[Federal Register Volume 63, Number 216 (Monday, November 9, 1998)]
[Notices]
[Pages 60332-60343]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-29952]
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ENVIRONMENTAL PROTECTION AGENCY
[FRL-6186-7]
Notice of Availability of Draft RCRA Waste Minimization PBT
Chemical List
AGENCY: Environmental Protection Agency.
ACTION: Notice of data availability.
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SUMMARY: Today's notice makes available for public comment a list of 53
persistent, bioaccumulative, and toxic (PBT) chemicals and chemical
categories which may be found in hazardous wastes regulated under the
Resource Conservation and Recovery Act (RCRA). This notice responds to
States, industry organizations, environmental groups, and individuals
who commented on the EPA's national RCRA waste minimization policy, and
it will be used to promote voluntary waste minimization efforts which
reduce the generation of PBT chemicals found in RCRA hazardous waste by
at least half by the year 2005.
EPA requests comment on today's RCRA Waste Minimization PBT
Chemical List (also referred to as the RCRA PBT List) and the
methodology used to develop today's List. EPA is not seeking comment on
the Waste Minimization Prioritization Tool (WMPT), which is discussed
in today's notice, because the Agency has sought extensive public
review and comment on the WMPT in a previous notice. Particular issues
for comment are identified in the discussion that follows.
EPA will publish a final RCRA PBT List in 1999. This notice and the
final RCRA PBT List are a significant component of an overall PBT
strategy being developed by Agency. The overall strategy will encompass
the PBT priorities and programs identified by other EPA offices,
particularly those that cannot be addressed by single media controls
and approaches.
DATES: Please submit written comments by January 8, 1999 to the address
below.
TO OBTAIN COPIES: Copies of the draft list and all documents cited in
this notice can be obtained by calling the RCRA/Superfund/CERCLA
Hotline at (800) 424-9346, TDD (800) 553-7672 (hearing impaired), or
(703) 412-9810 in the Washington, DC metropolitan area, from 9:00 a.m.
until 6:00 p.m. Eastern time.
The draft list and supporting documents are also available in
electronic format on the Internet, and can be obtained by accessing:
WWW: http://www.epa.gov/wastemin
FTP: ftp.epa/gov
Login: anonymous
[[Page 60333]]
Password: your Internet address
TO SUBMIT COMMENTS: Please send an original and two copies of comments,
referencing docket number F-98-MMLP-FFFFF, to: RCRA Docket Information
Center, Office of Solid Waste (5305G), U.S. Environmental Protection
Agency Headquarters (EPA, HQ), 401 M Street, SW, Washington, DC 20460.
Hand deliveries of comments should be made to the Arlington, VA,
address provided below. Comments may also be submitted electronically
by sending electronic mail through the Internet to: rcra-
[email protected]. Comments in electronic format should also be
identified by the docket number F-98-MMLP-FFFFF. All electronic
comments must be submitted as an ASCII file that contains no special
characters or any form of encryption.
Commenters should not submit electronically any confidential
business information (CBI). CBI submissions must be sent under separate
cover, and must include an original and two copies. CBI must be
addressed to: RCRA CBI Document Control Officer, Office of Solid Waste
(5305W), U.S. EPA, 401 M Street SW, Washington, DC 20460.
Public comments (not including CBI) and supporting materials are
available for viewing in the RCRA Information Center (RIC), located at
Crystal Gateway I, First Floor, 1235 Jefferson Davis Highway,
Arlington, VA. The RIC is open from 9 a.m. to 4 p.m., Monday through
Friday, excluding federal holidays. To review docket materials, it is
recommended that the public make an appointment by calling (703) 603-
9230. The public may copy a maximum of 100 pages from any regulatory
docket at no charge. Additional copies cost $0.15/page.
FOR FURTHER INFORMATION CONTACT: For further information on waste
minimization, specific aspects of this notice, or public meetings
regarding this notice, contact the RCRA/Superfund/EPCRA Hotline at the
address and telephone numbers cited above, or Newman Smith at the U.S.
Environmental Protection Agency, Office of Solid Waste, Waste
Minimization Branch, 401 M Street, SW (5302W), Washington, DC 20460;
telephone: (703) 308-8757, fax: (703) 308-8433.
SUPPLEMENTARY INFORMATION:
I. Background
A. Why Is EPA Taking This Action?
EPA regulates thousands of chemicals and wastes under its multiple
environmental authorities, and has worked with States, the regulated
community, environmental groups, and individuals to make significant
progress in controlling harmful chemical releases to the environment.
Notwithstanding this important progress, recent national and
international attention has focused on persistent, bioaccumulative and
toxic (PBT) chemicals which can pose long-term problems when released
to the environment. Today's notice focuses national attention on
identifying ways to reduce the generation of PBT chemicals which may be
found in hazardous wastes regulated under RCRA.
Today's notice provides a mechanism for implementing the national
waste minimization policy of RCRA--to reduce or eliminate the
generation of hazardous waste, wherever feasible, and as expeditiously
as possible. This national policy sets a clear preference for source
reduction and recycling methods over end-of-pipe waste treatment and
disposal methods to reduce releases of harmful chemicals to the
environment. In 1988, the General Accounting Office (GAO) encouraged
EPA to focus on reducing the toxicity as well as the volume of
hazardous waste, and recommended that EPA ``establish specific,
quantifiable waste minimization goals.1 ''
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\1\ New Approach Needed to Manage the Resource Conservation and
Recovery Act; p. 57; United States General Accounting Office Report
to Congress; July 1988.
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Congress expanded this national policy in the Pollution Prevention
Act of 1990, and in Clean Air Act amendments of 1990. As Congress
stated in the Pollution Prevention Act, ``there are significant
opportunities for industry to reduce or prevent pollution at the source
through cost effective changes in production, operation, and raw
materials use. Such changes offer industry substantial savings in
reduced raw material, pollution control, and liability costs as well as
help protect the environment and reduce risks to worker health and
safety.'' The Clean Air Act promotes pollution prevention as a national
goal, and includes pollution prevention as an important element in
setting and achieving industrial emissions control standards.
EPA recognizes that progress has been made in reducing volumes of
hazardous wastes. However, today's notice expands EPA's focus to
reducing the toxicity of hazardous wastes, in addition to the volume,
by reducing RCRA PBT chemical generation at the source, rather than
relying on reducing the volume and/or toxicity of hazardous waste
through waste treatment alone. This ``PBT chemical'' approach, which is
now being addressed at the international level, recognizes that small
releases of PBT chemicals, even releases that are in compliance with
existing regulations, may nevertheless cause a build up of human health
or ecological problems over the long term.
Today's notice also responds to extensive comments EPA received
from industry organizations, environmental groups, government agencies,
and individuals during stakeholder meetings held during 1993 and 1994
to develop RCRA's Waste Minimization National Plan. Six principles for
reducing hazardous waste generation on a national level emerged from
those discussions:
Focus on source reduction as the preferred means of
environmental management, and recycling as the second preference, over
treatment and disposal of hazardous wastes;
Set environmental priorities based on risk;
Focus on reducing the chemical composition of hazardous
waste, not the volume of hazardous wastes, and carefully consider the
interrelationships between hazardous waste reduction and the reduction
of toxic releases to air and water;
Set environmental goals for source reduction and recycling
of priority chemicals, and track progress toward these goals. Promote
accountability and recognition for regulated companies, government
agencies, and other stakeholders involved in the process;
Provide flexibility to industry and States in the
selection of chemical priorities, goals for source reduction and
recycling of priority chemicals, and in selecting approaches for
achieving source reduction and recycling goals; and
Involve the public.
As a result of these discussions, EPA published the Waste
Minimization National Plan 2 (WMNP), which commits the
Agency to implementing a national waste minimization program centered
around these principles. Most importantly, the WMNP sets national goals
to:
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\2\ Waste Minimization National Plan, US EPA, 1994. EPA530-R-94-
045.
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Reduce, as a nation, the presence of the most persistent,
bioaccumulative, and toxic (PBT) chemicals in RCRA hazardous wastes 10%
by the year 2000, and at least 50 percent by the year 2005 (from a 1991
baseline);
Promote source reduction (and recycling where RCRA PBT
chemicals can not be reduced at the source) over treatment and disposal
technologies; and
[[Page 60334]]
Avoid the transfer of RCRA PBT chemicals across
environmental media.
EPA believes today's notice provides a strong foundation for
achieving these goals. The next section describes more specifically how
EPA, State governments, industry organizations, environmental groups
and citizens may participate in achieving these goals.
B. What Are Persistent, Bioaccumulative, and Toxic (PBT) Chemicals, and
Why Are They an Environmental Concern?
PBT chemicals exhibit varying degrees of three properties:
Persistent (P) chemicals do not readily break down in the environment;
bioaccumulative (B) chemicals are not easily metabolized and can
accumulate in human or ecological foodchains through consumption or
uptake; toxic (T) chemicals may be hazardous to human health or the
environment in a variety of ways, depending on the chemical and the
organism that is exposed. Examples of toxic effects include cancer and
birth defects in humans and reduced populations and altered community
structures within ecosystems. Individual chemicals may exhibit none,
some, or all of these characteristics. Chemicals which exhibit PBT
characteristics, once released to the environment, may present
increasing long-term toxic effects to human health and the environment,
even when these chemicals are released in small quantities.
RCRA PBT chemicals could be released to the environment from
several types of sources, including: Leaks from hazardous waste
treatment, storage or disposal units, authorized releases of PBTs in
treated hazardous wastes (e.g., combustion emissions or residues which
must be treated to levels which minimize threats to human health and
the environment prior to land disposal), or the combined effect of de
minimis releases of PBT chemicals permitted under multiple permitting
authorities. Because of the potential risks posed by these chemicals,
the international community recognizes the chemicals as a global
environmental concern. EPA is creating a priority in its hazardous
waste minimization program for these chemicals.
C. How Will EPA and Other Stakeholders Use the RCRA PBT List?
EPA will use the RCRA PBT List to:
Measure progress toward the national goal of reducing the
generation of RCRA PBT chemicals by at least half by the year 2005. EPA
will measure progress using data reported to the national Toxics
Release Inventory (TRI) and other nationally available data;
Report national progress on a periodic basis;
Identify and acknowledge industrial sectors which
contribute to national progress; and
Promote coordinated waste minimization programs at the
Federal, State, and local level.
EPA's 1986 Waste Minimization Report to Congress 3
concluded that promoting voluntary (rather than mandatory) waste
minimization mechanisms would be the most effective means of reducing
the volume and/or toxicity of RCRA regulated hazardous waste stream
generation. Therefore, EPA will rely on voluntary activities to promote
the reductions of RCRA PBT chemicals in hazardous waste, recognizing
that some voluntary activities may ultimately take place in conjunction
with a regulatory activity (e.g., voluntarily implementing pollution
prevention measures to meet permit compliance requirements).
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\3\ Minimization of Hazardous Waste Report to Congress, October
1986, EPA-530-SW-86-033.
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EPA will use the TRI as its primary source of data to measure and
evaluate progress toward the national goal of reducing the presence of
PBT chemicals in RCRA hazardous wastes by at least half by 2005. The
BRS will be used to provide supplemental information and analysis. As
discussed further below, the method for reporting progress is under
development, and will build on the method described in today's notice
for estimating the presence of PBT chemicals in RCRA hazardous wastes.
EPA is committing to its national RCRA PBT reduction goal to meet
the requirements of the Government Performance and Results Act (GPRA).
The GPRA sets government-wide requirements to improve performance of
government programs by ``managing for results'' and linking
programmatic budgets to performance. EPA believes its effort to reduce
long term human health and ecological problems by reducing the
generation of RCRA related PBT chemicals at the source is a crucial
GPRA goal.
EPA will work with interested States, industry organizations,
environmental groups, and citizens to promote a variety of source
reduction opportunities and programs which reduce the generation of
RCRA PBT chemicals at the source. For example, during informal
discussions, some States, companies, citizens, and other interested
parties indicated they could use the RCRA PBT List as a guide for
setting waste minimization priorities for wastes which are currently
treated or disposed. Government agencies could use the List as a
starting point to identify industrial sectors or particular chemicals
for focusing voluntary pollution prevention technical assistance
resources. Industry trade associations or individual companies could
use the list for setting waste minimization priorities and reducing
waste management costs. Individual organizations or a consortium of
organizations could use the RCRA PBT list to develop Project XL
proposals in cases where significant reductions in the generation of
RCRA PBT chemicals are possible, but regulatory flexibility is needed
to achieve the reductions (information on Project XL is available on
the Internet at www.epa.gov/projectxl). Citizen groups might use the
RCRA PBT list to promote pollution prevention as a preferred
environmental solution over waste treatment or disposal at siting
hearings or other public comment or waste management forums.
EPA will also report national progress toward meeting national
goals publicly, on a periodic basis, to encourage accountability.
D. How Will EPA Measure Progress Toward the National RCRA Hazardous
Waste PBT Reduction Goal?
EPA is considering several alternatives for developing a national
RCRA hazardous waste PBT chemical reduction measurement method. One of
the key factors in developing a measurement method is the selection of
an appropriate national database for reporting, storing and retrieving
data on PBT chemicals found in RCRA hazardous waste. EPA considered,
among others, two widely used national databases, the RCRA hazardous
waste Biennial Reporting System (BRS) and the Toxics Release Inventory
(TRI), and selected the TRI as the primary database for measuring
national PBT chemical reductions in hazardous waste. The TRI is a
publicly accepted and widely used source of data on toxic chemicals
being used, manufactured, treated, transported, and/or released to the
environment. TRI reports information on specific chemicals which may be
contained in waste. Using chemical-specific TRI information enables EPA
to measure reductions of chemical quantities found in wastes over time.
In contrast, the Biennial Reporting System provides information on
waste stream volumes, rather than chemical specific data, and will be
used for supplemental analysis in cases for chemicals which are on the
RCRA PBT List, but which are not reported in the TRI.
[[Page 60335]]
The measurement method will include only those facilities which
report data to the TRI data, and who are also RCRA hazardous waste
generators. EPA will publish and seek public comment on its draft
measurement method in 1999.
EPA will submit national interim progress reports as part of its
environmental performance reporting under the Government Performance
and Results Act. A final national progress report will be submitted for
the year 2005.
E. How Will EPA Encourage Progress Toward the National RCRA PBT
Reduction Goals?
EPA will work with States, industry, environmental groups and other
stakeholders to identify and implement a variety of implementation
approaches, including workshops, technical assistance, progress
reporting, partnership agreements, and regulatory reinvention and pilot
projects, to promote progress toward the national RCRA PBT reduction
goal. To encourage stakeholder input, EPA will conduct public meetings
to listen to stakeholder comments on the List and on technical and
programmatic measures which could be used to reduce the generation of
PBT chemicals. Information regarding public meetings can be obtained by
contacting Newman Smith by phone at (703) 308-8757, or on the Internet
at [email protected]. EPA will combine the efforts of these
interested parties into a draft national RCRA PBT reduction
implementation strategy in mid-1999. EPA will solicit public comment on
the draft strategy and will publish a final implementation strategy
later in 1999.
After publication of the final implementation strategy, EPA will
continue to work with interested parties to promote and document source
reduction and recycling successes, and measure and report progress, as
stated above.
F. How is Today's RCRA PBT List Different From Other Chemical Lists?
Today's draft RCRA PBT list differs from other lists, including
those used in the RCRA program, because of its purpose and design.
Today's draft RCRA PBT list:
Focuses on reducing RCRA PBT chemicals at the point of
generation, before they are stored, transported, treated, recycled, or
disposed on the land. Other regulatory lists are often used to set
treatment technology standards, or concentration based limits on
chemicals after treatment;
Focuses on long-term human health and ecological problems,
rather than more short term or acute human health or ecological
effects.
Will be used as a voluntary guide for identifying national
waste minimization priorities and measuring national reduction
progress, and may be used flexibly by other government agencies and
companies. It is not a regulatory list that must be adhered to by all
stakeholders.
The basis for developing the RCRA PBT list is explained in the
following sections of this notice.
G. Why Focus on the Reduction of RCRA PBT Wastes at the Point of
Hazardous Waste Generation Rather Than After Treatment?
Nearly all of the regulations promulgated under the RCRA program
set standards for safe management or cleanup of hazardous wastes after
they are generated or managed. To meet these standards, the regulated
community has frequently used ``end-of-pipe'' treatment and control
technologies. Significant progress has been made using ``end-of-pipe''
technologies, even though the costs are significant, and they do not
completely eliminate releases of toxic chemicals to the environment.
To address these issues, government agencies and the regulated
community have increased their focus on the use of source reduction and
recycling measures in place of, or as a supplement to, end-of-pipe
technologies to meet or exceed regulatory requirements and to reduce
the costs of waste management.
The organizations and individuals involved in the development of
the Waste Minimization National Plan strongly urged EPA to promote
source reduction and recycling over waste treatment and disposal to
reduce or eliminate the potential long term effects of RCRA PBT
chemicals which may build up in the environment. They recognized that,
even with stringent waste management standards, waste management units
may fail, accidents may occur during transport and handling, and de
minimis authorized releases may, nevertheless, occur. As a result,
although many sources of these chemicals may individually be in
compliance with hazardous waste and other regulations, RCRA PBT
chemicals may continue to be released and build up in the environment.
Reducing RCRA PBT chemical generation at the source is a more certain
way of reducing or eliminating potential RCRA PBT risks to the
environment, while reducing or eliminating the costs of managing
wastes.
H. How Will EPA Work With States, Industries, and Other Interested
Parties Who Have Different Priorities?
EPA encourages Federal government agencies, States, the regulated
community and other organizations to incorporate the priorities
contained in today's proposed RCRA PBT list in their current
environmental priorities and programs. EPA is aware that some
organizations have chemical reduction priorities which differ in
varying degrees from today's List. Examples of chemical priority lists
from 15 State, tribal and international organizations are in the docket
for today's notice. Based on a comparison of these lists with today's
draft RCRA PBT List, EPA believes many organizations will find
chemicals that are common to their own and today's List.
EPA believes establishing common priorities provides an opportunity
for progress toward the national RCRA PBT reduction goal. Therefore,
EPA will actively work with States, industry, environmental groups and
other interested parties to identify and integrate, to the extent
possible, common RCRA PBT reduction priorities and multimedia
implementation approaches to promote progress toward the national RCRA
PBT chemical reduction goals.
EPA believes States should use flexibility available through the
National Environmental Performance Partnership System (NEPPS) to
address priorities for multi-media, multi-programmatic environmental
protection, including the priorities contained in today's List. EPA has
included a goal, similar to the WMNP goal, as a Core Performance
Measure in the NEPPS program. This goal seeks to ``decrease the
quantity of waste generated, decrease the toxicity of waste generated,
and increase recycling of wastes.
II. Waste Minimization Prioritization Tool Revisions and
Information Stewardship
A. What is the Waste Minimization Prioritization Tool? When and How Was
it Revised?
The Waste Minimization Prioritization Tool (WMPT), a Windows-based
chemical hazard screening tool developed by EPA, generates relative
rankings of chemicals based on their potential to cause chronic human
health and ecological problems. The WMPT generates rankings based on
four sets of chemical properties, including: Chemical persistence,
bioaccumulation potential, chronic human and ecological toxicity, and
chemical mass. The last property,
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chemical mass, is an optional variable that can be used at the user's
discretion to generate rankings.
This section outlines the process EPA used to seek public review of
the WMPT, an outline of comments received, and a summary of the changes
made to the WMPT in response to the comments. EPA used WMPT rankings
based on the first three of the four properties noted above as input to
the development of the RCRA PBT List. The reasons for this are
described in the following sections.
EPA released Beta Version 1.0 of the WMPT software \4\ and the
accompanying User's Guide \5\ for public comment on June 23, 1997.\6\
In addition to the public comments received in the docket, EPA received
comments from several other sources during the public comment period,
including: peer review comments obtained from technical experts in
industry, environmental groups, and states during a focus group meeting
in September 1997; comments from an intra-Agency technical workgroup
that reviewed the WMPT as a means of identifying ``PBT'' chemicals; and
comments from a WMPT pilot project conducted by EPA Region 9 in the
Santa Clara Valley, California. Comments were received on many facets
of the WMPT. EPA received a variety of comments, including
recommendations to:
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\4\ EPA530-C-97-003.
\5\ Waste Minimization Prioritization Tool (Beta Test Version
1.0): User's Guide and System Documentation (EPA530-R-97-019).
\6\ 62 FR 33868.
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Modify the weighting and aggregation of persistence,
bioaccumulation, human toxicity, and ecological toxicity scores in the
WMPT.
Modify the WMPT to better represent actual risk, as
opposed to hazard.
Revise the data quality hierarchies for persistence and
bioaccumulation data to place preference on measured data (e.g., data
gathered in laboratory tests and field studies) rather than predicted
data (i.e., data derived from predictive models).
Improve the quality of data that are used as the basis for
scoring by updating existing Agency data sources (e.g., the Integrated
Risk Information System) and by incorporating new sources of data
currently available to EPA or obtainable from non-EPA sources.
Provide the rationale behind the ``fenceline values''
(i.e., thresholds) that separate low, medium, and high scores.
Score metals based on bioavailability rather than
environmental persistence.
Modify the persistence scoring approach to consider
partitioning to media other than water (e.g., to air).
Modify the current low/medium/high ``binning'' approach to
include more than three bins and better discriminate among chemicals in
scoring.
Provide a better indication of the uncertainty associated
with chemical values and scores by providing additional information on
the sources of data used in the WMPT and on the quality of the data.
Complete a peer review of the WMPT.
Provide a process for modifying data values and scores in
the WMPT as new data become available.
An intra-Agency WMPT Workgroup was established to review the
comments and provide recommendations on changes to the WMPT. With the
purpose in mind of preparing chemical rankings for development of the
RCRA PBT List, the Workgroup focused on addressing technical and
scientific comments that would potentially affect RCRA PBT chemical
scores. Comments that would not affect RCRA PBT chemical scores (e.g.,
comments recommending improving the user-friendliness of the Tool and
User's Guide) were deferred until a later time.
EPA considered the comments and recommendations. As a result, the
following changes were made to the WMPT:
For each chemical, the higher of the human health and
ecological concern scores (previously referred to as human health and
ecological risk potential scores) was used to indicate overall concern
for the purpose of developing the RCRA PBT List, rather than adding the
two scores together.
Measured data were given preference over predicted data in
deriving persistence and bioaccumulation scores. Adjustments in data
preferences were made in scoring bioaccumulation potential, (i.e.,
bioaccumulation factors were given preference over bioconcentration
factors, and the log of the octanol-water partition coefficient was no
longer used).
New persistence, bioaccumulation, human toxicity, and
ecological toxicity data (which meet our data quality standards) from a
number of sources were included in the WMPT.
The fenceline values separating low, medium, and high
scores for persistence, bioaccumulation, and toxicity were better
documented; in some cases, the fenceline values were recalculated.
A multimedia partitioning model was used to estimate the
partitioning of chemicals to air, water, soils, and sediments and to
calculate overall environmental persistence, rather than estimating
persistence in surface water alone.
Data transparency was improved by better documenting data
sources and indicating the preference levels for the underlying data
used for scoring; some data that could not be sufficiently documented
for the purpose of the WMPT were removed.
The comments received and EPA's responses are discussed in detail
in the Waste Minimization Prioritization Tool Comment Response Document
for the RCRA Waste Minimization PBT Chemical List Docket (referred to
as the WMPT Comment Response Document below). This document is
available in RCRA docket #F-98-MMLP-FFFFF and at EPA's Internet home
page at www.epa.gov/wastemin.
After making the changes to the WMPT outlined above, EPA prepared
spreadsheets containing revised data and scoring information. This
information was used as input for developing the RCRA PBT List. As a
result of the expanded and improved data used in the WMPT,
approximately 2,900 chemicals receive human health or ecological
concern scores, compared with approximately 1,800 chemicals in the beta
version of the WMPT. Of the 2,900 chemicals, 122 chemicals score from 7
to 9 (i.e., relatively high) for human health concern and 666 score
from 7 to 9 for ecological concern. Some score from 7 to 9 for both
criteria. Altogether, 681 chemicals score from 7 to 9 for one or both
of the two scores.
EPA has placed in the docket (F-98-MMLP-FFFFF)
a document titled Waste Minimization Prioritization Tool Spreadsheet
Document for the RCRA Waste Minimization PBT Chemical List Docket
(referred to below as the WMPT Spreadsheet Document) that: (1) explains
changes made to the WMPT as a result of the public and peer review
processes, and (2) displays spreadsheets and scoring information for
1,300 chemicals which received a score of 6 or above for human health
or ecological concern. This document is also available at EPA's
Internet home page at www.epa.gov/wastemin.
Information on the approximately 3,900 chemicals that scored from 3
to 5 or that are unscored is not included in the docket, since these
chemicals did not appear to be appropriate candidates for the RCRA PBT
List. Information on these chemicals will be provided in a future
version of the WMPT.
[[Page 60337]]
The WMPT Comment Response Document and WMPT Spreadsheet Document
are included in today's docket to provide the reader with background
information on changes made to the WMPT and its use as a foundation for
the development of today's draft RCRA PBT List. The WMPT spreadsheets
contained in the docket are not intended to support other applications
at this time. EPA is not requesting public comment on this information,
since the WMPT has already received widespread and comprehensive public
review. Additional applications beyond supporting the development of
today's draft RCRA PBT List will be discussed when the WMPT is re-
released in 1999. That release of the WMPT revisions will include the
scoring changes used in today's notice and improvements to the tool's
software features.
B. How Will Ensure Stewardship of the Waste Minimization Prioritization
Tool and Underlying Scientific Information?
EPA is committed to coordinating the collection of environmental
data and to making it available to the public through the Agency's
``Reinventing Environmental Information Initiative.'' In 1997,\7\ EPA
announced three important information management reforms, which:
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\7\ Administrator Carol Browner and Deputy Administrator Fred
Hansen. EPA Common Sense Initiative Meeting. July 21, 1997.
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Establish key data standards to improve the value of
environmental information, data sharing and integration;
Provide universal voluntary access to electronic reporting
to reduce burdens and improve data quality and timeliness; and
Implement these data standards and electronic reporting
reforms in the Agency's national systems in partnership with the states
through the One Stop Program.
Consistent with these principles, EPA commits to maintaining sound
scientific information as a foundation for reducing RCRA PBT
generation. The EPA has taken measures to practice principles of
information stewardship in the development of today's draft RCRA PBT
List by:
Identifying the most up to date and documented information
that is readily available;
Excluding undocumented scientific information;
Seeking expert advice to make assumptions, assess data
quality and weigh contradictory information;
Making information about data sources, data quality,
assumptions publicly known;
Inviting public review and comment on the data used; and
Making appropriate adjustments to information.
The Office of Solid Waste intends to follow these principles of
information stewardship to ensure the integrity of data used in the
Waste Minimization Prioritization Tool. As noted above, EPA will
release an updated, user-friendly version of the WMPT in 1999, and will
discuss how best to maintain stewardship of this tool and the
underlying data with interested organizations and individuals at that
time.
III. Development of Today's Draft RCRA PBT List
The Agency followed several steps to develop today's draft RCRA
Waste Minimization PBT Chemical List (referred to as the RCRA PBT List
below). Each of these steps is discussed in more detail below.
A. How Were Initial Candidates for the RCRA PBT List Identified?
The first step in developing today's draft RCRA PBT List was to
assemble an initial list of candidate chemicals for further
examination. EPA drew from two sources to establish this initial
candidate chemical list: (1) The Waste Minimization Prioritization Tool
discussed above, and (2) a composite list of PBT chemicals identified
as priorities by other EPA program offices. This step is discussed
below, and is described in the Chemical Screening Report for the RCRA
PBT List Docket (referred to below as the Screening Report), which is
located in RCRA docket number F-98-MMLP-FFFFF.
1. Candidates From the Waste Minimization Prioritization Tool
EPA selected as candidates from the WMPT those chemicals which
scored 7 or higher (on a scale of 3-9) for either human health concern
or ecological concern. A total of 681 chemicals scored in the WMPT met
this criterion. EPA then grouped certain polycyclic aromatic
hydrocarbons into a single polycyclic aromatic hydrocarbons category,
and grouped individually listed polychlorinated biphenyls with the
existing polychlorinated biphenyls category, resulting in a total of
660 candidate chemicals and chemical groups.
EPA selected the cut-off score of 7 for human health or ecological
concern in order to ensure that chemical candidates represent at least
moderately high concern for PBT. In order to attain a score of 7, a
chemical must receive the highest WMPT score for at least two of the
three factors (P, B and T) or the highest score for one factor and
moderate scores for the other two factors. EPA believes that a higher
cut-off score would be overly restrictive, eliminating from further
consideration many chemicals of significant RCRA PBT concern, while a
lower cut-off score would be unnecessarily expansive, drawing in many
chemicals which would not represent a sufficiently high level of RCRA
PBT concern for this national PBT waste minimization effort.
2. PBT Priorities Identified by Other EPA Programs
In addition to drawing candidate chemicals from the WMPT, EPA
considered PBT chemical priorities identified by other EPA programs
through internal PBT coordination efforts. This list of 34 chemicals
included 18 chemicals which scored below 7 for human health or
ecological concern in the WMPT, and 16 chemicals that were either not
included in the WMPT, or were included, but were not scored because
there were insufficient data. These chemicals were included in the
candidate pool for development of the RCRA PBT List to determine the
extent to which they may also be a RCRA PBT waste minimization
candidate. Including these 34 chemicals in the candidate pool brought
the total number of candidate chemicals and chemical groups to 694.
B. What Inclusion/Elimination Criteria Were First Applied to the
Candidate Chemicals?
After assembling the initial candidate chemical list, EPA
eliminated chemicals that would not be good candidates for RCRA waste
minimization efforts because they are unlikely to be present in RCRA
hazardous waste in significant quantities, or are present, but are not
highly toxic. Three criteria were used to screen out these chemicals:
pesticides which are banned from production and use; chemicals with
zero reported quantities in waste; and chemicals with low WMPT toxicity
scores. This step is summarized below, and is described in detail in
the Screening Report.
1. Banned Pesticides
EPA first eliminated those chemicals that are pesticides banned
from use in the United States and are not known to have other, non-
pesticidal sources or uses. This screen eliminated 28 chemicals from
further consideration, including a number of well-known PBT chemical
priorities such as DDT. EPA
[[Page 60338]]
did not eliminate from further consideration pesticides that are
``severely restricted,'' but not banned in the U.S.
2. Chemicals Not Present in RCRA Wastes
EPA also eliminated from further consideration chemicals that are
not likely to be found in RCRA hazardous waste, based on quantities
reported in the Agency's Toxics Release Inventory (TRI) database \8\
and the National Hazardous Waste Constituent Survey (NHWCS).\9\
Chemical quantities reported in the TRI were adjusted to estimate
quantities present in hazardous waste streams by: including only TRI
reporters who had RCRA ID numbers; in the case of underground injected
wastes, including only TRI reporters with RCRA ID numbers who also had
RCRA UIC (Underground Injection [well] Code) ID numbers; and excluding
air and water releases from TRI production-related wastes. This screen
eliminated 510 candidate chemicals, leaving 156 chemicals to be
considered further in developing the RCRA waste minimization list. Some
highly PBT chemicals were eliminated in this step (e.g., dioxin)
because they are generated in very small quantities, which are not
reported in the TRI. These were flagged and re-examined in the last
step, described below in Section E.
---------------------------------------------------------------------------
\8\ U.S. EPA. 1997. 1991 and 1995 Toxic Release Inventory (TRI)
Data.
\9\ U.S. EPA. 1998. National Hazardous Waste Constituent Survey.
Office of Solid Waste. Washington, DC. This is a survey of chemical
constituent presence in hazardous waste streams managed by RCRA
treatment, storage and disposal facilities.
---------------------------------------------------------------------------
3. Chemicals With Low Toxicity
Finally, EPA checked to ensure that none of the 156 chemicals
passing the above screens became a candidate based on high P and/or B
scores, but had a low score for human health or ecological toxicity.
The rationale for this screen was that, even though some chemicals may
persist or bioaccumulate in the environment, they should not be a
candidate for the national RCRA PBT List if the chemical is not likely
to be at least moderately toxic in the environment. None of the 156
candidate chemicals had low toxicity scores.
C. How Were the Remaining Candidate Chemicals Ranked?
To identify the best candidate chemicals for RCRA source reduction
and recycling efforts, EPA developed four ``primary'' criteria for
ranking the remaining chemicals. These criteria included: (1) Each
chemical's PBT score from the WMPT; (2) chemical quantity and
prevalence (or frequency of occurrence) in hazardous waste; (3)
evidence that the chemical is present in the environment, particularly
at levels of concern; and (4) the degree to which the chemical is a
concern to the RCRA program.
Ranking the candidate chemicals was completed by: Summing
subcriteria scores within each of the four primary criteria discussed
above; converting the scores for each primary criterion to a 25 point
scale (i.e., the Agency gave equal weight to the four primary
criteria); summing scores for each chemical; and arranging the
chemicals in rank order on a scale of 1-100. The individual subcriteria
were scored on a 0, 1, 2, 3 scale (except where noted). The values on
this scale were assigned to different ranges of data values by
examining the underlying data distributions and using natural breaks in
the distributions or creating comparably sized groups. The process used
to score and rank chemicals in this step is summarized below and is
described in detail in the Chemical Ranking Report for the RCRA PBT
List Docket (referred to below as the Ranking Report), located in RCRA
docket number F-98-MMLP-FFFFF.
1. PBT Scores
In this step, each candidate chemical was scored based on the
higher of its WMPT human or ecological concern scores. The scoring
approach is provided in Table 1 below. Each chemical with a WMPT score
was assigned a subcriterion score from 0-3. Chemicals not scored in the
WMPT were ranked by summing and normalizing scores for the remaining
three primary criteria, to compensate for the missing WMPT score.
Table 1.--PBT Characteristics Scoring
------------------------------------------------------------------------
Sub-
PBT characteristics subcriterion criterion
score
------------------------------------------------------------------------
Higher of WMPT human health and ecological concern scores
equals 9.................................................... 3
Higher of WMPT human health and ecological concern scores
equals 8.................................................... 2
Higher of WMPT human health and ecological concern scores
equals 7.................................................... 1
WMPT human health and ecological concern scores are both less
than 7...................................................... 0
------------------------------------------------------------------------
2. Quantity and Prevalence
The Agency believes that RCRA PBT chemicals which occur in greater
quantities, or are more prevalent, in hazardous waste should be given a
higher national priority for RCRA waste minimization than other PBT
chemicals. Therefore, EPA assigned higher scores to chemicals with
greater quantity, or prevalence, in hazardous waste.
EPA used TRI and NHWCS data to determine chemical quantities in
waste and used Biennial Reporting System (BRS) data 10 to
determine waste stream quantities associated with each chemical. EPA
also used TRI, NHWCS, and BRS data to determine the number of
facilities generating or managing each chemical in hazardous waste.
---------------------------------------------------------------------------
\10\ U.S. EPA. 1997. Biennial Reporting System Flat Files.
Office of Solid Waste and Emergency Response, Washington, DC.
---------------------------------------------------------------------------
TRI quantity and prevalence data were adjusted to identify and
estimate chemical quantities and prevalence in RCRA hazardous waste by:
(1) Including only TRI reporters who had RCRA ID numbers; (2) in the
case of underground injected wastes, including only TRI reporters with
RCRA ID numbers who also had RCRA UIC ID numbers; and (3) excluding air
and water releases from TRI production-related waste. NHWCS quantity
and prevalence data were used only where TRI quantity and prevalence
data were unavailable. To estimate the quantities of BRS waste streams
and number of generators associated with particular chemicals, EPA used
the RCRA Chemical-Waste Code Crosswalk,11 which identifies
hazardous waste codes that may be associated with particular chemicals.
---------------------------------------------------------------------------
\11\ The RCRA Chemical-Waste Code Crosswalk (EPA530-D-97-005) is
from the beta version of the WMPT; it is included in RCRA Docket #F-
98-MMLP-FFFFF. Chemicals not listed in the crosswalk were not
evaluated on the BRS-based criteria.
---------------------------------------------------------------------------
The TRI reports quantity information on both metals and metal
compounds. The quantity information reported for a metal compound only
includes the metal component of the compound. In keeping with this
approach for metal reporting, EPA added together the quantities
reported in TRI as metals and metal compounds.
The TRI/NHWCS score and the BRS score were weighted equally (i.e.,
were added together and divided by two) in deriving both the quantity
and prevalence subcriteria scores. If the BRS score was missing for a
chemical, the TRI/NHWCS score was used as the quantity or prevalence
subscriterion score. The quantity subcriterion score was added to the
prevalence subcriterion score in deriving the
[[Page 60339]]
quantity/prevalence criterion score for each chemical. The scoring for
quantity and prevalence is presented in Table 2 below.
Table 2.--Quantity and Prevalence Scoring
------------------------------------------------------------------------
Subcriterion
Quantity/prevalence subcriterion Value range score
------------------------------------------------------------------------
TRI chemical quantity (pounds/ Greater than 10,000,000. 3
yr).
1,000,000-10,000,000.... 2
1-1,000,000............. 1
Less than 1............. 0
NHWCS chemical quantity (pounds/ Greater than 1,000,000.. 3
yr).
100,000-1,000,000....... 2
1-100,000............... 1
Less than 1............. 0
BRS waste stream quantity (tons/ Greater than 100,000,000 3
yr).
10,000,000-100,000,000.. 2
1-10,000,000............ 1
Less than 1............. 0
TRI number of generators........ More than 99............ 3
10-99................... 2
1-9..................... 1
0....................... 0
NHWCS number of handlers \12\... More than 10............ 3
5-10.................... 2
1-4..................... 1
0....................... 0
BRS number of generators........ More than 9,999......... 3
1,000-9,999............. 2
1-999................... 1
0....................... 0
------------------------------------------------------------------------
3. Environmental Presence12
The Agency believes that PBT chemicals which are detected in the
environment more frequently than other chemicals should be given higher
priority for reduction through source reduction and recycling. EPA
ranked each chemical's ``presence in the environment'' using
measurement indicators contained in the following three national
databases: (1) EPA's Fish Advisory Database 13 (EPA used the
most current year of fish advisory data in the U.S.--1997); (2) EPA's
National Sediment Inventory 14 (EPA used data on sediment
contamination in the U.S. for all years contained in the database; and
(3) the Agency for Toxic Substances and Disease Registry's Hazdat
Database 15 (EPA used data on chemicals found in the toxic
cleanup sites identified on the EPA's Superfund National Priority List
(NPL) covered under the Comprehensive Environmental Response,
Compensation and Liability Act.
---------------------------------------------------------------------------
\12\ The number of handlers is the number of RCRA treatment,
storage, or disposal facilities that managed a chemical, rather than
the number of generators of the chemical.
\13\ U.S. EPA. 1998. 1997 National Listing of Fish Consumption
Advisories. Office of Water, Washington, DC. www.epa.gov/OST/
fishadvice. June.
\14\ U.S. EPA. 1997. The Incidence and Severity of Sediment
Contamination in Surface Waters of the United States; Volume 1: The
National Sediment Quality Survey. Office of Science and Technology,
Washington, DC. EPA/823/R-97/006.
\15\ Agency for Toxic Substances and Disease Registry. 1998.
Hazardous Substance Release/Health Effects Database. website:
atsdr1.atsdr.cdc.gov/8080/hazdat/html.
EPA used the ATSDR data since no comparable data were readily
available from RCRA corrective action sites.
---------------------------------------------------------------------------
Scores were developed using the scoring approach in Table 3 below.
Each environmental presence subcriterion was scored from 0-3. The
scores for the three subcriteria were weighted equally (in this case
being added together) in deriving an environmental presence criterion
score for each PBT chemical.
Table 3.--Environmental Presence Scoring
------------------------------------------------------------------------
Environmental presence Subcriterion
subcriterion Value range score
------------------------------------------------------------------------
Fish Advisory Database (1997 More than 99 advisories. 3
data).
10-99 advisories........ 2
1-9 advisories.......... 1
No advisories........... 0
National Sediment Inventory More than 999 detections 3
(1980-1993).
100-999 detections...... 2
1-99 detections......... 1
No detections........... 0
ATSDR HazDat Database (all NPL More than 499 sites..... 3
sites).
100-499 sites........... 2
1-99 sites.............. 1
No sites................ 0
------------------------------------------------------------------------
[[Page 60340]]
4. RCRA Programmatic Concern
EPA believes PBT chemicals that are of particular concern to the
RCRA program should be given higher priority in developing today's
draft RCRA PBT List than PBT chemicals identified in the WMPT or other
programs that are not a particular concern to the RCRA program. To
identify ``RCRA-relevant'' PBT chemicals, EPA selected the candidate
PBT chemicals which are found on one or more regulatory lists used in
the RCRA hazardous waste generation, management, and corrective action
programs. The scoring scheme for these chemicals is provided in Table 4
below.
EPA used a wider subcriterion scoring range (0-4) for this
criterion to reflect the broad range of RCRA programmatic concerns.
This wider scoring range was then normalized (i.e., was converted to a
25 point scale) so that the criterion was weighted equally with the
other primary criteria.
A score of 4 was assigned to PBT chemicals that: (1) Are capable of
forming dense nonaqueous phase liquids (DNAPLs) that make groundwater
cleanups particularly difficult; 16 (2) are identified as
``difficult to treat'' chemicals under the Land Disposal Restrictions
(LDR) program; 17 or (3) are targeted for co-regulation
under RCRA and the Clean Air Act Section 112 in EPA's proposed maximum
achievable control technology (MACT) combustion rule for hazardous
waste incinerators, cement kilns or light weight aggregate kilns, or
are currently regulated under the RCRA boilers and industrial furnaces
(BIF) rule (since chemicals regulated under these rules could
potentially be transferred to the air or soil media after
combustion).18, 19
---------------------------------------------------------------------------
\16\ See the following three references:
Cohen, R.M., J.W. Mercer, and J. Matthews. 1993. DNAPL Site
Evaluation. CRC Press, Boca Raton, FL.
U.S. EPA. 1993. Evaluation of the Likelihood of DNAPL Presence
at NPL Sites, National Results. Office of Solid Waste and Emergency
Response, Washington, DC. EPA/540/R-93/073.
U.S. EPA. 1991. Estimating Potential for Occurrence of DNAPL at
Superfund Sites. Office of Solid Waste and Emergency Response,
Environmental Research Laboratory, Washington, DC. EPA publication
9355-4-07FS.
\17\ Eby, E. 1998. Internal communication. Waste Treatment
Branch, Office of Solid Waste, U.S. EPA. May.
\18\ U.S EPA. 1991. Burning of Hazardous Waste in Boilers and
Industrial Furnaces: Final Rule. 56 FR 7134. February 21.
\19\ U.S. EPA. 1996. Revised Standards for Hazardous Waste
Combustors: Proposed Rule. 61 FR 173858. April 19.
---------------------------------------------------------------------------
Chemicals which are not on any of the regulatory lists discussed in
the previous paragraph, but are on the Toxicity Characteristic (TC)
list (40 CFR 261.24) or the Appendix VII list of chemicals, which is
used as the basis for hazardous waste listings (40 CFR part 261), are
assigned a score of 3. The Agency has historically taken regulatory
actions in the RCRA program based on risk assessments and damage cases
involving these chemicals.
If a chemical was not on any of the lists noted above but is
regulated under RCRA based on technological standards rather than risk-
based standards (i.e, chemicals covered by the Universal Treatment
Standards (UTS) list (40 CFR 268.48), it was assigned a score of 2. If
a chemical was not on any of the lists noted above, but was on the RCRA
P list of acute hazardous waste (40 CFR 261.33), the U list of toxic
waste (40 CFR 261.33), the Appendix VIII hazardous waste constituent
list (40 CFR part 261), or the Appendix IX ground water monitoring list
(40 CFR part 264), the chemical was assigned a score of 1. These
chemicals are regulated under RCRA, but are of lesser concern. For
instance, Appendix IX chemicals are used to set permit parameters.
However, if they are not on the lists mentioned above, are of lesser
concern. In addition, although P list chemicals are of concern due to
their acute hazards, they are generated infrequently and usually in
small quantities.
Chemicals not found on any of the lists discussed above received a
0 score. The scoring of subcriteria for RCRA Programmatic Concern is
summarized in Table 4 below.
Table 4.--RCRA Programmatic Concern Scoring
------------------------------------------------------------------------
Subcriterion
RCRA programmatic concern subcriterion score
------------------------------------------------------------------------
Chemicals contained on any of the following lists: (1)
Chemicals that can form dense non-aqueous phase liquids;
(2) chemicals identified as ``difficult to treat,'' or
(3) chemicals regulated under the MACT rule for hazardous
waste incinerators, cement kilns and light weight
aggregate kilns, or the RCRA rule for boilers and
industrial furnaces...................................... 4
Presence on the toxicity characteristic list or the
Appendix VII list of chemicals serving as the basis for
hazardous waste listings................................. 3
Presence on the land disposal restrictions universal
treatment standards list................................. 2
Presence on the RCRA P list of acute hazardous waste, the
U list of toxic waste, the Appendix VIII hazardous waste
constituent list, or the Appendix IX ground water
monitoring list.......................................... 1
Chemical not present on any of the above RCRA lists....... 0
------------------------------------------------------------------------
[[Page 60341]]
The Agency conducted limited sensitivity testing of the ranking
methodology by observing changes in the rankings in response to
modifying the ranking criteria. Several scenarios were tested,
including eliminating each of the primary criteria in turn and
eliminating both the RCRA Relevance and Environmental Presence criteria
together.
In general, the methodology appeared to be fairly robust in its
identification of the top ranking chemicals. Scenarios which
alternatively dropped the RCRA Relevance, Quantity/Prevalence, and the
PBT Score criteria each displaced roughly 10 chemicals from the top 50.
Elimination of the Environmental Presence criterion had less of an
impact on the rankings than dropping the other criteria. This indicates
that, when one of the four criteria is removed from the ranking method,
the remaining criteria and data support the ranking to a substantial
degree.
In a more drastic sensitivity scenario, dropping two of the
criteria, RCRA Relevance and Environmental Presence, together
substantially altered the rankings--30 chemicals in the top 50 were
displaced, and several chemicals changed by more than 50 rank
positions. These results are not surprising considering the substantial
change to the scoring method (half of the criteria are removed). For
further information, see the report Revised Chemical Ranking
Methodology Testing Results in RCRA docket number F-98-MMLP-FFFFF.
D. What Cutoff Was Applied to the Ranked Chemicals to Obtain the Draft
RCRA PBT List?
After ranking the 150 candidate chemicals, EPA selected a cutoff
value to identify the ``top tier'' of chemicals for tracking on a
national level. EPA narrowed the candidate list to the 61 chemicals
which had a score of 50 points (the half way point on the scoring
scale) as a basis for inclusion in the draft RCRA PBT List proposed
today. EPA determined that a national list of 50 to 60 chemicals was
appropriate, given limited Agency, State, and private resources to
reduce and measure these chemicals.
E. What Final Adjustments Were Made to the Draft RCRA PBT List?
As a final step, EPA added and removed certain chemicals from the
list for the particular reasons described below. Adding and removing
chemicals reduced the draft RCRA PBT List from 61 to 53 chemicals.
1. U.S./Canada Binational Agreement Level 1 Chemicals
EPA added dioxins, furans, and octachlorosytrene to the RCRA PBT
List because of their high priority on the ``Level 1'' list of the
U.S./Canada Binational Agreement.20 Four other Level 1
chemicals were already among the top tier chemicals for the RCRA PBT
List.21 Nine chemicals on the Level 1 list, including eight
banned pesticides and alkyl lead, are excluded because they are either
no longer produced (e.g., banned pesticides), or are found in very
limited quantities in wastes from only a few production processes
(e.g., alkyl lead).22 In either case, these chemicals are
not very amenable to reductions through waste minimization. The
Binational Agreement and the Level 1 list are available for review in
RCRA docket number F-98-MMLP-FFFFF.
---------------------------------------------------------------------------
\20\ U.S. EPA. 1997. Great Lakes Binational Toxics Strategy.
Great Lakes National Program Office, Chicago, IL. www.epa.gov/
grtlakes/p2/bnsintro.html
\21\ These four chemicals include hexachlorobenzene, mercury and
compounds, PCBs, and benzo(a)pyrene. PCBs were subsequently removed
from the proposed RCRA PBT List (see discussion below), and
benzo(a)pyrene was included in the category polycyclic aromatic
hydrocarbons.
\22\ The eight banned pesticides include aldrin, dieldrin,
chlordane, DDT, DDD, DDE, toxaphene, and mirex.
---------------------------------------------------------------------------
2. Chemicals With Low or no PBT Scores
The Agency initially added chemicals identified by other EPA
programs to the candidate list to provide a comprehensive starting
point in the RCRA PBT List development process. At this final step in
the RCRA PBT List development process, six chemicals were removed for
the following reasons. Five of the chemicals--tetrachlorethylene,
trichlorethylene, methylene chloride, 1,2-dichloroethane, and 1,1,2,2-
tetrachloroethane--were removed because their WMPT PBT scores are below
7. Although individual States may wish to pursue reductions in these
chemicals, EPA determined they are not among the most highly toxic for
a national list. The sixth, silver, was removed because it has no PBT
score.
3. PCBs
The Agency removed the PCB chemical group from the RCRA PBT List
because production of PCBs is banned in the U.S. and waste minimization
opportunities for PCBs in process waste streams are believed to be very
limited.
4. Di-n-octyl Phthalate and Butyl Benzyl Phthalate
The Agency previously removed both of these chemicals from the
EPCRA Section 313 List of Toxic Chemicals in response to delisting
petitions. Consequently, the Agency examined these chemicals more
closely to determine whether to continue to include them on the draft
RCRA PBT List. The Agency decided to remove di-n-octyl phthalate from
the draft RCRA PBT List because data developed in response to that
delisting petition indicated that the human and ecological toxicity
data were not conclusive. However, EPA has retained butyl benzyl
phthalate on the draft RCRA PBT List because the ecological toxicity
criteria considered for delisting from the EPCRA list were different
than the criteria used in the WMPT for determining high levels of
concern for ecological toxicity.
5. Hexachlorocyclohexane Isomers
The Agency removed the alpha, beta, and delta hexachlorocyclohexane
isomers and retained the gamma isomer. The gamma isomer is believed to
be the predominant PBT isomer in waste streams, and achieving waste
minimization for this isomer would result in reductions in the other
isomers as well.
IV. EPA's Draft RCRA Waste Minimization PBT Chemical List and
Issues for Public Comment
A. Which Chemicals Are Included on the Draft RCRA PBT List?
Table 5 below presents EPA's draft RCRA PBT List. The chemicals are
listed in alphabetical order. No rank ordering is intended in this
List, and, in fact, the List treats these chemicals as equal
environmental priorities. The Chemical Abstract Service Registry Number
(CASRN) is also shown, where available.
Table 5.--Draft RCRA PBT List
------------------------------------------------------------------------
CASRN
------------------------------------------------------------------------
Dioxins and Furans:
[[Page 60342]]
Dioxins (PCDD)...................................... ..............
Furans (PCDF)....................................... ..............
Chlorinated Solvents:
Chloroform.......................................... 67-66-3
1,1-Dichloroethane.................................. 75-34-3
1,1,1-Trichloroethane............................... 71-55-6
Chlorobenzenes:
1,2-Dichlorobenzene................................. 95-50-1
1,3-Dichlorobenzene................................. 541-73-1
1,4-Dichlorobenzene................................. 106-46-7
1,2,4-Trichlorobenzene.............................. 120-82-1
1,2,4,5-Tetrachlorobenzene.......................... 95-94-3
Pentachlorobenzene.................................. 608-93-5
Hexachlorobenzene................................... 118-74-1
Other Halogenated Organics:
4-Bromophenyl phenyl ether.......................... 101-55-3
Hexachlorobutadiene................................. 87-68-3
Octachlorostyrene................................... 29082-74-4
Pesticides
alpha-Endosulfan.................................... 959-98-8
beta-Endosulfan..................................... 33213-65-9
Heptachlor.......................................... 76-44-8
Heptachlor epoxide.................................. 1024-57-3
gamma-Hexachlorocyclohexane......................... 58-89-9
Methoxychlor........................................ 72-43-5
Pentachloronitrobenzene............................. 82-68-8
Pentachlorophenol................................... 87-86-5
2,4,5-Trichlorophenol............................... 95-95-4
Organonitrogens:
Nitrobenzene........................................ 98-95-3
Nonhalogenated Phenolics:
Phenol.............................................. 108-95-2
2,4,6-tris-(1,1-Dimethylethyl)phenol................ 732-26-3
Phthalate esters:
Bis-(2-ethylhexyl) phthalate........................ 117-81-7
Butylbenzyl phthalate............................... 85-68-7
Dibutyl phthalate................................... 84-74-2
Polycyclic aromatic hydrocarbons**:
Acenaphthene........................................ 83-32-9
Acenapthylene....................................... 208-96-8
Anthracene.......................................... 120-12-7
Benzo(g,h,l)perylene................................ 191-24-2
Fluoranthene........................................ 206-44-0
Fluorene............................................ 86-73-7
2-Methylnaphthalene................................. 91-57-6
Naphthalene......................................... 91-20-3
PAH group (as defined in TRI).......................
Phenanthrene........................................ 85-01-8
Pyrene.............................................. 129-00-0
Metals
Antimony............................................ 7440-36-0
Arsenic............................................. 7440-38-2
Beryllium........................................... 7440-41-7
Cadmium............................................. 7440-43-9
Chromium............................................ 7440-47-3
Copper.............................................. 7440-50-8
Lead................................................ 7439-92-1
Mercury............................................. 7439-97-6
Nickel.............................................. 7440-02-0
Selenium............................................ 7782-49-2
Zinc................................................ 7440-66-6
Cyanide............................................ 57-12-5
------------------------------------------------------------------------
** The Toxics Release Inventory reports some polycyclic aromatic
hydrocarbons (PAHs) as a group, and reports other PAHs individually.
The 10 individual PAHs listed in this table are not included in the
TRI PAH group. See the Screening Report for a list of PAHs included in
the TRI PAH group.
[[Page 60343]]
B. What Issues is EPA Requesting Public Comment On?
The Agency welcomes public comment on any aspect of the methodology
used to develop the draft RCRA PBT List, including the data sources,
ranking criteria and scoring schemes, the cutoff criteria, and the
final adjustments to the List. The Agency also requests comment on the
specific issues listed below. The Agency is not requesting comment on
the data or methodology used to develop the WMPT, or the scoring
results of the WMPT. The WMPT went through a thorough, comprehensive
and constructive public review and comment process. EPA has
incorporated its response to those comments in the underpinnings of
today's notice and therefore does not believe comments regarding the
WMPT are generally pertinent to this effort.
Specific issues for comment include:
1. Banned Chemicals
Is it appropriate to eliminate chemicals from consideration for the
draft RCRA PBT List because they are no longer used in production or
generated in hazardous waste, or are generated in very limited
quantities from very few production processes, and therefore are not
good candidates for future reductions through waste minimization? Is it
appropriate to eliminate banned pesticides, PCBs, and alkyl lead for
this reason, as the Agency has done in developing the List?
2. Waste Minimization Feasibility
Should the agency eliminate from consideration PBT chemicals
contained in hazardous waste for which there are few feasible waste
minimization options available, or should the agency consider these as
an incentive to encourage research and development of waste
minimization methods for these chemicals?
3. ``Non-measurable'' Chemicals
The draft RCRA PBT List includes 16 chemicals that were reported in
the National Hazardous Waste Constituent Survey but are not reported in
the Toxics Release Inventory, and therefore, cannot be easily tracked
over time. Is it appropriate to include on the List chemicals for that
TRI data, or other annual chemical-specific data, are not readily
available for tracking national chemical reduction progress? Are there
other reliable national sources of chemical reporting data that could
be used to track generation and reductions of these chemicals?
4. Chemicals With Very High P, B, and/or T Values
Should chemicals with very high data values for persistence,
bioaccumulation potential, human toxicity, and/or ecological toxicity
(e.g., with values at the top end of the data distributions) be
considered for addition to the RCRA PBT List, even though TRI data are
not available for tracking progress? How would progress be measured for
these chemicals?
5. Chemicals With Low Reported Quantities
Several chemicals on the RCRA PBT List are estimated in the
National Hazardous Waste Constituent Survey to be generated in
quantities of less than 100 pounds per year. The Agency did not use a
specific quantity cutoff in developing the RCRA PBT List. Should a
quantity cutoff be used? If so, what is the appropriate value for the
cutoff? Should different cutoffs be used for chemicals which are the
most toxic compared to others which are less toxic? If so, what should
those cutoffs be?
6. Priorities Identified by Other Organizations.
Should EPA add to the RCRA PBT List State or other organization's
priority chemicals which do not already appear on the List? Among these
chemicals, should those with low or no PBT scores (e.g., waste
solvents), or those with low or no chemical quantities (e.g., some
Level 1 U.S./Canada Binational Agreement chemicals) be included? A list
of chemical priorities identified by several States is located in RCRA
docket number F-98-MMLP-FFFFF.
7. Including Recycled Wastes in Determining Quantities of RCRA-Relevant
Waste Associated with Chemicals
In considering the quantity and prevalence of candidates for the
RCRA PBT List (step C.4 above), the Agency included quantities that
were recycled in its scoring procedure. Should recycled quantities be
included when determining the quantities of chemicals associated with
hazardous wastes in developing the RCRA PBT List, or should EPA measure
chemicals only at the point of generation?
Dated: October 30, 1998.
Elizabeth A. Cotsworth,
Acting Director, Office of Solid Waste.
[FR Doc. 98-29952 Filed 11-6-98; 8:45 am]
BILLING CODE 6560-50-P