[Federal Register Volume 60, Number 23 (Friday, February 3, 1995)]
[Rules and Regulations]
[Pages 6666-6670]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 95-2627]



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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 270

[FRL-5149-1]


Determination of Point at Which RCRA Subtitle C Jurisdiction 
Begins for Municipal Waste Combustion Ash at Waste-to-Energy Facilities

AGENCY: Environmental Protection Agency (EPA).

ACTION: Notice of statutory interpretation.

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SUMMARY: On May 2, 1994, the Supreme Court issued its decision in City 
of Chicago v. Environmental Defense Fund, Inc. 114 S.Ct. 1588 (1994). 
In so doing, the Court held that, although municipal waste-to-energy 
(WTE) facilities that burn household wastes alone, or in combination 
with nonhazardous wastes from industrial and commercial sources, are 
exempt from regulation as a hazardous waste treatment, storage, or 
disposal facility under Subtitle C of the Resource Conservation and 
Recovery Act (RCRA), the ash that they generate is not exempt. The 
Court, however, did not specify the point at which the ash generated by 
the WTE facility becomes subject to Subtitle C of RCRA. EPA is 
responding to numerous requests for resolution of this issue by 
announcing today that it interprets Sec. 3001(i) of RCRA to first 
subject the ash generated by a WTE facility to RCRA Subtitle C when it 
exits the combustion building following the combustion and air 
pollution control processes.

EFFECTIVE DATE: February 3, 1995.

ADDRESSES: Docket Clerk, OSW (OS-305), Docket No. 95-XA2N-FFFFF, U.S. 
Environmental Protection Agency Headquarters, 401 M Street, SW., 
Washington, DC 20460. The public docket is located in M2616 at EPA 
Headquarters and is available for viewing from 9:00 a.m. to 4:00 p.m., 
Monday through Friday, excluding Federal holidays. Appointments may be 
made by calling (202) 260-9327. Copies cost $0.15/page. Charges under 
$25.00 are waived.

FOR FURTHER INFORMATION CONTACT:
For general information, contact the RCRA/Superfund Hotline, Office of 
Solid Waste, U.S. Environmental Protection Agency, 401 M Street, SW., 
Washington, DC, 20460, (800) 424-9346, TDD (800) 553-7672 (hearing 
impaired); in the Washington, DC metropolitan area the number is (703) 
920-9810, TDD (703) 486-3323.
    For more detailed information on specific aspects of this Notice, 
contact Andrew L. Teplitzky (703-308-7275) or Allen J. Geswein (703-
308-7261), Office of Solid Waste (5306W), U.S. Environmental Protection 
Agency, 401 M Street, SW., Washington, DC 20460.

SUPPLEMENTARY INFORMATION:

Preamble Outline

I. Authority
II. Background
    A. Nature of Ash From Waste-To-Energy Facilities
    B. Regulatory History of Waste-to-Energy Ash
    C. Initial Agency Reaction to the Supreme Court Decision
III. The Point of Subtitle C Jurisdiction
    A. EPA's Interpretation
    1. Legal Analysis
    2. Illustrative Examples
    B. Other Interpretations Considered
    1. Facility Property Boundary
    2. Inside the Combustion Building
    C. Additional Policy Considerations
IV. Conclusion

I. Authority

    This action interpreting RCRA Section 3001(i) and the hazardous 
waste regulations in 40 CFR Parts 260-271 is being taken under the 
authority of sections 2002 and 3001 of the Solid Waste Disposal Act of 
1970 as amended by the Resource Conservation and Recovery Act of 1976, 
as amended (42 U.S.C. 6912 and 6921).

II. Background

A. Nature of Ash From Waste-to-Energy Facilities

    Combustion of municipal solid waste, particularly through WTE 
facilities, can be an important component of a local government's waste 
management practices. As of 1993, approximately 207 million tons of 
municipal solid waste were generated annually in the U.S., 16 percent 
of which (33 million tons) was combusted. There are approximately 150 
municipal waste combustors in the U.S., 80 percent of which are WTE 
facilities. The remaining 20 percent incinerate waste without 
recovering energy.
    Approximately 25 percent (dry weight) of the waste that is 
combusted remains as ash, amounting to around eight million tons of 
municipal waste combustor (MWC) ash generated annually. While the ash 
may be collected at a number of locations within a WTE facility, it 
typically is characterized as either ``bottom ash'' or ``fly ash.'' 
Bottom ash collects at the bottom of the combustion unit and comprises 
approximately 75-80% of the total ash by weight. Fly ash collects in 
the air pollution control devices that ``clean'' the gases produced 
during the combustion of the waste and comprises [[Page 6667]] around 
20-25% of the total by weight. The fly ash from a WTE facility's 
different air pollution control devices typically is consolidated and 
then combined with the bottom ash via enclosed conveyors at the bottom 
of the MWC where it is cooled and conveyed to a storage area. EPA 
estimates that nearly 80% of WTE facilities routinely combine their 
ash.
    The regulation of WTE ash has been the subject of controversy and 
debate ever since the inception of the hazardous waste management 
program under Subtitle C of RCRA. EPA's notice of June 7, 1994 (59 Fed. 
Reg. 29372) provides a discussion of the regulatory history of ash from 
WTE facilities. The following section summarizes that discussion.

B. Regulatory History of Waste-to-Energy Ash

    In 1980, EPA promulgated a rule exempting household wastes from all 
RCRA requirements for hazardous wastes (40 CFR 261.4(b)(1)). EPA 
interpreted this exemption to extend to the residuals from the 
treatment of household wastes, including ash from the combustion of 
household wastes. The exemption, however, did not address ash from the 
combustion of household wastes combined with nonhazardous commercial 
and industrial wastes.
    In 1984, Congress added to RCRA a new Section 3001(i). This 
provision addressed WTE facilities burning exempt household hazardous 
wastes and nonhazardous commercial and industrial wastes to produce 
energy. In July 1985, EPA promulgated a rule that codified this 
provision. In the preamble accompanying this rule, EPA announced that 
it interpreted the statute to exempt the combustion of waste, but not 
the management of ash, from Subtitle C (50 Fed. Reg. 28702, 28725-26 
(July 15, 1985)). Since 1985, the Agency's interpretation of 
Sec. 3001(i) of RCRA has been a subject of much debate.
    In September 1992, EPA Administrator William Reilly signed a 
memorandum announcing that the Agency interpreted Section 3001(i) to 
exempt from all Subtitle C requirements ash from WTE facilities burning 
household wastes and nonhazardous wastes. On May 2, 1994, the Supreme 
Court issued an opinion interpreting Section 3001(i) of RCRA, 42 U.S.C. 
6921(i). City of Chicago v. EDF, 114 S.Ct. 1588 (1994). The Court held 
that this provision does not exempt ash generated at WTE facilities 
burning household wastes and nonhazardous commercial wastes from the 
hazardous waste requirements of Subtitle C of RCRA.
    As a result of this decision, persons generating ash from WTE 
facilities must determine whether the ash is hazardous. Studies show 
that ash sometimes is a hazardous waste under RCRA because it exhibits 
EPA's toxicity characteristic (TC). Generally, this determination is 
made by either testing using the Toxicity Characteristic Leaching 
Procedure (TCLP) (see 40 CFR Sec. 261.24) or by using knowledge of the 
combustion process to determine whether the ash would exhibit the TC. 
Typically, ash that ``fails'' the TC leaches lead or cadmium above 
levels of concern. Existing studies also show that fly ash contains the 
highest concentrations of inorganic chemical constituents. It is more 
likely to exhibit the TC than either bottom ash or combinations of 
bottom ash and fly ash. Ash that is determined to be a hazardous waste 
must be handled in compliance with EPA regulations for hazardous waste 
management. Ash that is determined not to be a hazardous waste may be 
disposed in a non-hazardous waste facility.

C. Initial Agency Reaction to the Supreme Court Decision

    While the Supreme Court decision ended nearly a decade of 
controversy over the general regulatory status of ash, it also raised 
some new legal and policy issues. To provide some immediate interim 
guidance, the Agency issued several documents shortly after the Supreme 
Court decision.
    First, on May 24, 1994, the Agency released for immediate use a 
draft guidance manual for ``Sampling and Analysis of Municipal Refuse 
Incinerator Ash.'' The purpose of the manual was to assist owners and 
operators of MWCs in designing a plan for testing ash to determine 
whether it is hazardous. On June 23, 1994, EPA formally requested 
public comment on the draft guidance (59 Fed. Reg. 32427). The comment 
period ended on September 21, 1994. The Agency intends to issue a final 
guidance manual in the Spring of 1995.
    Second, on May 27, 1994, EPA issued a memorandum outlining an 
implementation strategy to assist affected parties in achieving 
compliance with the Court's decision. The strategy identified the 
Agency's priorities for pursuing enforcement actions concerning the 
management of MWC ash. The Agency intends to issue a revised 
implementation strategy shortly.
    Third, on June 7, 1994, the Agency published a notice addressing 
two issues of statutory and regulatory interpretation related to the 
management of WTE ash that is hazardous (59 Fed. Reg. 29372). First, 
the notice extended the deadline within which owners/operators of 
facilities that treat, store, or dispose of hazardous ash must file a 
hazardous waste permit application. This action gave owners and 
operators of facilities that manage hazardous ash six months to apply 
for ``interim status'' under the RCRA hazardous waste regulatory 
program. Without interim status, the facility would be out of 
compliance with RCRA's permit requirements and face potentially 
significant civil and criminal penalties.
    The second issue discussed in this notice was the Agency's 
interpretation that ash from WTE facilities be classified as a ``newly 
identified waste'' for the purposes of the RCRA land disposal 
restrictions (LDRs), meaning that the current land disposal 
restrictions do not apply. When the restrictions apply, hazardous ash 
will have to meet specified treatment standards prior to land disposal. 
EPA currently takes the position that if a waste exhibits a hazardous 
waste characteristic at its point of generation, it must meet LDR 
standards even if it ceases to exhibit the characteristic prior to land 
disposal.

III. The Point of Subtitle C Jurisdiction

A. EPA's Interpretation

1. Legal Analysis
    Neither the Supreme Court's decision on ash nor any of EPA's 
previous policy statements on ash address the point at which the ash 
generated by a WTE facility becomes subject to Subtitle C of RCRA--in 
other words, at which point or points in the facility the owner/
operator must determine whether the ash exhibits the toxicity 
characteristic of a hazardous waste (and, in the future, the point at 
which LDR restrictions will begin to apply).
    Section 3001(i) provides that ``[a] resource recovery facility 
recovering energy from the mass burning of municipal solid waste shall 
not be deemed to be treating, storing, disposing of, or otherwise 
managing hazardous waste * * *.'' if certain conditions regarding waste 
receipt are met. In the City of Chicago case, the Supreme Court issued 
a narrowly focused opinion addressing the issue of whether this 
language created an exemption for ash generated by resource recovery 
facilities. Noting that the provision fails to mention ash and fails to 
include ``generation'' in the list of exempted activities, the Court 
found that no exemption for ash was intended. 114 S. [[Page 6668]] Ct. 
at 1591-92. In fact, the Court found the statute to be so free from 
ambiguity on this issue that there was no need to consult legislative 
history and no occasion to defer, under the principles of Chevron, 
U.S.A. v. NRDC, 467 U.S. 837 (1984), to the interpretation preferred by 
the Agency. Id. at 1594.
    The Court, however, failed to reach the issue of the precise point 
at which regulation of ash must begin, and section 3001(i) does not 
expressly address the issue. For the reasons set out below, EPA 
believes it is reasonable to interpret Section 3001(i) to first impose 
hazardous waste regulation at the point that the ash leaves the 
``resource recovery facility,'' defined as the combustion building 
(including connected air pollution equipment). Consequently, the point 
at which an ash hazardous waste determination should be made (and, in 
the future, at which the LDRs will begin to apply) is the point at 
which ash exits the combustion building following the combustion and 
air pollution control processes.
    Section 3001(i) does not define the term ``resource recovery 
facility.'' EPA believes that it is reasonable to conclude that 
Congress intended to refer to the building that houses the combustion 
device. This is the common sense reading of the term, and it strikes a 
better balance between the objectives of section 3001(i) and the rest 
of Subtitle C than either of the alternative readings described below. 
Further, EPA believes that it is reasonable to conclude that Congress 
intended to exempt all handling of any hazardous waste within the 
building, including the handling of hazardous ash. Subjecting ash 
within the building to hazardous waste regulation could, for example, 
require operators to collect samples of ash for waste determination 
purposes. It also could affect the number of hazardous ash waste 
streams that would become subject to LDR treatment standards. 
``Collection'' and ``treatment'' are among the activities included in 
the definition of ``management'' in section 1004(7) of RCRA. Section 
3001(i) expressly exempts treatment, storage, disposal and management 
of hazardous waste at resource recovery facilities. See City of 
Chicago, 114 S. Ct. at 1592.
    This interpretation is not only a reasonable reading of the 
statutory language, it also serves Congress' intent to ``encourage 
commercially viable resource recovery facilities and to remove 
impediments to their operation.'' (Emphasis added.) S. Rep. 98-284, 
98th Cong., 2d Sess. at 61. Regulating ash only at the point it exits 
the combustion building removes some potentially significant 
impediments. If the statute allowed regulation of ash inside the 
building, the facility owner/operator might need to sample and analyze 
ash at multiple points. This approach could require owners and 
operators to deal with major logistical problems associated with 
shutting down individual boilers and retrofitting/reconfiguring the 
combustor to accommodate installation of multiple handling and storage 
systems to separately convey the ash streams to different load out 
areas and ash conditioning systems. Some facilities may not currently 
have the space to accommodate the additional equipment required and 
could be forced to either close or temporarily shut down until 
additional space could be procured. Retrofitting a facility in this 
manner could be costly. Some state and industry representatives, in 
fact, have projected costs in excess of several million dollars per 
facility. Hence, this interpretation could conflict with Congressional 
intent by serving as an ``impediment'' to resource recovery facilities. 
S. Rep. 98-284 at 61. In addition, the cost of sampling and analysis 
alone probably would at least double considering collection and 
analysis of at least two different ash streams--bottom ash and fly 
ash--instead of a single combined ash stream. (Although owners and 
operators may legally use knowledge in lieu of testing, due to the 
variable nature of ash, virtually all owners and operators conduct TCLP 
testing.) These costs would contribute to the total burden imposed on 
the WTE facility.
    Finally, in selecting an interpretation of section 3001(i), EPA 
also must consider Subtitle C's general goal of protecting human health 
and the environment from the threats posed by hazardous waste. As 
explained in greater detail in section C below, EPA does not believe 
that this interpretation would have any significant impact on the level 
of environmental protection for ash.
    EPA also believes that today's interpretation is consistent with 
the Supreme Court's 1994 decision construing RCRA Sec. 3001(i). In City 
of Chicago v. EDF, 114 S. Ct. 1588 (1994), the Court held that Congress 
intended to exempt ``resource recovery facilities,'' but did not define 
the term. See, e.g., 114 S. Ct. at 1591-92. While the Court clearly 
stated that the statute did not exempt facility owners from regulation 
as hazardous waste generators, id. at 1592, determining that ash is not 
subject to regulation until it exits the combustion building does not 
exempt the facility owner from regulation as a generator. Rather, it 
defines the point at which the owner must begin to perform the 
generator's duties. Further, today's interpretation does not create the 
type of total exemption for ash that the Supreme Court rejected in City 
of Chicago. Operators of MWC facilities still must comply with the 
generator's duty to make a hazardous waste determination. Any ash that 
exhibits a characteristic when exiting the combustion building must be 
managed in compliance with all applicable Subtitle C requirements. 
EPA's interpretation merely clarifies the location at which the 
determination for waste characterization purposes must occur (and the 
point at which future LDRs requirements will begin to apply).
2. Illustrative Examples
    Today's interpretation is perhaps best explained through the use of 
specific examples. For instance, many WTE facilities automatically 
convey, via enclosed conveyor, the fly ash collected at its various 
locations (including any air pollution control devices such as the acid 
gas scrubbers, baghouse filters, and electrostatic precipitators that 
may exist outside the combustion building) to a quench tank within the 
combustion building where it is combined with the bottom ash. The 
combined ash is then conveyed to a separate, detached storage building 
or to trucks for direct transport to an off-site disposal facility. The 
point at which RCRA hazardous waste jurisdiction would begin for these 
facilities would be the point where the ash exits the combustion 
building. Under this interpretation, the owner/operator could combine 
fly ash and bottom ash within the combustion building before making any 
hazardous waste determination. Any type of device could be used within 
the building for ash management activities such as collection, mixing, 
and conditioning.
    EPA includes in its interpretation of ``resource recovery 
facility'' those air pollution control devices that are integral 
components of the combustion process. Ash from air pollution control 
devices that is reconveyed back to the combustion building in enclosed 
ducts has, in EPA's view, not left the ``resource recovery facility'' 
exempted under Sec. 3001(i). Moreover, the ducts and air pollution 
control devices contain the ash so it does not come into contact with 
the environment.
    A few WTE facilities may exist where the combustion device is not 
housed within a building. In these instances, the combustion device 
(including air pollution control equipment and proximate areas for 
handling ash) may constructively constitute a combustion building, 
within the meaning discussed above. Thus, if fly ash and bottom ash 
[[Page 6669]] were handled in enclosed systems that operate in the same 
manner as they would if a building existed and the fly ash and bottom 
ash were mixed in an enclosed unit proximate to the combustion device, 
that management activity would be considered to take place within a 
combustion building as described above. In this circumstance, the point 
at which hazardous waste jurisdiction would begin would be the point 
where the combined ash exits the last enclosed ash management unit that 
is located proximate to the combustion device.
    By contrast, where a WTE facility collects bottom ash within the 
combustion building and collects the fly ash outside the combustion 
building in, for example, roll-off containers, two distinct exit points 
from the combustion building exist: (1) the point where the bottom ash 
ultimately leaves the combustion building and (2) the point where the 
fly ash leaves the air pollution control devices (located outside the 
combustion building). The WTE facility operator would thus sample and 
make a hazardous waste determination at each location. Should the 
operator determine that either the bottom ash or fly ash as is 
hazardous, management of that ash would have to be conducted pursuant 
to RCRA Subtitle C.

B. Other Interpretations Considered

    Since the Supreme Court decision, the Agency has received numerous 
letters from states, local governments, industry, environmental groups, 
and others suggesting various approaches to determining the point at 
which the ash initially becomes subject to RCRA Subtitle C 
jurisdiction. For example, a number of comments received in response to 
the Agency's draft sampling and analysis guidance notice of May 24, 
1994, addressed this issue. Some members of the public urged EPA to 
adopt the interpretation described above. Other members, however, 
suggested two additional options for interpreting Sec. 3001(i) to 
establish the point at which ash becomes subject to Subtitle C 
regulation.
1. Facility Property Boundary
    Some members of the public argued that the hazardous waste 
exclusion under RCRA Sec. 3001(i) applies to all ash management 
operations within the property boundary of the WTE facility. This 
interpretation potentially would allow all ash generated at a WTE 
facility to be managed on-site, without testing, as a non-hazardous 
waste. It could allow a WTE facility to dispose of ash that would have 
otherwise failed the TCLP within the facility property boundary in a 
landfill that does not meet the requirements of RCRA Subtitle C.
    EPA is rejecting the option of designating the point of Subtitle C 
jurisdiction at the property boundary. The most natural reading of the 
term ``resource recovery facility'' is the combustion device itself. 
Nothing in the text of the statute or the legislative history refers to 
land holdings or suggests that Congress was familiar with them and the 
types of waste management conducted on them. Rather, the discussion 
focuses on the combustion process. EPA believes that an exemption for 
the entire property would conflict with the general goals of Subtitle C 
because it would provide too many opportunities for potential 
mismanagement of ash at the WTE facility without the proper 
environmental controls. Such a broad reading of RCRA could allow 
potential mismanagement of ash that tested hazardous within the land 
boundaries of the facility in units (e.g., waste piles, landfills) that 
were not appropriately regulated under Subtitle C of RCRA. EPA believes 
that this option would not strike the balance that Congress intended 
between section 3001(i)'s goal of promoting resource recovery 
facilities and the general environmental protection goals of the rest 
of RCRA Subtitle C.
2. Inside the Combustion Building
    Other members of the public argued that the exemption in section 
3001(i) ends at the instant that ash is generated. In particular, they 
objected to any temporary exemption for ash that would allow facility 
owners to combine fly ash and bottom ash before making hazardous waste 
determinations. Since combined ash tends to ``pass'' the TC, postponing 
regulation until combination has occurred could allow the ash to escape 
Subtitle C management. These commentors argued that such a ``de facto'' 
exemption for WTE ash would be inconsistent with the spirit of the 
Supreme Court's decision in City of Chicago.
    EPA has decided not to read the statute to require regulation of 
ash within the combustion building. This interpretation would permit 
regulation of the management of hazardous ash within the ``resource 
recovery facility,'' in apparent contradiction with the text of section 
3001(i). Further, requiring sampling, testing, and management of ash 
from multiple locations could, as described below, be unnecessarily 
expensive and burdensome in relation to the environmental benefits 
received. Thus, this interpretation could conflict with Congress' goal 
of ``promoting resource recovery facilities.'' S. Rep. 98-284, 98th 
Cong. at 61.
    Many of the people advocating this interpretation maintained that 
this interpretation would require bottom ash and fly ash to be sampled 
separately, before a facility owner combines them. Ash, however, may 
collect in as many as 20 separate locations within an average WTE 
facility. This interpretation, if applied literally to the first 
locations where ash becomes identifiable, could lead to a policy 
requiring that a waste determination be made at each of these 
locations. Such a policy would only increase the impediments to viable 
resource recovery facilities.

C. Additional Policy Considerations

    EPA believes that today's interpretation of Sec. 3001(i) 
designating the point of Subtitle C jurisdiction at the exit of the 
combustion building provides an approach that local governments will 
find practical and implementable, yet environmentally protective. In 
accordance with today's interpretation, ash that is combined (and 
conditioned, for example, with lime and/or phosphoric acid) at the end 
of the combustion process and within the combustion building, and 
exhibits no hazardous waste characteristics (i.e., it passes the TCLP) 
when it exits that building, may be sent to a nonhazardous waste 
facility for disposal.
    In comparison, if the Agency had selected the option requiring 
hazardous waste determinations inside the combustion building, the fly 
ash and bottom ash that would have been tested separately at locations 
inside the combustion building and found to exhibit the toxicity 
characteristic would not be handled much differently. The WTE facility 
operator could treat (using similar conditioning techniques that are 
performed inside the combustion building under today's interpretation) 
the fly ash and bottom ash in on-site tanks, containers, or containment 
buildings under the provisions of Sec. 262.34. Such treatment does not 
require a federal hazardous waste (Subtitle C) permit so long as the 
ash is not retained for more than 90 days. Once the ash ceased to 
exhibit hazardous waste toxicity characteristics, it too would be 
combined and sent for disposal in a nonhazardous waste facility. 
Similarly, once the LDR treatment standards for WTE ash hazardous 
constituents are promulgated, the ash would be treated (perhaps using 
some of the same conditioning techniques used today) to meet those 
standards at which point the ash could [[Page 6670]] then be sent for 
disposal in a nonhazardous waste facility.
    EPA also believes that current regulations promulgated under RCRA 
Subtitle D provide protection for the disposal of ash as a nonhazardous 
waste. In 1991, the Agency promulgated new criteria for municipal solid 
waste landfills, including landfills and monofills that accept MWC ash 
(40 CFR Part 258). These criteria impose a comprehensive set of 
requirements on municipal solid waste landfills (MSWLFs) including 
requirements for location restrictions, facility design and operation, 
ground-water monitoring and corrective action, closure and post-closure 
care, and financial assurance. The Agency has conducted studies on the 
land disposal of MWC ash from WTE facilities and has found no evidence 
to suggest that disposal in a Subtitle D landfill will endanger human 
health and the environment. Copies of these studies are available in 
the docket for this notice.
    For example, EPA has conducted a study on the effects of MWC ash 
leachate on natural and synthetic lining materials commonly employed in 
the construction of municipal solid waste landfill liners. That study 
indicates that carefully selected landfill liner materials can, when 
exposed to MWC ash leachate, be expected to function as an effective 
barrier to leachate migration. In addition, EPA is conducting ongoing, 
in situ studies of leachate from monofills receiving ash from a WTE 
facility. These studies reveal leachate concentrations of relevant 
metals are below their respective TC limits. The States have indicated 
that their data also corroborates EPA's findings.
    It is important to note that while states may allow varying liner 
designs for ash monofills or co-disposal facilities, these designs must 
still meet a performance standard intended to protect ground water 
resources. In addition, all landfills regulated under RCRA Subtitle D 
are required to perform ground-water monitoring as a way of detecting a 
release should one occur. In the event of a release to ground water, 
the owner/operator of the landfill must perform corrective action to 
clean up the ground water.
    The Agency also does not believe that the process of combining and 
treating ash within the combustion building will pose risks to human 
health. The Agency understands that many State environmental programs 
allow the ash to be combined and conditioned prior to exiting the 
combustion building for testing. These states have not indicated to the 
Agency that these current practices are presenting a risk to human 
health. In fact, the risk of exposure to fugitive ash emissions could 
be heightened if WTE facilities were required to sample or otherwise 
manage fly ash separately from bottom ash. This is because fly ash is 
generally a fine powdery substance that would become readily airborne 
were it not for such normal practices as combining the fly ash with the 
bottom ash in a quench tank to impede air emissions. Handling fly ash 
before it is combined could increase the risk of release to the 
environment.
    Further, EPA recently published proposed regulations under the 
Clean Air Act for new and existing municipal waste combustors that 
address ash. These regulations would prohibit visible emissions of 
fugitive fly ash and/or bottom ash from all ash handling activities at 
the facility. They also address the ash loading areas and ash transport 
vehicles (59 FR 48222, September 20, 1994).
    Finally, the Agency understands that some groups are concerned 
about the potential environmental risk posed by the reuse of ash in 
projects such as road base, building blocks, and sidewalks. These 
groups have expressed a desire that the Agency either ban ash reuse or 
place stringent controls on reuse. While reuse of ash currently is not 
common in the U.S. (the Agency believes that significantly less than 
ten percent of the ash generated in the U.S. is reused), the Agency 
does not believe that today's interpretation will stimulate increased 
interest in ash reuse. It is important to note that, if the WTE 
facility were required to test bottom ash and fly ash separately and 
found that either ash failed the TC determination, that facility could 
treat the ash on-site to either below TC limits or in accordance with 
the land disposal restrictions (when they are set). After this 
treatment, ash would no longer be classified as a hazardous waste and 
could be used without further hazardous waste regulation (e.g., in 
construction projects). EPA does not currently anticipate that future 
LDR treatment will differ significantly from some of the ash 
conditioning techniques currently used at WTE facilities. It also is 
important to note that many states have programs addressing the 
management of ash from WTE facilities. Currently, over one-half of the 
states address the reuse of ash.
    Should information come to EPA's attention suggesting that WTE ash 
is being managed or disposed of in a manner that is not protective of 
human health and the environment under Subtitle D, the Agency will 
consider additional actions, including issuing management guidelines 
and, if appropriate, promulgating additional regulations to address 
those situations. In addition, at individual sites, if the disposal of 
ash presents an imminent and substantial endangerment to human health 
and the environment, EPA may require responsible persons to undertake 
appropriate action under Sec. 7003(a) of RCRA.

IV. Conclusion

    In conclusion, today's interpretation of RCRA Sec. 3001(i) 
designates the point of Subtitle C jurisdiction for WTE ash at the exit 
of the combustion building following the combustion and air pollution 
control processes. The Agency believes that this reading is a 
reasonable interpretation of the statute that serves the stated goals 
of Sec. 3001(i).
    EPA emphasizes that today's decision on the appropriate location to 
make the hazardous waste determination for MWC ash is unique based on 
its interpretation of RCRA Sec. 3001(i). EPA's analysis and conclusions 
are not relevant to facilities that do not fall within the scope of 
RCRA Sec. 3001(i).
    EPA considers this action to be an interpretative rule exempt from 
the requirement for prior notice and opportunity to comment under 
section 553(b)(3)(A) of the Administrative Procedure Act, 5 U.S.C. 
553(b)(3)(A). The notice merely informs the public of EPA's view of the 
definition of ``facility'' in section 3001(i) as derived from the text 
of the statute, legislative history, and EPA's view of Congressional 
intent.

    Dated: January 27, 1995.
Carol M. Browner,
Administrator.
[FR Doc. 95-2627 Filed 2-2-95; 8:45 am]
BILLING CODE 6560-50-M