[Federal Register Volume 69, Number 54 (Friday, March 19, 2004)]
[Proposed Rules]
[Pages 12995-13011]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 04-6216]


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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 261

[FRL-7638-1]


Hazardous Waste Management System; Proposed Exclusion for 
Identification and Listing of Hazardous Waste

AGENCY: Environmental Protection Agency (EPA).

ACTION: Proposed rule.

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SUMMARY: The EPA (also, ``the Agency'' or ``we'' in this preamble) is 
proposing to grant a petition submitted by General Electric Company 
(GE), King of Prussia, Pennsylvania, to exclude (or ``delist''), on a 
one-time basis, certain solid wastes that have been deposited and/or 
accumulated in two (2) on-site drying beds and two (2) on-site basins 
referred to by GE as ``surface impoundments'' at its RCA del Caribe 
facility in Barceloneta, Puerto Rico from the lists of hazardous wastes 
contained in the regulations. These drying beds and basins were used 
exclusively for disposal of its chemical etching wastewater treatment 
plant (WWTP) sludge from 1971 to 1978.
    The Agency has tentatively decided to grant the petition based on 
an evaluation of waste-specific information provided by GE. This 
proposed decision, if finalized, would conditionally exclude the 
petitioned waste from the requirements of hazardous waste regulations 
under the Resource Conservation and Recovery Act (RCRA).
    If finalized, the EPA would conclude that GE's petitioned waste is 
nonhazardous with respect to the original listing criteria or factors 
which could cause the waste to be hazardous. The waste would still be 
subject to Local, State (as used herein the term State includes the 
Commonwealth of Puerto Rico) and Federal regulations for nonhazardous 
solid waste.

DATES: The Agency will accept public comments on this proposed decision 
until May 3, 2004. Comments postmarked after the close of the comment 
period will be stamped ``late.'' These ``late'' comments may not be 
considered in formulating a final decision.
    Any person may request a hearing on this proposed rule by filing a 
written request by April 5, 2004. Pursuant to 40 CFR 260.20(d), the 
request must state the issue to be raised and explain why written 
comments would not suffice to communicate the person's views.

ADDRESSES: Please send two copies of your comments to Ernst J. Jabouin, 
RCRA Program Branch (2DEPP-RPB), Environmental Protection Agency, 
Region 2, 290 Broadway, New York, NY 10007-1866.
    Any person may request a hearing on this proposed decision by 
filing a request to the Director, of the Division of Environmental 
Planning and Protection (DEPP), Environmental Protection Agency, Region 
2, 290 Broadway, New York, NY 10007-1866.

FOR FURTHER INFORMATION CONTACT: For technical information concerning 
this document, contact Ernst J. Jabouin at the address above or at 212-
637-4104. The RCRA regulatory docket for this proposed rule is located 
at the EPA Region 2, 290 Broadway, New York, NY 10007-1866, and is 
available for viewing from 8 a.m. to 4 p.m., Monday through Friday, 
excluding federal holidays. Call Ernst J. Jabouin at 212-637-4104 for 
appointments. The public may copy material from the regulatory docket 
at $0.15 per page.

SUPPLEMENTARY INFORMATION:
I. Overview Information
    A. What action is EPA proposing?
    B. Why is EPA proposing to approve this delisting?
    C. How will GE manage the waste if it is delisted?
    D. When would EPA finalize the proposed delisting?
    E. How would this action affect the states?
II. Background
    A. What is the history of the delisting program?
    B. What is a delisting petition, and what does it require of a 
petitioner?
    C. What factors must EPA consider in deciding whether to grant a 
delisting petition?
III. EPA's Evaluation of the Waste Information and Data
    A. What wastes did GE petition EPA to delist?
    B. What information and analyses did GE submit to support this 
petition?
    C. How did GE generate the petitioned waste?
    D. How did GE sample and analyze the data in this petition?
    E. What were the results of GE's analysis?
IV. Methodology for Risk Assessments
    A. How did EPA evaluate the risk of delisting this waste?
    B. What risk assessment methods has the Agency used in previous 
delisting determinations that are being used in this proposal?
V. Evaluation of This Petition
    A. What other factors did EPA consider in its evaluation?
    B. What did EPA conclude about GE's analysis?
    C. What is EPA's evaluation of this delisting petition?
VI. Conditions for Exclusion
    A. What are the maximum allowable concentrations of hazardous 
constituents for the waste?
    B. What are the conditions of the exclusion?
    C. What happens if GE fails to meet the conditions of the 
exclusion?
VII. Regulatory Impact
VIII. Regulatory Flexibility Act
IX. Paperwork Reduction Act
X. Unfunded Mandates Reform Act
XI. Executive Order 12875
XII. Executive Order 13045
XIII. Executive Order 13084
XIV. Executive Order 13132
XV. National Technology Transfer and Advancement Act

I. Overview Information

A. What Action Is EPA Proposing?

    The EPA is proposing to grant GE's petition to have its wastewater 
treatment sludge excluded, or delisted, from the definition of a 
hazardous waste. The Agency evaluated the petition using a fate and 
transport model to predict the concentration of hazardous constituents 
which could be released from the petitioned waste after it is disposed.

B. Why Is EPA Proposing To Approve This Delisting?

    GE petitioned EPA to exclude, or delist, the wastewater treatment 
sludge because GE believes that the petitioned waste does not meet the 
criteria for which EPA listed it. GE also believes there are no 
additional constituents or factors that could cause the wastes to be 
hazardous. Based on EPA's review described below, the Agency has 
tentatively determined that the waste can be considered nonhazardous.
    In reviewing this petition, EPA considered the original listing 
criteria and the additional factors as required by the Hazardous and 
Solid Waste Amendments of 1984 (HSWA). See section 222 of HSWA, 42 
U.S.C. 6921(f), and 40 CFR 260.22 (d)(2) through (4). EPA evaluated the 
petitioned waste against the listing criteria and factors cited in 40 
CFR 261.11(a)(2) and (3).

[[Page 12996]]

    The Agency also evaluated the waste for other factors including (1) 
the toxicity of the constituents; (2) the concentration of the 
constituents in the waste; (3) the tendency of the hazardous 
constituents to migrate and to bioaccumulate; (4) persistence in the 
environment of any constituents released from the waste; (5) plausible 
and specific types of management of the petitioned waste; (6) the 
quantity of waste produced; and (7) waste variability.
    EPA believes that the petitioned waste does not meet the criteria 
for which the waste was listed, and has tentatively decided to delist 
this waste from the former RCA del Caribe Facility.

C. How Will GE Manage the Waste If It Is Delisted?

    If the petitioned waste is delisted, GE must dispose of it in a 
Subtitle D landfill which is permitted, licensed, or registered by a 
state (as used herein includes the Commonwealth of Puerto Rico) to 
manage industrial waste. This exclusion does not change the regulatory 
status of the drying beds and on-site basins at the facility in 
Barceloneta, Puerto Rico where the waste has been disposed.

D. When Would EPA Finalize the Proposed Delisting?

    HSWA specifically requires EPA to provide notice and an opportunity 
for comment before granting or denying a final exclusion. Thus, EPA 
will not make a final decision or grant an exclusion until it has 
addressed all timely public comments (including those at public 
hearings, if any) on today's proposal.
    Since this rule would reduce the existing requirements for persons 
generating hazardous wastes, the regulated community does not need a 
six-month period to come into compliance in accordance with section 
3010 of RCRA as amended by HSWA. Therefore, the exclusion would become 
effective upon finalization.

E. How Would This Action Affect the States?

    Because EPA is issuing today's exclusion under the federal RCRA 
delisting program, only states subject to federal RCRA delisting 
provisions would be affected. This exclusion may not be effective in 
states having a dual system that includes federal RCRA requirements and 
their own requirements, or in states which have received authorization 
to make their own delisting decisions (note that the term ``State'' as 
used herein includes the Commonwealth of Puerto Rico).
    Under section 3009 of RCRA, EPA allows states to impose their own 
non-RCRA regulatory requirements that are more stringent than EPA's. 
These more stringent requirements may include a provision that 
prohibits a federally issued exclusion from taking effect in the state.
    Because a dual system (that is, both federal (RCRA) and state (non-
RCRA) programs) may regulate a petitioner's waste, we urge petitioner 
to contact the state regulatory authority to establish the status of 
its wastes under the state law.
    EPA has also authorized some states to administer a delisting 
program in place of the federal program, that is, to make state 
delisting decisions. Therefore, this exclusion does not apply in those 
authorized states. If GE transports the petitioned waste to or manages 
the waste in any state with delisting authorization, GE must obtain a 
delisting from that state before it can manage the waste as 
nonhazardous in the state.

II. Background

A. What Is the History of the Delisting Program?

    The EPA published an amended list of hazardous wastes from 
nonspecific and specific sources on January 16, 1981, as part of its 
final and interim final regulations implementing section 3001 of RCRA. 
The EPA has amended this list several times and published it in 40 CFR 
261.31 and 261.32.
    The Agency lists wastes as hazardous because: (1) they typically 
and frequently exhibit one or more of the characteristics of hazardous 
wastes identified in subpart C of part 261 (that is, ignitability, 
corrosivity, reactivity, and toxicity) or (2) they meet the criteria 
for listing contained in Sec.  261.11(a)(2) or (3).
    Individual waste streams may vary depending on raw materials, 
industrial processes, and other factors. Thus, while a waste described 
in these regulations generally is hazardous, a specific waste from an 
individual facility meeting the listing description may not be.
    For this reason, 40 CFR 260.20 and 260.22 provide an exclusion 
procedure, called delisting, which allows a person to demonstrate that 
EPA should not regulate a specific waste from a particular generating 
facility as a hazardous waste.

B. What Is a Delisting Petition, and What Does It Require of a 
Petitioner?

    A delisting petition is a request from a facility to EPA or an 
authorized state to exclude waste generated at a particular facility 
from the list of hazardous wastes.
    In a delisting petition, the petitioner must show the waste 
generated does not meet any of the criteria for listed wastes and does 
not exhibit any of the hazardous waste characteristics in 40 CFR part 
261, subpart C. The criteria for which EPA lists a waste are in 40 CFR 
261.11 and in the background documents. The petitioner must also 
present sufficient information to determine whether factors other than 
those for which the waste was listed warrant retaining it as a 
hazardous waste. (See 40 CFR 260.22, 42 U.S.C. 6921(f) and the 
background documents for the listed wastes).
    A generator remains obligated under RCRA to confirm that its waste 
remains nonhazardous based on the hazardous waste characteristics even 
if EPA has ``delisted'' the waste.

C. What Factors Must EPA Consider in Deciding Whether To Grant a 
Delisting Petition?

    EPA must also consider as a hazardous waste, a mixture containing 
listed hazardous wastes and wastes derived from treating, storing, or 
disposing of a listed hazardous waste. See 40 CFR 261.3(a)(2)(iv) and 
(c)(2)(i), called the ``mixture'' and ``derived-from'' rules, 
respectively. These wastes are also eligible for exclusion and remain 
hazardous wastes until excluded.
    The ``mixture'' and ``derived-from'' rules are now final, after 
having been vacated, remanded, and reinstated.

III. EPA's Evaluation of the Waste Information and Data

A. What Wastes Did GE Petition EPA To Delist?

    On November 20, 1997, GE petitioned EPA Region 2 to exclude an 
estimated volume of hazardous wastes ranging from 5,000 to 15,000 cubic 
yards from the list of hazardous wastes contained in 40 CFR 261.31. 
These wastes were generated and disposed of at GE's facility in 
Barceloneta, PR, formerly known as the RCA del Caribe facility. This 
facility is included on EPA's National Priority List and was the 
subject of a Superfund Remedial Investigation, Feasibility Study and 
Record of Decision. The wastes are described in GE's petition as EPA 
Hazardous Waste Number F006 wastewater treatment sludge that was 
generated from chemical etching operation and accumulated in two drying 
beds and two basins where the sludge mixed with soil. F006 is defined

[[Page 12997]]

as ``Wastewater treatment sludges from electroplating operations except 
from the following processes: (1) Sulfuric acid anodizing of aluminum; 
(2) tin plating on carbon steel; (3) zinc plating (segregated basis) on 
carbon steel; (4) aluminum or zinc-aluminum steel; (5) cleaning/
stripping associated with tin, zinc and aluminum plating on carbon 
steel; and (6) chemical etching and milling of aluminum.'' The 
constituents of concern for which F006 is listed are cadmium, 
hexavalent chromium, nickel and complexed cyanide.

B. What Information and Analyses Did GE Submit To Support This 
Petition?

    To support its petition, GE submitted (1) descriptions and 
schematic diagrams of its manufacturing and wastewater treatment 
processes, including historical information on past waste generation 
and management practices; (2) detailed chemical and physical analysis 
of the sludge (see section III.D.); and (3) environmental monitoring 
data from past and recent studies of the facility, including 
groundwater data from wells located around the two drying beds and two 
basins. GE submitted a signed certification of accuracy and 
responsibility statement set forth in 40 CFR 260.22(i)(12). By this 
certification, GE attests that all submitted information is true, 
accurate and complete.

C. How Did GE Generate the Petitioned Waste?

    According to information submitted by GE, the RCA del Caribe, Inc. 
Barceloneta facility began generating wastewater treatment sludge from 
its chemical etching operation in 1971 until the plant ceased 
operations in April 1987. During that time, the facility manufactured 
aperture (or shadow) masks for television picture tubes. A shadow mask 
is a specially prepared, paper thin, carbon steel screen used in 
cathode ray tubes to direct the electron beam to the television screen. 
The shadow masks were manufactured using a photolithographic/chemical 
etching process with the photolithographic step to establish locations 
of holes and slots and the chemical etching step to produce the desired 
holes and slots. During the process thin sheets of carbon steel which 
contained a thin layer of grease to protect the metal from corrosion 
and rusting were rinsed with tap water, detergent, caustic cleaning 
solution (sodium hydroxide), and deionized water. Rinses generated from 
this process were directed to the wastewater treatment plant. Then, a 
photoresist solution or glazing glue composed of casein, potassium or 
ammonium dichromate and a disinfectant (Borax) was baked to the surface 
of the clean sheet of steel. Once this process known as sensitizing is 
performed, the sheet was exposed to Ultra violet (UV) light to 
photographically develop the mask pattern. Developing or rinsing the UV 
exposed sheets with deionized water to remove unexposed photoresist 
solution from the sheets to exposed bare portions to be etched upon 
application of a wetting agent and oven-drying the sheet. These 
wastewaters, which contained unreacted photoresist solution, were 
directed to the wastewater treatment plant and were a source of 
chromium (from chromium dichromate) for the influent to the treatment 
plant and the resulting sludge. A mixture of hydrochloric acid and 
ferric chloride was used to chemically etch holes and slots in 
unprotected steel sheet portions. During the reaction, ferric ion 
(Fe+3) reacted with metallic ion (Fe+0) to 
produce ferrous ion (Fe+2) as follows:

2 Fe+3 + Fe+0 =3 Fe+2

    Spent ferric chloride etching solution was recovered for reuse in a 
closed-loop system. Final rinsing followed the etching process. Rinsed 
water from this step contained chromium, ferric chloride, and ferrous 
chloride and were directed to the wastewater treatment plant.
    The manufacturing process contributed to a chromium-reducing 
environment such that hexavalent chromium, or Cr(VI) would normally be 
reduced to trivalent chromium, or Cr(III). Because the etching solution 
was recovered and recycled in a closed loop system, it accumulated 
excess ferrous ions which were periodically converted elsewhere in the 
loop system to ferric ion by adding chloride.

3 Fe+2 + 3/2 Cl2=3 Fe+3 + 3 
Cl

However, for safety reasons, the regeneration was not allowed to go to 
completion. Excess chlorine in the etching solution would have evolved 
into hazardous chlorine gas. Therefore, some residual ferrous ion was 
always left in the regenerated solution. The ramification is that at 
low pH, the Eh (redox potential) of a solution containing both ferrous 
and ferric ions lies within a narrow range in which Cr (III) is stable, 
and Cr(VI) is not. Thus, any chromium in the excess etchant solution 
was trivalent, not hexavalent.
    All the wastewaters described above were blended prior to 
treatment. This results in reduction of hexavalent chromium to 
trivalent chromium species. The combined stream was pumped to the 
wastewater treatment plant where it was treated with caustic soda to 
effect precipitation of metals, chiefly ferric dioxide. A polymer was 
added to the metal in a clarifier. Clarified effluent flowed by gravity 
into a permitted natural sinkhole while the sludge underflow was 
discharged by gravity to two on-site sludge drying beds and two basins 
referred to by GE as ``surface impoundments'' (SI).

D. How Did GE Sample and Analyze the Data in This Petition?

    GE analyzed the drying beds sludge, basins sludge, basins soil and 
groundwater samples from the monitoring well network for hazardous 
constituents listed in 40 CFR part 264, appendix IX and for other 
parameters.
    GE's sampling strategy for contaminants consisted of dividing each 
drying beds and each basin surface area into four equal quadrants. 
Composite samples were collected from each quadrant. Each composite 
sample within that quadrant was composed of samples from five shallow 
borings and five grab samples for the surface composite samples. The 
borings and composite grab samples were located at the center and five 
to fifteen feet from the center (toward the corner), of each quadrant. 
Each boring sample was collected by making a composite of the entire 
thickness of the sludge representing the total depth of the unit 
sampled. The grab samples were collected from the surface to 0.5 feet. 
Contaminated soil around the basins were sampled in a fashion similar 
to what is described above for both surface and borings soil samples. 
The Agency evaluated the petitioned waste using these samples in 
combination with data from the Remedial Investigation.
    To quantify the total constituent and leachate concentrations, GE 
used the Contract Laboratory Program Scope of Work, (CLP SOW, April 
1990) and SW-846 Methods 6010/7000 series: for arsenic, barium, 
cadmium, chromium, hexavalent chromium, lead, mercury, nickel, 
selenium, and silver; 8240 for Appendix IX Volatile Organic Compounds 
(VOCs); 8270 for Appendix IX Semi-Volatile Organic Compounds (SVOCs); 
GE used these methods along with the Toxicity Characteristic Leaching 
Procedure (TCLP), (SW-846 Method 1311) to determine leachate 
concentrations of metals, VOCs, and SVOCs. Characteristic testing of 
soil and sludge samples also included analysis of ignitability (SW-846 
Method 1010) and corrosivity (SW-846 Method 9095).

E. What Were the Results of GE's Analysis?

    The maximum total and leachate concentrations for toxicity 
characteristic metals and nickel, total cyanide in GE's

[[Page 12998]]

waste samples are summarized in Table 1. Since none of the sludge 
samples failed for toxicity, no soil samples were subjected to TCLP 
leachate analysis. Also, there was no detection of significant 
concentrations of organics in either the soil or the sludge when 
analyzed for ``Appendix 9 constituents.'' As a result, neither the 
sludge nor the soil were subjected to TCLP organic analysis. EPA does 
not generally verify submitted test data before proposing delisting 
decisions. The sworn affidavit submitted with the petition binds the 
petitioner to present truthful and accurate results.

                                                     Table 1
----------------------------------------------------------------------------------------------------------------
                                  Maximum observed total concentration  (mg/kg)     Maximum observed Leachate
                                ------------------------------------------------    concentration  (mg/L TCLP)
                                                                                --------------------------------
                                  Sludge drying     Sludge SI      Soil around    Sludge drying      Sludge SI
                                      beds           basins          basins            beds           basins
----------------------------------------------------------------------------------------------------------------
Arsenic........................          17.4J            27.4           91.0             0.022           ND
Barium.........................          21.1             38.6          140               0.432            0.716
Cadmium........................          ND                1.2            3.0            ND               ND
Chromium.......................        5360             8400           4370               0.157           ND
Lead...........................          ND             677J             94.3J           ND               ND
Mercury........................           1.1J             1.6            0.49           ND               ND
Nickel.........................          43.3J           94J             64.4J            0.0214          ND
Selenium.......................           0.30J           ND              0.61J          ND               ND
Silver.........................          26.4J             0.66          22.1            ND               ND
Cyanide........................          ND               46.5           ND              ND               ND
 
----------------------------------------------------------------------------------------------------------------
Note: ND=Not Detected
J=value is an estimated quantity.

IV. Methodology for Risk Assessments

A. How Did EPA Evaluate the Risk of Delisting This Waste?

    For this delisting determination, EPA used information gathered to 
identify plausible exposure routes (i.e., groundwater, surface water, 
air) to hazardous constituents present in the petitioned waste. EPA 
estimated the risk posed by the waste if disposed of in an unlined 
Subtitle D landfill which, under a plausible mismanagement scenario, 
did not receive daily cover for 30 days at a time. Constituents of 
concern are assumed to migrate to a receptor through groundwater, air, 
and surface water routes. EPA used a Windows based software tool, the 
Delisting Risk Assessment Software Program (DRAS) developed by Region 
6, to estimate the potential releases of waste constituents and to 
predict the risk associated with those releases. A detailed description 
of DRAS and the fate, transport and risk models it uses follows.
1. Introduction
    During a delisting determination, the Agency uses risk assessment 
methodologies to predict the concentration of hazardous constituents 
released from the petitioned waste after disposal to determine the 
potential impact on human health and the environment. The DRAS program 
has been used to estimate the potential releases of waste constituents 
to waste management units. The program also predicts the risk 
associated with exposure to those releases using fate and transport 
mechanisms to predict releases and risk assessment algorithms to 
estimate adverse effects from exposure to those chemical releases. The 
DRAS computes chemical-specific exit values or ``delisting levels.'' 
The delisting levels are calculated using modeled, medium-specific 
chemical concentrations and standard EPA exposure assessment and risk 
characterization algorithms. EPA detailed all chemical release, 
exposure, and risk characterization methodologies in the EPA Region 6 
RCRA delisting Technical Support Document.
    The Agency has used the maximum estimated annual waste volume and 
the maximum reported leachate and total waste constituent 
concentrations as the input data into the DRAS program to generate 
compliance point concentrations and estimate risk. The compliance point 
is the location of an individual exposed to potential releases of 
delisted wastes for the purpose of evaluating risk. Compliance point 
concentrations are generated in a two-part process. First, the DRAS 
back-calculates a waste constituent concentration that an individual 
(receptor) may be exposed to without unacceptable risk. Then, knowing 
the maximum concentration permitted at the compliance point, the fate 
and transport models are used to back-calculate the maximum permissible 
concentration at the waste management unit that could be disposed of 
without exceeding the compliance point concentration.
    The risk assessment performed by the DRAS program which underlies 
the proposed rule is based upon a comprehensive approach to evaluating 
the movement of waste constituents from their waste management units, 
through different routes of exposure or pathways, to the points where 
human and ecological receptors are potentially exposed to these 
constituents. This risk assessment is being used in today's proposed 
rule to determine whether the petitioned RCRA listed waste can be 
defined as ``low-risk'' waste, able to exit the Subtitle C system and 
be managed in Subtitle D units. Low risk wastes are generally defined 
by Region 2 as wastes with a cancer risk of no more than 1 x 
10-6 or a hazard quotient of no more than 1.0. A cancer risk 
of 1 x 10-6 indicates a one in 1,000,000 probability of an 
individual developing cancer over a lifetime. For noncarcinogenic 
chemicals, a hazard quotient of one represents potential exposure equal 
to the safe toxicity threshold value. The program back-calculates 
allowable waste constituent concentrations at the selected risk levels.
    Although the pathway of ingestion of contaminated groundwater may 
be appropriate to propose exit levels for some wastes and constituents, 
it may not be protective for others, depending on the physical and 
chemical properties of each waste constituent. Some constituents have a 
high potential to bioaccumulate or bioconcentrate in living organisms. 
Pathways in which

[[Page 12999]]

these constituents come in contact with fish would be important to 
evaluate.
    The DRAS program performs an extensive risk assessment that 
examines numerous exposure pathways, rather than just the groundwater 
ingestion pathway. The DRAS program evaluates exposures associated with 
managing wastes in Subtitle D landfills or surface impoundments. 
Elements of the risk assessment procedure performed by the DRAS that 
support this proposal have undergone review by the Science Advisory 
Board (SAB) and EPA's Office of Research and Development (ORD). The use 
of the Composite Model for leachate migration with Transformation 
Products (CMTP) as used in the DRAS was favorably received by the SAB. 
ORD reviewed all other aspects of the DRAS program and responded 
favorably with comments. All ORD comments were addressed and 
incorporated into the DRAS program.
2. What Conditions Does the Agency Use in Determining Whether a Waste 
May Be Delisted?
    The EPA's approach in RCRA delisting risk analyses has typically 
been to represent a reasonable worst-case waste disposal scenario for 
the petitioned waste rather than use of site-specific factors. The 
Agency believes that a reasonable worst-case scenario results in 
conservative values for the compliance point concentrations and is 
appropriate when determining whether a waste should be relieved of the 
management constraints of RCRA Subtitle C. Site-specific factors (e.g., 
site hydrogeology) are not considered because a delisted waste is no 
longer subject to hazardous waste control, and therefore, the Agency is 
generally unable to predict and does not control where and how a waste 
will be managed after delisting. However, the Agency may impose 
conditions for exclusion so that the delisted waste is still managed in 
a manner that is protective of human health and the environment (refer 
to section VI.B. of this preamble).
3. How Is the Risk Assessment in the DRAS Program Structured?
    The assessment estimated the risk associated with constituent-
specific concentrations in the petitioned waste at the management unit 
that could be expected to result in an acceptable exposure to human or 
ecological receptors (determined through using the toxicity benchmarks 
such as reference doses--RfDs). The risk assessment took into account 
the various pathways by which waste constituents may move through the 
environment from the waste management unit to a receptor. The DRAS uses 
the fate and transport mechanisms to predict waste constituent 
movement. The potential exposure pathways considered in the assessment 
are not all-inclusive, but were selected to reflect those that might be 
commonly associated with the management of wastes in Subtitle D units. 
The management units could potentially be located in the range of 
environments that exist across the United States. Various environments 
have differing characteristics (e.g., meteorological conditions, soil 
type) with some environments more conducive for the movement of certain 
constituents in certain pathways. Conditions resulting in a 
conservative evaluation were used for each pathway, regardless of 
whether or not these conditions are likely to occur simultaneously at 
any one location. The assessment was structured using a deterministic 
approach. A deterministic approach uses a single, point estimate of the 
value of each input or parameter and calculates a single result based 
on those point estimates. The assessment used the best data available 
to select typical (i.e., approximately 50th percentile) and high-end 
(i.e., approximately 90th percentile) values for each parameter. The 
DRAS code which performs the assessment is constructed as a set of 
calculations that begin with an acceptable exposure level for a 
constituent to a receptor, and back-calculates to a waste constituent 
concentration in the management unit that corresponds to the acceptable 
risk level.
    The steps of the assessment which provide estimates of acceptable 
constituent-specific concentrations in waste include the following:
    Step 1--Specify acceptable risk levels for each constituent and 
each receptor.
    Step 2--Specify the exposure medium. Using the toxicity benchmarks 
as a starting point and the exposure equations, the assessment back 
calculates the concentration of contaminant in the medium (e.g., air, 
water, soil) that corresponds to ``acceptable'' exposure at the 
specified risk level. The exposure equations coded into the DRAS 
software include a quantitative description of how a receptor comes 
into contact with the contaminant and how much the receptor takes in 
through specific mechanisms (e.g., ingestion, inhalation, dermal 
adsorption) over some specified period of time.
    Step 3--Calculate the point of release concentration from the 
exposure concentration. Based on the back-calculated concentration in 
the exposure medium (from Step 2), the concentration in the medium to 
which the contaminant is released to the environment (i.e., air, soil, 
groundwater) for each pathway/receptor was modeled. The end result of 
this calculation is a waste constituent concentration at the point of 
release from the waste management unit (where the exempted waste is 
disposed) that will not result in adverse effects to human health and 
the environment.
4. When Assessing the Risk of the Exempted Waste, Where Does the DRAS 
Assume the Waste is Deposited?
    The DRAS risk assessment evaluates risks associated with petitioned 
RCRA wastes deposited to two waste management scenarios: landfills and 
surface impoundments. A landfill waste management scenario is used for 
the evaluation of solid wastes, while a surface impoundment waste 
management scenario is used for the evaluation of liquid wastes. The 
determination of whether a waste is a liquid waste is made using EPA 
approved Test Method 9095, referred to as the Paint Filter Test. Data 
to characterize landfills were obtained from a 1987 nationwide survey 
of industrial Subtitle D landfills. For releases to groundwater, EPA's 
Composite Model for leachate migration with Transformation Products 
(EPACMTP) fate and transport model was used by DRAS. The model assumes 
that solid wastes remain uncovered for thirty days after disposal and 
that the landfill will finally be covered with a 2-foot-thick native 
soil layer. The Subtitle D landfill is assumed to be unlined or if 
lined, that any liner at the base of the landfill will eventually 
completely fail.
    The DRAS assumes that liquid industrial wastes are disposed of in 
an unlined surface impoundment with a sludge or sediment layer at the 
base of the impoundment and that releases of contaminants originate 
from the surface impoundment. The surface impoundment is taken to have 
a 20-year operational life. After this period, the impoundment may be 
filled in, or simply abandoned. In either case, the remaining waste in 
the impoundment will leach into the unsaturated zone relatively 
quickly. Therefore, the duration of the leaching period in the modeling 
analysis is set equal to 20-years.
5. What Types of Chemical Releases From the Waste Management Units Does 
the DRAS Evaluate?
    The DRAS evaluates chemical releases of waste constituents from the 
waste management units to air, surface runoff and ground water. Using 
the

[[Page 13000]]

EPACMTP fate and transport model, DRAS evaluates the potential release 
of waste contaminants to the ground water. In this evaluation, the 
differences between waste management units are represented by different 
values or frequency distributions of the source-specific parameters. 
Source-specific parameters used by the EPACMTP predict releases to the 
ground water from landfills include:

Capacity and dimensions of the waste management unit;
Leachate concentration;
Infiltration and recharge rates;
Pulse duration;
Fraction of hazardous waste in the waste management unit;
Density of the waste and;
Concentration of the chemical constituent in the hazardous waste

    The source-specific parameters used by the model for surface 
impoundments include:

The area;
The ponding depth (such as the depth of liquid in the impoundment) and;
The thickness and hydraulic conductivity of the sludge or sediment 
layer at the bottom of the impoundment

    Data on the areas, volumes, and locations of waste management units 
were obtained from the 1987 EPA Survey of Industrial Subtitle D waste 
facilities in the United States. Derivation of the parameters for each 
type of waste management unit is described in the EPACMTP Background 
Document and User's Guide.
    For finite-source scenarios, simulations are performed for 
transient conditions, and the source is assumed to be a pulse of finite 
duration. In the case of landfills, the pulse duration is based on the 
initial amount of contaminant in the landfill, infiltration rate, 
landfill dimensions, waste and leachate concentration, and waste 
density. For surface impoundments, the duration of the leaching period 
is determined by the waste management unit's lifetime (the default 
value is 20 years). For a finite-source scenario, the model can 
calculate either the peak receptor well concentration for 
noncarcinogens or an average concentration over a specified period for 
carcinogens. The finite-source methodology in the EPACMTP is discussed 
in detail in the background document.
    The DRAS evaluates releases of waste constituents from the waste 
management to the air. Releases of chemicals to the air may be in the 
form of either particulates or volatile concentrations. Inhalation of 
particulates and their absorption into the lungs at the point of 
exposure (POE) and air deposition of particulates and subsequent 
ingestion of the soil-waste mixture at the POE are a function of 
particulate releases. The DRAS calculates particulate emissions 
resulting from wind erosion of soil-waste surfaces, from vehicular 
traffic, and from waste loading and unloading. To estimate the 
respirable particulate emissions resulting from wind erosion of 
surfaces with an infinite source of erodible particles, DRAS uses the 
methodology documented in Rapid Assessment of Exposure to Particulate 
Emissions from Surface Contamination Sites (RAEPE). The methodologies 
documented in Compilation of Air Pollutant Emission Factors, Volume 1: 
Stationary Point and Area Sources (AP-42) were employed to calculate 
the dust and particulate emissions resulting both from vehicular 
traffic and from waste loading and unloading operations at a facility.
    Particulate emission rates computed using these methodologies were 
summed and entered in the Ambient Air Dispersion Model, a steady-state, 
Gaussian plume dispersion model developed by EPA to predict the 
concentrations of constituents 1,000 feet downwind of a hypothetical 
land disposal facility. For a complete description and discussion, 
refer to the 1985 Ambient Air Dispersion Model (AADM). The model 
assumes that:

(1) The emission rate is constant over time;
(2) The emissions arise from an upwind virtual point source with 
emissions occurring at ground level and;
(3) No atmospheric destruction or decay of the constituent occurs

    The DRAS assumes typical or conservative values for all variables 
that are likely to influence the potential for soil erosion, including 
wind velocity and vegetative cover. The AADM unit dimension assumptions 
were modified to more closely resemble a landfill's. The DRAS equations 
compute emissions resulting from wind erosion, vehicular traffic, and 
waste loading and unloading. These equations are thoroughly described 
in the Region 6 delisting Technical Support Document. For the landfill 
waste disposal scenario, the DRAS assumed that no vegetative cover is 
present, thereby assuming enhanced erodability of soil or waste. The 
mean annual wind speed is assumed to be 4 meters per second. This value 
represents the average of the wind speeds registered at U.S. 
climatological stations as documented in Table 4-1 of RAEPE. The DRAS 
assumes a month's (30 days') worth of waste would be uncovered at any 
one time.
    Although particulates greater than 10 micrometers (um) in size 
generally are not considered respirable, the DRAS calculates the 
emission rate for particle sizes up to 30um in order to assess the 
potential impact of deposition and ingestion of such particulates using 
the distributions of wind-eroded particulates presented in RAEPE. 
Specifically, these distributions indicate that the release rate for 
particulates up to 30 um in size should be approximately twice the 
release rate calculated for particulates 10 um in size. The DRAS 
calculates the total annual average emissions of respirable 
particulates by summing for wind erosion, for vehicle travel, and for 
waste loading and unloading operations. The DRAS evaluates air 
deposition of the annual total emissions of particulates less than or 
equal to 30 um in size to soil 1,000 feet from the edge of a disposal 
unit. DRAS calculates the resulting soil concentration after one year 
of accumulation, conservatively assuming no constituent removal (no 
leaching, volatilization, soil erosion, or degradation).
    The DRAS also evaluates the atmospheric transport and inhalation of 
volatile constituents which was developed by EPA's Office of Air 
Quality Planning and Standards (OAQPS) and has been recommended for use 
in risk assessments conducted under the Superfund program. The DRAS 
program, is currently being revised to incorporate Shen's modification 
of Farmer's equation which will result in a better estimate of volatile 
emissions. Estimates of emissions of VOCs from disposal of wastewaters 
in surface impoundments are computed with EPA's Surface Impoundment 
Modeling System (SIMS). SIMS was developed by EPA's OAQPS. Further 
information can be found in the Background Document for the Surface 
Impoundment Modeling System Version 2.0. The volatile emission rates 
derived from the respective waste management scenario are used by the 
AADM steady-state Gaussian plume dispersion model to predict the 
concentrations of constituents 1,000 feet downwind of a hypothetical 
disposal facility.
    The DRAS evaluates potential releases of waste constituents to 
accessible surface waters. Exposure through the surface water pathway 
results from erosion of hazardous materials from the surface of a solid 
waste landfill and transport of these constituents to nearby surface 
water bodies. The DRAS uses the universal soil loss equation (USLE) to 
compute long-term soil and waste

[[Page 13001]]

erosion from a landfill in which delisted waste has been disposed. The 
USLE is used to calculate the amount of waste that will be eroded from 
the landfill. In addition, the size of the landfill is computed using 
the waste volume estimate provided by the petitioner. The volume of 
surface water into which runoff occurs is determined by estimating the 
expected size of the stream into which the soil is likely to enter. The 
amount of soil delivered to surface water is calculated using a 
sediment delivery ratio. The sediment delivery ratio determines the 
percentage of eroded material that is delivered to surface water based 
on the assumption that some eroded material will be redeposited between 
the landfill and the surface water body. A distance of 100 meters (m) 
to the nearest surface water body is assumed. The DRAS program as used 
here is currently being revised to account for partitioning between 
water and suspended solids when the eroded waste enters the stream. 
Rainfall erosion factor values range from 20 to 550 per year. Values 
greater than 300 occur in only a small proportion of the southeastern 
United States. A value of 300 was chosen as a conservative estimate 
ensuring that a reasonable worst-case scenario is provided for most 
possible landfill locations. Soil erodibility factors range from 0.1 to 
0.69 ton per acre. A value of 0.3 was selected for the analysis, which 
is estimated to exceed 66% of all values assuming a normal 
distribution. One month's worth of waste is assumed to be left 
uncovered at any one time and thus would be readily transportable by 
surface water runoff. Other variables used by the DRAS to evaluate 
releases to surface waters employed conservative assumptions. DRAS 
multiply the total annual mass of eroded material by the sediment 
delivery ratio to determine the mass of soil and waste delivered to 
surface water.
    The predicted erosion capacity is gradually diluted as it mixes 
with nearby surface waters. DRAS selects a representative volume or 
flux rate of surface water based on stream order, which is a system of 
taxonomy for streams and rivers. A stream that has no other streams 
flowing into it is referred to as a first-order stream. Where two 
first-order streams converge, a second-order stream is created. Where 
two second-order streams converge, a third-order stream is created. 
Data indicate that second-order streams have an estimated flow rate of 
3.7 cubic feet per second. The second-order stream was selected for 
analysis as the smallest stream capable of supporting recreational 
fishing. Fifth-order streams were also chosen for analysis as the 
smallest streams capable of serving as community water supplies. Fifth-
order stream flow is estimated to be 380 cubic feet per second.
6. By What Means May an Individual Be Exposed to the Proposed Exempted 
Waste?
    An exposure scenario is a combination of exposure pathways through 
which a single receptor may be exposed to a waste constituent. 
Receptors may be human or other animal in an ecosystem. There are many 
potential exposure scenarios. The DRAS evaluated the risks of the 
proposed waste associated with the exposure scenarios most likely to 
occur as a result of releases from the waste management unit. Receptors 
may come into contact with delisted waste constituent releases from a 
waste management unit via two primary exposure routes, either (1) 
directly via inhalation or ingestion of water or (2) indirectly via 
subsequent ingestion of soil and foodstuffs (such as fish) that become 
contaminated by waste constituents through the food chain. Receptors 
may also be exposed to waste constituents released from a waste 
management unit to surface media (via volatilization to air or via 
windblown particulate matter) or to groundwater (via ingestion of 
groundwater). The exposure scenarios assessed by DRAS are generally 
conservative in nature and are not intended to be entirely 
representative of actual scenarios at all sites. Rather, they are 
intended to allow standardized and reproducible evaluation of risks 
across most sites and land use areas. Conservatism is incorporated to 
ensure protection of potential receptors not directly evaluated, such 
as special subpopulations. The recommended exposure scenarios and 
associated assumptions assessed by DRAS are reasonable and conservative 
and they represent a scientifically sound approach that allows 
protection of human health and the environment.
7. What Receptors Are Assessed for Risk From Exposure to the Proposed 
Exempted Waste?
    Adult and child residents are the two receptors evaluated in this 
analysis. The adult resident exposure scenario is evaluated to account 
for the combination of exposure pathways to which an adult receptor may 
be exposed in an urban or rural (nonfarm) setting. The adult resident 
is assumed to be exposed to waste constituents from an emission source 
through the following exposure pathways:

(1) Direct inhalation of vapors and particles;
(2) Ingestion of fish;
(3) Ingestion of drinking water from surface water sources;
(4) Ingestion of drinking water from groundwater sources;
(5) Dermal absorption from groundwater sources via bathing;
(6) Inhalation from groundwater sources via showering

    DRAS evaluates two exposure pathways for children: (1) dermal 
absorption while bathing with potentially contaminated groundwater and 
(2) the ingestion of soil containing contaminated particulates which 
have been emitted from the landfill and deposited on the soil. Child 
residents (1 to 6 years old) were not selected as receptors for the 
groundwater ingestion and inhalation pathways, the surface water 
pathways, or the direct air inhalation pathways because the adult 
resident receptor scenario has been found to be protective of children 
with regard to these pathways. There is no indication that children 
consume more drinking water or inhale more air per unit of body weight, 
factoring in the recognized exposure duration, than adults. Therefore, 
average daily exposure normalized to body weight would be identical for 
adults and children. Likewise, a child receptor was not included for 
the freshwater fish ingestion pathway because there is no evidence that 
children consume more fish relative to their body weight, factoring in 
exposure duration, than do adults. The dermal absorption while bathing 
with groundwater exposure pathway is evaluated differently for child 
residents than it is for adult residents because of the following 
considerations: (1) The ratio of exposed skin surface area to body 
weight is slightly higher for children than for adults, resulting in a 
slightly larger average daily exposure for children than for adults; 
and (2) the exposure duration for such children is limited to 6 years, 
thus lowering the lifetime average exposure to carcinogens. Typically, 
the adult scenario is more protective with regard to carcinogens 
(because of the longer exposure duration), and the child scenario is 
more protective with regard to noncarcinogens (because of the greater 
skin surface area to body weight ratio).
8. Where Does the DRAS Assume That Receptors Are Located When 
Performing the Risk Evaluation?
    The EPACMTP, a probabilistic groundwater fate and transport model, 
was used to predict groundwater constituent concentrations at a

[[Page 13002]]

hypothetical receptor well located downgradient from a waste management 
unit. This receptor well represents the POE. That is, the predicted 
waste constituent concentration at the POE is used to assess the risk 
of the proposed exempted waste. The distance to the well is based on 
the results of the 1987 nationwide survey of landfills conducted by 
EPA's Office of Solid Waste (OSW) which determined the distance to the 
nearest drinking water well downgradient from municipal landfills. The 
survey data are entered in the EPACMTP model as an empirical 
distribution: minimum = 0 m, median = 427 m, and maximum = 1,610 m 
(approximately 1 mile). In contrast to the 1990 Toxicity Characteristic 
(TC) Rule (55 FR 11798), there is no requirement that the well lie 
within the leachate plume.
    For carcinogenic waste constituents, the exposure concentration is 
defined as the maximum 30 year average receptor well concentration; for 
noncarcinogens, the exposure concentration is taken to be the highest 
receptor well concentration during the modeled 10,000 year period. A 
10,000 year limit was imposed on the exposure period; that is, the 
calculated exposure concentration is the peak or highest 30 year 
average concentration occurring within 10,000 years following the 
initial release from the waste management unit. The fate and transport 
simulation within the CMTP provided a probability distribution of 
receptor well concentrations as a function of expected leachate 
concentration. Using the receptor well concentrations as a function of 
the waste constituent concentration, the EPACMTP derived chemical-
specific dilution attenuation factors (DAFs) which convert a leachate 
concentration in the landfill to a groundwater concentration at the 
receptor well.
    Human exposure routes for surface water include ingestion of 
surface water used as drinking water and ingestion of fish from nearby 
surface water bodies. For the surface water ingestion exposure route, 
the surface water POE modeled is a fifth-order stream 100 m from the 
waste management unit. Fifth-order streams were chosen for analysis 
because EPA assumes that a fifth-order stream is the smallest stream 
capable of serving as a community water supply. The assumption of a 100 
m distance to the nearest surface water body is a conservative 
assumption based on available data. An EPA survey of municipal landfill 
facilities showed that 3.6 percent of the surveyed facilities are 
located within 1 mile of a river or stream and that the average 
distance from these facilities to the closest river or stream is 586 m 
(1,921 feet). For the fish ingestion exposure route, a second-order 
stream was chosen for analysis. This stream segment was determined to 
be the smallest stream capable of supporting fisheries. The POE in the 
surface water body for collection of fish is assumed to be 100 m 
downgradient from the disposal facility. Human exposure to emissions of 
windblown particulates from landfills and to emissions of volatiles 
from landfills and surface impoundments is assessed by the DRAS. For 
the air pathway, the DRAS assumes the POE is 305 m (1,000 feet) 
downwind of the waste management unit.
9. How Does DRAS Determine Rates of Exposure?
    The calculation of constituent-specific exposure rates for each 
exposure pathway evaluated were based on:

(1) The estimated concentration in a given medium as calculated in 
DRAS;
(2) The contact rate;
(3) Receptor body weight, and;
(4) The frequency and duration of exposure

    This calculation is repeated for each constituent and for each 
exposure pathway included in an exposure scenario. Exposure to 
hazardous constituents is assumed to occur over a period of time. To 
calculate an average exposure per unit of time, the DRAS divides the 
total exposure by the time period. Exposures are intended to represent 
reasonable maximum exposure (RME) estimates for each applicable 
exposure route. The RME approach is intended to combine upper-bound and 
mid-range exposure factors so that the result represents an exposure 
scenario that is both protective and reasonable, not the worst possible 
case.
10. What Rate of Contact With a Contaminated Media Does the DRAS Use?
    The contact rate is the amount of contaminated medium contacted per 
unit of time or event. Contact rates for subsistence food types (fish 
for the fish ingestion pathway) are assumed to be 100 percent from the 
hypothetical assessment area (surface water body). The following 
sections describe exposure pathway-specific contact rates.
11. What Are the Contact Rates at Which Individuals Are Exposed to 
Contaminated Media?
    For groundwater and surface water ingestion, the intake rate is 
assumed to be 2.0 liters per day (l/day), the average amount of water 
that an adult ingests. This value, which is currently used to set 
drinking water standards, is close to the current 90th percentile value 
for adult drinking water ingestion (2.3 l/day) reported in the EPA 
Exposure Factors Handbook. This value approximates the 8 glasses of 
water per day historically recommended by health authorities. The 
contact for the dermal exposure pathway is assumed to occur while 
bathing with contaminated groundwater. In this analysis, the DRAS 
assumes that the average adult resident is in contact with groundwater 
during bathing for 0.25 hour per event and that the average child 
resident is in contact with groundwater during bathing for 0.33 hour 
per event, with one event per day. For dermal bathing exposure to 
contaminated groundwater, the selected receptors are an adult and a 
young child (1 to 6 years old). During bathing, generally all of the 
skin surface is exposed to water. The total adult body surface area can 
vary from about 17,000 to 23,000 square centimeters (cm2). 
The EPA Exposure Factors Handbook (EFH) reports a value of 20,000 
cm2 as the median value for adult skin surface area. A value 
of 6,900 cm2 has been commonly used for a child receptor in 
EPA risk assessments; this value is approximately the average of the 
median values for male children aged 2 to 6. The EFH presents a range 
of recommended values for estimates of the skin surface area of 
children by age. The mean skin surface area at the median for boys and 
girls 5 to 6 years of age is 0.79 square meters (m2) or 
7,900 cm2. Given that the age for children is defined as 0 
to 6 years (see EFH Section 3.3.4), a skin surface area value for ages 
5 to 6 years would be a conservative estimate of skin surface area for 
children. For calculation of dermal exposure to waste constituents, the 
DRAS uses a value of 7,900 cm2 for the skin surface area of 
children and a value of 20,000 cm2 for the skin surface area 
of adults.
    For the groundwater pathway of inhalation exposure during 
showering, the contact with water is assumed to occur principally in 
the shower and in the bathroom. The DRAS analysis assumes that the 
average adult resident spends 11.4 minutes per day in the shower and an 
additional 48.6 minutes per day in the bathroom. Daily inhalation rates 
vary depending on activity, gender, age, and so on. Citing a need for 
additional research, the EFH does not recommend a reasonable upper-
bound inhalation rate value. The EFH recommended value for the average 
inhalation rate is 15.2 cubic meters per day (m3) for males 
and 11.3 m3 day for females. The EPA established an upper-

[[Page 13003]]

bound value for an individual's inhalation rate at 20 m3 day 
which has been commonly used in past EPA risk assessments. This value 
is used by the DRAS for assessment of inhalation exposure.
    The DRAS assesses the ingestion of soil contaminated with air-
deposited particulates from a nearby landfill. The potential for 
exposure to constituents via soil ingestion is greater for children 
because they are more likely to ingest more soil than adults as a 
result of behavioral patterns present during childhood. Therefore, 
exposure to waste constituents through ingestion of contaminated soils 
is evaluated for the child in a delisting risk assessment. The mean 
soil ingestion values for children range from 39 to 271 milligrams per 
day (mg/day), with an average of 146 mg/day for soil ingestion and 191 
mg/day for soil and dust ingestion (see EPA EFH). Based on the EFH 
statement that 200 mg/day may be used as a conservative estimate of the 
mean, the DRAS uses 200 mg/day as the soil ingestion rate for children.
    Fish consumption rates vary greatly, depending on geographic region 
and social or cultural factors. The recommended value for fish 
consumption for all fish is 0.28 grams of fish per kilogram body weight 
per day for an average adult (see EPA EFH). This value equates with a 
fish consumption rate of 20.1 grams per day (g/day) for all fish. The 
DRAS estimated that an exposed individual eats 20 g of fish per day, 
representing one 8-ounce serving of fish approximately once every 11 
days.
12. At What Frequency Does the DRAS Assume That Receptors Are Exposed 
to Contaminated Media?
    An exposure frequency of 350 days per year is applied to all 
exposure scenarios (see EPA EFH). Until better data become available, 
the common assumption that residents take 2 weeks of vacation per year 
is used to support a value of 15 days per year spent away from home, 
leaving 350 days per year spent at home and susceptible to exposure.
13. For What Duration Does the DRAS Assume Receptors Are Exposed to 
Contaminated Media?
    The exposure duration reflects the length of time that an exposed 
individual may be expected to reside near the constituent source. For 
the adult resident, this value is taken to be 30 years, and for the 
child resident, this value is taken to be 6 years (see EPA EFH). The 
adult resident is assumed to live in one house for 30 years, the 
approximate average of the 90th percentile residence times from two key 
population mobility studies. For the child resident, the exposure 
duration is assumed to be 6 years, the maximum age of the young child 
receptor. For carcinogens, exposures are combined for children (6 
years) and adults (24 years). For noncarcinogenic constituents, the 
averaging time (AT) equals the exposure duration in years multiplied by 
365 days per year. For an adult receptor, the exposure duration is 30 
years, and for a child receptor, the exposure duration is 6 years. For 
carcinogenic constituents, the AT has typically been 25,550 days, based 
on a lifetime exposure of 70 years at 365 days per year. The life 
expectancy value in the EFH is 75 years. Given this life expectancy 
value, the AT for a delisting risk assessment is 27,375 days, based on 
a lifetime exposure of 75 years at 365 days per year.
14. What Body Weights Are Assumed for Receptors in the DRAS Evaluation?
    Risk Assessment Guidance for Superfund defines the body weight of 
the receptor as either adult weight (70 kilograms (kg)) or child weight 
(1 to 6 years, 15 kg). The EFH recommended value of 71.8 kg for an 
adult differs from the 70-kg value commonly used in EPA risk 
assessments. In keeping with the latest EFH recommendation, the DRAS 
used a 72-kg adult weight and a 15-kg child weight for the proposed 
delisting determination.

B. What Risk Assessment Methods Has the Agency Used in Previous 
Delisting Determinations That Are Being Revised in This Proposal?

1. Introduction
    The fate and transport of constituents in leachate from the bottom 
of the waste unit through the unsaturated zone and to a drinking water 
well in the saturated zone was previously estimated using the EPA 
Composite Model for Landfill (EPACML) (See 55 FR 11798). The EPACML 
accounts for:

One-dimensional steady and uniform advective flow;
Contaminant dispersion in the longitudinal, lateral, and vertical 
directions;
Sorption.
    However, advances in groundwater fate and transport have been made 
in recent years and the Agency proposes the use of a more advanced 
groundwater fate and transport model for RCRA exclusions.
2. What Fate and Transport Model Does the Agency Use in the DRAS for 
Evaluating the Risks to Groundwater From the Proposed Exempted Waste?
    The Agency proposes to use the EPACMTP in this delisting 
determination. The EPACMTP considers the subsurface fate and transport 
of chemical constituents. The EPACMTP is capable of simulating the fate 
and transport of dissolved contaminants from a point of release at the 
base of a waste management unit, through the unsaturated zone and 
underlying groundwater, to a receptor well at an arbitrary downstream 
location in the aquifer. The model accounts for the following 
mechanisms affecting contaminant migration: transport by advection and 
dispersion, retardation resulting from reversible linear or nonlinear 
equilibrium adsorption onto the soil and aquifer solid phase, and 
biochemical degradation processes.
3. Why Is the EPACMTP Fate and Transport Model an Improvement Over the 
EPACML?
    The modeling approach used for this proposed rulemaking includes 
three major categories of enhancements over the EPACML. The 
enhancements include:

(1) Incorporation of additional fate and transport processes (e.g., 
degradation of chemical constituents);
(2) Use of enhanced flow and transport solution algorithms and 
techniques (e.g., three-dimensional transport) and;
(3) Revision of the probabilistic methodology (e.g., site-based 
implementation of available input data).

A discussion of the key enhancements which have been implemented in the 
EPACMTP is presented here and the details are provided in the proposed 
1995 Hazardous Waste Identification Rule (HWIR) background documents 
(60 FR 66344-December 21, 1995).
    The EPACML was limited to conditions of uniform groundwater flow. 
It could not handle accurately the conditions of significant 
groundwater mounding and non-uniform groundwater flow due to a high 
rate of infiltration from the waste units. These conditions increase 
the transverse horizontal as well as the vertical spreading of a 
contaminant plume. The EPACMTP accounts for these effects directly by 
simulating groundwater flow in the vertical as well as horizontal 
directions.
    The EPACMTP can simulate fate and transport of metals, taking into 
account geochemical influences on the mobility

[[Page 13004]]

of metals. The EPA's MINTEQA2 metals speciation model is used to 
generate effective sorption isotherms for individual metals, 
corresponding to a range of geochemical conditions. The transport 
modules in EPACMTP have been enhanced to incorporate the nonlinear 
MINTEQ sorption isotherms. This enhancement provides the model with 
capability to simulate, in the unsaturated and in the saturated zones, 
the impact of pH, leachate organic matter, natural organic matter, iron 
hydroxide and the presence of other ions in the groundwater on the 
mobility of metals. The saturated zone module implemented in the EPACML 
was based on a Gaussian distribution of concentration of a chemical 
constituent in the saturated zone. The module also used an 
approximation to account for the initial mixing of the contaminant 
entering at the water table underneath the waste unit. The approximate 
nature of this mixing factor could sometimes lead to unrealistic values 
of contaminant concentration in the groundwater close to the waste 
unit, especially in cases of a high infiltration rate from the waste 
unit. The enhanced model incorporates a direct linkage between the 
unsaturated zone and saturated zone modules which overcomes these 
limitations of the EPACML.
    To enable a greater flexibility and range of conditions that can be 
modeled, the analytical saturated zone transport module has been 
replaced with a numerical module, based on the highly efficient state-
of-the-art Laplace Transform Galerkin (LTG) technique. The enhanced 
module can simulate the anisotropic, non-uniform groundwater flow, and 
transient, finite source, conditions. The latter requires the model to 
calculate a maximum receptor well concentration over a finite time 
horizon, rather than just the steady state concentration which was 
calculated by the EPACML. The saturated zone modules have been 
implemented to provide either a fully three-dimensional solution, or a 
highly efficient quasi-3D solution. The latter has been implemented for 
probabilistic applications and provides nearly the same accuracy as the 
fully three dimensional option, but is more computationally efficient. 
Both the unsaturated zone and the saturated zone transport modules can 
accommodate the formation and the transport of parent as well as of the 
transformation products.
    A highly efficient semi-analytical unsaturated zone transport 
module has been incorporated to handle the transport of metals in the 
unsaturated zone and can use MINTEQA2 derived linear or nonlinear 
sorption isotherms. Conventional numerical solution techniques are 
inadequate to handle extremely nonlinear isotherms. An enhanced method-
of-characteristic based solution has been implemented which overcomes 
these problems and thereby enables the simulation of metals transport 
in the probabilistic framework. Non-linearity in the metals sorption 
isotherms is primarily of concern at higher concentration values; for 
low concentrations, the isotherms are linear or close to linear. 
Because of the attenuation in the unsaturated zone, and the subsequent 
dilution in the saturated zone, concentrations in the saturated zone 
are usually low enough so that properly linearized isotherms are used 
by the model in the saturated zone without significant errors.
    The internal routines in the model which determine placement of the 
receptor well relative to the areal extent of the contaminant plume 
have been revised and enhanced to eliminate bias which was present in 
the implementation in the EPACML. The calculation of the areal extent 
of the plume has been revised to take into consideration the dimensions 
of the waste unit. The logic for placing a receptor well inside the 
plume limits has been improved to eliminate a bias towards larger waste 
unit areas and to ensure that the placement of the well inside these 
limits, for a given radial distance from the unit, is truly randomly 
uniform. However, for this proposal, the closest drinking water well is 
located anywhere on the downgradient side of the waste unit.
    The data sources from which parameter distributions for nationwide 
probabilistic assessments are obtained have been evaluated, and where 
appropriate, have been revised to make use of the latest data available 
for modeling. Leachate rates for Subtitle D waste units have been 
revised using the latest version of the Hydrologic Evaluation of 
Landfill Performance (HELP) model with the revised data inputs. Source 
specific input parameters (e.g., waste unit area and volume) have been 
developed for various different types of industrial waste units besides 
landfills. Input values for the groundwater related parameters have 
been revised to utilize information from a nationwide industry survey 
of actual contaminated sites. The original version of the model was 
implemented for probabilistic assessments assuming continuous source 
(infinite source) conditions only. This methodology did not take into 
account the finite volume and/or operational life of waste units. The 
EPACMTP model has been implemented for probabilistic assessments of 
either continuous source or finite source scenarios. In the latter 
scenario, predicted groundwater impact is not only based on the 
concentrations of contaminants in the leachate, but also on the amount 
of constituent in the waste unit and/or the operational life of the 
unit.
    The landfill is taken to be filled to capacity and covered when 
leaching begins. The time period during which the landfill is filled-
up, usually assumed to be 20 years, is considered to be small relative 
to the time required to leach all of the constituent mass out of the 
landfill. The model simulation results indicate that this assumption is 
not unreasonable; the model calculated leaching duration is typically 
several hundred years. The leachate flux, or infiltration rate, is 
determined using the HELP model. The net infiltration rate is 
calculated using a water balance approach, which considers 
precipitation, evapo-transpiration, and surface run-off. The HELP model 
was used to calculate landfill infiltration rates for a representative 
Subtitle D landfill with 2-foot earthen cover, and no liner or leachate 
collection system, using climatic data from 97 climatic stations 
located throughout the US. These correspond to the reasonable worst 
case assumptions as explained in the HWIR Risk Assessment Background 
Document for the HWIR proposed notice (60 FR 66344--December 21, 1995). 
Additional details on the methodologies used by the EPACMTP to derive 
DAFs for waste constituents modeled for the landfill scenario are 
presented in the Background Documents for the proposed HWIR docket (60 
FR 66344--December 21, 1995). The fraction of waste in the landfill is 
assigned a uniform distribution with lower and upper limits of 0.036 
and 1.0, respectively, based on analysis of waste composition in 
Subtitle D landfills. The lower bound assures that the waste unit will 
always contains a minimum amount of the waste of concern. The waste 
density is assigned a value based on reported densities of hazardous 
waste, and varies between 0.7 and 2.1 grams per cubic centimeter (g/
cm[bs]3[bs]).
    The area of the surface impoundment and the impoundment depth used 
by the EPACMTP are obtained from the OSW Subtitle D Industrial Survey 
and were entered into the probabilistic analyses as distributions. The 
sediment layer at the base of the impoundment is taken to be 2 feet 
thick, and have an effective equivalent saturated conductivity of 
10-7 centimeters per second (cm/s). These values were 
selected in recognition of the fact that

[[Page 13005]]

most non-hazardous waste surface impoundments do have some kind of 
liners in place. Additional details on the methodologies used by the 
EPACMTP to derive DAFs for waste constituents modeled for the surface 
impoundment waste management scenario are presented in the Background 
Documents for the 1995 proposed HWIR docket (60 FR 66344--December 21, 
1995).
4. Has the EPACMTP Methodology Been Formally Reviewed?
    The Science Advisory Board (SAB), a public advisory group that 
provides information and advice to the EPA, reviewed the EPACMTP model 
as part of a continuing effort to provide improvements in the 
development and external peer review of environmental regulatory 
models. Overall, the SAB commended the Agency for making significant 
enhancements to the EPACMTP's predecessor (EPACML) and for responding 
to previous SAB suggestions. The SAB also concluded that the 
mathematical formulation incorporating transformation or degradation 
products into the model appeared to be correct and that the site-based 
approach using hydrogeologic regions is superior to the previous 
approach used in EPACML. The model underwent public comment during the 
1995 proposed HWIR (60 FR 66344--December 21, 1995).
5. Has the Agency Modified the EPACMTP as Utilized in the HWIR 
Proposal?
    The EPACMTP, as developed for HWIR, determined the DAF using a 
probabilistic approach that selected, at random, a waste volume from a 
range of waste volumes identified in EPA's 1987 Subtitle D landfill 
survey. In delisting determinations, the waste volume of the petitioner 
is known. Therefore, application of EPACMTP to the delisting program 
has been modified to evaluate the specific waste volume. The Agency 
modified the DAFs determined under the HWIR proposal to account for a 
known waste volume. To generate waste volume-specific DAFs, EPA 
developed ``scaling factors'' to modify DAFs developed for HWIR (based 
on the entire range of disposal unit areas) to DAFs for delisting waste 
volumes. This was accomplished by computing a 90th percentile DAF for a 
conservative chemical for 10 specific waste volumes (ranging from 1,000 
cu. yds. to 300,000 cu. yds.) for each waste management scenario 
(landfill and surface impoundment). The Agency assumed that DAFs for a 
specific waste volume are linearly related to DAFs developed by EPACMTP 
for the HWIR. DAF scaling factors were computed for the ten increment 
waste volumes. Using these ten scaling factor DAFs, regression 
equations were developed for each waste management scenario to provide 
a continuum of DAF scaling factors as a function of waste volume.
    The regression equations are coded into the DRAS program which then 
automatically adjusts the DAF for the waste volume of the petitioner. 
The method used to verify the scaling factor approach is presented in 
Application of EPACMTP to Region 6 delisting Program: Development of 
Volume-adjusted Dilution Attenuation Factors. For the landfill waste 
management scenario, the DAF scaling factors ranged from 9.5 for 10,000 
cu. yard to approximately 1.0 for waste volumes greater than 200,000 
cu. yards. Therefore, for solid waste volumes greater than 200,000 cu. 
yds., the waste volume-specific DAF is the same as the DAF computed for 
the proposed HWIR. The regression equation that can be used to 
determine the DAF scaling factor (DSF) as a function of waste volume 
(in cubic yards) for the landfill waste management unit is: DSF = 
6152.7 x (waste volume)-\0.7135\. The correlation 
coefficient of this regression equation is 0.99, indicating a good fit 
of this line to the data points. DAF scaling factors for surface 
impoundment waste volumes ranged from 2.4 for 2,000 cu. yards to 
approximately 1.0 for 100,000 cu. yds. For liquid waste volumes greater 
than 200,000 cu. yds., the waste volume-specific DAF is the same as the 
DAF computed for the proposed HWIR. The regression equation for DSF as 
a function of waste volume for surface impoundment wastes is: DSF = 
14.2 x (waste volume)-\0.2288\. The correlation coefficient 
of this regression equation is also 0.99, indicating an extremely good 
fit of this line to the data points.

V. Evaluation of This Petition

A. What Other Factors Did EPA Consider in Its Evaluation?

    We also consider the applicability of ground-water monitoring data 
during the evaluation of delisting petitions where the waste in 
question is or has ever been placed on land. In this case, the waste 
has been placed directly on soil or in contact with underlying clayey 
sand and limestone bedrock. A total of three groundwater sampling 
events has been conducted at the site from monitoring wells around the 
existing drying beds and basins which contain the waste and submitted 
to the Agency as part of the petition. Historical data showed sporadic 
detection of four inorganic constituents in the groundwater and 
indicated that the drying beds and basins waste was a possible source. 
However, a confirmation groundwater sampling event utilizing a more 
sophisticated EPA recommended sampling technique could not establish 
that hazardous substances were currently leaching from the drying beds 
and basins sludge as well as associated contaminated soil at levels 
exceeding those predicted by the EPACMTP model in the DRAS program. The 
evaluation was based on a statistical analysis conducted in accordance 
with Statistical Analysis of Ground-Water Monitoring Data at RCRA 
Facilities--Interim Final Guidance, EPA, April 1989 and Statistical 
Analysis of Ground-Water Monitoring Data at RCRA Facilities--Addendum 
to Interim Final Guidance, EPA, July 1992. Leachate analysis of sludge 
samples generally supported the conclusion that the beds and basins 
sludge was not currently a source of groundwater contamination above 
health-based levels.
    Specifically, chromium, lead, mercury and nickel were sporadically 
detected in groundwater. However, the sludge did not appear to be 
leaching these constituents to groundwater. Chromium, lead, and mercury 
are present in background samples. The highest concentration of these 
constituents were found in a single sample described as ``brown, 
turbid.'' None of them were detected in the filtered portion of that 
same sample. Nickel contamination could not be attributed to the sludge 
and was detected in only one quarterly sampling event. Furthermore, 
using low flow method in a confirmatory sampling event to account for 
turbidity, except for mercury which was slightly above the health base 
level, nickel was not detected and chromium and lead were detected 
below the level of concern. Therefore, the analytical results of 
groundwater show that elevated levels of mercury, nickel, chromium and 
lead historically detected in the groundwater at the site are 
attributable to naturally-occurring trace elements in fine sediments.

B. What Did EPA Conclude About GE's Analysis?

    The total cumulative risk posed by the waste, is approximately 3.66 
x 10-\6\. EPA believes that this risk is acceptable because 
the value is within a generally acceptable range of 1 x 
10-\4\ to 1 x 10-\6\ and the estimated risk is 
associated with a single contaminant. Specifically, ingestion of 
carcinogenic arsenic in groundwater contributes 3.66 x 
10-\6\; the surface water pathway contributes 3.11 x 
10-\9\. Cadmium, the other

[[Page 13006]]

contributor to the total risk and included only as a detection limit, 
has no groundwater ingestion risk and its surface water pathway 
contributes only 5.51 x 10-\15\ to the total level of risk.
    After reviewing GE's processes, the EPA concludes that (1) 
hazardous constituents of concern are present in GE's waste, but not at 
levels which are likely to pose a threat to human health and the 
environment when placed in a solid waste landfill; and (2) the 
petitioned waste does not exhibit any of the characteristics of 
ignitability, corrosivity, or reactivity. See 40 CFR 261.21, 261.22, 
and 261.23, respectively.

C. What is EPA's Evaluation of This Delisting Petition?

    The descriptions of the GE hazardous waste process and analytical 
characterization, with the proposed verification testing requirements 
(as discussed later in this document), provide a reasonable basis for 
EPA to grant the exclusion.
    The Agency has reviewed the sampling procedures used by GE and have 
determined they satisfy EPA criteria for collecting representative 
samples of constituent concentrations in the wastewater treatment 
sludge.
    EPA believes the data submitted in support of the petition show 
that GE's waste will not pose a threat when disposed of in a Subtitle D 
landfill regulated by a state. The Agency therefore, proposes to grant 
GE an exclusion for its WWTP sludge.
    If EPA finalizes the proposed rule, the Agency will no longer 
regulate the petitioned waste under 40 CFR parts 262 through 268 and 
the permitting standards of part 270.

VI. Conditions for Exclusion

A. What Are the Maximum Allowable Concentrations of Hazardous 
Constituents in the Waste?

    Table 2 below summarizes maximum observed TCLP concentrations in 
GE's waste, maximum allowable leachate levels for GE's waste, and the 
level of regulatory concern at the point of exposure for groundwater. 
The EPA calculated delisting levels for all constituents detected.
    Maximum allowable leachate concentrations (expressed as a result of 
the TCLP test) were calculated for all constituents for which leachate 
was analyzed. The allowable leachate concentrations were derived from 
the health-based calculation within the DRAS program. Maximum allowable 
leachate levels were also derived from MCLs, SDWA Treatment Technique 
(TT) action levels, or toxicity characteristic levels from 40 CFR 
261.24 if they resulted in a more conservative delisting level. The 
maximum allowable point of exposure groundwater concentrations 
correspond to the lesser of the health-based values calculated within 
the DRAS program or the MCLs or TT action levels.
    A statistical review of some of the data indicates that the maximum 
values used in the modeling and risk estimation correspond to a very 
high confidence interval. Assuming that the distribution of the data is 
adequately defined, future samples are likely to exhibit concentrations 
which are less than the maximum values used in this evaluation. All of 
the maximum waste concentrations observed are less than the 
corresponding delisting levels assigned.

                                                                         Table 2
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                             Maximum observed \1\  leachate concentration  (mg/l TCLP)                        Maximum
                                        ------------------------------------------------------------------    Maximum        allowable
                                                                                                             allowable       point of         Maximum
                                                                                                              leachate       exposure        allowable
                                                Sludge drying beds               Sludge SI  basins         concentration   concentration   TCLP base on
                                                                                                             (mg/l TCLP)     (mg/l in        MCL mg/l
                                                                                                                           groundwater)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Arsenic................................  0.0221                           ND(0.1)                                 0.0604           0.604           6.19
Barium.................................  0.432                            0.716                                 472           \2\358             359
Cadmium................................  ND                               ND(0.01)                                3.63          \2\0.965           0.967
Chromium...............................  0.157                            ND(0.01)                          1400000          \2\2480            2480
Lead...................................  ND                               ND(0.085)                             484              483             484
Mercury................................  ND                               ND(0.0002)                              0.219         \2\0.960           0.961
Nickel.................................  0.0214                           ND(0.04)                              182              182      ..............
Selenium...............................  ND                               ND(0.195)                              14             \2\0.748           3.74
Silver.................................  ND                               ND(0.01)                               24.8             24.8    ..............
Cyanide................................  ND                               ND(0.01)                               87.1          \2\23.2            23.2
--------------------------------------------------------------------------------------------------------------------------------------------------------
Note: ND=Not Detected (Detection Limit).
J=value is an estimated quantity.
\1\These levels represent the highest constituent concentration found in any one sample, not necessarily the specific levels found in one sample.
\2\The concentration is based on the MCL or TT action level.

    In addition to the delisting values in the table, several delisting 
levels based on total concentrations were also established for GE's 
waste. Table 3 below summarizes maximum observed total concentrations 
in GE's waste, maximum allowable total levels for GE's waste. In all 
cases, the observed levels were below allowable levels.

                                                     Table 3
----------------------------------------------------------------------------------------------------------------
                                        Maximum observed total concentration  (mg/kg)                Maximum
                             ------------------------------------------------------------------ allowable  total
                                                                                                  concentration
                               Sludge drying  beds    Sludge SI  basins    Soil around  basins        mg/kg
----------------------------------------------------------------------------------------------------------------
Arsenic.....................  17.4J                 27.4                  91.0                             91000
Barium......................  21.1                  38.6                  140                           20600000
Cadmium.....................  ND                    1.2                   3.0                             771000

[[Page 13007]]

 
Chromium....................  5360                  8400                  4370                        2310000000
Lead........................  R                     677J                  15.5/94.3J                      541000
Mercury.....................  1.1J                  1.6                   0.49                                80
Nickel......................  10.8/43.3J            43.5/94J              64.4J                         30800000
Selenium....................  0.30J                 0.66                  0.55/0.61J                     7710000
Silver......................  26.4J                 46.5                  22.1                           7710000
Cyanide.....................  R                     ND                    ND                           30800000
----------------------------------------------------------------------------------------------------------------
Note: ND=Not Detected (Detection Limit).
J=value is an estimated quantity.
R=rejected.

B. What Are the Conditions of the Exclusion?

    The proposed exclusion only applies to the approximately five to 
fifteen thousand cubic yards of sludge and contaminated soil described 
in the petition. Any amount exceeding this volume cannot be considered 
delisted under this exclusion. Furthermore, GE must dispose of this 
sludge in a Subtitle D landfill which is permitted, licensed, or 
registered by a state to manage industrial waste.
    GE must also complete additional verification sampling in order to 
ensure that the landfilled sludge meets delisting requirements. Each 
unit shall at a minimum be divided into four quadrants and a boring 
drilled at the center or an identified area of concern within each 
quadrant. A composite sample comprising the vertical extent of the 
sludge at each individual boring location is to be collected within the 
sludge areas of the two drying beds and the two basins. Surface 
composite samples using the same number of quadrant above shall be 
collected for the sludge in the two basins and the contaminated soil in 
the vicinity of the basins. The 102,400 square foot grid surrounding 
the basins could stake on an 160-foot interval for a square grid area 
of approximately 25,600 square feet (a total of four square grid). A 
soil boring shall be installed at the center of each square grid for a 
total of 4 soil borings. Boring samples shall be collected at three 
depth levels (top, middle and bottom) for a total of three samples at 
each boring location. A total of 40 samples is expected from the drying 
beds, the basins and the area surrounding the basins. QA/QC protocols 
would remain as spelled out in the petition. The samples are to be 
analyzed for TCLP metals that includes arsenic, barium, cadmium, 
chromium and nickel.
    If, anytime after disposal of the delisted waste, GE possesses or 
is otherwise made aware of any environmental or waste data (including 
but not limited to leachate data or groundwater monitoring data) or any 
other data relevant to the delisted waste indicating that any 
constituent identified in section VI.A. is at a level higher than the 
delisting level established in section VI.A. or is at a level in 
groundwater that exceeds the point of exposure concentration 
established in section VI.A., then GE must report such data, in 
writing, to the Director of the Division of Environmental Planning and 
Protection within 10 days of first possessing or being made aware of 
that data.
    Based on any information provided by GE and any other information 
received from any source, the Director of the Division of Environmental 
Planning and Protection will make a determination as to whether the 
reported information requires GE to take action to protect human health 
or the environment. Further action may include suspending, or revoking 
the exclusion, or other appropriate response necessary to protect human 
health and the environment.

C. What Happens if GE Fails To Meet the Conditions of the Exclusion?

    If GE violates the terms and conditions established in the 
exclusion, the Agency may start procedures to withdraw the exclusion.
    The EPA has the authority under RCRA and the Administrative 
Procedures Act, 5 U.S.C. 551 (1978) et seq. (APA), to reopen a 
delisting decision if we receive new information indicating that the 
conditions of this exclusion have been violated.
    If the Director of the Division of Environmental Planning and 
Protection determines that information reported by GE as described in 
section VI.B., or information received from any other source, does 
require GE to take action the Director of the Division of Environmental 
Planning and Protection will notify GE in writing of the actions the 
Director of the Division of Environmental Planning and Protection 
believes are necessary to protect human health and the environment. The 
notice shall include a statement of the proposed action and a statement 
providing GE with an opportunity to present information as to why the 
proposed action is not necessary or to suggest an alternative action. 
GE shall have 10 days from the date of the Director's notice or such 
other time period as established by EPA to present the information.
    If after 10 days, GE presents no further information, the Director 
of the Division of Environmental Planning and Protection will issue a 
final written determination describing the actions that are necessary 
to protect human health or the environment. Any required action 
described in the Director's determination shall become effective 
immediately, unless the Director of the Division of Environmental 
Planning and Protection provides otherwise.

VII. Regulatory Impact

    Under Executive Order 12866, EPA must conduct an ``assessment of 
the potential costs and benefits'' for all ``significant'' regulatory 
actions.
    The proposal to grant an exclusion is not significant, since its 
effect, if promulgated, would be to reduce the overall costs and 
economic impact of EPA's hazardous waste management regulations. This 
reduction would be achieved by excluding waste generated at a specific 
facility from EPA's lists of hazardous wastes, thus enabling a facility 
to manage its waste as nonhazardous.
    Because there is no additional impact from today's proposed rule, 
this

[[Page 13008]]

proposal would not be a significant regulation, and no cost/benefit 
assessment is required. The Office of Management and Budget (OMB) has 
also exempted this rule from the requirement for OMB review under 
section (6) of Executive Order 12866.

VIII. Regulatory Flexibility Act

    Under the Regulatory Flexibility Act, 5 U.S.C. 601-612, whenever an 
agency is required to publish a general notice of rulemaking for any 
proposed or final rule, it must prepare and make available for public 
comment a regulatory flexibility analysis which describes the impact of 
the rule on small entities (that is, small businesses, small 
organizations, and small governmental jurisdictions). No regulatory 
flexibility analysis is required, however, if the Administrator or 
delegated representative certifies that the rule will not have any 
impact on small entities.
    This rule, if promulgated, will not have an adverse economic impact 
on small entities since its effect would be to reduce the overall costs 
of EPA's hazardous waste regulations and would be limited to one 
facility. Accordingly, the Agency certifies that this proposed 
regulation, if promulgated, will not have a significant economic impact 
on a substantial number of small entities. This regulation, therefore, 
does not require a regulatory flexibility analysis.

IX. Paperwork Reduction Act

    Information collection and record-keeping requirements associated 
with this proposed rule have been approved by Office of Management of 
Budget (OMB) under the provisions of the Paperwork Reduction Act of 
1980 (Public Law 96-511, 44 U.S.C. 3501 et seq.) and have been assigned 
OMB Control Number 2050-0053.

X. Unfunded Mandates Reform Act

    Under section 202 of the Unfunded Mandates Reform Act of 1995 
(UMRA), Public Law 104-4, which was signed into law on March 22, 1995, 
EPA generally must prepare a written statement for rules with federal 
mandates that may result in estimated costs to state, local, and tribal 
governments in the aggregate, or to the private sector, of $100 million 
or more in any one year.
    When such a statement is required for EPA rules, under section 205 
of the UMRA, EPA must identify and consider alternatives, including the 
least costly, most cost-effective, or least burdensome alternative that 
achieves the objectives of the rule. EPA must select that alternative, 
unless the Administrator explains in the final rule why it was not 
selected or it is inconsistent with law.
    Before EPA establishes regulatory requirements that may 
significantly or uniquely affect small governments, including tribal 
governments, EPA must develop under section 203 of the UMRA a small 
government agency plan. The plan must provide for notifying potentially 
affected small governments, giving them meaningful and timely input in 
the development of EPA regulatory proposals with significant federal 
intergovernmental mandates, and informing, educating, and advising them 
on compliance with the regulatory requirements.
    The UMRA generally defines a federal mandate for regulatory 
purposes as one that imposes an enforceable duty upon state, local, 
tribal governments or the private sector estimated to cost $100 million 
or more in any one year.
    The EPA finds that today's delisting decision is deregulatory in 
nature and does not impose any enforceable duty on any state, local, or 
tribal governments or the private sector estimated to cost $100 million 
or more in any one year. In addition, the proposed delisting decision 
does not establish any regulatory requirements for small governments 
and so does not require a small government agency plan under UMRA 
section 203.

XI. Executive Order 12875

    Under Executive Order 12875, EPA may not issue a regulation that is 
not required by statute and that creates a mandate upon a state, local, 
or tribal government, unless the federal government provides the funds 
necessary to pay the direct compliance costs incurred by those 
governments. If the mandate is unfunded, EPA must provide to OMB a 
description of the extent of EPA's prior consultation with 
representatives of affected state, local, and tribal governments; the 
nature of their concerns; copies of written communications from the 
governments; and a statement supporting the need to issue the 
regulation. In addition, Executive Order 12875 requires EPA to develop 
an effective process permitting elected officials and other 
representatives of state, local, and tribal governments ``to provide 
meaningful and timely input in the development of regulatory proposals 
containing significant unfunded mandates.'' Today's rule does not 
create a mandate on state, local or tribal governments. The rule does 
not impose any enforceable duties on these entities. Accordingly, the 
requirements of section 1(a) of Executive Order 12875 do not apply to 
this rule.

XII. Executive Order 13045

    Executive Order 13045 is entitled ``Protection of Children from 
Environmental Health Risks and Safety Risks'' (62 FR 19885, April 23, 
1997). This order applies to any rule that EPA determines (1) is 
economically significant as defined under Executive Order 12866, and 
(2) the environmental health or safety risk addressed by the rule has a 
disproportionate effect on children. If the regulatory action meets 
both criteria, the Agency 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 the Agency. This 
proposed rule is not subject to Executive Order 13045 because this is 
not an economically significant regulatory action as defined by 
Executive Order 12866.

XIII. Executive Order 13084

    Under Executive Order 13084, EPA may not issue a regulation that is 
not required by statute, that significantly affects or uniquely affects 
that communities of Indian tribal governments, and that imposes 
substantial direct compliance costs on those communities, unless the 
Federal government provides the funds necessary to pay the direct 
compliance costs incurred by the tribal governments.
    If the mandate is unfunded, EPA must provide to OMB, in a 
separately identified section of the preamble to the rule, a 
description of the extent of EPA's prior consultation with 
representatives of affected tribal governments, a summary of the nature 
of their concerns, and a statement supporting the need to issue the 
regulation.
    In addition, Executive Order 13084 requires EPA to develop an 
effective process permitting elected and other representatives of 
Indian tribal governments ``to meaningful and timely input'' in the 
development of regulatory policies on matters that significantly or 
uniquely affect their communities of Indian tribal governments. This 
action does not involve or impose any requirements that affect Indian 
Tribes. Accordingly, the requirements of section 3(b) of Executive 
Order 13084 do not apply to this rule.

XIV. Executive Order 13132

    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

[[Page 13009]]

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 levels of government.''
    Under section 6 of Executive Order 13132, EPA may not issue a 
regulation that has federalism implications, that imposes substantial 
direct compliance costs, and that is not required by statute, unless 
the Federal government provides the funds necessary to pay the direct 
compliance costs incurred by State and local governments or EPA 
consults with State and local officials early in the process of 
developing the proposed regulation. EPA also may not issue a regulation 
that has federalism implication and that preempts State law, unless the 
Agency consults with State and local officials early in the process of 
developing the proposed regulation.
    This proposed 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 the Executive Order 13132. Thus, the requirements of 
section 6 of the Executive Order do not apply to this rule.

XV. National Technology Transfer and Advancement Act

    Under section 12(d) of the National Technology Transfer and 
Advancement Act, the Agency is directed to use voluntary consensus 
standards in its regulatory activities unless doing so would be 
inconsistent with applicable law or otherwise impractical.
    Voluntary consensus standards are technical standards (for example, 
materials specifications, test methods, sampling procedures, business 
practices, etc.) that are developed or adopted by voluntary consensus 
standard bodies. Where EPA does not use available and potentially 
applicable voluntary consensus standards, the Act requires that Agency 
to provide Congress, through the OMB, an explanation of the reasons for 
not using such standards.
    This rule does not establish any new technical standards, and thus 
the Agency has no need to consider the use of voluntary consensus 
standards in developing this proposed rule.

List of Subjects in 40 CFR Part 261

    Environmental protection, Hazardous waste, Recycling, Reporting and 
recordkeeping requirements.

    Authority: Sec. 3001(f) RCRA, 42 U.S.C. 6921(f).

    Dated: December 15, 2003.
Walter Mugdan,
Director, Division of Environmental Planning and Protection.

    Editorial Note: This document was received in the Office of the 
Federal Register on March 16, 2004.

    For the reasons set out in the preamble, 40 CFR part 261 is 
proposed to be 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, and 6938.

    2. In Table 1 of appendix IX of part 261, add the following waste 
stream in alphabetical order by facility to read as follows:

Appendix IX to Part 261--Wastes Excluded Under Sec. Sec.  260.20 and 
260.22

                               Table 1.--Wastes Excluded From Non-Specific Sources
----------------------------------------------------------------------------------------------------------------
                  Facility                                     Address                       Waste description
----------------------------------------------------------------------------------------------------------------
 
                                                  * * * * * * *
GE's Former RCA del Caribe.................  Barceloneta Puerto Rico....................  Wastewater treatment
                                                                                           plant (WWTP) sludges
                                                                                           from chemical etching
                                                                                           operation. (EPA
                                                                                           Hazardous Waste No.
                                                                                           F006) and
                                                                                           contaminated soil
                                                                                           mixed with sludge.
                                                                                           This is a one-time
                                                                                           exclusion for a range
                                                                                           of 5,000 to15,000
                                                                                           cubic yards of WWTP
                                                                                           sludge. This
                                                                                           exclusion was
                                                                                           published on [insert
                                                                                           publication date of
                                                                                           the final rule].
                                                                                          1. Delisting Levels:
                                                                                          (A) The constituent
                                                                                           concentrations
                                                                                           measured in the TCLP
                                                                                           extract may not
                                                                                           exceed the following
                                                                                           levels (mg/L):
                                                                                           arsenic--0.0604;
                                                                                           barium--472; cadmium--
                                                                                           3.63; chromium--
                                                                                           1,400,000; lead--484;
                                                                                           mercury--0.219;
                                                                                           nickel--182;
                                                                                           selenium--14; silver--
                                                                                           24.8; and cyanide--
                                                                                           87.1
                                                                                          (B) The total
                                                                                           constituent
                                                                                           concentrations in any
                                                                                           sample may not exceed
                                                                                           the following levels
                                                                                           (mg/kg): arsenic--
                                                                                           91,000; barium--
                                                                                           20,600,000; cadmium--
                                                                                           771,000; chromium--
                                                                                           2,310,000,000; lead--
                                                                                           541,000; mercury--80;
                                                                                           nickel--30,800,000;
                                                                                           selenium--771,000;
                                                                                           silver--771,000; and
                                                                                           cyanide--30,800,000.

[[Page 13010]]

 
                                                                                          2. Verification
                                                                                           Sampling--For the two
                                                                                           drying beds and two
                                                                                           basins, composite
                                                                                           samples comprising
                                                                                           the vertical extent
                                                                                           at individual boring
                                                                                           location; for the
                                                                                           contaminated soil
                                                                                           around the basins;
                                                                                           boring samples at 3
                                                                                           different depth
                                                                                           levels (top, middle
                                                                                           and bottom) also at
                                                                                           individual boring
                                                                                           location, are to be
                                                                                           collected from four
                                                                                           different boring
                                                                                           locations or quadrant
                                                                                           within each of the
                                                                                           units and four
                                                                                           different square grid
                                                                                           areas within the soil
                                                                                           surrounding the
                                                                                           basins. Surface
                                                                                           composite samples
                                                                                           within each quadrant
                                                                                           and square grid shall
                                                                                           also be collected for
                                                                                           the sludge in the two
                                                                                           basins and the
                                                                                           contaminated soil in
                                                                                           the vicinity of the
                                                                                           basins. A total of
                                                                                           forty samples must be
                                                                                           collected as follows:
                                                                                           Sixteen boring
                                                                                           composite samples for
                                                                                           the drying beds and
                                                                                           basins, twelve
                                                                                           surface composite
                                                                                           samples for the
                                                                                           basins and
                                                                                           contaminated soil,
                                                                                           and twelve boring
                                                                                           samples for the soil
                                                                                           around the basins.
                                                                                           The samples are to be
                                                                                           analyzed for TCLP
                                                                                           metals that include
                                                                                           arsenic, barium,
                                                                                           cadmium, chromium and
                                                                                           nickel. The results
                                                                                           are to be compared to
                                                                                           the delisting levels
                                                                                           in Condition (1)(a).
                                                                                           Sludge from which
                                                                                           samples collected
                                                                                           exceed delisting
                                                                                           levels are not
                                                                                           delisted. Additional
                                                                                           sampling can be
                                                                                           conducted with the
                                                                                           approval of U.S. EPA
                                                                                           Region 2 in order to
                                                                                           isolate the sludge
                                                                                           which exceeds the
                                                                                           delisting levels from
                                                                                           sludge that meets the
                                                                                           delisting levels.
                                                                                          3. Reopener Language--
                                                                                           (a) If, anytime after
                                                                                           disposal of the
                                                                                           delisted waste, GE
                                                                                           possesses or is
                                                                                           otherwise made aware
                                                                                           of any data
                                                                                           (including but not
                                                                                           limited to leachate
                                                                                           data or groundwater
                                                                                           monitoring data) or
                                                                                           any other data
                                                                                           relevant to the
                                                                                           delisted waste
                                                                                           indicating that any
                                                                                           constituent
                                                                                           identified in
                                                                                           Condition (1) is at a
                                                                                           level higher than the
                                                                                           delisting level
                                                                                           established in
                                                                                           Condition (1), or is
                                                                                           at a level in the
                                                                                           groundwater at a
                                                                                           level exceeding the
                                                                                           point of exposure
                                                                                           groundwater levels
                                                                                           established in
                                                                                           section VI.A. of the
                                                                                           preamble, then GE
                                                                                           must report such
                                                                                           data, in writing, to
                                                                                           the Director of the
                                                                                           Division of
                                                                                           Environmental
                                                                                           Planning and
                                                                                           Protection within 10
                                                                                           days of first
                                                                                           possessing or being
                                                                                           made aware of that
                                                                                           data. (b) Based on
                                                                                           the information
                                                                                           described in
                                                                                           paragraph (a) and any
                                                                                           other information
                                                                                           received from any
                                                                                           source, the Director
                                                                                           will make a
                                                                                           preliminary
                                                                                           determination as to
                                                                                           whether the reported
                                                                                           information requires
                                                                                           GE to take action to
                                                                                           protect human health
                                                                                           or the environment.
                                                                                           Further action may
                                                                                           include suspending,
                                                                                           or revoking the
                                                                                           exclusion, or other
                                                                                           appropriate response
                                                                                           necessary to protect
                                                                                           human health and the
                                                                                           environment.
                                                                                          (c) If the Director of
                                                                                           the Division of
                                                                                           Environmental
                                                                                           Planning and
                                                                                           Protection determines
                                                                                           that the reported
                                                                                           information does
                                                                                           require action, the
                                                                                           Director of the
                                                                                           Division of
                                                                                           Environmental
                                                                                           Planning and
                                                                                           Protection will
                                                                                           notify GE in writing
                                                                                           of the actions the
                                                                                           Director believes are
                                                                                           necessary to protect
                                                                                           human health and the
                                                                                           environment. The
                                                                                           notice shall include
                                                                                           a statement of the
                                                                                           proposed action and a
                                                                                           statement providing
                                                                                           GE with an
                                                                                           opportunity to
                                                                                           present information
                                                                                           as to why the
                                                                                           proposed action is
                                                                                           not necessary or to
                                                                                           suggest an
                                                                                           alternative action.
                                                                                           GE shall have 10 days
                                                                                           from the date of the
                                                                                           Director's notice or
                                                                                           such other time
                                                                                           period as is
                                                                                           established by EPA to
                                                                                           present the
                                                                                           information.
                                                                                          (d) If after 10 days
                                                                                           GE presents no
                                                                                           further information,
                                                                                           the Director of the
                                                                                           Division of
                                                                                           Environmental
                                                                                           Planning and
                                                                                           Protection will issue
                                                                                           a final written
                                                                                           determination
                                                                                           describing the
                                                                                           actions that are
                                                                                           necessary to protect
                                                                                           human health or the
                                                                                           environment. Any
                                                                                           required action
                                                                                           described in the
                                                                                           Director's
                                                                                           determination shall
                                                                                           become effective
                                                                                           immediately, unless
                                                                                           the Director of the
                                                                                           Division of
                                                                                           Environmental
                                                                                           Planning and
                                                                                           Protection provides
                                                                                           otherwise.
                                                                                          4. Notifications--GE
                                                                                           must provide a one-
                                                                                           time written
                                                                                           notification to any
                                                                                           State Regulatory
                                                                                           Agency to which or
                                                                                           through which the
                                                                                           waste described above
                                                                                           will be transported
                                                                                           for disposal at least
                                                                                           60 days prior to the
                                                                                           commencement of such
                                                                                           activities. Failure
                                                                                           to provide such a
                                                                                           notification will
                                                                                           result in a violation
                                                                                           of the waste
                                                                                           exclusion and a
                                                                                           possible revocation
                                                                                           of the decision.
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[FR Doc. 04-6216 Filed 3-18-04; 8:45 am]
BILLING CODE 6560-50-P