite for disposal, and assuming that an average 
truckload carries about 20 tons (of solids), today's rule could result 
in approximately 2,870 shipments per year that would no longer require 
Uniform Hazardous Waste Manifest. (This estimate is an upper bound, 
since many hazardous waste generators manage their waste on-site). The 
RCRA Hazardous Waste Manifest System ICR (No. 0801.12.) estimates an 
annual burden of 1.29 hours per shipment of hazardous waste. Therefore, 
today's rule could reduce the total burden associated with manifests by 
3,702 hours per year. (The current burden associated with manifests is 
estimated to be 2,920,383 hours per year).
    Burden means the total time, effort, or financial resources 
expended by persons to generate, maintain, retain, disclose, or provide 
information to or for a Federal agency. This includes the time needed 
to review instructions; develop, acquire, install, and utilize 
technology and systems for the purposes of collecting, validating, and 
verifying information, processing and maintaining information, and 
disclosing and providing information; adjust the existing ways to 
comply with any previously applicable instructions and requirements; 
train personnel to be able to respond to a collection of information; 
search data sources; complete and review the collection of information; 
and transmit or otherwise disclose the information.
    An Agency may not conduct or sponsor, and a person is not required 
to respond to a collection of information unless it displays a 
currently valid OMB control number. The OMB control numbers for EPA's 
regulations are listed in 40 CFR part 9 and 48 CFR chapter 15.

D. Unfunded Mandates Reform Act

    Title II of the Unfunded Mandates Reform Act of 1995 (UMRA), Public 
Law 104-4, establishes requirements for Federal agencies to assess the 
effects of their regulatory actions on State, local, and tribal 
governments and the private sector. Under section 202 of the UMRA, we 
generally must prepare a written statement, including a cost-benefit 
analysis, for proposed and final rules with ``Federal mandates'' that 
may result in expenditures to State, local, and tribal governments, in 
the aggregate, or to the private sector, of $100 million or more in any 
one year.
    Before promulgating an EPA rule for which a written statement is 
needed, section 205 of the UMRA generally requires EPA to identify and 
consider a reasonable number of regulatory alternatives and adopt the 
least costly, most cost-effective or least burdensome alternative that 
achieves the objectives of the rule. The provisions of section 205 do 
not apply when they are inconsistent with applicable law. Moreover, 
section 205 allows EPA to adopt an alternative other than the least 
costly, most cost-effective or least burdensome alternative if the 
Administrator publishes, with the final rule, an explanation why that 
alternative was not adopted. Before EPA establishes any regulatory 
requirements that may significantly or uniquely affect small 
governments, including tribal governments, we must have developed a 
small government agency plan under section 203 of the UMRA. The plan 
must provide for notifying potentially affected small governments, 
enabling officials of affected small governments to have meaningful and 
timely input in the development of EPA regulatory proposals with 
significant Federal intergovernmental mandates, and informing, 
educating, and advising small governments on compliance with the 
regulatory requirements.
    Today's revision to the mixture and derived-from rules is 
voluntary, and because these revisions are less stringent than the 
current regulations, State governments are not required to adopt the 
regulatory changes. The UMRA generally excludes from the definition of 
``Federal intergovernmental mandate'' duties that arise from 
participation in a voluntary federal program. The UMRA also excludes 
from the definition of ``Federal private sector mandate'' duties that 
arise from participation in a voluntary federal program. Therefore we 
have determined that today's rule is not subject to the requirements of 
sections 202 and 205 of UMRA.

[[Page 27296]]

E. Executive Order 13132 (Federalism)

    Executive Order 13132, entitled ``Federalism'' (64 FR 43255, August 
10, 1999), requires EPA to develop an accountable process to ensure 
``meaningful and timely input by State and local officials in the 
development of regulatory policies that have federalism implications.'' 
``Policies that have federalism implications'' is defined in the 
Executive Order to include regulations that have ``substantial direct 
effects on the States, on the relationship between the national 
government and the States, or on the distribution of power and 
responsibilities among the various levels of government.''
    This final rule does not have federalism implications. It will not 
have substantial direct effects on the States, on the relationship 
between the national government and the States, or on the distribution 
of power and responsibilities among the various levels of government, 
as specified in Executive Order 13132. As explained in Section XI of 
this preamble, none of today's revisions are more stringent or broaden 
the scope of the existing Federal requirements. Therefore, States are 
not required to adopt the revisions to the mixture and derived-from 
rules in today's rules. Thus, Executive Order 13132 does not apply to 
this rule. Although section 6 of Executive Order 13132 does not apply 
to this rule, EPA did consult with representatives of state governments 
in developing this rule, and included representatives of state 
governments as participants in the rulemaking workgroup. For an 
overview of EPA's consultations with the States, please see Summary of 
Consultations with State Representatives for the Hazardous Waste 
Identification Rule (HWIR).

F. Executive Order 13175: Consultation and Coordination With Indian 
Tribal Governments

    Executive Order 13175, entitled ``Consultation and Coordination 
with Indian Tribal Governments'' (65 FR 67249, November 6, 2000), 
requires EPA to develop an accountable process to ensure ``meaningful 
and timely input by tribal officials in the development of regulatory 
policies that have tribal implications.'' ``Policies that have tribal 
implications'' is defined in the Executive Order to include regulations 
that have ``substantial direct effects on one or more Indian tribes, on 
the relationship between the Federal government and the Indian tribes, 
or on the distribution of power and responsibilities between the 
Federal government and Indian tribes.''
    This final rule does not have tribal implications. It will not have 
substantial direct effects on tribal governments, on the relationship 
between the Federal government and Indian tribes, or on the 
distribution of power and responsibilities between the Federal 
government and Indian tribes, as specified in Executive Order 13175. 
Because today's revision to the mixture and derived-from rules is less 
stringent than the existing program, it would not create any mandate on 
Indian tribal governments. Thus, Executive Order 13175 does not apply 
to this rule.

G. Executive Order 13045: Protection of Children From Environmental 
Health Risks and Safety Risks

    ``Protection of Children from Environmental Health Risks and Safety 
Risks'' (62 FR 19885, April 23, 1997) applies to any rule that: (1) is 
determined to be ``economically significant'' as defined under 
Executive Order 12866, and (2) concerns an environmental health or 
safety risk that we have reason to believe may have a disproportionate 
effect on children. If the regulatory action meets both criteria, we 
must evaluate the environmental health or safety effects of the planned 
rule on children, and explain why the planned regulation is preferable 
to other potentially effective and reasonably feasible alternatives 
considered by us. This rule is not subject to Executive Order 13045 
because it is not an economically significant rule as defined by 
Executive Order 12866 and because the environmental health or safety 
risks addressed by this action do not present a disproportionate risk 
to children.

H. National Technology Transfer and Advancement Act of 1995

    Section 12(d) of the National Technology Transfer and Advancement 
Act of 1995 (``NTTAA''), Public Law 104-113, section 12(d) (15 U.S.C. 
272 note) directs us to use voluntary consensus standards in our 
regulatory activities unless to do so would be inconsistent with 
applicable law or otherwise impractical. Voluntary consensus standards 
are technical standards (for example, materials specifications, test 
methods, sampling procedures, and business practices) that are 
developed or adopted by voluntary consensus standards bodies. The NTTAA 
directs EPA to provide Congress, through OMB, explanations when we 
decide not to use available and applicable voluntary consensus 
standards. Today's rule does not involve technical standards. 
Therefore, EPA is not considering the use of any voluntary consensus 
standards.

I. Executive Order 12898: Environmental Justice

    Under Executive Order 12898, ``Federal Actions to Address 
Environmental Justice in Minority Populations and Low-Income 
Populations,'' as well as through EPA's April 1995, ``Environmental 
Justice Strategy, OSWER Environmental Justice Task Force Action Agenda 
Report,'' and National Environmental Justice Advisory Council, EPA has 
undertaken to incorporate environmental justice into its policies and 
programs. EPA is committed to addressing environmental justice 
concerns, and is assuming a leadership role in environmental justice 
initiatives to enhance environmental quality for all residents of the 
United States. The Agency's goals are to ensure that no segment of the 
population, regardless of race, color, national origin, or income, 
bears disproportionately high and adverse human health and 
environmental effects as a result of EPA's policies, programs, and 
activities. Today's rule is not expected to negatively impact any 
community, and therefore is not expected to cause any 
disproportionately high and adverse impacts to minority or low-income 
communities versus non-minority or affluent communities.

J. Congressional Review Act

    The Congressional Review Act, 5 U.S.C. 801 et seq., as added by the 
Small Business Regulatory Enforcement Fairness Act of 1996, generally 
provides that before a rule may take effect, the agency promulgating 
the rule must submit a rule report, which includes a copy of the rule, 
to each House of the Congress and to the Comptroller General of the 
United States. EPA will submit a report containing this rule and other 
required information to the U.S. Senate, the U.S. House of 
Representatives, and the Comptroller General of the United States prior 
to publication of the rule in the Federal Register. A major rule cannot 
take effect until 60 days after it is published in the Federal 
Register. This action is not a ``major rule'' as defined by 5 U.S.C. 
804(2). This rule will be effective August 14, 2001.

Technical Correction

XIII. What Technical Correction Is EPA Making in Today's 
Rulemaking?

    In today's final rule, we also are correcting an error made in a 
previous notice. In the final rule published June 8, 2000, 
``Organobromines Production Wastes; Petroleum Refining Wastes; 
Identification and Listing of Hazardous Waste; Land Disposal 
Restrictions; Final Rule and Correcting Amendments' (65

[[Page 27297]]

FR 36365), the entry for listed hazardous waste code U048 (o-
Chlorophenol) in Table 1 of Appendix VII to 40 CFR part 268 
(``Effective Dates of Surface Disposed Wastes (Non-Soil and Debris) 
Regulated in the LDRs-Comprehensive List'') was inadvertently removed. 
Today we are amending Table 1 of Appendix VII to 40 CFR part 268 to 
reinsert the entry for hazardous waste code U048. The LDR effective 
date for this waste code (all waste categories) was August 8, 1990.

List of Subjects

40 CFR Part 261

    Environmental protection, Hazardous waste, Recycling, Waste 
treatment and disposal.

40 CFR Part 268

    Hazardous waste, Reporting and recordkeeping requirements.

    Dated: April 30, 2001.
Christine Todd Whitman,
Administrator.

    For the reasons set out in the preamble, title 40, chapter I of the 
Code of Federal Regulations is amended as follows:

PART 261--IDENTIFICATION AND LISTING OF HAZARDOUS WASTE

    1. The authority citation for part 261 continues to read as 
follows:

    Authority: 42 U.S.C. 6905, 6912(a), 6921, 6922, 6924(y), and 
6938.

    2. Section 261.3 is amended by removing and reserving paragraph 
(a)(2)(iii) and revising paragraph (a)(2)(iv) and the first sentence of 
paragraph (c)(2)(i); and by adding paragraphs (g) and (h) to read as 
follows:


Sec. 261.3  Definition of hazardous waste.

    (a) * * *
    (2) * * *
    (iii) [Reserved]
    (iv) It is a mixture of solid waste and one or more hazardous 
wastes listed in subpart D of this part and has not been excluded from 
paragraph (a)(2) of this section under 40 CFR 260.20 and 260.22, 
paragraph (g) of this section, or paragraph (h) of this section; 
however, the following mixtures of solid wastes and hazardous wastes 
listed in subpart D of this part are not hazardous wastes (except by 
application of paragraph (a)(2)(i) or (ii) of this section) if the 
generator can demonstrate that the mixture consists of wastewater the 
discharge of which is subject to regulation under either section 402 or 
section 307(b) of the Clean Water Act (including wastewater at 
facilities which have eliminated the discharge of wastewater) and;
* * * * *
    (c) * * *
    (2) (i) Except as otherwise provided in paragraph (c)(2)(ii), (g) 
or (h) of this section, any solid waste generated from the treatment, 
storage, or disposal of a hazardous waste, including any sludge, spill 
residue, ash emission control dust, or leachate (but not including 
precipitation run-off) is a hazardous waste. * * *
* * * * *
    (g)(1) A hazardous waste that is listed in subpart D of this part 
solely because it exhibits one or more characteristics of ignitability 
as defined under Sec. 261.21, corrosivity as defined under Sec. 261.22, 
or reactivity as defined under Sec. 261.23 is not a hazardous waste, if 
the waste no longer exhibits any characteristic of hazardous waste 
identified in subpart C of this part.
    (2) The exclusion described in paragraph (g)(1) of this section 
also pertains to:
    (i) Any mixture of a solid waste and a hazardous waste listed in 
subpart D of this part solely because it exhibits the characteristics 
of ignitability, corrosivity, or reactivity as regulated under 
paragraph (a)(2)(iv) of this section; and
    (ii) Any solid waste generated from treating, storing, or disposing 
of a hazardous waste listed in subpart D of this part solely because it 
exhibits the characteristics of ignitability, corrosivity, or 
reactivity as regulated under paragraph (c)(2)(i) of this section.
    (3) Wastes excluded under this section are subject to part 268 of 
this chapter (as applicable), even if they no longer exhibit a 
characteristic at the point of land disposal.
    (h)(1) Hazardous waste containing radioactive waste is no longer a 
hazardous waste when it meets the eligibility criteria and conditions 
of 40 CFR part 266, Subpart N (``eligible radioactive mixed waste'').
    (2) The exemption described in paragraph (h)(1) of this section 
also pertains to:
    (i) Any mixture of a solid waste and an eligible radioactive mixed 
waste; and
    (ii) Any solid waste generated from treating, storing, or disposing 
of an eligible radioactive mixed waste.
    (3) Waste exempted under this section must meet the eligibility 
criteria and specified conditions in 40 CFR 266.225 and 40 CFR 266.230 
(for storage and treatment) and in 40 CFR 266.310 and 40 CFR 266.315 
(for transportation and disposal). Waste that fails to satisfy these 
eligibility criteria and conditions is regulated as hazardous waste.

PART 268--LAND DISPOSAL RESTRICTIONS

    3. The authority citation for part 268 continues to read as 
follows:

    Authority: 42 U.S.C. 6905, 6912(a), 6921, and 6924.

Appendix VII to Part 268--[Amended]

    4. Appendix VII to part 268 Table 1 is amended by adding the 
following wastestream in alphanumeric order (by the first column) to 
read as follows:

----------------------------------------------------------------------------------------------------------------
                Waste code                           Waste category                     Effective date
----------------------------------------------------------------------------------------------------------------
 
           *              *              *              *              *              *              *
U048.....................................  All..............................  Aug. 8, 1990.
----------------------------------------------------------------------------------------------------------------


[FR Doc. 01-11411 Filed 5-15-01; 8:45 am]
BILLING CODE 6560-50-P