[Federal Register Volume 66, Number 11 (Wednesday, January 17, 2001)]
[Rules and Regulations]
[Pages 4500-4547]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 01-1045]



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Part IX





Environmental Protection Agency





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40 CFR Part 372



Lead and Lead Compounds; Lowering of Reporting Thresholds; Community 
Right-to-Know Toxic Chemical Release Reporting; Final Rule

Federal Register / Vol. 66, No. 11 / Wednesday, January 17, 2001 / 
Rules and Regulations

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 372

[OPPTS-400140D; FRL-6722-4]
RIN 2070-AD38


Lead and Lead Compounds; Lowering of Reporting Thresholds; 
Community Right-to-Know Toxic Chemical Release Reporting

AGENCY: Environmental Protection Agency (EPA).

ACTION: Final rule.

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SUMMARY: EPA is lowering the reporting thresholds for lead and lead 
compounds which are subject to reporting under section 313 of the 
Emergency Planning and Community Right-to-Know Act of 1986 (EPCRA) and 
section 6607 of the Pollution Prevention Act of 1990 (PPA). The 
reporting thresholds are being lowered to 100 pounds. The lower 
reporting thresholds apply to lead and all lead compounds except for 
lead contained in stainless steel, brass, and bronze alloys. EPA is 
taking these actions pursuant to its authority under EPCRA section 
313(f)(2) to revise reporting thresholds. Today's actions also include 
modifications to certain reporting exemptions and requirements for lead 
and lead compounds.

DATES: This rule shall take effect on February 16, 2001; with the first 
reports at the lower thresholds due on or before July 1, 2002, for the 
2001 calendar year.

FOR FURTHER INFORMATION CONTACT: For technical information on this 
final rule contact: Daniel R. Bushman, Petitions Coordinator, 
Environmental Protection Agency, Mail Code 2844, 1200 Pennsylvania 
Ave., NW., Washington, DC 20460; telephone number 202-260-3882, e-mail 
address: <a href="/cdn-cgi/l/email-protection#244651574c49454a0a40454a4d4148644154450a434b52"><span class="__cf_email__" data-cfemail="afcddadcc7c2cec181cbcec1c6cac3efcadfce81c8c0d9">[email protected]</span></a>. For general information on EPCRA 
section 313, contact the Emergency Planning and Community Right-to-Know 
Hotline, Environmental Protection Agency, Mail Code 5101, 1200 
Pennsylvania Ave., NW., Washington, DC 20460, Toll free: 1-800-535-
0202, in Virginia and Alaska: 703-412-9877 or Toll free TDD: 1-800-553-
7672. Information concerning this action is also available on EPA's Web 
site at http://www.epa.gov/tri.

SUPPLEMENTARY INFORMATION:

I. General Information

A. Does this notice apply to me?

    You may be potentially affected by this action if you manufacture, 
process, or otherwise use lead or lead compounds. Potentially affected 
categories and entities may include, but are not limited to:

 
------------------------------------------------------------------------
                                      Examples of Potentially Affected
             Category                             Entities
------------------------------------------------------------------------
Industry                            SIC major group codes 10 (except
                                     1011, 1081, and 1094), 12 (except
                                     1241); or 20 through 39; or
                                     industry codes 4911 (limited to
                                     facilities that combust coal and/or
                                     oil for the purpose of generating
                                     power for distribution in
                                     commerce); or 4931 (limited to
                                     facilities that combust coal and/or
                                     oil for the purpose of generating
                                     power for distribution in
                                     commerce); or 4939 (limited to
                                     facilities that combust coal and/or
                                     oil for the purpose of generating
                                     power for distribution in
                                     commerce); or 4953 (limited to
                                     facilities regulated under the
                                     Resource Conservation and Recovery
                                     Act, subtitle C, 42 U.S.C. section
                                     6921 et seq.); or 5169; or 5171; or
                                     7389 (limited to facilities
                                     primarily engaged in solvent
                                     recovery services on a contract or
                                     fee basis)
------------------------------------------------------------------------
Federal Government                  Federal facilities
------------------------------------------------------------------------

    This table is not intended to be exhaustive, but rather provides a 
guide for readers regarding entities likely to be affected by this 
action. Other types of entities not listed in the table could also be 
affected. To determine whether your facility would be affected by this 
action, you should carefully examine the applicability criteria in part 
372 subpart B of Title 40 of the Code of Federal Regulations. If you 
have questions regarding the applicability of this action to a 
particular entity, consult the person listed in the preceding of FOR 
FURTHER INFORMATION CONTACT section.

B. How can I get additional information or copies of this document or 
other support documents?

    1. Electronically. You may obtain electronic copies of this 
document from the EPA internet Home Page at http://www.epa.gov/. On the 
Home Page select ``Laws and Regulations'' and then look up the entry 
for this document under the ``Federal Register--Environmental 
Documents.'' You can also go directly to the ``Federal Register'' 
listings at http://www.epa.gov/fedrgstr/.
    2. In person. The Agency has established an official record for 
this action under docket control number OPPTS-400140. The official 
record consists of the documents specifically referenced in this 
action, any public comments received during an applicable comment 
period, and other information related to this action, including any 
information claimed as confidential business information (CBI). This 
official record includes the documents that are physically located in 
the docket, as well as the documents that are referenced in those 
documents. The public version of the official record does not include 
any information claimed as CBI. The public version of the official 
record, which includes printed, paper versions of any electronic 
comments submitted during an applicable comment period, is available 
for inspection in the TSCA Nonconfidential Information Center, North 
East Mall Rm. B-607, Waterside Mall, 401 M St., SW., Washington, DC. 
The Center is open from noon to 4 p.m., Monday through Friday, 
excluding legal holidays. The telephone number of the Center is (202) 
260-7099.

II. What is EPA's Statutory Authority for Taking These Actions?

    EPA is finalizing these actions under sections 313(f)(2), 313(g), 
313(h), and 328 of EPCRA, 42 U.S.C. 11023(f)(2), 11023(g), 11023(h), 
and 11048; and section 6607 of PPA, 42 U.S.C. 13106. Section 313 of 
EPCRA requires certain facilities manufacturing, processing, or 
otherwise using a listed toxic chemical in amounts above reporting 
threshold levels, to report certain facility specific information about 
such chemicals, including the annual releases and other quantities 
entering each environmental medium. These reports must be filed by July 
1 of each year for the previous calendar year. Such facilities also 
must report recycling and other waste management data and source 
reduction activities for such chemicals, pursuant to section 6607 of 
PPA.

A. What is EPA's Statutory Authority To Lower EPCRA Reporting 
Thresholds?

    EPA is finalizing these actions pursuant to its authority under 
EPCRA section 313(f)(2) to revise reporting thresholds. EPCRA section 
313

[[Page 4501]]

establishes default reporting thresholds, which are set forth in 
section 313(f)(1). Section 313(f)(2), however, provides that EPA:
    may establish a threshold amount for a toxic chemical different 
from the amount established by paragraph (1). Such revised threshold 
shall obtain reporting on a substantial majority of total releases 
of the chemical at all facilities subject to the requirements of 
this section. The amounts established by EPA may, at the 
Administrator's discretion, be based on classes of chemicals or 
categories of facilities.
    This provision provides EPA with broad, but not unlimited, 
authority to establish thresholds for particular chemicals, classes of 
chemicals, or categories of facilities, and commits to EPA's discretion 
the determination that a different threshold is warranted. Congress 
also committed the determination of the levels at which to establish 
any alternate thresholds to EPA's discretion, requiring only that any 
``revised threshold shall obtain reporting on a substantial majority of 
total releases of the chemical at all facilities subject to the 
requirements'' of section 313. 42 U.S.C. 11023(f)(2).
    For purposes of determining what constitutes a ``substantial 
majority of total releases,'' EPA interprets the language in section 
313(f)(2), ``facilities subject to the requirements of [section 313],'' 
to refer to those facilities that fall within the category of 
facilities described by sections 313 (a) and (b), i.e., the facilities 
currently reporting. Subsection (a) lays out the general requirement 
that ``the owner or operator of facilities subject to the requirements 
of this section shall'' file a report under EPCRA section 313. 
Subsection (b) then defines the facilities subject to the requirements 
of this section:
    [t]he requirements of this section shall apply to owners and 
operators of facilities that have 10 or more full-time employees and 
that are in Standard Industrial Classification Codes 20-39, . . . 
and that manufactured, processed, or otherwise used a toxic chemical 
listed under subsection (c) of this section in excess of the 
quantity of that toxic chemical established under subsection (f) of 
this section during the calendar year for which a toxic chemical 
release form is required under this section.
    Thus, in revising the reporting thresholds, EPA must ensure that, 
under the new thresholds, a substantial majority of releases currently 
being reported will continue to be reported. No further prerequisites 
for exercising this authority appears in the statute.

B. What is EPA's Statutory Authority for Making Modifications to Other 
EPCRA section 313 Reporting Requirements?

    Today's actions also include modifications to certain reporting 
exemptions and requirements for lead and lead compounds. Congress 
granted EPA rulemaking authority to allow the Agency to fully implement 
the statute. EPCRA section 328 provides that the ``Administrator may 
prescribe such regulations as may be necessary to carry out this 
chapter'' (28 U.S.C. 11048).

III. Background Information

A. What is the General Background for this Action?

    Under EPCRA section 313, Congress set the initial parameters of the 
Toxics Release Inventory (TRI), but also gave EPA clear authority to 
modify reporting in various ways, including authority to change the 
toxic chemicals subject to reporting, the facilities required to 
report, and the threshold quantities that trigger reporting. By 
providing this authority, Congress recognized that the TRI program 
would need to evolve to meet the needs of a better informed public and 
to refine existing information. EPA has, therefore, undertaken a number 
of actions to expand and enhance TRI. These actions include expanding 
the number of reportable toxic chemicals by adding 286 toxic chemicals 
and chemical categories to the EPCRA section 313 list in 1994. Further, 
a new category of facilities was added to EPCRA section 313 on August 
3, 1993, through Executive Order 12856, which requires Federal 
facilities meeting threshold requirements to file annual EPCRA section 
313 reports. In addition, in 1997 EPA expanded the number of private 
sector facilities that are required to report under EPCRA section 313 
by adding seven new industrial groups to the list of covered 
facilities. At the same time, EPA has sought to reduce the burden of 
EPCRA section 313 reporting by actions such as delisting chemicals it 
has determined do not meet the statutory listing criteria and 
establishing an alternate reporting threshold of 1 million pounds for 
facilities with 500 pounds or less of production-related releases and 
other wastes. Facilities meeting the requirements of this alternate 
threshold may file a certification statement (Form A) instead of 
reporting on the standard EPCRA section 313 form, the Form R.
    On October 29, 1999 (64 FR 58666), EPA finalized enhanced reporting 
requirements that focused on a unique group of toxic chemicals that 
persist and bioaccumulate in the environment. These chemicals are 
commonly referred to as persistent bioaccumulative toxic chemicals or 
PBT chemicals. Until that action, with the exception of the alternate 
threshold certification on Form A, EPA had not altered the statutory 
reporting threshold for any listed chemicals. However, as the TRI 
program has evolved over time and as communities identify areas of 
special concern, thresholds and other aspects of the EPCRA section 313 
reporting requirements may need to be modified to assure the collection 
and dissemination of relevant, topical information and data. Toxic 
chemicals that persist and bioaccumulate are of particular concern 
because they remain in the environment for significant periods of time 
and concentrate in the organisms exposed to them. The October 29, 1999, 
PBT chemical final rule set forth criteria to be used by the EPCRA 
section 313 program for evaluating whether a listed toxic chemical 
persists or bioaccumulates in the environment. EPA has evaluated lead 
and lead compounds using these criteria, and has concluded that lead 
and lead compounds are PBT chemicals. Thus, as with the PBT chemical 
final rule, today's action further increases the utility of TRI to the 
public by lowering the reporting thresholds for lead and lead 
compounds. Lowering the reporting thresholds for lead and lead 
compounds will ensure that the public has important information on the 
quantities of these chemicals released or otherwise managed as waste, 
that would not be reported under the 10,000 and 25,000 pound/year 
thresholds that apply to most other listed toxic chemicals.

B. What Outreach Has EPA Conducted?

    EPA has engaged in a comprehensive outreach effort relating to this 
action. This outreach served to inform interested parties, including 
industries and small businesses affected by the rule, state regulatory 
officials, environmental organizations, labor unions, community groups, 
and the general public of EPA's intention to lower the applicable EPCRA 
section 313 reporting thresholds for lead and lead compounds. EPA held 
three public meetings (in Los Angeles, CA (November 30, 1999); Chicago, 
IL (December 2, 1999); and Washington, DC (December 14, 1999)) during 
the comment period for the proposal. Participants included a range of 
industry representatives, trade associations (representing both small 
and large businesses), law firms representing industry groups, 
environmental groups, the general public, plus other groups and 
organizations. For state and tribal governments, EPA attended the 
regularly-held public meetings of the Forum on State and Tribal Toxics

[[Page 4502]]

Action (FOSTTA) to discuss the proposed rule. EPA also received 
substantial public comment on the proposed rule, to which EPA is 
responding in this Final Rule and the Response to Comments document 
(Ref. 1). In response to the strong interest in the proposed rule, and 
to allow more individuals and groups to submit their comments, EPA 
extended the public comment period. The comment period was first 
extended from September 17 to November 1, 1999 (at 64 FR 51091, 
September 21, 1999) (FRL-6382-9) and then again from November 1 to 
December 16, 1999 (at 64 FR 58370, October 29, 1999) (FRL-6391-8) to 
allow commenters time to supplement or revise their comments in light 
of the decisions made in the final PBT chemical rulemaking (64 FR 
58666). Additional information regarding EPA's outreach may be found in 
supporting documents included in the public version of the official 
record.

IV. Summary of Proposal

A. What Persistence and Environmental Fate Data were Presented for Lead 
and Lead Compounds?

    A chemical's persistence refers to the length of time the chemical 
can exist in the environment before being destroyed (i.e., transformed) 
by natural processes. The environmental media for which persistence is 
measured or estimated include air, water, soil, and sediment; however, 
water is the medium for which persistence values are most frequently 
available. It is important to distinguish between persistence in a 
single medium (air, water, soil, or sediment) and overall environmental 
persistence. Persistence in an individual medium is controlled by 
transport of the chemical to other media, as well as transformation to 
other chemical species. Persistence in the environment as a whole is a 
distinct concept. It is based on the observations that the environment 
behaves as a set of interconnected media, and that a chemical substance 
released to the environment will become distributed in these media in 
accordance with the chemical's intrinsic (physical/chemical) properties 
and reactivity. For overall persistence, only irreversible 
transformation contributes to net loss of a chemical substance.
    Although metals and metal compounds, including lead and lead 
compounds, may be converted from the metal to a metal compound or from 
one metal compound to another in the environment, the metal cannot be 
destroyed. Thus, metals are obviously persistent in the environment in 
some form. The form of the metal that exists in the environment depends 
on its environmental fate. Environmental fate refers to the ultimate 
result of physical, chemical, and biological processes acting upon a 
metal or metal compound once it is released into the environment. The 
environmental fate determines the extent to which the metal or the 
metal from a metal compound will be available for exposure to organisms 
once released into the environment. The environmental fate of a metal 
or metal compound varies depending on the environmental conditions and 
the physical/chemical properties of the metal in question.
    The information summarized in the proposed rule for the 
environmental fate of lead in each environmental medium represented the 
key elements influencing the transport, transformation, and 
bioavailability of lead in air, soil, water and sediments. This 
information, as well as a more extensive review of the existing data on 
the environmental fate of lead are contained in The Environmental Fate 
of Lead and Lead Compounds (Ref. 2) and in the references contained 
therein. Based on this information, EPA concluded that processes 
commonly observed in the environment can result in the release of 
available (ionic) lead where it can be bioaccumulated by organisms. 
These processes may occur in soil and aquatic environments with low pH 
and low levels of clay and organic matter. Under these conditions, the 
solubility of lead is enhanced and if there are no sorbing surfaces and 
colloids, lead ion can remain in solution for a sufficient period to be 
taken up by biota. Lead sorption to soil organic matter has been shown 
to be pH dependent. Decreasing pH can lead to increasing concentrations 
of lead in soil water; while increasing pH can lead to decreasing 
concentrations of lead in soil water.
    The Agency's analysis of the environmental fate of lead and lead 
compounds showed that under many environmental conditions lead is 
available to express its toxicity and to bioaccumulate. In the EPCRA 
section 313 program, the issue of the environmental availability of 
metals from metal compounds is broader than just its implications for 
whether a chemical is a PBT. The issue of both the environmental 
availability and bioavailability has been addressed for EPCRA section 
313 chemical assessments through EPA's policy and guidance concerning 
petitions to delist individual members of the metal compound categories 
listed under EPCRA section 313 (May 23, 1991, 56 FR 23703). This policy 
states that if the metal in a metal compound cannot become available as 
a result of biotic or abiotic processes then the metal will not be 
available to express its toxicity. If the intact metal compound is not 
toxic and the metal is not available from the metal compound then such 
a chemical is a potential candidate for delisting from the EPCRA 
section 313 list of toxic chemicals. EPA developed this petition policy 
specifically to address such circumstances.

B. What Aquatic Bioaccumulation Data was Presented for Lead and Lead 
Compounds?

    Bioaccumulation is a general term that is used to describe the 
process by which organisms may accumulate chemical substances in their 
bodies. The term bioaccumulation refers to uptake of chemicals by 
organisms both directly from water and through their diet (Ref. 3). EPA 
has defined bioaccumulation as the net accumulation of a substance by 
an organism as a result of uptake from all environmental sources (60 FR 
15366). The nondietary accumulation of chemicals in aquatic organisms 
is referred to as bioconcentration, and may be described as the process 
through which a chemical is distributed between the organism and 
environment based on the chemical's properties, environmental 
conditions, and biological factors such as an organism's ability to 
metabolize the chemical (Ref. 4). EPA has defined bioconcentration as 
the net accumulation of a substance by an aquatic organism as a result 
of uptake directly from the ambient water through gill membranes or 
other external body surfaces (60 FR 15366). A chemical's potential to 
bioaccumulate can be quantified by measuring or predicting the 
chemical's bioaccumulation factor (BAF). EPA has defined the BAF as the 
ratio of a substance's concentration in tissue of an aquatic organism 
to its concentration in the ambient water, in situations where both the 
organism and its food are exposed and the ratio does not change 
substantially over time (60 FR 15366). A chemical's potential to 
bioaccumulate can also be quantified by measuring or predicting the 
chemical's bioconcentration factor (BCF). EPA has defined the BCF as 
the ratio of a substance's concentration in tissue of an aquatic 
organism to its concentration in the ambient water, in situations where 
the organism is exposed through water only and the ratio does not 
change substantially over time (60 FR 15366).
    A review of the ecotoxicological literature indicates that 
bioconcentration values of lead and certain lead compounds ( lead 
salts) in aquatic plants and animals are often

[[Page 4503]]

above a bioconcentration/bioaccumulation factor of 1,000 and in some 
species at or greater than 5,000. Lead is bioaccumulated by aquatic 
organisms such as plants, bacteria, invertebrates, and fish. The 
principle form that is believed to be accumulated is divalent lead 
(i.e., lead in its plus 2 oxidation state (Pb +2 )). It has been shown 
that fish held in water at a pH of 6.0 accumulate three times as much 
lead as fish held in water at a pH of 7.5 (Ref. 5), thus as pH 
decreases the availability of divalent lead increases. Older organisms 
usually have the highest body burdens, and lead accumulates in bony 
tissues to the greatest extent.
    The bioaccumulation data reviewed concerning the extent (magnitude) 
of lead bioaccumulation found to occur in many aquatic plants and 
animals and the lead bioconcentration factors (BCF) determined or 
measured from laboratory studies conducted for certain durations using 
BCF test methods, can be found in the bioaccumulation support document 
(Ref. 6). Concentrations of lead monitored in various organisms were 
determined by comparing concentrations in the environment (water) with 
concentrations measured in the organisms. In general, bioconcentration 
values for four freshwater invertebrate species ranged from 499 to 
1,700 (Ref. 7). BCFs for two species of freshwater fish were much 
lower, 42 and 45. However, certain fish tissues have much higher BCF 
values, e.g., the BCF value for the intestinal lipids in rainbow trout 
were as high as 17,300. Freshwater phytoplankton and both marine and 
freshwater algae accumulate or concentrate lead to very high levels 
(e.g., greater than 10,000x). BCF values for marine bivalve organisms 
were as high as 4,985 for blue mussels. Eastern oysters also had BCF 
values greater than 1,000. These data indicate that many of the BCF 
values and measured environmental concentration factors for lead are 
above 1,000 with several species having BCF or observed concentration 
factors at or above 5,000. The references cited for blue mussels 
include a range of values, the upper end of which is essentially 5,000 
(i.e., 4,985). There are also a few fish tissues that have BCFs greater 
than 10,000, though most of the available fish data are below 5,000.

C. What Human Bioaccumulation Data was Presented for Lead and Lead 
Compounds?

    There is a great deal of information available on the 
bioaccumulation of lead in humans and the effects that such 
accumulation can have (Refs. 8, 9, 10, and 11). The bioaccumulation of 
lead in humans is well documented. Although lead has no known 
biological function in humans, it is readily absorbed through the gut 
and can be absorbed by inhalation and, to some extent by dermal 
contact. Absorption of lead can occur as a result of exposure to air-
borne forms of lead, as well as ingestion or contact with contaminated 
soil and dust. Children and developing fetuses are known to absorb lead 
more readily than adults and to excrete it at a lower total rate. These 
findings are especially significant since young children are most 
susceptible to the adverse effects associated with lead exposure. Lead 
absorption varies from very low levels (e.g., 5%) up to essentially 
100%. Lead absorption appears to be linked to particle size, the 
chemical composition, and other factors (Refs. 12 and 13). Long-lasting 
impacts on intelligence, motor control, hearing, and neurobehavioral 
development of children have been documented at levels of lead that are 
not associated with clinical intoxication and were once thought to be 
safe. An analysis of human blood-lead level data collected from the 
most recent publicly available National Health and Nutrition 
Examination Surveys (see Ref. 9), showed that approximately 4.4% of the 
nation's children aged 1-5 years have blood-lead concentrations at or 
above 10 micrograms per deciliter (mg/ dL), which is the current action 
level established by the Centers for Disease Control. While this is a 
significant improvement over the 88% of children who had blood lead 
levels above this threshold in 1976, before the phase-out of lead in 
gasoline, it is still cause for concern because it indicates that 
nearly 900,000 children aged 1-5 have unacceptably high blood-lead 
levels.
    Once lead is absorbed in the body, it is primarily distributed to 
the blood, soft tissues (kidney, bone marrow, liver, and brain) and to 
the mineralizing tissue (bones and teeth). In one study it was shown 
that in adults, following a single dose of lead, one-half of the lead 
absorbed from the original exposure remained in the blood for 
approximately 25 days after exposure, in soft tissues for about 40 
days, and in bone for more than 25 years (Ref. 14). Once in the bone, 
lead can re-enter the blood and soft tissues. Under certain 
circumstances, such as pregnancy and lactation, lead can more readily 
re-enter blood and soft tissues. Thus, accumulation of lead in bone can 
serve to maintain elevated blood lead levels years after exposure. The 
total amount of lead in long-term bone retention can approach 200 mg 
for adult males 60-70 years old (and even higher with occupational 
exposure). For adults, up to 94% of the total amount of lead in the 
body is contained in the bones and teeth but for children only about 
73% is stored in their bones. While the increase in bone lead level 
across childhood may appear modest, the total accumulation rate is 
actually 80-fold. The increase is 80-fold because children undergo a 
40-fold increase in skeletal mass. While lead absorption rates are 
influenced by several parameters, including route of exposure, chemical 
speciation, the physical/chemical characteristics of the lead and the 
exposure medium, as well as the age and physiological states of the 
exposed individual, there is substantial documentation that a 
significant amount of lead can be absorbed and accumulated in humans. 
Such absorbed and accumulated lead can cause significant deleterious 
health effects, particularly in children.

D. What Proposed Conclusions did EPA Reach from Its Proposal Review of 
the Available Data on Lead and Lead Compounds?

    EPA's review of the available information on lead and lead 
compounds led EPA to conclude that lead and lead compounds are highly 
persistent and at the least, bioaccumulative. The persistence of lead 
in the environment is not in question since, as a metal, lead cannot be 
destroyed in the environment. With respect to whether lead or lead 
compounds released to the environment will result in lead that is 
available, the data indicate that under many environmental conditions 
lead does become available. The conclusion that lead is available in 
the environment is confirmed by the data on the bioaccumulation of lead 
in aquatic organisms and in humans as a result of environmental 
exposures. As for lead's bioaccumulation potential, lead has been shown 
to bioaccumulate in laboratory studies, has been found to bioaccumulate 
in organisms observed in the environment, and has been found to 
bioaccumulate in humans. EPA noted in its proposal that these data 
indicate that many of the BCF values and measured environmental 
concentration factors for lead are above 1,000 with several species 
having BCF or observed concentration factors at or above 5,000. The 
references cited for blue mussels include a range of values, the upper 
end of which is essentially 5,000 (i.e., 4,985). In addition, EPA 
explained that ``[t]he bioaccumulation and persistence of lead in 
humans is well documented'' and requested comment on how such

[[Page 4504]]

data should be regarded in classifying lead and lead compounds as 
highly bioaccumulative.
    A high concern for the bioaccumulation potential for chemicals with 
BCF values above 1,000 is consistent with the discussion of BCF values 
in the proposed rule on PBT chemicals (January 5, 1999, 64 FR 688). In 
addition, there is considerable information on the accumulation of lead 
in humans, including children, who are the most susceptible to the 
toxic effects of lead. The data on lead's persistence and availability 
in the environment, the observed high bioaccumulation values in aquatic 
organisms, and lead's ability to accumulate in humans, provided the 
basis for EPA preliminarily concluding that lead and lead compounds are 
highly persistent and highly bioaccumulative.

E. What Changes to the Reporting Thresholds did EPA Propose for Lead 
and Lead Compounds?

    In evaluating potential lower reporting thresholds for lead and 
lead compounds, EPA considered not only their persistence and 
bioaccumulation properties and the purposes of EPCRA section 313, but 
also the potential burden that might be imposed on the regulated 
community. Because PBT chemicals, including lead and lead compounds, 
persist and bioaccumulate in the environment, they have the potential 
to pose greater exposure to humans and the environment over a longer 
period of time. The nature of PBT chemicals, including lead and lead 
compounds, indicates that small quantities of such chemicals are of 
concern, which provides strong support for setting lower reporting 
thresholds than the current section 313 thresholds of 10,000 and 25,000 
pounds. For determining how low reporting thresholds should be set for 
PBT chemicals, including lead and lead compounds, EPA adopted a two-
tiered approach. Thus, EPA made a distinction between persistent 
bioaccumulative toxic chemicals and that subset of PBT chemicals that 
are highly persistent and highly bioaccumulative by setting lower 
reporting thresholds based on two levels of concern. As explained in 
the final PBT rule and in the proposed lead rule, this approach 
identifies as PBT chemicals those that are persistent (i.e., with half-
lifes of at least 2 months) and those that are bioaccumulative (i.e., 
based on aquatic studies showing BAF/BCF values of at least 1,000 and/
or human data showing evidence of bioaccumulation). Further, as also 
explained in the PBT rule and the proposed lead rule, highly PBT 
chemicals are identified as those that are highly persistent (i.e., 
with half-lifes of 6 months or greater) and those that are highly 
bioaccumulative (e.g., BAF/BCF values of 5,000 or greater). EPA 
preliminarily concluded that lead and lead compounds to be highly 
persistent and highly bioaccumulative toxic chemicals.
    In determining the appropriate reporting thresholds to propose for 
lead and lead compounds, EPA started with the premise that low or very 
low reporting thresholds may be appropriate for these chemicals based 
on their persistence and bioaccumulation potentials only. EPA then 
considered the burden that would be imposed by lower reporting 
thresholds and the distribution of reporting across covered facilities. 
Using this approach and considering the factors described above and the 
purposes of EPCRA section 313, EPA proposed to lower the manufacture, 
process, and otherwise use thresholds to 10 pounds for lead and lead 
compounds. For purposes of section 313 reporting, threshold 
determinations for chemical categories, including lead compounds, are 
based on the total of all toxic chemicals in the category (see 40 CFR 
372.25(d)).

F. What Other Reporting Issues Did EPA Consider for Lead and Lead 
Compounds?

    1. De minimis exemption. In 1988, EPA promulgated the de minimis 
exemption because: (1) The Agency believed that facilities newly 
covered by EPCRA section 313 would have limited access to information 
regarding low concentrations of toxic chemicals in mixtures that are 
imported, processed, otherwise used or manufactured as impurities; (2) 
the Agency did not believe that these low concentrations would result 
in quantities that would significantly contribute to threshold 
determinations and release calculations at the facility (53 FR 4509, 
February 16, 1988); and (3) the exemption was consistent with 
information required by the Occupational Safety and Health 
Administration's (OSHA) Hazard Communication Standard (HCS). However, 
given that: (1) Covered facilities currently have several sources of 
information available to them regarding the concentration of PBT 
chemicals in mixtures; (2) even minimal releases of persistent 
bioaccumulative toxic chemicals may result in significant adverse 
effects and can reasonably be expected to significantly contribute to 
exceeding the proposed lower thresholds; and (3) the concentration 
levels chosen, in part, to be consistent with the OSHA HCS are 
inappropriately high for PBT chemicals, EPA's original rationale for 
the de minimis exemption does not apply to PBT chemicals. EPA therefore 
proposed to eliminate the de minimis exemption for lead and lead 
compounds based on their status as PBT chemicals. EPA did not propose, 
however, to modify the applicability of the de minimis exemption to the 
supplier notification requirements (40 CFR 372.45(d)(1)) because the 
Agency believed there was sufficient information available.
    2. Use of the Alternative threshold and Form A. EPA stated its 
belief that use of the existing alternate threshold and reportable 
quantity for Form A would be inconsistent with the intent of expanded 
reporting for PBT chemicals such as lead and lead compounds. The 
general information provided in the Form A on the quantities of the 
chemical that the facility manages as waste is insufficient for 
conducting analyses on PBT chemicals and would be virtually useless for 
communities interested in assessing risk from releases and other waste 
management of PBT chemicals. EPA, therefore, proposed excluding lead 
and lead compounds from the alternate threshold of 1 million pounds.
    3. Proposed changes to the use of range reporting. EPA stated its 
belief that use of ranges could misrepresent data accuracy for lead and 
lead compounds because the low or the high end range numbers may not 
really be that close to the estimated value, even taking into account 
any inherent error in reporting (i.e., errors in measurements and 
developing estimates). EPA believed this uncertainty would severely 
limit the applicability of release information where the majority of a 
facility's releases are within the amounts eligible for range 
reporting. Given EPA's belief that the large uncertainty that would be 
part of these data would severely limit their utility, EPA proposed to 
eliminate range reporting for lead and lead compounds.
    4. Proposed changes to the use of the half-pound rule and whole 
numbers. EPA currently allows facilities to report whole numbers and to 
round releases of 0.5 pound or less to zero when reporting on EPCRA 
section 313 listed chemicals not designated as PBT chemicals in the 
October 29, 1999 final rule. EPA explained its concern that the 
combination of requiring the reporting of whole numbers and allowing 
rounding to zero would result in a significant number of facilities 
reporting their releases of lead and lead compounds as zero. EPA, 
therefore, proposed that all releases or other waste management 
quantities greater than \1/10\

[[Page 4505]]

of a pound of lead and lead compounds be reported, provided that the 
appropriate activity threshold has been exceeded.
    5. Proposed exemption for the reporting of lead in certain alloys. 
In the proposal, EPA proposed to defer making a final decision on lower 
reporting thresholds for lead contained in stainless steel, brass, and 
bronze alloys until the Agency could complete an ongoing scientific 
review of issues pertinent to the reporting of these types of alloys. 
This would result in no changes to the reporting requirements for lead 
contained in stainless steel, brass, and bronze alloys until EPA makes 
a final determination on whether there should be any changes to the 
reporting requirements for lead and other metals contained in these 
three types of alloys. EPA, therefore, proposed to include a qualifier 
to the listing for lead in 40 CFR 372.28. This qualifier would read 
``this lower threshold does not apply to lead when contained in a 
stainless steel, brass, or bronze alloy.''

V. Summary of the Final Rule

A. What Threshold Has EPA Established for Lead and Lead Compounds?

    EPA is finalizing manufacture, process, and otherwise use 
thresholds of 100 pounds for lead and lead compounds, with the first 
reports at this lower threshold due on or before July 1, 2002, for the 
2001 calendar year. This lower reporting threshold does not apply to 
lead contained in stainless steel, brass, and bronze alloys nor do any 
of the other changes discussed below in Unit V.B. However, lead 
contained in stainless steel, brass, and bronze alloys remains 
reportable under the 25,000 pound manufacture and process reporting 
threshold and the 10,000 pound otherwise use reporting threshold.

B. What Exemptions and Other Reporting Issues is EPA Addressing for 
Lead and Lead Compounds?

    EPA is eliminating the de minimis exemption for lead and lead 
compounds. However, this action will not affect the applicability of 
the de minimis exemption to the supplier notification requirements (40 
CFR 372.45(d)(1)). In today's action, EPA is also excluding lead and 
lead compounds from eligibility for the alternate threshold of 1 
million pounds and eliminating range reporting for on-site releases and 
transfers off-site for further waste management for lead and lead 
compounds. This will not affect the applicability of the range 
reporting of the maximum amount on-site as required by EPCRA section 
313(g). EPA proposed to require reporting of all releases and other 
waste management quantities greater than \1/10\ of a pound of lead and 
lead compounds. Also, EPA proposed that releases and other waste 
management quantities would continue to be reported to two significant 
digits. In addition, EPA proposed that for quantities of 10 pounds or 
greater, only whole numbers would be required to be reported. After 
reviewing all the comments on this issue, EPA is providing additional 
guidance on the level of precision at which facilities should report 
their releases and other waste management quantities of lead and lead 
compounds. Facilities should still report releases and other waste 
management quantities greater than 0.1 pound provided the accuracy and 
the underlying data on which the estimate is based supports this level 
of precision. Rather than reporting in whole numbers and to two 
significant digits, if a facility's release or other waste management 
estimates support reporting an amount that is more precise than whole 
numbers and two significant digits, then the facility should report 
that more precise amount. The Agency believes that, particularly for 
PBT chemicals such as lead and lead compounds, facilities may be able 
to calculate their estimates of releases and other waste management 
quantities to \1/10\ of a pound and believes that such guidance is 
consistent with the reporting requirements of sections 313(g) and (h).

VI. Summary of Public Comments and EPA Responses

A. How is EPA Responding to Comments Relating to Generic Issues?

    EPA received numerous comments relating to the generic issues 
raised and resolved in the first rulemaking on PBT chemicals, published 
on October 29, 1999 (64 FR 58666); for example, whether the Agency 
should select lower thresholds based on a risk assessment. Some 
commenters merely reiterate comments raised in the previous rulemaking. 
Other commenters rephrase, in terms of lead and lead compounds, 
comments that have been previously submitted on these generic issues, 
without presenting additional information or concerns specific to lead 
and lead compounds.
    In its proposal to lower the thresholds for lead and lead 
compounds, EPA explicitly limited its request for comments to issues 
specific to lead and lead compounds, such as whether lead and lead 
compounds meet the EPCRA section 313 persistence and bioaccumulation 
criteria articulated in the PBT rule and proposed lead rule, and 
whether lead and lead compounds present such unique technical or policy 
issues that they merit different treatment than that established for 
either the class of PBT chemicals or the subset of highly persistent 
and highly bioaccumulative toxic chemicals (see 64 FR 42224 and 58666). 
Notwithstanding that EPA extended the comment period on this rulemaking 
to allow for an additional 48 days following publication of the final 
PBT chemical rule, commenters failed to present issues or information 
that persuades the Agency to revisit the decisions made with respect to 
generic issues in the PBT chemical rule, or that provides any basis for 
treating lead and lead compounds separately from how the Agency 
generally approachs PBT chemicals within the EPCRA section 313 program.
    To the extent that commenters provide comments on the generic 
issues that were specific to lead and lead compounds, these comments 
are addressed in this preamble and in the Response to Comments (RTC) 
document for this final rule (Ref. 1). For responses to those comments 
on the generic issues that were not specific to lead and lead compounds 
the reader is referred to the PBT chemical final rule (64 FR 58666) and 
the associated Response to Comments document (Ref. 15). The remainder 
of this Unit contains responses to major comments on the issues of the 
EPCRA section 313 reporting thresholds for lead and lead compounds, the 
technical information regarding the persistence and bioaccumulation 
potential of lead and lead compounds, and the alloys reporting 
limitation for lead. Responses to major comments on EPA's economics 
analysis (Ref. 16) and regulatory assessment determinations are 
contained in Units VII and IX respectively. Additional responses to 
comments not addressed in this preamble are contained in the RTC 
document for this final rule (Ref. 1).

B. What Comments did EPA Receive on its Statutory Authority to Lower 
Reporting Thresholds for Lead and Lead Compounds?

    Several commenters allege that under EPA's interpretation of EPCRA 
section 313(f)(2), Congress did not provide an ``intelligible 
principle'' for determining whether or how much to lower a statutory 
threshold, thereby rendering this provision unconstitutional as an 
improperly broad delegation of legislative power. The commenters raise 
several points in support of this contention; several commenters cite

[[Page 4506]]

EPA's statement in the proposal that ``Congress provided no 
prerequisites to the exercise of EPA's authority to lower [EPCRA 
section 313] thresholds'' to demonstrate that EPA does not have the 
authority to lower the thresholds without violating the non-delegation 
doctrine. Other commenters support this allegation merely by reference 
to the fact that EPCRA section 313(f)(2) does not prohibit the Agency 
from establishing a threshold of ``0.'' Another commenter contends that 
the unconstitutional delegation of authority is even more striking than 
it was in section 109(b)(1) of the Clean Air Act, which at least 
provided the Agency with the direction to set standards ``requisite to 
protect the public health'' and ``with an adequate margin of safety.'' 
EPCRA, the commenter states, sets forth no standard for establishing 
reduced reporting thresholds. To support their assertions, several of 
these commenters specifically cite the decision in American Trucking 
Association v. EPA, 175 F.3d 1027 (D.C. Circuit, 1999) cert. granted 
sub nom. Browner v. American Trucking Association, 120 S.Ct 2003 (US 
May 22, 2000)(No. 99-1247).
    EPA disagrees. As a preliminary matter, EPA disagrees with the 
interpretation of the non-delegation doctrine articulated in American 
Trucking, and has appealed that decision to the Supreme Court. 
Nonetheless, EPA believes that Congress has provided an ``intelligible 
principle'' sufficient for the delegation of authority contained in 
EPCRA section 313(f)(2).
    The commenters appear to have fundamentally misunderstood EPA's 
explanation of its rationale for selecting the specific thresholds 
adopted in the final PBT chemical rule, and the implications these 
actions had for the selection of the thresholds for lead and lead 
compounds. As part of the discussion in the final PBT chemical rule, 
EPA noted that for several reasons, it was establishing ``two sets of 
revised thresholds based on two classes of PBT chemicals,'' and stated 
its intention that ``the revised thresholds establish a set of 
categories that would be generally applicable to future designated PBT 
chemicals.'' (64 FR 58689). Thus, the selection of the specific 
threshold for lead and lead compounds is governed by the analyses laid 
out in EPA's preamble to the final PBT chemical rule and in the 
proposed lead rule. See also EPA's rationale for the specific threshold 
chosen for lead and lead compounds, infra at Unit VI.E. Under this 
construct, taking into account the aquatic and human data available.
    In the preamble to the final PBT chemical rule, and the associated 
Response to Comments Document (Ref. 15) , EPA described at length the 
process by which it distilled Congressional guidance from various 
sources, such as the language and legislative history of EPCRA sections 
313(f)(2) and (h), to guide its exercise of discretion in lowering the 
thresholds. See (e.g., (64 FR 58687-692). Specifically, EPA explained:
    EPA relied on the language of EPCRA sections 313(f)(2) and (h), and 
the legislative history, to elicit the following principles to guide 
its exercise of discretion in lowering the thresholds, and in selecting 
the specific thresholds: (1) The purposes of EPCRA section 313; (2) the 
``verifiable, historical data'' that convinces EPA of the need to lower 
the thresholds; (3) the chemical properties shared by the members of 
the class of toxic chemicals for which EPA is lowering the thresholds 
(i.e., the degree of persistence and bioaccumulation); and (4) the 
reporting burden imposed by revised thresholds to the extent that such 
consideration would not deny the public significant information from a 
range of covered industry sectors. Further, EPA believes that in the 
language of EPCRA Sec. 313, and its legislative history, Congress 
provided direction on the appropriate weight to allocate to each of 
these considerations in implementing EPCRA section 313(f)(2). These 
considerations underlay the entire process by which EPA determined the 
appropriate thresholds. But the Agency's choice of revised thresholds 
was governed, and ultimately constrained, by EPCRA section 313's 
overriding purpose, which is to provide government agencies, 
researchers, and local communities, with a comprehensive picture of 
toxic chemical releases and potential exposures to humans and 
ecosystems. Id. at 58687.
    EPA also disagrees with the analyses on which the commenters rely 
to support their assertions that Congress provided no intelligible 
principle to guide EPA's delegated authority under EPCRA section 
313(f)(2). Whether the legislative guidance offered sufficiently 
constrains the discretion delegated to the Agency under EPCRA section 
313(f)(2) must be evaluated against the actual ``power to roam'' that 
this provision confers on EPA. Michigan v. EPA, 213 F.3d 663, 680-81 
(D.C. Cir. 2000). As discussed in Unit II.A., as EPA interprets the 
requirements in section 313(f)(2), the standard operates as an 
effective constraint when the Agency increases the thresholds, but as a 
practical matter, cannot provide the same level of constraint when the 
Agency decreases the thresholds. However, as previously explained, EPA 
relied on this standard to elicit factors to guide its exercise of 
discretion. See, 64 FR 58687-692.
    But the mere fact that Congress provided neither explicit 
prerequisites in section 313(f)(2) to the Agency's determination that a 
lower threshold is warranted, nor a standard whose plain language 
effectively constrains EPA's discretion in selecting the appropriate 
lower threshold, does not necessarily render this provision 
unconstitutional. The issue is whether Congress granted the Agency too 
much discretion to modify the statutory thresholds--not merely whether 
Congress provided a standard to significantly constrain the Agency's 
discretion in lowering the thresholds. See Michigan v. EPA, 213 F.3d at 
680; International Union v. OSHA, 37 F.3d 665 (D.C. Cir. 1994). 
Examination of the former issue demonstrates that in section 313(f)(2), 
EPA's ``power to roam'' is relatively narrow.
    In section 313(f), Congress established thresholds as a baseline, 
and delegated authority to EPA to modify them provided that the 
``revised thresholds shall obtain reporting on a substantial majority 
of total releases of the chemical at all facilities subject to the 
requirements of this subsection.'' As previously explained, EPA 
interprets this to require that any revised threshold obtain reporting 
on a substantial majority of the total releases reported by facilities 
reporting under the existing, baseline thresholds. See, Unit II.A. 
supra, and 64 FR 58673-676. This standard effectively constrains EPA's 
ability to increase the thresholds, and thereby deprive government 
agencies, researchers, and local communities of information that would 
provide them with a comprehensive picture of toxic chemical releases 
and potential exposures to humans and ecosystems, contrary to EPCRA 
section 313's overriding purpose. The discretion exercised in this rule 
is EPA's discretion to establish thresholds between 0 and 10,000 pounds 
or 25,000 pounds; this can hardly be characterized as an ``immense 
power to roam.''
    Moreover, the impact of any revised threshold is distinctly 
limited, which courts have recognized as a relevant factor in 
evaluating the degree of authority that Congress delegates to an 
Agency. See, e.g., Michigan, 2000 WL 180,650 (``a mass of cases in 
courts had upheld delegations of effectively standardless discretion, 
and distinguished them precisely on the ground of the narrower scope 
within which the agencies could deploy that discretion''); American 
Trucking, 175

[[Page 4507]]

F.3d at 1037 (``The standards in question affect the whole economy, 
requiring a more precise delegation than would otherwise be the case'' 
(citations omitted)). Here, that means within the context of all of the 
other prerequisites Congress established for TRI reporting, and of the 
other relevant statutory provisions constraining the Agency's ability 
to modify those requirements. Irrespective of the modified threshold, a 
facility must still employ more than ten full-time employees; its 
primary SIC code must fall within one of the listed SIC codes; and it 
must be manufacturing, processing, or otherwise using one (or more) of 
the currently listed chemicals. 42 U.S.C. Sec. 11023 (b). And far from 
granting EPA unfettered discretion to expand these requirements, 
Congress selectively granted EPA carefully qualified authority to 
adjust individual parameters. For example, section 313(l) explicitly 
limits the Agency's authority to modify the reporting frequency, ``. . 
. but the Administrator may not modify the frequency to be any more 
often than annually.'' Similarly, Congress included no authority to 
amend the generally applicable employee threshold; thus facilities with 
fewer than ten employees are not subject to reporting under subsection 
313(b)(1). In section 313(g)(2), Congress also specifically restricted 
the Agency's ability to require industry to collect data to report 
under TRI: ``Nothing in [EPCRA section 313] requires the monitoring or 
measurement of the quantities, concentration, or frequency of any toxic 
chemical released into the environment . . .'' Accordingly, the scope 
within which EPA may deploy its discretion under EPCRA section 
313(f)(2) is fairly narrow, and its impact limited.
    In light of the above, EPA does not believe that the mere fact that 
the Agency is authorized to potentially select a threshold of ``0,'' 
necessarily renders section 313(f)(2) unconstitutional. The issue 
underlying the non-delegation doctrine, as the DC Circuit has explained 
is ``to make sure that the regulatory principles as applied have their 
origin in a judgement of the legislature,'' not whether Congress 
authorized the Agency to establish extremely low thresholds. 
International Union v. OSHA, 37 F.3d at 669 (citations omitted). Nor 
does the fact that Congress did not require the Agency to make specific 
findings to determine it was appropriate to increase or decrease 
section 313 reporting thresholds, necessarily demonstrate that Congress 
failed to provide the Agency with adequate guidance in delegating its 
authority under section 313(f)(2).
    One commenter further alleged that the Agency has failed to 
identify an intelligible principle ``to channel its application of 
these factors,'' quoting, American Trucking Association v. EPA. Another 
commenter asserts that EPA's reliance on the general purposes of EPCRA 
is insufficient, stating that ``general purposes or factors cannot 
substitute for the constitutionally required ``intelligible principle'' 
by which to identify a stopping point'' when setting levels or 
thresholds.
    As noted above, the Supreme Court has granted EPA's request to 
review American Trucking. Nonetheless, EPA disagrees that EPCRA section 
313(f)(2) falls afoul of the non-delegation doctrine, even as 
interpreted and applied in that case. As summarized above, in the 
preamble to the final PBT chemical rule, EPA identified and explained 
its application of the ``intelligible principle'' that Congress 
provided along with the delegation of authority in EPCRA section 
313(f)(2). See, 64 FR 58687-692.
    EPA also disagrees that its reliance on EPCRA section 313's general 
purposes to discern EPCRA section 313's overriding purpose, and thereby 
its intelligible principle, is insufficient. The DC Circuit upheld a 
broad delegation of legislative authority to OSHA based on the Agency's 
demonstration of legislative guidance found in the Act's ``overriding 
purposes.'' There, the Court noted

    Were the six itemized criteria the full statement of OSHA's 
interpretation of its statutory mandate, we might have to vacate the 
rule, because the agency might still have too much freedom to ``roam 
between the rigor of section 6(b)(5) standards and the laxity of 
unidentified alternatives. International Union I, 938 F.2d at 1317. 
But OSHA has gone on to infer from various sections--that the Act's 
``overriding purpose'' is ``to provide a high degree of employee 
protection.'' 58 FR 16, 614/3-15/1. Thus the Agency reads the Act to 
require it, once it has identified a ``significant'' safety risk to 
enact a safety standard that provides ``a high degree of worker 
protection.''Id. at 16, 615/1. It is not permitted to ``do nothing 
at all'', as we had earlier suggested. Id. (quoting International 
Union I, 938 F.2d at 1317). Rather, OSHA reads the Act to permit it 
to deviate only modestly from the stringency required by section 
6(b)(5) for health standards. Accordingly, as construed by OSHA, the 
Act guides its choice of safety standards enough to satisfy the 
demands of the nondelegation doctrine. (citations omitted). 
International Union v. OSHA, 37 F.3d at 669 (emphasis added).
    The Court also explained that the underlying purpose of non-
delegation doctrine is ``to make sure that the regulatory principles as 
applied have their origin in a judgement of the legislature.'' Id. 
(citations omitted). EPA believes that its application of EPCRA section 
313(f)(2) in this rule, as well as in the PBT rule, similarly satisfy 
the demands of the nondelegation doctrine.

C. What Science Issues Were Raised by Commenters on the Persistence and 
Bioaccumulation Criteria?

    Several commenters contend that the criteria articulated in the PBT 
chemical rule to characterize the persistence and bioaccumulation of 
toxic chemicals should not be applied to metals because the development 
of the persistence and bioaccumulation criteria (as discussed in the 
PBT chemical rulemaking, see 64 FR 688-729) was based largely on data 
pertaining to organic substances. Thus they contend it is inappropriate 
to use these criteria to determine whether inorganic substances, 
including inorganic metal compounds, should be classified as PBT 
chemicals.
    The Agency disagrees with the commenters' statement that the PBT 
rule framework developed by EPA to assess the persistence and 
bioaccumulation of EPCRA section 313 listed toxic chemicals was 
designed only for organic substances and is being incorrectly applied 
to metals. The development of EPA's framework to assess persistence and 
bioaccumulation is described in detail in the PBT chemical rulemaking 
(see 64 FR 688-729) and in the proposed lead rule. This framework was 
not developed to assess only whether organic chemicals are persistent 
and/or bioaccumulative, but to assess whether any chemical substance is 
persistent and/or bioaccumulative, including metals and metal 
compounds. EPA notes that the public had the opportunity to comment on 
the applicability of the PBT rule criteria to metals in the PBT 
chemical rulemaking. Furthermore, in the PBT chemical rulemaking, the 
Agency applied these criteria to mercury and mercury compounds--a metal 
and metal compounds category. EPA also provided notice in the proposed 
PBT chemical rulemaking that it was continuing to evaluate the 
bioaccumulation data for lead and lead compounds, and for cobalt and 
cobalt compounds--also metals (64 FR 717). EPA made clear the PBT rule 
criteria were developed to apply to metals and metal compounds, as well 
as organic compounds and, in fact, has applied the criteria to metals 
and metal compounds in a previous notice and comment rulemaking. With 
respect to the half-life and BCF/BAF criteria, scientifically these 
criteria are quite applicable to metals. Finally in the

[[Page 4508]]

lead proposed rule, EPA identified an additional factor for use in 
determining whether a chemical is, at the least, bioaccumlative. EPA 
explained that there is clear and convincing evidence that lead is 
bioaccumulative in humans. However, EPA requested comment on how such 
human data should be considered in determining whether a chemical 
should be classified in that subset of PBT chemicals that are highly 
bioaccumulative. Commenters argue that the human data should not be 
used to classify lead as bioaccumulative because the quantities of lead 
that might be reported, they believe, would not reduce human exposures 
to lead that are of concern. As explained elsewhere, EPA does not 
believe that human data showing the bioaccumulation nature of lead in 
humans should be ignored in any assessment of lead's bioaccumulation 
potential simply on the theory that the level of lead to which humans 
are exposed and the levels observed in humans may not correlate to the 
additional information on land release collected under this rule.
    Persistence, bioaccumulation, and toxicity are three distinct, 
independent characteristics. Although in the PBT chemical rulemaking 
the experimental evidence used to derive the environmental half-life, 
BAF and BCF criteria were obtained largely from studies that involved 
organic substances, this does not preclude the application of these 
criteria to inorganic substances such as metals and metal compounds 
(including lead and lead compounds). The basis for the concern and 
reason for lowering thresholds is based on the ability of the chemical, 
whether it is an organic chemical or a metal compound, to persist and 
bioaccumulate. The Agency believes that these criteria should and must 
be applicable to all chemical substances, including metals and metal 
compounds. EPA provided a detailed response to the issue of metals as 
PBT chemicals in the PBT chemical rulemaking. Persistence and 
bioaccumulation are not dependent upon whether a substance contains 
carbon (i.e., is organic). Substances that are inorganic can persist 
and bioaccumulate. The underlying molecular properties that determine 
whether a substance can persist and bioaccumulate are fundamentally the 
same for organic chemicals as they are for inorganic chemicals, 
including metals and metal compounds. These properties, as with most 
chemical and biological properties of a substance, are more dependent 
on the electronic and steric characteristics of the atoms comprising a 
substance, the specific arrangement of the atoms within the substance's 
molecular structure and, with regard to bioaccumulation, the 
pharmacokinetics of the substance within the exposed organism and the 
sensitivity of the organism to the substance.
    In addition, it is scientifically valid to establish generic 
criteria that are applicable to all substances provided that the 
endpoint or purpose for which the criteria are being established 
provides a common thread that is not dependent upon the unique elements 
comprising any given substance. For example, it would be legitimate to 
establish a category based on a type of arsenic toxicity and include 
within that category any substance that contains arsenic and exhibits 
that toxicity regardless of whether individual substances are organic 
or inorganic. In fact, it is common practice for scientific 
organizations and regulatory agencies to use generic criteria of this 
type. One example is the criteria established by the National 
Toxicology Program (NTP) for characterizing chemical carcinogens. The 
NTP is required by law to establish a list of all substances which 
either are known to cause cancer in humans, or may reasonably be 
anticipated to cause cancer in humans. A criterion used by the NTP to 
characterize chemicals as known or possible human carcinogens include, 
among others, tumor incidences in humans or experimental animals. While 
the vast majority of substances reviewed and tested by the NTP for 
carcinogenicity are organic substances, and the criterion established 
by NTP was based largely from toxicological observations pertaining to 
organic substances, the criterion used by the NTP is the same for 
inorganic substances as it is for organic substances. The NTP does not 
use different criteria when evaluating inorganic substances. This is 
because the ability of a substance to cause cancer is not dependent 
upon whether the substance is organic. In fact, NTP's current list of 
substances that are known to be human carcinogens contains both 
inorganic (including metallic) and organic substances. The 
carcinogenicity of all of these substances were characterized by the 
same generic criterion. A detailed discussion of the criteria used by 
the NTP is available (Ref. 17).
    1.What comments did EPA receive on the persistence of metals and 
metal compounds? EPA defines a chemical's persistence as the length of 
time the chemical can exist in the environment before being destroyed 
by natural processes. Numerous commenters suggested that EPA adopt a 
different definition of persistence for metals and metal compounds. 
They assert that the definition of persistence as applied to metals and 
metal compounds should include the transformation of individual metal 
compounds in the environment. As discussed in detail in the following 
response to comments on this issue, EPA believes that these factors are 
irrelevant to the persistence of metals and metal compounds in the 
environment. The factors that the commenters contend should be 
considered are those which address the conversion of one metal compound 
to another, which is irrelevant in determining whether metal compounds 
are persistent. While these are factors which control the 
transformation of one metal compound to another compound of the same 
metal, they are not factors which result in the destruction of the 
metal. There are no environmental factors which can or will result in 
the destruction of the metal.
    Some commenters disagree with EPA's definition of persistence. They 
contend that the definition of persistence should be based on the 
availability of the metal in various environments and the length of 
time the metal is retained in an organism. One of these commenters 
stated that ``persistence is the length of time an element or compound 
is available to and/or is retained in an organism or an ecological 
community, and that the mobility of metals [such as lead] deposited in 
soils or aquatic sediments becomes an important question when 
discussing persistence, since they are not persistent in biota unless 
they reach those environmental compartments and are cleared more slowly 
than they accumulate.''
    EPA disagrees with the commenter's definition of persistence. In 
the PBT chemical rulemaking (64 FR 58666), EPA adopted a policy for use 
in classifying a toxic chemical as persistent under EPCRA section 313. 
In the proposed rule to lower the reporting thresholds of lead and lead 
compounds (64 FR 42222), EPA used this same policy to determine whether 
lead and lead compounds are persistent. Most of these comments address 
the issue of persistence generically rather than specifically to lead 
and lead compounds. EPA responded to these generic issues in the PBT 
chemical rulemaking (64 FR 58676) and in sections 2a-f of the 
associated Response to Comments document (Ref. 15). EPA is discussing 
these issues here as background for the individual issues specific to 
lead and lead compounds in order to assist in understanding EPA's 
responses. Persistence is the length of

[[Page 4509]]

time a chemical can exist in the environment before being destroyed by 
natural processes (64 FR 698 and 64 FR 42227). The environmental media 
for which persistence is measured or estimated include air, water, 
soil, and sediment. It is important to distinguish between persistence 
in a single medium (air, water, soil or sediment) and overall 
environmental persistence. Persistence in an individual medium is 
controlled by transport of the chemical to other media. Persistence in 
the environment as a whole, however, is a distinct concept. It is based 
on observations that the environment behaves as a set of interconnected 
media, and that a chemical substance released to the environment will 
become distributed in these media in accordance with the chemical's 
intrinsic properties and reactivity. For overall persistence, only 
irreversible transformation contributes to net loss of a chemical 
substance. With regard to metals, although metals and metal compounds, 
such as lead and lead compounds, may be converted from the metal to a 
metal compound or from one metal compound to another in the 
environment, the metal itself cannot be destroyed. A metal by its very 
nature cannot be destroyed and, therefore, is persistent in the 
environment as the metal or a metal compound.
    The primary purpose of the persistence criterion is to establish 
how long a chemical substance will remain in the environment. The 
greater the length of time a substance persists in the environment, the 
greater is the potential for all forms of life to be exposed to the 
substance. Persistence is not limited to the duration of time a 
chemical is present in an organism and EPA does not believe it would be 
appropriate to incorporate this concept into its definition of 
persistence. It should be noted that, unlike the commenter's definition 
of persistence, EPA's definition of persistence does not specifically 
address the longevity of a substance in an organism. Persistence of a 
substance in the environment as a whole, or even in a particular 
environmental medium, is fundamentally unrelated to the substance's 
biological persistence (i.e., length of time a chemical exists in an 
organism before being destroyed or excreted). Although there are a few 
factors (physicochemical factors; e.g., water solubility, reactivity) 
that have a similar influence on environmental persistence as they do 
on the biological persistence of a substance, there are a number of 
other factors that influence biological persistence but not 
environmental persistence. These other factors are organism specific, 
and are related to the anatomical and physiological characteristics of 
the organism. The Agency believes its environmental persistence 
criterion should not be extended to include biological persistence 
because the factors that influence the two persistence types are 
largely unrelated. Biological persistence in a given organism does not 
provide any information as to how long a substance will remain in the 
environment, and therefore is not relevant to the definition of 
persistence for EPCRA section 313.
    One commenter claims that there is a serious flaw in the Agency's 
reasoning in characterizing all elements, including metals, as being 
persistent. Specifically, this commenter claims that this reasoning 
implies that because elements are non-destructible, then any compounds 
that contain a particular element is also non-destructible. The 
commenter acknowledges that EPA makes the statement in the proposed 
lead rule that ``specific metal compounds may or may not be persistent, 
depending on the form of the metal and environmental conditions, but 
the elemental metal itself obviously meets the definition of 
persistence.'' The commenter claims that this statement begs the 
questions as to why EPA is not evaluating specific metal compounds when 
the Agency acknowledges that metal compounds differ in their 
``persistence'' and also differ substantially with respect to toxicity 
and bioaccumulative potential. The commenter states that the above 
quoted statement could just as easily read ``. . . specific carbon 
compounds may or may not be persistent, depending on the form of carbon 
and environmental conditions, but the elemental carbon itself obviously 
meets the definition of persistence.'' The commenter asserts that, 
according to EPA, this would mean that all organic compounds are 
persistent because they contain carbon and carbon is persistent. The 
commenter states that the Agency does not adopt such reasoning 
regarding elemental carbon because it would render the PBT chemical 
assessment methodology useless as an assessment tool. The commenter 
recommends that the Agency not apply the persistence assessment 
methodology to metals for the same reasons.
    Another commenter believes that EPA's criteria for persistence as 
it applies to characterizing the persistence of metals is unfair. 
Specifically, this commenter interprets EPA's persistence assessment 
methodology as saying ``. . . since any metal is persistent in the 
environment by definition, every compound of that metal is evaluated 
and regulated by EPA like the parent metal, even if there are no data 
on that compound's persistence, even if the persistence in the 
environmental medium of its concern is very short, and even if that 
compound's bioavailability is insignificant.''
    The Agency believes that both of these commenters have 
misinterpreted the PBT assessment methodology EPA applied to lead and 
lead compounds.
    With respect to the commenter who questioned why EPA is not 
evaluating the persistence of compounds individually, EPA disagrees 
that it is either scientifically required, or necessary for purposes of 
EPCRA section 313, to evaluate the persistence of each lead compound 
individually. lead compounds are listed under EPCRA section 313 as a 
category; this means that all of the individual chemical compounds 
share common chemical characteristics, such that it is scientifically 
reasonable to conclude that lead compounds exhibit common toxicological 
properties/exhibit similar toxicity. For lead compounds, as for all 
metal compounds listed in an EPCRA section 313 metals category, the 
relevant common chemical property is the metal, because the toxic 
constituent is the metal itself, and this is what defines the category. 
Thus, in evaluating the persistence of lead compounds as an EPCRA 
section 313 chemical category, the relevant issue for purposes of EPCRA 
section 313 is the persistence of lead rather than the persistence of 
the other chemical constituents of the compounds in the category.
    Similarly, EPA believes that this commenter's analogy to carbon and 
organic compounds is misguided. Organic compounds differ significantly 
from metal compounds in that the presence of carbon in a compound is 
not a controlling feature in the way that a metal contained in a metal 
compound is controlling. For example inorganic arsenic compounds are 
classified as known human carcinogens (Ref. 18). The toxicity is 
specific to the fact that the compounds contain arsenic and not to the 
other parts of the arsenic compounds. This is not the case with all 
groups of carbon compounds. For example, classes of organic chemicals 
that contain oxygen such as ketones, alcohols, ethers, and carboxylic 
acids exhibit significantly different physical and chemical properties 
and toxic effects. This is due to the differing arrangement of the 
carbon and oxygen within the compound. Even chemicals within the same 
class of organic chemicals, e.g., ketones, may not exhibit the same 
toxicity or similar physical

[[Page 4510]]

chemical properties. Further, while one arsenic compound will be 
converted in the environment or in vivo, it will not be converted into 
a substance that does not contain arsenic. In the environment or in 
vivo degradation of one member of a group of organic chemicals, e.g., 
ketones, carboxylic acids, will not consistently be converted into 
another chemical of the same class. They will often be converted into a 
different class of organic chemical.
    Thus, while the Agency agrees that elemental carbon is persistent, 
the Agency would not conclude that all organic substances are 
persistent simply because they contain carbon. This is because the 
toxic effects of organic compounds are attributable to the structure of 
the compounds and not the carbon contained in the compounds. Thus EPA 
would not list a chemical category consisting of carbon and all carbon 
containing compounds, nor would it make a determination using the PBT 
assessment methodology that such compounds are PBT chemicals because 
they contain carbon. The same is true for any other element that is not 
toxic.
    This approach is consistent with the Agency's approach to listing 
chemical categories, where, in the absence of data on a particular 
member of the category, EPA adds a chemical category, such as a metal 
compound category, based on their common chemical characteristics, and 
without demonstrating separately that each individual member of the 
category meets the section 313(d)(2) criteria. The D.C. Circuit 
specifically upheld this approach with respect to listing categories, 
finding that EPA's action was reasonable (Troy v. Browner, 120 F.3d 
277, 288-89 (D.C. Cir. 1997).
    In addition, the commenters imply that in using the PBT rule 
assessment methodology EPA would conclude that all metals and their 
compounds are persistent and bioaccumulative, and therefore the Agency 
would require that all metals and their compounds that are listed on 
the EPCRA section 313 list of toxic chemicals have reduced reporting 
thresholds. The Agency would like to emphasize that while all metals 
persist, many metals and their compounds would not be characterized by 
EPA as bioaccumulative and toxic. For a listed toxic chemical to be 
considered a PBT chemical, the toxic chemical must be sufficiently 
persistent and sufficiently bioaccumulative.
    Several commenters disagree with the Agency's rationale for 
characterizing all metals as being persistent, and believe that the 
issue of persistence has little or no relevance to metals.
    The Agency disagrees with the commenters' statement that the issue 
of persistence has little or no relevance to metals. EPA believes that 
persistence is relevant to the hazard potential of metals such as lead 
for the same reason persistence is relevant to the hazard potential of 
organic chemicals: for a chemical that persists in the environment, 
there is a greater potential for exposure and, therefore, a greater 
potential for the chemical to cause toxicity in an exposed organism or 
individual. However, in this rulemaking the Agency did not rely on the 
property of persistence by itself in lowering reporting thresholds for 
lead and lead compounds, nor does persistence alone necessarily mean 
that a substance is or can be a hazard to human health and the 
environment. As stated above, to be classified as a PBT chemical, a 
chemical must: (1) Be an EPCRA section 313 listed toxic chemical; (2) 
be sufficiently persistent; and (3) be sufficiently bioaccumulative. In 
this rulemaking EPA is addressing lead and lead compounds which are 
EPCRA section 313 listed toxic chemicals and is also considering the 
bioaccumulation potential of these chemicals.
    One of the commenters believes that metals do not necessarily 
persist, and that the definition of persistence in relation to metals 
should be qualified to mean how long a metal can remain in a particular 
form or species (e.g., oxidation state). This commenter also recommends 
that the Agency should examine data pertaining to certain properties of 
metals to assess persistence in accordance with this definition, and to 
allow for the identification of those metals and metal species which 
are the most/least resistant to change and which are the most or least 
bioavailable. The properties raised by the commenters include: 
transformation/dissolution, oxidation, corrosion, sulfide binding, and 
first hydrolysis constant.
    EPA agrees with the commenter's statement that metals, including 
lead, can exist as different species and compounds. These different 
species pertain to the oxidation states or, more specifically, the 
number of electrons missing from the outer orbital of the metal atom. 
Lead, for example, can exist in a neutral species, Pb<SUP>0</SUP> (no 
electrons are missing from the outer electron orbital of the lead 
nucleus), or as lead compounds in one of two oxidation states: 
Pb<SUP>+2</SUP> or Pb<SUP>+4</SUP> (2 and 4 electrons are missing from 
the outer electron orbital, respectively). As stated in the proposed 
rule, these species can convert from one to another under certain, 
commonly encountered environmental conditions. See also Unit VI.C.5. of 
this preamble. While there may be a conversion from one lead compound 
to another lead compound or to metallic lead, or from metallic lead to 
a lead compound (either in the Pb<SUP>+2</SUP> or Pb<SUP>+4</SUP> 
oxidation states), there is no possible conversion either in the 
environment or in vivo that will convert (or degrade) metallic lead or 
any lead compound into a substance that does not contain lead. Any 
conversion will always result in the presence of lead or a compound 
that contains lead. Conversion of a metal atom from one oxidation state 
to another does not change the number of protons in the nucleus of the 
atom and, therefore, does not change the metal into another metal or 
element. In the case of lead, each species of lead (Pb<SUP>0</SUP>, 
Pb<SUP>+2</SUP>, and Pb<SUP>+4</SUP>) is still lead because each 
contain the same number of protons (82) within their nuclei (See Refs. 
19 and 20).
    EPA disagrees with the commenter's assertion that the Agency 
consider transformation/dissolution, oxidation, corrosion, sulfide 
binding, and first hydrolysis constant in determining whether metal 
compounds are persistent. These are factors which address the 
conversion of one metal compound to another, which is irrelevant in 
determining whether metal compounds are persistent. While these are 
factors which control the transformation of one metal compound to 
another compound of the same metal, they are not factors which result 
in the destruction of the metal. There are no environmental factors 
which can or will result in the destruction of the metal. Therefore, 
EPA believes that the commenter's definition of persistence is not an 
appropriate alternative to EPA's definition.
    One commenter who agrees with EPA's definition of persistence and, 
in particular the Agency's characterization of lead as being persistent 
states that the persistency of lead poses a significant threat to human 
health and the environment because this property allows lead to remain 
in the environment without being broken down by natural processes. This 
commenter disagrees with other commenters who claim that metals are not 
persistent or that persistence of toxic metals should not be of 
concern. This commenter believes that persistence enables a substance 
like lead to travel through ecosystems and through different media and, 
as such, threatens human health and the environment far beyond the 
geographic vicinity of the source from which it has been released.
    The Agency agrees with the commenter's statement that lead is 
persistent. The Agency also agrees that

[[Page 4511]]

the persistence property of a substance contributes to the ability of 
the substance to be distributed through ecosystems and through 
different media to areas beyond the geographic vicinity from where the 
substance entered the environment. The property of persistence, 
however, pertains to longevity of a substance, and does not bestow an 
ability for the substance to partition throughout environmental media. 
However, the opportunity for exposure to a substance that is capable of 
partitioning throughout environmental media may be greater if the 
substance is also persistent, since the substance will remain in the 
environment for a longer period than a substance that is not persistent
    2. What comments did EPA receive on the availability and 
bioavailability of metal compounds? Commenters suggest that EPA 
consider environmental availability (which they term 
``bioavailability'') in lieu of bioaccumulation. Many of these 
commenters assert that unless a metal compound is readily available in 
the environment, it will not be bioavailable or bioaccumulate. Some 
attempt to take a risk-based approach to metals and metal compounds in 
the environment by arguing that when environmental availability is 
considered, metals and metal compounds will not be present at levels 
high enough to cause adverse effects.
    As discussed in detail below, the level of environmental 
availability or bioavailability is not a surrogate for bioaccumulation. 
Even metal compounds that have limited availability or bioavailability 
can bioaccumulate. The extent of environmental availability or 
bioavailability will not affect whether bioaccumulation will occur. For 
example, lead from a sparing soluble compound and lead from a readily 
soluble compound will both bioaccumulate. This is in contrast to the 
commenters' implication that only the lead from the readily soluble 
lead compound will bioaccumulate. Further as discussed below, the 
presence of a soluble metal compound is not the only factor, or in many 
cases the determining factor, that controls the potential for the metal 
compound to bioaccumulate. A metal compound may undergo various 
transformations in the environment resulting in a different metal 
compound which has a much higher availability and/or bioavailability. 
While metals and metal compounds need to be environmentally available 
and/or bioavailable as a prerequisite to bioaccumulation, there is not 
a quantitative relationship between environmental availability and/or 
bioavailability and the degree of bioaccumulation. Therefore, EPA 
believes that availability and bioavailability are not appropriate 
substitutes for bioaccumulation.
    Further, requiring a particular level environmental availability 
would effectively be establishing a risk-based approach to lowering 
thresholds which EPA believes is inappropriate for the following 
reasons. The availability of lead in the environment will vary 
depending upon environmental conditions. Choosing one level of 
environmental availability and applying that individually to each metal 
compound is neither practical nor scientifically supportable because: 
(1) As discussed above environmental availability is not necessarily 
reflective of bioavailability; and (2) the environmental availability 
of a metal compound depends upon local environmental conditions. There 
is no ``best'' or adequately representative set of national 
environmental conditions. Further, the TRI program is primarily a 
hazard based program. Risks that may be acceptable at the national 
level may not be acceptable at a regional or local level.
    EPA considers availability in the environment and bioavailability 
for metal and metal compounds for purposes of bioaccumulation only to 
determine whether it is impossible for the metal and metal compounds to 
bioaccumulate, i.e., a compound that is both environmentally and 
biologically inert cannot bioaccumulate. EPA believes that there are 
data that indicate that lead and lead compounds are available in the 
environment, are bioavailable, and bioaccumulate, e.g., data in humans 
and fish advisories. However, several commenters contended at public 
meetings on EPA's PBT chemical rulemaking that metals and metal 
compounds, such as lead and lead compounds, are not available in the 
environment and thus, cannot bioaccumulate. To address these comments, 
EPA chose to conduct an environmental fate assessment to describe the 
environmental availability of lead and lead compounds. Qualitative 
environmental fate assessments are generally part of a hazard 
assessment for a chemical. The qualitative environmental fate 
assessment for lead and lead compounds, however, was not developed, nor 
was it intended, to be part of an exposure assessment or risk 
assessment.
    Several commenters claim that EPA should consider bioavailability 
in its assessment of metals and metal compounds, such as lead and lead 
compounds. These commenters contend that not all metal compounds and 
lead compounds in particular are bioavailable. According to the 
commenters, unless a compound is in a form that is bioavailable, it 
will present little risk to human health and the environment. One 
commenter made the following statement:

    Because of metals' natural persistence, the weight of scientific 
opinion holds that bioavailability is a more appropriate criterion 
for assessing the environmental and health hazards associated with 
metals. While toxicity is obviously a relevant measure for assessing 
the hazard posed by a substance, the substance must be available for 
uptake [bioavailable] before it can exhibit an adverse effect. 
Bioavailability varies significantly among different species of 
metals, including lead compounds, and also is influenced by 
environmental media. Bioavailability can only occur if soluble metal 
compounds are released. Thus, the rate at which metals transform to 
soluble/bioavailable species is critical for hazard identification. 
Simply stated, the natural persistence of metals with toxic 
properties poses no special hazard if those metals generally are 
present in environmental media in forms that cannot be taken up by 
plants and animals.

    Other commenters expressed similar views. These commenters believe 
that the availability of lead from lead compounds differs among lead 
compounds, and that lead is unavailable from certain lead compounds. 
Therefore, in the opinion of the commenters, lead compounds from which 
lead is not available and/or bioavailable cannot be PBT chemicals, and 
should not be included in this rulemaking.
    The Agency disagrees with the commenters assertions that: (1) EPA 
did not consider bioavailability of lead in its assessment of lead and 
lead compounds as bioaccumulative substances; and (2) that 
bioavailability is only possible for released soluble metal compounds.
    The basis for the Agency's disagreement with these comments 
concerns the commenters use of the terms ``availability'' and 
``bioavailability'', which differs significantly from EPA's definition 
of these terms. The commenters are using the term bioavailability 
interchangeably with availability, when in fact these two terms have 
totally different meanings and cannot be used interchangeably. In 
addition, the commenters have incorrectly concluded that: (1) If lead 
is not available in the environment, it is not bioavailable and will 
not bioaccumulate or cause toxicity; (2) lead is only bioavailable when 
in its ionic oxidation state; and (3) only those lead compounds that 
are water soluble as released are bioavailable. To respond to

[[Page 4512]]

these comments, the Agency needs to first clarify the distinction 
between ``availability'' of a metal, and ``bioavailability'' of a metal 
or metal compound, and the factors that influence availability and 
bioavailability of a metal or metal compound.
    Availability of a metal is the extent to which a metal, in either 
its neutral (MG<SUP>0</SUP>) or ionic (MG<SUP>+x</SUP>) oxidation 
state, can reach a state of atomic disaggregation. Inorganic metal 
compounds that are water soluble will completely dissociate in aqueous 
media, liberating the metal in its ionic oxidation state. In aqueous 
solution the metal atoms of the molecules of these substances are 
completely disaggregated from the rest of their molecular constituents. 
In this disaggregated state the metal is completely available. Water 
solubility is not a prerequisite, however, for a metal to become 
available from a metal compound. In the environment a metal can become 
available from organometallic substances or inorganic metal compounds 
that are poorly soluble in water, by undergoing environmental 
transformations that cause the metal atoms to dissagregate and become 
available. Environmental transformations that cause metals to become 
available are summarized below, and discussed in greater detail in Unit 
V.A. of the proposed lead rule (64 FR 42227-42228), and in The 
Environmental Fate of Lead and Lead Compounds (Ref. 2).
    The extent to which a metal can become available from a metal 
compound in environmental media is dependent upon: (1) The 
physicochemical properties of the metal and the metal compound; (2) the 
structural characteristics of the metal compound; and (3) environmental 
factors, including, but not limited to: presence of aerobic or 
anaerobic bacteria, pH, moisture content, and organic matter content of 
soil or sediments. Some or all of these environmental factors can vary 
between specific terrestrial or aquatic environments. For different 
compounds that contain the same metal, the relative availability of the 
metal from each compound can vary within the same terrestrial or 
aquatic environment. It is also true that the availability of a metal 
from the same metal compound can vary between specific terrestrial or 
aquatic environments. Some metal compounds are more susceptible to 
environmental transformations and subsequent release of the metal than 
are other metal compounds.
    Bioavailability is the extent to which a substance is absorbed by 
an organism, and distributed to an area(s) within the organism. This is 
important because the substance can then exert a toxic effect or 
accumulate. As with availability, the physicochemical and structural 
characteristics of a substance play an important role in determining 
whether the substance is bioavailable and the extent to which it is 
bioavailable. Unlike availability, however, whether a substance is 
bioavailable and the extent to which it is bioavailable in a given 
organism also depends upon the anatomy and physiology of the organism, 
the route of exposure, and the pharmacokinetics of the substance in the 
organism (i.e., the extent to which the substance is or can be absorbed 
by the organism from the exposure site, its distribution and metabolism 
within the organism, and its excretion from the organism). It is 
important to stress that bioavailability does not by itself mean that a 
substance is a hazard to human health or the environment. A substance 
that has 100% bioavailability does not pose a hazard to human health or 
the environment if it is not intrinsically toxic. Conversely, for 
substances that are intrinsically toxic it is not necessary for the 
substance to be 100% bioavailable to cause toxicity. Depending upon the 
extent of exposure, toxic potency, and the nature of the toxic effect, 
even substances that have low bioavailability can still pose a hazard 
to human health or the environment. Similarly, a substance does not 
have to have 100% bioavailability in order for it to bioaccumulate. For 
some compounds, even very limited bioavailability (that is a very small 
percentage is bioavailable) can result in concern if it is 
bioaccumulated. Lead and lead compounds are one example. 
Polychlorinated biphenyls (PCBs) are another (64 FR 706).
    Absorption of a substance is a critical component of its 
bioavailability. Absorption is the movement of a chemical substance 
from its site of exposure on a terrestrial or aquatic life form into 
its systemic circulation (bloodstream) or, in the case of unicellular 
organisms such as algae, inside the cell comprising the organism. In 
any case, absorption of a substance from any exposure site involves its 
passage across the biological membranes that compose the exposure site. 
Chemicals can cross a cell membrane by several mechanisms. These are: 
(1) Passive permeation (diffusion) through the membrane; (2) passive 
transport through membrane channels or pores; (3) active transport; 
facilitated transport; or (4) phagocytosis (also pinocytosis and 
endocytosis) (Ref. 21). Whether a substance can or will be absorbed, 
and the degree to which it can be absorbed depends largely upon the 
physicochemical properties of the substance, the anatomical makeup of 
the exposed organism and the site of exposure (Ref. 21). Substances 
released to the environment that are not absorbable by terrestrial or 
aquatic species may be transformed in the environment to metabolites 
that are absorbable and, hence, bioavailable.
    An important point to stress regarding the bioavailability of 
metals is that availability of a metal is not a prerequisite for its 
bioavailability. Metals can be bioavailable in either their neutral 
(MG<SUP>0</SUP>) or ionic (MG<SUP>+x</SUP>) oxidation states; or as 
part of an intact inorganic or organic compound. When in ionic 
oxidation states many metals are generally absorbed by active transport 
processes. Here, cellular membrane-bound proteins carry the metal 
across the cell membrane and into the cell. While it would seem that 
most metal ions are sufficiently small and water soluble to simply pass 
through membrane channels, their hydrated ionic radii are usually too 
large to permit their passage by this mechanism. Metals in their 
neutral or ionic oxidation states may be taken up by organisms by 
phagocytic processes as well. Organometallic substances are substances 
in which the metal is bonded to carbon-containing substituents. These 
substances can be absorbed intact by passive diffusion. The absorption 
of poorly water soluble inorganic metallic substances can occur via 
phagocytosis, or by other mechanisms. In terrestrial or aquatic life 
forms that have digestive systems that secrete strong acids, a poorly 
water soluble inorganic metallic substance or a metal in its neutral 
oxidation state can react (following oral exposure to the substance) 
with the acid to form a water soluble salt of the metal. Under these 
circumstances the metal is made available within the digestive system, 
and is absorbed in its ionic oxidation state. See Refs. 21, 22, 23, and 
24.
    The distribution, metabolism, and rate of excretion of a metal or 
metal compound depends upon the nature of the metal or metal compound, 
and the anatomy, physiology and genetic makeup of the organism. Metals 
absorbed in their neutral or ionic oxidation state be excreted 
unchanged or react with endogenous substances to form a metal compound 
in vivo. Organometallic substances are typically more lipid soluble 
than is the metal in its neutral or ionic oxidation state, and can be 
distributed more readily to areas of the organism that otherwise may be

[[Page 4513]]

poorly accessible by the metal in its neutral or ionic oxidation state. 
Organometallic substances may also undergo metabolic transformations in 
vivo in which the metal is liberated from its organic constituents. The 
same is true for inorganic metallic substances absorbed intact. See 
Refs. 24, 25, and 26.
    Generally the ionic oxidation states of metals are the most 
available and, for many life forms, the most bioavailable. For aquatic 
species the bioavailability of a metal is expected to be greater from 
those metal compounds in which the metal is readily available in 
aquatic environments than from metal compounds or complexes in which 
the metal is not readily available in aquatic environments. This is 
because the metal is in a completely disaggregated state and dissolved 
in the aqueous media of the aquatic environment, which favors uptake of 
the metal by aquatic organisms since they are typically immersed in the 
aqueous media. However, aquatic species can also absorb intact metal 
compounds (e.g., organometallic substances). Thus, metals may be 
bioavailable from metal compounds or metal complexes even where the 
metal is not available in aquatic environments. Many aquatic organisms 
such as mussels, clams, and oysters, for example, consume as food 
organic materials suspended in aqueous media. These molluscs use short, 
hairlike locomotory organelles (cilia) to take in suspended organic 
materials from the water. Water currents sweep the suspended organic 
materials into the open shells, where they become fastened to a film of 
mucus. The cilia sweep the mucus to the mouth of the mussel. Soft, 
fingerlike organs push the mucus and organic materials into the mouth 
of the mussel, where it is taken in and digested. As stated by EPA in 
the proposed rule regarding lead and lead compounds, and by many 
commenters, lead dissolved in aqueous media may be removed from 
solution through sorption to suspended organic matter. Although no 
longer available, the lead in these suspended complexes may still be 
bioavailable in aquatic life forms that consume solid organic materials 
as food. Another example is that fish can absorb organometallic 
substances (intact) via passive diffusion through their gill membranes. 
See Refs. 24, 27, and 28.
    The availability of a metal from the same metal compound may vary 
in different terrestrial or aquatic locations. Differences in 
environmental conditions lead to differences in the environmental fate 
of the compound in different environments. In an aquatic environment 
that contains metal ions of the same metal, the bioavailability of the 
metal in different aquatic species may vary even though the 
availability of the metal to each species is the same (i.e., the 
concentration of the metal in its ionic oxidation state is the same 
throughout the aquatic environment). These differences in 
bioavailability in different aquatic species are due to the differences 
in anatomy, physiology, and pharmacokinetic differences among the 
species. For different compounds that contain the same metal, the 
bioavailability of the metal ion in a given organism within a 
particular terrestrial or aquatic location may vary among different 
compounds. For a given organism, differences in bioavailability of a 
metal among compounds that contain the metal may be ascribed to 
differences in the physicochemical properties of the metal compounds 
and pharmacokinetic differences.
    As mentioned above, metals or metal compounds released to the 
environment from anthropogenic sources are affected by prevailing 
environmental conditions, meaning broadly the wide variety of physical, 
chemical and biological processes that act upon them. These processes 
collectively determine the metal compounds in which the metal can exist 
in the environment. Lead can enter the environment as available or 
bioavailable compounds, or as compounds that are not available or 
bioavailable. However, lead that enters the environment as compounds 
that are not available or bioavailable can be converted in the 
environment to compounds that are available or bioavailable. As 
mentioned above, the ionic oxidation states of metals are generally the 
most available and, for many organisms, the most bioavailable. Hence, 
environmental factors that affect the availability of a metal may 
indirectly affect the bioavailability of metal. It is therefore 
important to consider those factors that influence the availability of 
a metal in the environment, when assessing physical or biological 
properties of the metal. However, as also discussed above, availability 
of a metal is not a prerequisite for its bioavailability. 
Interconversion of inorganic metal compounds can be quite rapid and as 
a result the metal compound in which the metal is released may not be 
the predominant metal compound post-release. Availability of a metal 
from an organometallic compound or insoluble inorganic compound is 
affected by many factors and its determination is complex, but many of 
the more important variables are discussed below for lead. A detailed 
discussion of the environmental fate of lead, that is illustrative of 
many of the more important environmental variables that affect 
availability and bioavailability of metals in general is provided in 
Unit V.A. of the proposed rule (64 FR 42227-42228), in The 
Environmental Fate of Lead and Lead Compounds (Ref. 2), and below.
    In some instances, after deposition in the soil environment, lead 
may bind strongly by mechanisms such as the formation of insoluble 
complexes with organic material, clay minerals, phosphate, and iron-
manganese oxides common in many soils. However, some of the lead in the 
soil environment (0.2 to 1%) may be water soluble. The extent of 
sorption appears to increase with increasing pH. Under acidic 
conditions, levels of lead in soil water can increase significantly. 
(The solubility of lead increases linearly in the pH range of 6 to 3.) 
Cation exchange capacity (CEC, related to soil clay content) and pH 
also influence the capacity of soil to immobilize lead. Using organic 
chelation as a model, the total capacity of soil to immobilize lead can 
be predicted by a linear relationship equation. Using this model to 
predict saturation capacity from CEC and pH it can be shown that a 
decrease in pH from 5.5 to 4.0 will reduce estimated soil capacity 1.5 
times, thereby increasing the concentration of available lead in soil 
water (Ref. 2).
    A number of field studies demonstrate the enhanced mobility of lead 
in soils under a range of environmental conditions. In all of these 
studies variables including pH, soil organic matter content and the 
chemical species of lead present played a significant role in 
increasing soil lead mobility. Limited data also indicate that organo 
lead compounds may be converted into water-soluble lead compounds in 
soil. Degradation products of tetramethyl and tetraethyl lead, the 
trialkyl lead oxides, are expected to be significantly more mobile in 
soils than the parent compounds (Ref. 2).
    Levels of soluble lead in surface waters depend on the pH of the 
water and the dissolved salt content. Equilibrium calculations show 
that at a pH greater than 5.4 the total solubility of lead is 
approximately 30 micrograms per liter (<greek-m>g/L) in hard water and 
approximately 500 <greek-m>g/L in soft water. In soft water, sulfate 
ions limit the lead concentration in solution through the formation of 
lead sulfate. The lead carbonates limit lead in solution at a pH 
greater than 5.4 (Ref. 29). Concentrations as high as 330 <greek-m>g/L 
could be stable in water at a pH near 6.5 and an alkalinity of about 25 
milligrams (mg) bicarbonate ion per liter. Water

[[Page 4514]]

having these properties is common in runoff areas of New York state and 
New England.
    Lead also forms complexes with organic matter in water. The organic 
matter includes humic and fulvic acids that are the primary complexing 
agents in soils and widely distributed in surface waters. The presence 
of fulvic acid in water has been shown to increase the rate of solution 
of lead sulfide 10 to 60 times (Refs. 30 and 31). At pH levels near 
neutral (i.e., about 7.0), soluble lead-fulvic acid complexes are 
present in solution. As pH levels increase, the complexes are partially 
decomposed, and lead hydroxide and carbonate are precipitated.
    At neutral pH lead generally moves from the dissolved to the 
particulate form with ultimate deposition in sediments. There is 
evidence that in anaerobic sediments, lead can undergo biological or 
chemical methylation. This process could result in the remobilization 
and reintroduction of transformed lead into the water column where it 
could be available for uptake by biota, and volatilization to the 
atmosphere. However, tetramethyl lead may be degraded in aerobic water 
before reaching the atmosphere.
    It can be concluded that many processes commonly observed in the 
environment result in the release of lead ion, which is available and 
bioavailable lead. These processes may occur in soil and aquatic 
environments with low pH and low levels of organic matter. Under these 
conditions, the solubility of lead is enhanced and in the absence of 
sorbing surfaces and colloids, lead ion can remain in solution for a 
sufficient period to be taken up by biota. Lead sorption to soil 
organic matter has been shown to be pH dependent. A decrease in soil pH 
can cause sorbed lead to desorb, and increase lead availability in soil 
water.
    A few commenters contend that bioavailability is only possible for 
released soluble metal compounds. This position is incorrect: EPA has 
concluded that metal compounds, including lead compounds, that are 
released as metal compounds that are not soluble or bioavailable may be 
converted in the environment into metal compounds that are available or 
bioavailable. Furthermore, as discussed above, a metal compound may not 
be soluble, but may, nonetheless, be bioavailable.
    Several commenters contend that EPA should consider each member of 
a metal compounds category (such as lead compounds) individually 
because the availability will vary from metal compound to metal 
compound within a category and some metal compounds will not be 
available at all.
    EPA disagrees. As discussed above in Unit VI.C.1. with respect to 
evaluating persistence for metal compound categories, the Agency 
believes that it is reasonable to evaluate metal compound categories, 
such as lead compounds, as a category rather than individually. 
Moreover, in the case of lead compounds, the bioavailability of a lead 
compound is not necessarily dependant upon the availability of lead 
from the compound. That is, the parent lead compound may be 
bioavailable as is or, if not itself bioavailable, could be converted 
in the environment into a compound that is bioavailable or from which 
lead is bioavailable. As EPA has discussed elsewhere in this preamble, 
the environmental fate assessment indicates that there are many 
conditions under which lead from lead compounds can become available in 
the environment. Further, most lead compounds provide bioavailable lead 
when ingested. In addition, regardless of the relative environmental 
availability of lead from one lead compound to another, the lead 
compounds all add to the environmental loading of lead. Thus, even if 
under the same environmental conditions the lead from compound A is 10 
times less available than the lead from compound B, compound A would 
introduce the same amount of available lead if its releases are 10 
times greater. If lead compounds are evaluated individually based on 
relative environmental availability then the additive effect of the 
loading of lead from these compounds would be ignored.
    Two commenters criticize EPA for not using the latest tools for 
assessing the availability of metals, including those tools in which 
the Agency was or is involved with developing. These commenters mention 
several Agency efforts that pertain to availability and the assessment 
of metals. These include the Environmental Sediment Guidelines and the 
Biotic Ligand Model development for the Water Quality Criteria.
    The environmental processes that determine the complexation, 
speciation, and ultimately the availability of lead in the environment 
have been considered and addressed elsewhere in this preamble. In 
conducting its assessment of the availability of lead in the 
environment, EPA reviewed the available documentation on both the 
simultaneously extracted metals/acid volatile sulfide (SEM/AVS) 
methodology and the Biotic Ligand Model (BLM). EPA believes that the 
SEM/AVS methodology as applied to the Environmental Sediment 
Guidelines, and the BLM as applied to water quality criteria show great 
promise for use in conducting site-specific assessments of those metals 
for which it has been validated. However, to date neither the SEM/AVS 
methodology nor the BLM have been validated for lead, nor have the 
substantive technical comments provided by the EPA Science Advisory 
Board been incorporated into these approaches. In addition, EPA does 
not believe that a means currently exists to incorporate these 
methodologies into the technical analysis supporting a nationally 
applied regulation such as this rulemaking. While at this stage of 
their development these methods may be useful in site-specific 
assessments, they cannot be applied to support national Agency programs 
such as the TRI Program because of the variability in environmental 
conditions throughout the United States. On the other hand, the PBT 
methodology, as used by EPA in the characterization of lead as a PBT 
chemical, can be used to provide technical support to national 
regulatory programs such as the TRI Program because this methodology 
incorporates the environmental processes that determine the 
complexation, speciation, and the availability of lead in the 
environment, but does not require site-specific input. EPA believes 
that the PBT model is an appropriate methodology for assessing the 
persistence of metals, including lead.
    3. What comments did EPA receive on the bioaccumulation of metals 
and metal compounds? Numerous commenters suggest that for metals and 
metal compounds bioaccumulation is not a relevant endpoint of concern. 
They contend that for metals and metal compounds: (1) Bioaccumulation 
is mitigated by environmental factors; (2) that metals and metals 
compounds are often essential nutrients and thus organisms have 
developed mechanisms to control their accumulation; (3) that BCF values 
for metals are dependent upon the concentration of the metal; and (4) 
that metals do not bioaccumulate at the concentration levels associated 
with toxicity. As discussed in detail in the following comment 
responses, EPA does not believe that any of the issues raised by the 
commenters call into question EPA's scientific and policy reasons for 
considering bioaccumulation for lead and lead compounds. Not all metals 
are essential nutrients and even those that are can be accumulated to 
unsafe levels. In particular, lead is not an essential nutrient. While 
some metal BCF values

[[Page 4515]]

vary with metal concentration this does not change the fact that the 
metals do bioaccumulate. In addition, bioaccumulation does not need to 
occur at concentrations that cause toxicity to be of concern, and in 
fact testing of bioaccumulation should not be conducted at 
concentrations that are detrimental to the test organism. Moreover, 
where there is extensive human data showing significant bioaccumulation 
of a listed toxic chemical, such as here, the bioaccumlation of the 
metal is obviously of concern. Therefore, EPA believes that 
bioaccumulation potential is a relevant endpoint of concern for metals, 
especially for lead and lead compounds.
    Several commenters contend that the extent to which a metal 
bioaccumulates in aquatic organisms is dependent upon the metal's 
concentration in the aqueous habitat of the organism. Specifically, 
this commenter states that the BAF or BCF of a substance is inversely 
related to its concentration in the surrounding aqueous medium: that 
is, BAFs and BCFs become larger as the external concentration of the 
substance decreases. Thus, according to the commenter, because a 
metal's BCF or BAF value in a given aquatic organism will vary 
depending upon concentration, a single BAF or BCF value cannot be used 
to define whether a metal bioaccumulates. In effect the commenter is 
disagreeing with EPA's definition of BCF and BAF since the definitions 
do not require that all concentrations of the chemical result in the 
same BCF or BAF.
    The Agency is in general agreement with the commenters' position 
that for a substance that bioaccumulates in aquatic species the degree 
to which it does so (i.e., the BAF and BCF of the substance) is related 
in part to the external concentration of the substance. The Agency also 
believes, however, that external concentration is not the only factor 
that influences bioaccumulation. As discussed previously, the 
propensity of a substance to bioaccumulate in a species depends largely 
upon the pharmacokinetics of the substance in that species. For further 
discussion on pharmacokinetics and bioavailability and bioconcentration 
see Unit VI.C.2.
    In addition, the Agency believes that when analyzing test data, the 
conclusion that bioaccumulation decreases as external concentration of 
a substance increases may be erroneous. It is quite possible that as 
the concentration of the test substance is increased, biochemical 
changes that are precursor events to toxicity are initiated. While the 
increased concentration may not be sufficient to cause death to the 
organism, the initiation of the precursor events may cause a stasis in 
cell growth or function, and interfere with the organism's ability to 
absorb the metal. In a species where this is the case, it would 
therefore incorrectly appear that the bioaccumulation of the metal 
decreases as external concentrations increase. Thus, the Agency is in 
general agreement with the commenter's position that, for a substance 
that bioaccumulates in aquatic species, the degree to which it does so 
is related to the external concentration of the substance. The Agency, 
however, does not agree that the relationship for metal is always truly 
inversely related: i.e., that as external concentration increases 
bioaccumulation decreases. This is not a general phenomenon for all 
metals and metal compounds in all organisms as suggested by the 
commenter.
    When discussing BCF and BAF values, distinction needs to be made 
between BAF or BCF values that are measured in a laboratory from those 
that are measured in an actual environmental setting. The Agency's 
definition of BCF and BAF (64 FR 42229) pertain to determinations of 
BAF and BCF under controlled experimental conditions where exposure of 
the aquatic species to the chemical is kept relatively constant (i.e., 
external concentration of the substance remains relatively constant). 
Thus, assays performed in laboratories to determine BAFs and BCFs are 
conducted under controlled conditions, and any sources of variability 
in conditions are minimized or eliminated. In a laboratory assay the 
test concentration is usually set at some percentage below the acute 
LC<INF>50</INF> (the concentration lethal to 50% of the test organisms 
following acute exposure); often \1/10\ of the LC<INF>50</INF> of the 
metal is used. While there is no reason BCF tests cannot be conducted 
at other concentrations of the test chemical, it would serve no 
scientific purpose to use concentrations at which the test organism 
becomes stressed or dies before the test assay is completed or before 
the organism has the opportunity to bioaccumulate the test chemical. In 
an actual environmental setting, however, conditions can be variable. 
No commenter to this rule provided scientific data showing that these 
BCF values would not be found in the environment. Consequently, EPA 
believes that appropriately conducted bioaccumulation tests conducted 
at even at one concentration of lead are valid indicators of the 
potential for lead to bioaccumulate.
    Two commenters claim that EPA dismisses the notion that 
bioavailable metals are often intentionally bioaccumulated as 
beneficial nutrients or are otherwise safely metabolized by plants and 
animals through biological mechanisms. One of the commenters states 
that while metals can bioaccumulate, the manner and rate at which they 
do so varies based upon the nutritional needs of the organism, external 
concentration of the metal, and speciation of the metal. The commenter 
also states that the bioaccumulation of metals is fundamentally 
different than the process by which organic compounds bioaccumulate.
    EPA acknowledges that some metals are nutrients in some organisms, 
including humans, or are otherwise necessary for the subsistence of 
organisms. Thus, some metals need to be bioaccumulated by the organism. 
Clearly, such metals need to be bioavailable in the organisms that 
require these metals. As discussed in greater detail elsewhere in this 
document and as alluded to by one of the commenters, in many organisms 
the absorption or uptake of metals across cell membranes involves 
active (i.e., energy-requiring) processes, whereas absorption or uptake 
of organic substances is usually the result of passive diffusion across 
cell membranes. Active transport processes give the organism some 
ability to regulate the uptake of metals. It is also important to note 
that active transport across cell membranes is not the only means by 
which a metal can be absorbed. Organometallic substances, for example, 
are often absorbed by passive diffusion. Metals and metal containing 
substances may also be taken up by organisms through phagocytic 
processes. In addition, as one of the commenters states, metal 
speciation and concentration are factors that can influence uptake of 
metals into an organism.
    While active transport processes are involved with the uptake of 
metals needed by the organisms, these processes do not always 
discriminate those metals that are needed by the organism from those 
metals that are harmful to the organism. Thus, organisms also have the 
ability to take up or absorb metals that are not nutrients and that are 
not necessary for subsistence. Thus, the processes that organisms use 
to absorb or take up needed metals do not necessarily prohibit or 
protect them from taking up toxic metals. In addition, even needed 
metals can be toxic to the organism if over exposure occurs. It is well 
established that metals that are not needed by an organism can be taken 
up by the organism, and bioaccumulated by the organism. lead and 
mercury, for

[[Page 4516]]

example, are not known to be essential metals in any species. Yet the 
uptake and bioaccumulation of these metals by organisms, including 
humans, is well established. EPA has therefore determined, insofar as 
commenters are suggesting that EPA consider the nutrient value of 
metals in this rulemaking, that such comments are irrelevant because 
lead has no known nutritive value to any species. The results of the 
studies investigating the bioconcentration of lead and lead compounds 
in aquatic organisms summarized in Table 1 (64 FR 42230) of the 
proposed lead rule and the table in Reference 10 of the proposed rule 
show that lead is taken up and bioaccumulated by many different aquatic 
organisms. Also, as discussed in Unit VI.D.3., EPA's fish advisory data 
base demonstrates that many species of fish and shellfish from various 
aquatic environments in different regions of the country contain lead 
(see http://fish.rti.org) indicating that fish and shellfish 
bioaccumulate lead under realistic environmental conditions.
    Two commenters stated that bioaccumulation of metals does not 
necessarily indicate the presence of, or a potential for adverse 
effects. At the outset, EPA stresses that lead and lead compounds are 
EPCRA section 313 listed toxic chemicals. Therefore, as stated in the 
proposed rule and elsewhere in this preamble, the toxicity of lead and 
lead compounds is not at issue in this rulemaking. These commenters 
state that bioaccumulation of a substance is not an indicator of 
hazard, and should not be used as a hazard assessment criterion.
    The Agency agrees that the ability of a substance to bioaccumulate 
does not by itself necessarily indicate the presence of, or potential 
for adverse effects. The Agency believes, however, that the concept of 
bioaccumulation is relevant to the hazard characterization of metals 
for the same reasons that it is relevant to the hazard characterization 
of organic substances: that low-level or sub-toxic exposures to a toxic 
substance that bioaccumulates could eventually lead to exposures of 
concern in the organism that bioaccumulates it or increased exposure 
potential for predator species. The Agency would also like to emphasize 
that while bioaccumulation of lead in a given aquatic organism may not 
necessarily be toxic to the organism, the accumulated lead may serve as 
a source of lead exposure and toxicity to predator species, including 
humans.
    Thus, the high bioaccumulation potential of lead, an EPCRA section 
313 listed toxic chemical, within an organism is anticipated to 
contribute a greater total body burden relative to a chemical with 
lower bioaccumulation potential, thereby increasing any toxicity to the 
organism. High bioaccumulation also increases lead exposure to other 
organisms that are predators of the organism that has accumulated the 
lead.
    4.What comments did EPA receive on the relationship of its 
persistence and bioaccumulation criteria to international criteria? Two 
commenters claim that numerous international organizations such as the 
Organization for Economic Cooperation and Development (OECD) have 
approached the classification of PBT chemicals in a manner that calls 
into question EPA's use of persistence and bioaccumulation criteria for 
accurately identifying the human and environmental health hazards of 
metals. One of the commenters claims that the OECD Advisory Group on 
Harmonization of Classification and Labeling (which includes EPA 
participants) has made the following conclusion: ``...For inorganic 
compounds and metals, the concept of degradability as applied to 
organic compounds has limited or no meaning. Rather, the substance may 
be transformed by normal environmental processes to either increase or 
decrease the bioavailability of the toxic species.'' The commenter 
recommends that EPA reconsider its characterization of lead as a PBT 
chemical because, in the opinion of the commenter, there is a lack of 
scientific support for assessing a metal's PBT characteristics to 
determine its potential hazard to human health and the environment.
    The Agency believes the commenter has misunderstood OECD's position 
on the applicability of general PBT criteria to metals. The quote is 
taken from the OECD document entitled Harmonized Integrated Hazard 
Classification System for Human Health and Environmental Effects of 
Chemical Substances. (Ref. 32) The pronouncements on metals are 
contained in paragraphs 22 and 23 of that document. Paragraph 22 reads 
as follows:
    For inorganic compounds and metals, the concept of degradability as 
applied to organic compounds has limited or no meaning. Rather the 
substance may be transformed by normal environmental processes to 
either increase or decrease the bioavailability of the toxic species. 
Equally, the use of bioaccumulation data should be treated with care. 
Specific guidance will be [but has not yet been] provided on how these 
data for such materials may be used in meeting the requirements of the 
classification criteria.
    By ``degradability as applied to organic compounds'' OECD means 
molecular degradation, most often by microbial degradation and/or 
hydrolysis or other abiotic processes, to progressively simpler organic 
chemical structures, leading eventually to inorganic substances like 
carbon dioxide and water. It is important to note that paragraph 22 
does not in any way suggest that metals are not persistent. Moreover, 
it does not suggest that OECD hazard classification criteria cannot be 
applied to metals, only that ``care'' (e.g., professional judgment) is 
required in the interpretation of data relative to the classification 
criteria. In fact, EPA agrees that in order for a metal to 
bioaccumulate in an organism it must either be environmentally 
available or bioavailable. In response to the allegations that lead is 
not environmentally available, as part of the proposed rule, the Agency 
analyzed information on the environmental fate of lead, and, as noted 
above, determined that lead has the potential to become available from 
lead compounds under commonly encountered environmental conditions. In 
addition, as explained in Unit VI.D.3, EPA determined that lead and 
lead compounds are bioavailable. Therefore, the Agency's assessment of 
lead as a PBT chemical is consistent with the OECD's intent.
    EPA does not interpret the above quote to indicate that OECD's 
position is that its or any PBT chemical criteria are not applicable to 
lead. As the commenter correctly states, EPA is a member of the OECD 
Advisory Group on Harmonization of Classification and Labeling. OECD 
does not recommend that metals and metal compounds be excluded from 
consideration as PBT chemicals, as the commenter implies. More 
specifically, OECD has not concluded that metals and metal compounds 
have no potential to bioaccumulate because they are never released as 
bioavailable compounds; or cannot be converted to bioavailable 
compounds under any foreseeable circumstances. On the contrary, EPA 
believes that the preceding language indicates that OECD's position is 
that any substance judged to be potentially bioavailable, whether 
organic or inorganic, should not be excluded as a candidate from some 
form of regulatory action. As discussed in Units VI.C.2. and VI.D.1., 
it is realistic to expect that, in general, released metals such as 
lead can encounter conditions in which they are (or can become) 
available at levels sufficient to bioaccumulate. Therefore, the 
Agency's use of the PBT criteria in its assessment of lead is 
consistent with

[[Page 4517]]

OECD's position on the general applicability of PBT criteria to metals.
    5.What comments did EPA receive on its metals policy? Some 
commenters contend that EPA should not consider all members of the lead 
compounds category to be PBT chemicals because availability and 
bioavailability of the lead portion will vary among the compounds. 
These commenters further state that the toxicity can only be evaluated 
on a compound-by-compound basis and is dependent on bioavailability.
    Members within the lead compounds category listed on the EPCRA 
section 313 list of toxic chemicals have a common moiety that bestows 
toxicity, i.e., lead. Consequently, it is reasonable to anticipate that 
once released into the environment: (1)The metal moiety in each member 
of the category will become available as a result of abiotic and/or 
biotic processes or (2) each member of the category will either be 
bioavailable or will convert into a compound that is bioavailable. For 
example, different inorganic lead compounds that are released into 
acidic surface waters will result in the formation of similar soluble 
inorganic lead compounds. Variation in the level of availability or 
bioavailability does not negate the consistency of effect across the 
members of the category.
    EPA would like to remind the commenters that a mechanism already 
exists under EPCRA section 313 to address concerns for any metal 
compound for which the data show that the metal can never become 
available. Thus, the issue of availability, which is broader than the 
issue of a compound's potential to bioaccumulate, was addressed 
previously for EPCRA section 313 chemical assessments through EPA's 
policy and guidance concerning petitions to delist individual members 
of the metal compound categories listed under EPCRA section 313 (May 
23, 1991, 56 FR 23703). If a petitioner has information demonstrating 
that a particular lead compound does not cause toxicity as the intact 
lead compound, and will not cause lead to be available in the 
environment to express its toxicity, they can submit a petition 
pursuant to EPCRA section 313(e)(1) to delete that specific lead 
compound from the EPCRA section 313 list of toxic chemicals. Under the 
metals policy EPA considers whether the metal from a metal compound can 
ever become bioavailable under abiotic or biotic conditions. An 
assessment of the availability and bioavailability of a lead compound 
would include processes such as: hydrolysis at various pHs; 
solubilization in the environment at various pHs; photolysis; aerobic 
transformations (both abiotic and biotic); anaerobic transformations 
(both abiotic and biotic); bioavailability when the compound is 
ingested (solubilization in and/or absorption from the gastrointestinal 
tract and solubilization in various organs); and bioavailability when 
the material is inhaled (solubilization in and/or absorption from 
lungs, especially taking into account the likelihood that the compound 
will lodge in the lungs and be converted a soluble compound by the 
lung's defense mechanism).
    If the commenters have information demonstrating that a particular 
lead compound does not cause toxicity as the intact lead compound, and 
will not cause lead to be available in the environment to express the 
toxicity of the metal, the commenters can submit a petition pursuant to 
EPCRA section 313(e)(1) to delete that specific lead compound from the 
EPCRA section 313 list of toxic chemicals. EPA would address such a 
petition in accordance with the Agency's longstanding stated policy and 
guidance concerning petitions to delist individual members of the metal 
compounds categories (May 23, 1991, 56 FR 23703).
    6.What comments did EPA receive that pertain to natural vs. 
industrially produced lead and lead compounds? Some commenters contend 
that natural forms of lead, as opposed to industrially produced lead 
compounds, should not be classified as PBT chemicals. Other commenters 
state that because lead occurs naturally, industrial activities 
involving lead do not change the total amount of lead in the earth: 
these activities only affect the form and location of the lead in the 
environment. These commenters believe that the forms of lead that are 
produced by industrial activity tend to be more hazardous and should be 
regulated more strictly than the natural forms, such as trace amounts 
of lead in natural minerals.
    EPA disagrees that natural lead compounds should be treated 
differently than industrially produced lead compounds. While the 
comment was made specifically for lead it is general to all metals and 
metal compounds. Both naturally occurring and industrially produced 
lead and lead compounds, meet the persistence and bioaccumulation 
criteria. EPA's analysis of the environmental fate of lead demonstrates 
that it is reasonable to anticipate that under environmental conditions 
lead can become available from lead compounds, and that whether lead or 
lead compounds are obtained naturally or produced industrially does not 
change the potential for availability of lead. Whether a chemical comes 
directly from the ground or from a manufacturing plant will not affect 
whether the chemical is toxic, persistent, and bioaccumulative. These 
are the result of the inherent properties of the chemical, not from 
their origin (all other things being equal).
    The Agency recognizes that lead and certain lead compounds occur 
naturally. EPA agrees that industrial activities involving lead do not 
change the total amount of lead in the earth, and that industrial 
activities involving lead only affect the type of lead compound and its 
location in the environment. The Agency believes, however, that while 
industrial activities do not increase the total quantity of lead in the 
earth, industrial activities transport lead and lead compounds from one 
environment to another environment in which the likelihood of exposure 
to lead in aquatic and terrestrial species, and humans is increased. As 
discussed in the PBT rulemaking (64 FR 688-729), environmental 
conditions can vary greatly among geographic locations, even those that 
are in close proximity to one another. There may be certain 
geographical areas in which the environmental conditions are such that 
lead availability from a naturally occurring lead compound may be equal 
to or greater than that from an industrially produced lead compound.

D.What Comments Did EPA Receive Concerning the Persistence and 
Bioaccumulation of Lead and Lead Compounds?

    In the proposed rule to lower the thresholds of lead and lead 
compounds, EPA discussed its scientific basis for preliminarily 
characterizing lead and all lead compounds as highly persistent and 
highly bioaccumulative. To summarize, the data on lead's persistence in 
the environment, the observed high bioaccumulation values in aquatic 
organisms, and lead's ability to accumulate in humans were the basis 
for EPA's preliminary conclusion that lead and lead compounds are 
highly persistent and highly bioaccumulative. EPA has also evaluated 
the bioavailability of lead and lead compounds and has concluded that 
lead is bioavailable. In the proposed rule the Agency specifically 
requested public comment on its discussion of the scientific 
information concerning: (1) The fate, transport and availability of 
lead in the environment and how this information should be considered 
in classifying lead as a PBT chemical (Unit V.A.); (2) the 
bioaccumulation of lead in aquatic organisms, and how this

[[Page 4518]]

information should be evaluated in assessing the bioaccumulative 
potential of lead and lead compounds (Unit V.B.); (3) the 
bioaccumulation of lead in humans, and how this information should be 
considered in classifying lead and lead compounds as highly 
bioaccumulative (Unit V.C.); and (4) abiotic factors (e.g. soil 
chemistry; pH; water hardness; presence of organic matter in aqueous 
media) that can diminish the bioavailability of lead in aquatic 
species.
    The Agency received many comments regarding EPA's technical basis 
for preliminarily characterizing lead and lead compounds as highly 
persistent, and highly bioaccumulative. These comments were extensively 
reviewed and considered by the Agency in finalizing the rule. While 
some of the commenters agreed with the Agency's characterization of 
lead and lead compounds as highly persistent and highly 
bioaccumulative, the majority of the commenters disagreed. Most of the 
comments were similar in content, and pertained to general or specific 
issues dealing with persistence, bioaccumulation and toxicity, as well 
as EPA's use of persistence and bioaccumulation data pertaining to lead 
and lead compounds in characterizing these chemicals as PBT substances. 
Lead and lead compounds are included on the EPCRA section 313 list of 
toxic chemicals. EPA is not responding to comments on the toxicity of 
lead and lead compounds, because their inclusion on the EPCRA section 
313 list of toxic chemicals is not at issue in this rulemaking. After 
consideration of all comments submitted in response to the proposed 
lead rule, EPA concludes that lead is highly persistent and, at the 
least, bioaccumulative and defers its determination as to whether lead 
is highly bioaccumulative. An explanation for EPA's conclusion that 
lead is at least bioaccumulative is provided below. The basis for EPA's 
conclusion that lead is highly persistent is provided elsewhere.
    In the PBT chemical rulemaking, EPA described bioaccumulation as 
``the process by which organisms may accumulate chemical substances in 
their bodies'' (64 FR 703) and defined the term as the ``net 
accumulation of a substance by an organism as a result of uptake from 
all environmental sources.'' (64 FR 703) EPA has a concern for those 
toxic chemicals that are bioaccumulative and a particular concern for 
that subset of PBT chemicals that are highly bioaccumulative.
    There are extensive, high quality human data (64 FR at 42230-31) 
that clearly indicate that lead and lead compounds bioaccumulate in 
humans, i.e., humans accumulate lead as a result of uptake from 
environmental sources. These data include bioaccumulation data on a 
number of subpopulations of humans, such as children, pregnant women, 
postmenopausal women, and men. Therefore, these human data support 
EPA's conclusion, as discussed below, that lead and lead compounds are 
bioaccumulative. EPA believes that these data would tend to support a 
finding that lead is also highly bioaccumulative because (1) the data 
are human data and (2) these data conclusively demonstrate that lead 
bioaccumulates in humans. EPA believes that these two factors are 
relevant to a determination that lead and lead compounds are highly 
bioaccumulative because human data are generally more compelling than 
animal data, particularly where there are multiple, high quality 
studies on a broad range of individuals. Thus, these data are 
sufficiently conclusive that there is no question that lead and lead 
compounds bioaccumulate in humans.
    While evaluation of these data might affect EPA's conclusion as to 
whether lead and lead compounds are highly bioaccumulative, EPA 
recognizes that it did not clearly articulate in the proposed rule how 
human data would be used to distinguish between bioaccumulative and 
highly bioaccumulative chemicals. Because of this, EPA is deferring at 
this time the classification of lead and lead compounds as highly 
bioaccumulative solely on the basis of the extensive human data.
    A number of industry commenters have contended that BCFs and BAFs 
measured for metals (including lead), and in particular essential 
elements, are not representative of the potential of these substances 
to bioaccumulate. They claim that the variability of the measured BCFs/
BAFs with changing water concentration of the chemical makes it 
difficult to determine the most representative BCF/BAF value for a 
particular species. Specifically, these commenters contend that there 
is an inverse relationship between the measured BCF/BAF values and 
water concentration. Some commenters assert that only the values 
measured at higher water concentrations should be used, i.e., the lower 
BCF/BAF values. Other commenters contend that BCFs and BAFs are not 
meaningful measures for the bioaccumulation of metals and, therefore, 
cannot be used.
    EPA disagrees that this is the best characterization of the 
bioaccumulation data for metals, including lead, in aquatic species. 
While this type of relationship may exist for some species and/or some 
metals, for other species and/or metals other relationships are 
observed: (1) Constant BCFs/BAFs with increasing water concentration; 
(2) increasing BCFs/BAFs with increasing water concentration; and (3) 
varying BCFs/BAFs values with constant water concentration.
    EPA disagrees that the BCF/BAF data cannot be used to determine the 
potential for lead, which is not an essential element, to 
bioaccumulate. EPA recognizes that some data suggest that the 
relationship between bioaccumulation and water concentration of lead 
could be characterized as inverse for some organisms, such as fish, 
algae, and phytoplankton. Such a characterization, however, is 
incorrect for invertebrates such as snails and bivalves because there 
is little variation in BCF value with changing water concentration for 
these species. Further, EPA does not believe that even where the data 
suggest an inverse relationship, this precludes the use of BCFs and 
BAFs in assessing the bioaccumulative potential of lead. EPA notes that 
even for some species in which an inverse relationship is suggested 
(e.g., algae and phytoplankton), if EPA were to use the BCF or BAF at 
the highest water concentration measured (i.e., the lowest measured 
BCF/BAF value) the BCF/BAF values remain over 5,000.
    EPA has determined that the data on oysters, snails, algae, 
phytoplankton, and blue mussels, as well as the human data, clearly 
support a conclusion that lead and lead compounds are bioaccumulative, 
and also believes that this information tends to support a finding that 
lead is highly bioaccumulative. However, during the public comment 
period and during inter-Agency review, questions were raised 
challenging the sufficiency of the data to support the conclusion that 
lead and lead compounds are highly bioaccumulative. Before determining 
whether lead and lead compounds are highly bioaccumulative, EPA 
believes that it would be appropriate to seek external scientific peer 
review from its Science Advisory Board, and EPA intends to do so. The 
external peer review would address the question of whether lead and 
lead compounds should be classified as highly bioaccumulative. The 
external peer review would address the issue of how lead and other, as 
yet unclassified, metals such as cadmium, should be evaluated using the 
PBT chemical framework, including which types of data (and which 
species) are most suitable for these determinations. After

[[Page 4519]]

the completion of the external scientific peer review, EPA will 
consider and take appropriate action, which could include 
characterizing lead and lead compounds as highly bioaccumulative and 
lowering the reporting thresholds for lead and lead compounds to 10 
pounds. Therefore, at this time, EPA concludes that lead is, at the 
least, bioaccumulative and defers its determination as to whether lead 
is highly bioaccumulative until further review.
    1. What comments did EPA receive on the environmental fate of lead 
and lead compounds? In the lead proposed rule (64 FR 42227) the Agency 
provided a qualitative environmental fate assessment of lead and lead 
compounds. Qualitative environmental fate assessments are generally 
part of a hazard assessment for a chemical. The qualitative 
environmental fate assessment was not developed, nor was it intended, 
to be part of an exposure assessment or risk assessment.
    An environmental fate assessment for a metal and metal compounds, 
such as lead and lead compounds, describes the physical, chemical, and 
biological processes acting upon the metal and metal compound in the 
environment and the result of these processes. The environmental fate 
of a metal or metal compound varies depending on the environmental 
conditions and the physical/chemical properties of the metal in 
question.
    The Agency received many comments on its assessment of the 
environmental fate of lead and lead compounds and the influence of 
environmental fate on the environmental availability of lead and lead 
compounds. Commenters contend that normal environmental processes 
control the availability of lead and lead compounds in water, soil and 
sediments and concluded that under most environmental conditions lead 
from lead and lead compounds would not be available for uptake by 
organisms due to processes including the pH dependent formation and 
precipitation of insoluble lead compounds in surface waters, and 
sorption of lead to organic matter and inorganic constituents in soil, 
surface waters and sediments.
    EPA disagrees with these commenters and concludes that processes 
commonly observed in the environment can result in the formation of 
available lead where it can be bioaccumulated by organisms. EPA 
believes that these processes may occur in soil environments with low 
pH and low levels of clay and organic matter. Lead sorption to soils 
has been shown to be pH dependent. Decreasing pH can result in 
increasing concentrations of lead in soil water with greater 
availability for uptake by biota. In acidic aquatic environments, low 
levels of suspended solids and dissolved organic matter can result in 
increased levels of lead ion in solution where it can be taken up by 
biota.
    One commenter believes that the environmental fate data that EPA 
used and cites in the proposed rule falls short of what is necessary 
for a scientifically valid approach to assessing the transformation, 
specification, and availability of lead in the environment. The 
commenter argues that the data cited by EPA indicate that very little 
of the lead released to the environment is likely to be present in a 
``bioavailable form'' (i.e., EPA concluded that less than 1% of lead in 
soil may be water soluble).
    EPA disagrees with the commenter's characterization of EPA's 
assessment of the environmental fate of lead and lead compounds. EPA 
asserts that it used reliable data from a variety of credible sources 
in concluding that lead can be available for uptake by organisms in the 
environment and that lead is environmentally available. EPA refers the 
commenter to the discussions of the transformation, speciation, 
availability and bioavailability of lead in the environment provided in 
The Environmental Fate of Lead and Lead Compounds (Ref. 2) and 
elsewhere in the RTC document for this final rule (Ref. 1). EPA 
disagrees with the commenter's interpretation of the statement ``EPA 
concludes that less than 1% of lead in soil may be water soluble'' to 
mean or indicate that very little of the lead released into the 
environment is likely to be present in a ``bioavailable form''. Simple 
water solubility is not a prerequisite for a metal to become available 
from a metal compound. It is well established that certain 
environmental conditions can increase the solubility of a metal 
compound. Further, as discussed in Unit VI.C.2. of this preamble and in 
the RTC document (Ref. 1), availability of a metal is not a 
prerequisite for its bioavailability. Metals may be bioavailable from 
metal compounds or metal complexes that are not water soluble or in 
which the metal is not otherwise available. A classic example that 
illustrates these points are the well documented incidents of 
childrens' exposure to lead from consumption of soil that contains 
lead. While less than 1% of lead in soil is typically present as a lead 
compound that is water soluble (i.e., more than 99% is present as lead 
compounds that are water insoluble or bound to soils), the lead in 
soils is still bioavailable in humans.
    EPA has concluded that lead released to the environment, whether 
under conditions where it is available or not, can reasonably be 
expected to be bioavailable in organisms. EPA's statement ``that less 
than 1% of lead in soil may be water soluble'' should not be 
interpreted to mean that the levels of lead in soils that is available 
are inconsequential or negligible. On the contrary, because exposure to 
even low levels of lead are expected to result in its bioaccumulation 
in many organisms, these levels are still of concern. It should be 
noted that if 1 percent of soil lead is soluble (i.e., available), this 
would mean that levels as high as 200 parts per billion (ppb) could be 
found in soil water (lead is present in many soils at 20 parts per 
million (Ref. 2) and one percent of this is 200 ppb.)
    One commenter believes that the bioavailability of lead and lead 
compounds is only prevalent in those situations in which an organism 
would be exposed to continuous, localized influxes of lead compounds, 
such as near a lead smelter or a highway. The commenter believes that 
the proximity to sources of lead, such as smelters or highways 
(influenced by use of leaded fuels), is a prerequisite to high 
concentrations of the metal in the environment, and thus its potential 
to bioaccumulate. The commenter cites studies that provide data that 
show high levels of lead in waters and soils that are in close 
proximity to sources of lead releases (e.g., smelters, vehicular 
exhaust), and bioaccumulated lead in freshwater algae, invertebrates, 
and fish collected near industrialized areas, ponds with high numbers 
of lead shot, urban areas, lead mines and tailings ponds. The commenter 
states that although lead may be considered ubiquitous in the 
environment, its ecological impacts would appear to be significantly 
influenced by the proximity to sources of lead releases and the public 
should be aware of this. While the commenter used the term 
bioavailability, based on the context of the comment, EPA believes the 
commenter used the term interchangeably with the term environmental 
availability.
    While the concentrations of lead in the environment are more likely 
to be higher in areas that are in close proximity to facilities that 
manufacture, process, or otherwise use lead and/or lead compounds, EPA 
disagrees with the commenter's contention that the availability of lead 
is only possible in such areas. EPA does not agree with the commenter's 
position that in order to be exposed to lead an organism needs to be in 
close proximity to points where lead

[[Page 4520]]

is released into the environment. As discussed in Unit V.A. of the 
proposed rule (64 FR 42227), and in The Environmental Fate of Lead and 
Lead Compounds (Ref. 2) many factors influence the mobility and 
disposition of lead in the environment. Under many environmental 
conditions lead may become mobile rather than remain stationary. 
Depending upon prevailing conditions and the method of environmental 
release, lead may travel within environmental media to areas that are 
not in close proximity to the point of release. Hence, EPA believes 
that the presence of lead in the environment, and therewith its 
availability, is not confined to the areas where lead is released from 
anthropogenic sources. In addition, any release of lead is important to 
local communities, because of lead's persistence and bioaccumulative 
properties. Although EPA disagrees with the commenter's conclusions, 
the commenter's statement that the ecological impacts of lead are 
influenced by the nearness to a source of release still provides 
support for the actions that EPA is taking in this rulemaking.
    a. What comments did EPA receive on the abiotic factors that may 
affect the environmental availability of lead? Several commenters 
stated that EPA either did not, or should have considered speciation, 
transformation and bioavailability in its assessment of the persistence 
of lead and lead compounds. Some of the commenters contend that in most 
environments lead is either not available or is transformed into forms 
that are less available. A number of the commenters claimed that the 
environmental conditions in which lead is mobile or available are rare.
    EPA disagrees with the commenters claim that the Agency did not 
consider speciation, transformation and bioavailability in its 
characterization of lead and lead compounds as PBT chemicals. As 
discussed in detail in: Unit V. of the proposed lead rule (64 FR 42222-
42243); in The Environmental Fate of Lead and Lead Compounds (Ref. 2); 
elsewhere in this preamble; and in the RTC document (Ref. 1), EPA 
performed a comprehensive assessment of the environmental fate of lead. 
The environmental fate assessment embodied an analysis of the 
environmental variables that affect speciation, transformation, and the 
availability of lead. These environmental variables include: pH; redox 
conditions; water hardness; dissolved organic carbon content; and soil 
properties including cation exchange capacity, organic carbon content, 
iron and manganese oxide and phosphorus content. As discussed in Unit 
VI.D.3., EPA has evaluated the bioavailability of lead and lead 
compounds and has concluded that lead is bioavailable. From its 
analysis of the environmental fate of lead, EPA concluded that 
environmental conditions exist in the United States in which lead may 
become available or that can increase the availability of lead, even 
from compounds in which lead, as released into the environment, is not 
available. From its analysis of the bioavailability of lead, EPA 
concluded that lead is bioavailable in many aquatic species, and in 
humans. EPA also concluded that lead compounds that are not available 
or bioavailable as released may be converted to lead compounds that are 
available or bioavailable. Thus, after an evaluation of the available 
data, EPA has determined that the weight of scientific evidence 
indicates that it is reasonable to conclude that lead in the 
environment will be available and/or bioavailable from lead and lead 
compounds.
    EPA disagrees with the commenters who claim that the environmental 
conditions in which lead is mobile or available for uptake are rare. As 
detailed in Unit VI.C. of this preamble and in the RTC document (Ref. 
1), EPA conducted several analyses of large databases containing 
information on the properties of rivers, streams, lakes, and soils in 
the United States, with a focus on the properties known to contribute 
to the availability of lead. Acidity is a particularly important 
determinant of lead availability: acid conditions (pH  7) increase lead 
availability. In water, the solubility and, hence, availability of lead 
increases linearly as acidity is increased (i.e., from pH 6 to 3). EPA 
determined that waters of sufficient acidity to favor lead 
availability, especially in the Mid-Atlantic region of the United 
States, are not rare. In fact, estimates indicated that almost 11,000 
kilometers of streams could have a pH of  5.5. In addition, as detailed 
elsewhere is this document, a query of EPA's STORET water quality 
database indicated that in 1998 pH values of between 5.5 and 5.1 were 
found in 52 watersheds in the United States. Finally, the commenter 
asserts that acidic soils in which lead is likely to be available are 
rare. EPA's analysis of the database of the Soil Survey Laboratory, 
National Soil Survey Center, discussed in Units VI.C.1. and VI.D.1. of 
this preamble, found more than 10,000 surface soil samples with low 
cation exchange capacity and pH values of less than 5.5.
    One commenter supports EPA's concern for cross media transport of 
chemicals, but believes that it is misleading for EPA to imply that 
lead is predisposed to find the medium in which it will be transformed 
into forms that have the ``greatest bioavailability (in) man''. The 
commenter agrees that lead cannot be destroyed but, equates this 
attribute to most elements on the periodic table.
    The commenter incorrectly asserts that EPA suggested that lead and 
lead compounds are released only to, or preferentially partitions to, 
those environments that are most favorable to enhancing availability or 
bioavailability of lead. EPA disagrees with the commenter. EPA has not 
made the claim that lead and lead compounds are released only into 
those environments where conditions are most favorable to the formation 
of the most soluble lead compounds. In EPA's discussion of the 
environmental fate of lead and lead compounds, EPA assessed the 
availability of the lead and lead compounds under a variety of 
conditions in water, sediments and soil. As discussed elsewhere, EPA 
believes that there are many environmental conditions in which lead and 
lead compounds will be available and/or bioavailable.
    b. What comments did EPA receive on the availability of lead in 
surface waters and sediments. One commenter stated that there are many 
studies that indicate that lead does not persist in soluble and 
bioavailable forms in aquatic environments. The commenter cited work 
reported by May and McKinney (Ref. 33) which, according to the 
commenter, has shown that the majority of lead entering natural waters 
will be precipitated to sediments as carbonates or hydroxides (i.e., 
will be unavailable). The commenter states that even in acidic lake 
waters, ``which according to EPA's own reports are rare'', lead can 
precipitate out of the water, and cites work by White and Driscoll 
(Ref. 34) to support this position. Another commenter states that there 
is strong evidence to suggest that under conditions where organic 
material is present in the water column of an aquatic environment, the 
organic material will act to reduce the amount of potentially soluble 
and bioavailable lead. The commenter believes that the wide 
distribution of organic matter suggests that the potential for the 
reduction of soluble lead by complexation with organic material is 
high.
    EPA disagrees with the argument that soluble and/or bioavailable 
lead compounds are irreversibly transformed into insoluble and un-
bioavailable lead compounds. EPA discusses below and

[[Page 4521]]

elsewhere that many lead compounds that form as a result of conditions 
in the aquatic environment (e.g., lead-organic matter complexes, 
inorganic precipitates, carbonates and hydroxides ) are not necessarily 
permanently sequestered as a non-available lead compound, but are 
subject to processes that can result in their release back into 
solution. A review of the discussion of the fate of lead in natural 
waters in May and McKinney (Ref. 33) revealed a single sentence that 
says: ``Upon entering natural waters, most lead is precipitated to the 
sediment bed as carbonates and hydroxides.'' While this statement is 
true for some surface waters in the United States, EPA has concluded 
for the reasons discussed below and elsewhere in this preamble and in 
the RTC document (Ref. 1) that lead solubility is greater and 
precipitation as carbonate and hydroxide is less in acidic waters with 
low hardness.
    White and Driscoll (Ref. 34) observed temporal and spatial 
variations in the concentration and transport of lead in the acidic 
Darts Lake in the Adirondacks of New York. Deposition of particulate 
lead was strongly correlated with aluminum and organic carbon 
deposition. Increasing metals deposition was observed during periods of 
increasing pH. The flux of lead into the lake was related to stream 
hydrology, pH and lead concentration. Stream pH varied seasonally, with 
a steady pH of 5.1 until spring snowmelt, where pH levels dropped to a 
minimum of 4.8 in April/May. Increases in pH occurred throughout the 
summer reaching a maximum of 5.4 in August. High flow periods in the 
fall and spring were marked by increases in the concentration of 
dissolved lead in the inlet and outlet streams. Lead flux to and from 
the lake was greatest during spring and fall periods of high lead 
concentrations, elevated water discharge, and low pH. The authors 
explain that even in acidic lake water containing a variety of particle 
types, oxides and organic films may determine the surface properties of 
suspended particulate matter. The solid matrix in the lake was probably 
composed of inorganic hydrous oxides (coatings) and adsorbed or 
coprecipitated organic matter. The interaction of lead with this matrix 
appears to be pH sensitive. Changes in pH may affect lead partitioning 
between the solid and solution through a number of possible mechanisms: 
matrix formation/dissolution, sorption/desorption of organic complexes 
and inorganic complexes, and hydrogen ion exchange reactions.
    Contrary to the commenter's interpretation, EPA believes that the 
study by White and Driscoll (Ref. 34) provides evidence that even in 
the presence of dissolved organic carbon, soluble lead may be present 
in the water column of acidic waters, possibly through a process of 
sedimentation and decomposition of organic matter and/or dissolution of 
redox sensitive hydrous oxides.
    Two commenters contend that the majority of lead entering aquatic 
systems will be removed from solution and become bound to sediments 
and/or suspended particulate matter. They believe that the lead that 
partitions to sediments is not expected to be readily bioavailable. The 
commenters contend that the availability of lead in sediments is 
controlled by several physicochemical factors including pH, organic 
carbon (particulate and dissolved), iron and manganese oxyhydroxides, 
and sulfides. In aerobic sediments, the main factors that drive the 
formation of insoluble lead are particulate organic carbon and iron/
manganese oxyhydroxides. In anaerobic sediments, which represent the 
overwhelming majority of sediments, acid-volatile sulfides (AVS) are 
the main binding factor.
    The commenter contends that if the concentration of AVS is greater 
than that of lead that is simultaneously extracted from the sediments, 
the lead will not be environmentally available. Further they state that 
EPA is currently considering using this concept to derive national 
sediment quality criteria for lead and other metals such as zinc, 
cadmium, and copper. In addition, the commenter contends that although 
events such as storms or dredging may cause a re-suspension of 
sediments (thus temporarily changing the physicochemical properties of 
the sediment), several studies have shown that these events do not have 
a large impact on the binding of metals such as lead to the sediments, 
and found that no significant release of lead occurred from dredged 
sediments being suspended in waters. The commenters claim that other 
studies have shown only a small portion of metals are released from 
sediment due to re-suspension and oxidation of the sediments.
    EPA agrees that the environmental processes that determine the 
complexation, speciation, and ultimately the availability of lead in 
the environment should be considered in its present analysis and 
asserts that these have been considered. EPA believes that the AVS 
methodology shows great promise for use in conducting site-specific 
assessments of metals for which it has been validated. To date, the AVS 
methodology has not been validated for lead, nor have the generally 
favorable, albeit substantive technical comments provided by the EPA 
Science Advisory Board been incorporated into the methodology. Finally, 
EPA does not believe that a means currently exists to incorporate the 
AVS methodology into the technical analysis supporting a nationally 
applied regulation such as this rule.
    EPA disagrees with the commenter's conclusions regarding sediment-
bound metals, and the commenter's inference that once lead becomes 
bound to sediments it is no longer available. EPA has found that 
several researchers have investigated the impact of the oxidation of 
sediment constituents on the release of sediment-bound metals and found 
that metal availability can increase under these conditions. For 
example, Zhuang et al. (Ref. 35) found that the aeration of sediment 
resulted in the rapid oxidation of a major binding constituent, acid-
volatile sulfide. In experiments conducted over a 1 month duration, the 
concentration of cadmium increased 200-400 percent. The oxidation of 
AVS occurred rapidly with a concomitant decrease in pH, and the release 
of cadmium from the solid to the liquid phase continued for 
approximately 2 weeks. The authors noted that aeration of sediments 
results in only a portion of the associated cadmium, and presumably 
other toxic metals, being released to water. Sedimentary iron and 
manganese are transformed to their oxyhydroxides by the oxidation of 
sulfide. Following the formation of iron and manganese oxyhydroxide, 
the binding of cadmium is transferred towards these solid phases. 
Approximately 50% of the cadmium bound in sediments is associated with 
the extractable iron and manganese components of the sediment following 
aeration. In addition, oxidation of the sulfidic phase releases other 
metals that compete with cadmium for available binding sites. EPA 
believes that it is important to note the following from the authors' 
conclusions:
    Prediction of biological availability of metals in sediments based 
on the relationship between metal and AVS concentrations may be 
underestimated if the sediment is subject to aeration.
    Thus, experimental data exist that indicate that cadmium, and 
presumably other toxic metals including lead, bound to sediments can 
become available. The data also suggest that contrary to what the 
commenter believes, the AVS methodology does not always provide an 
accurate estimate of lead availability

[[Page 4522]]

when certain, realistic environmental conditions exist.
    Other studies demonstrated the availability of lead in aquatic 
environments. Mahoney et al. (Ref. 36) examined the partitioning of 
metals, including lead, to organic carbon in 14 different freshwater 
sediment samples. The metal sorption due to acid volatile sulfide was 
subtracted from the total sorbed metal to determine the metal bound to 
other sediment phases (primarily organic carbon). The results indicated 
that organic carbon partition coefficients for lead were reduced by a 
factor of 10 with a decrease in pH from pH 7 to pH 6. The authors fit 
the sorption data to the Langmuir model. The results were consistent 
with a surface complexation model where binding sites are occupied by 
either protons (H<SUP>+</SUP>) or metal ions. At lower pHs, the protons 
compete favorably for the sites, whereas at higher pHs where protons 
are fewer in number, free metal is removed from solution by organic 
carbon sorption. This study illustrates that in sediment water systems 
at pH values in the physiological range, lead can be available for 
uptake by organisms even in the presence of organic carbon.
    Another commenter states organic matter, using as an example humic 
acids, present in freshwater and marine sediments and in the aqueous 
phases are capable of complexing variable amounts of metals. The 
commenter states that most lead entering natural waters is sorbed onto 
organic ligands and precipitated as insoluble complexes to the 
sediments as lead carbonate and hydroxide (Ref. 37). The commenter also 
states that the lead from these complexes may be mobilized and released 
back into the water column, but only when the pH is decreased suddenly 
or the ionic composition of the water changes. The commenter claims 
that both natural soluble organics (e.g., dicarboxylic and amino acids) 
and synthetic soluble organics (e.g., ethylene diaminetetraacectic acid 
(EDTA)) act as chelators (i.e., sequestering agents) of lead, and 
reduce the toxicity of heavy metals such as lead because chelated forms 
of metals are less toxic than their free, non-complexed forms. The 
commenter cites work by Canterford and Canterford (1980), which shows 
that EDTA reduced the toxicity of lead to the diatom, Ditylum 
brightwellii.
    EPA believes that the data in Eisler (Ref. 37) cited by the 
commenter supports EPA's contention that lead can be available in the 
sediment/water environment under low pH conditions. EPA has discussed 
the role of organic matter and pH in decreasing the availability of 
lead and lead compounds in the aquatic environment elsewhere in this 
preamble (see also Ref. 2). EPA recognizes the important role of 
organic matter and pH on the availability of lead and lead compounds in 
the aquatic environment and the effect of pH on the sorptive behavior 
of organic matter. However, EPA has commented elsewhere that waters 
with low organic matter and low pH are widely distributed throughout 
the United States. EPA believes that lead can be available in such 
environments. In addition, while EPA believes that lead sorbed onto 
organic matter may be temporarily unavailable, EPA does not agree that 
lead sorbed onto organic matter is no longer bioavailable. Many aquatic 
species (e.g., mussels, fish) consume orally as part of their diet 
organic matter in their environment. Lead sorbed to organic matter may 
be bioavailable in organisms that consume the organic matter. The same 
holds true for terrestrial species. Lead sorbed to soils, for example, 
is bioavailable in humans (See Unit VI.D.2. of this preamble).
    c. What comments did EPA receive on the availability of lead in 
soils. One commenter claims that EPA's data on the fate of lead in 
terrestrial environments do not support the Agency's conclusion that 
lead is expected to be bioavailable when in terrestrial environments. 
The commenter states that EPA fails to provide information about the 
probability of the natural occurrence of the conditions that could 
result in the formation of soluble/bioavailable lead species.
    EPA believes that soils possessing properties that are conducive to 
the increased mobility of lead are by no means uncommon. In order to 
determine the extent to which soil samples collected across the United 
States possess such properties, EPA conducted a query of the database 
of the Soil Survey Laboratory (SSL), National Soil Survey Center. The 
database currently contains analytical data for more than 20,000 pedons 
of U. S. soils and about 1,100 pedons from other countries. Most of the 
data were obtained over the last 40 years. Of these, about 75 percent 
are less than 20 years old. Coverage is for all 50 states, Puerto Rico, 
Virgin Islands, Trust Territories, and some foreign nations. The search 
was designed to identify soils with a pH of less than 5.5 and a cation 
exchange capacity (CEC) of less than 10 milliequivalents (meq) /100 
grams. The results of this search identified more than 10,000 samples 
that meet the criteria.
    Many investigators have studied the speciation, mobility, and 
availability of lead in soils. The EPA concludes from this body of work 
that although lead binds to many soils, under many natural 
environmental conditions it will, or at least can be expected to be 
available for uptake by organisms. Reddy, et al. (Ref. 38) studied the 
speciation of lead in water extracts from soil samples from the Powder 
River Basin in Wyoming. Dissolved concentrations of lead were found to 
be 0.003 to 0.046 mg/L. Chemical speciation indicated that at near 
neutral pH, dissolved metal concentration in soil water extracts was 
dominated by dissolved organic carbon-metal complexes. At low pH, 
dissolved metal concentration in soil water extracts was dominated by 
free ionic oxidation states, (e.g., Pb<SUP>+2</SUP>). The results 
suggest that as soil pH decreased, the availability and mobility of 
lead ions increased due to the lead compound in which the metal is 
present in soil solutions. Wang and Benoit (Ref. 39) investigated the 
mechanisms controlling the mobility of lead in soils of a northern 
hardwood forest ecosystem. The authors observed that about 50% of total 
filtrate lead (passing through a 0.45 um filter) was found to be in the 
colloidal form below the soil surface organic layer. Colloidal lead 
concentrations in deeper horizons were less than 10% of the 
concentrations in the surface layer. Less than 10% of the dissolved 
lead was found to be complexed to organic substances. A calculated 
distribution of inorganic lead species indicated that at the pH of the 
soil solutions tested (4.0 to 4.7), free, dissolved ionic 
Pb<SUP>+2</SUP> dominated and other complexes and ligands were 
negligible. Low pH resulted in Pb<SUP>+2</SUP> desorption from soil 
solids. However, because both colloidal and dissolved lead were 
effectively removed during transport down the soil profile, mobilized 
lead from the surface organic layer was retained in lower soil 
horizons. Although this study suggests that under the conditions 
investigated, lead does not migrate to an appreciable extent through 
the soil profile, EPA believes it gives a strong indication that lead 
may be available in the acidic organic surface horizon.
    The effects of redox potential and pH on the solubility of lead in 
contaminated soil were investigated by Chuan et al. (Ref. 40). Lead was 
sparingly soluble at pH 8.0 and more soluble at pH 5.0; solubility 
increased considerably at pH 3.3. At the same pH, solubility increased 
as the redox potential decreased. However the effect of pH was more 
significant than redox

[[Page 4523]]

potential. It was proposed that lead in soil was primarily adsorbed to 
iron-manganese (Fe-Mn) oxyhydroxides and the pH dependent adsorption 
and dissolution of the Fe-Mn oxyhydroxides under reducing conditions 
controlled the solubility of lead in soil. EPA believes that the 
indication of increased lead solubility at pH 5 suggests that in many 
soils lead could be available for uptake by organisms.
    Murray et al. (Ref. 41) analyzed the distribution of lead in 
surface and subsurface soils at an outdoor shooting range in 
southeastern Michigan that had been in operation for 50 years. It was 
found that the distribution of lead in the subsurface corresponded to 
that in the surface soil horizon, suggesting that lead was mobilizing 
and migrating downward through the vadose zone. Mobilization of lead 
appeared to be occurring despite the clay-rich nature of the soils, and 
was thought to be due to the transformation of metallic lead into 
soluble lead carbonate and lead sulfate. Both compounds were found in 
crust material coating shot pellets found below a depth of about 5 cm 
at the site, thus implying a reaction between the metallic lead and the 
soil. The evidence of the apparent mobility of lead under conditions 
thought to decrease mobility further indicates that lead is available 
for uptake in soils.
    Laperche et al. (Ref. 42) studied the use of soil phosphorous 
amendments as a means of reducing the availability of lead in 
contaminated soils. In this study soil contaminated with lead was 
treated with natural and synthetic phosphorous, and the bioavailability 
of lead in plants was determined in plant uptake studies with sudax 
(Sorghum bicolor). The lead content in the shoot tissue decreased as 
the quantity of added phosphorous increased, due to the formation of 
insoluble lead phosphate compound pyromorphite. However, lead and 
phosphorus contents in the roots increased as the quantity of added 
phosphorus increased. The formation of pyromorphite on root surfaces 
was also observed. It is important to note that in the absence of 
phosphorous amendments, lead content in the shoot was 170 mg lead/kg 
dry weight, whereas with the most effective phosphorus treatment, lead 
content in the shoot was 3 mg lead/kg dry weight. This strongly 
suggests that in soils with low phosphorus content, lead can be 
available for uptake by plants.
    One commenter believes EPA does not adequately address the 
important role of cation exchange capacity of soils as it relates to 
the availability of lead and lead compounds. The commenter states that 
at pHs of 5 to 9, clays possess surfaces that are predominantly 
negative and to which charge-compensating cations are adsorbed. The 
commenter claims that these cations are not permanently bound to the 
clays and are being exchanged by other cations, including heavy metals 
such as lead, copper, and cadmium.
    EPA has discussed the effects of pH and cation exchange capacity on 
the availability of lead in soils in Unit VI.C.2. of this preamble and 
in the RTC document (Ref. 1). EPA recognizes the important role of 
cation exchange capacity of soils in the availability of lead and lead 
compounds, and the effect of pH on the sorptive behavior of clays. The 
cation exchange capacity of soils is related to the clay content of the 
soil. Soils with low clay content and low cation exchange capacity are 
common and widely distributed. EPA has concluded that lead can be 
available in such soils.
    A commenter summarized research results published by Zimdahl and 
Skogerboe (Ref. 43), and stated that the research showed that soils 
have a strong capacity to immobilize lead, and that lead tends to 
become associated with the organic fraction of soil particles. The 
commenter states that the authors concluded that this sorption is less 
likely to be affected by low pH (acidification) than would acid ion 
precipitates (carbonates, phosphates, sulfates, chlorides). The 
commenter also claims that these investigators concluded that plant 
uptake studies strongly support their conclusions about the 
immobilization of lead and its sorption to organic matter in the soil.
    EPA reviewed the publication by Zimdahl and Skogerboe (Ref. 43). In 
the discussion section of this publication the authors provide the 
following overview regarding the behavior of lead in soils:

    * * * the movement of lead in the soil profile and its ultimate 
fate may be determined by one or more of several processes. These 
depend largely on the dissolution of the lead particles in the 
ground water. The lead dissolved may be leached through the soil 
profile if it remains in a soluble form. It may be immobilized by 
soil microorganisms, precipitation, sorption or ion-exchange 
interaction with soil entities (e.g., clays) or fixation by 
materials such as organic matter. It may also be taken up by plants, 
thereby entering the food chain. ... The significance of this 
possibility is reflected in the demonstrated toxicity of lead to 
corn, beans, lettuce, and radishes in lower concentrations in 
slightly acidic soil. These and other studies suggest that lead in 
soil can reach the soil plant root interface and be taken up by 
plants.

    In their investigation of the factors controlling the mobility of 
lead in soils the authors developed a correlation function based on the 
soil properties determined to be most strongly correlated with soil 
immobilization of lead (pH and cation exchange capacity). Precipitation 
by carbonate and sorption by hydrous metal oxides appeared to be of 
secondary importance. They concluded that lead will be twice as mobile 
(i.e., available) in soil with a pH of 4.1 and a CEC of 13 meq/100 g as 
in a soil with a pH of 6.8 and a CEC of meq/100 g. EPA believes the 
findings of Zimdahl and Skogerboe do not conflict with EPA's 
environmental fate analysis of lead and lead compounds. EPA agrees that 
the authors determined that some soils have the capacity to decrease 
the mobility of lead, but equally as important, the study provided a 
means to estimate the effect that a soil's properties can have on 
decreasing its capacity to immobilize lead, thereby increasing 
availability.
    One commenter disagrees with the contention of other commenters 
that lead and lead compounds should not be considered persistent 
because when released to the soils they will not be bioavailable. The 
commenter asserts that because metals released into the environment do 
not always immediately become bound to particles, nor do they remain 
bound given pH and other changes, and because metals bound to soil 
particles are ingested by young children, there are strong reasons to 
be concerned solely about the persistence of toxic metals.
    EPA agrees with the commenter that lead released to the environment 
may not become immediately bound and that there are environmental 
conditions that will increase the availability of lead in soils. One 
example is the effect of pH on lead compounds. For example, lead when 
part of a compound which has low solubility at neutral to basic pH will 
be converted into soluble compounds when subject to acid mine drainage. 
The soluble lead compounds will be mobile and may travel through the 
environment. When these compounds experience higher pH their mobility 
will decrease and the availability will decrease. However, the 
availability in many cases will be greater than in the original lead 
compound. The lead may be part of a lead compound (e.g., carbonate) in 
which it is much more available than in the original lead compound, 
even if the pH is the same because the lead will be part of a different 
molecule and this molecule will react to the environment differently 
than the original lead compound.
    Another commenter contended that EPA should have used the 
Multimedia Equilibrium Criterion (EQC) model to

[[Page 4524]]

estimate overall environmental persistence and partitioning of lead. 
The commenter stated that in the PBT chemical rulemaking, the Agency 
discussed how it used this model to evaluate the overall environmental 
persistence of toxic chemicals subject to the proposal (64 FR 702-703). 
The commenter believes that the EQC model is ideally suited to model 
the environmental partitioning and persistence of lead.
    The commenter is correct in stating that EPA used the EQC model to 
evaluate persistence and partitioning of toxic chemicals described in 
the PBT chemical rulemaking. EPA did not use the EQC model for metals 
in the PBT chemical rulemaking. EPA agrees that the EQC model is a 
valuable tool for determining the multimedia fate and transport of 
chemicals in the environment. As described in the PBT chemical 
rulemaking, however, the EQC model was only used to model environmental 
persistence and partitioning of organic chemicals, and not of metals. 
In the PBT chemical rulemaking, EPA based its determination of whether 
a toxic chemical is persistent based on half-lifes for specific media. 
For organic chemicals EPA used the EQC model to determine if it were 
possible that a toxic chemical that is persistent in one medium 
significantly partitions to another medium in which the toxic chemical 
rapidly degrades thus providing an overall environmental half-life less 
than the established criteria. The commenter is also correct in stating 
that the Agency did not use the EQC model to evaluate the environmental 
persistence and partitioning of lead and lead compounds. As EPA 
explained in both the PBT chemical rulemaking and the proposed lead 
rule, metals are persistent because the metal cannot be destroyed. 
While the EQC model can be used to model the partitioning of a metal 
and its compounds from one medium to another medium in the environment, 
it does not model the destruction of the metal because that cannot 
occur.
    The Agency would like to point out, however, that Mackay et al. 
(Ref. 44) used lead as an example of a ``class 2'' (nonvolatile) 
substance for an EQC model run. Because lead is classified as a ``class 
2'' chemical, the EQC model treats volatilization of lead from water to 
air and from soil to air as negligible. Mackay used an infinitely long 
degradation half-life for lead (i.e., lead is persistent and is not 
destroyed). When an infinitely long degradation half life is used (as 
was used by Mackay, et al. for lead in all media) only non-destructive 
removal processes such as loss from the air compartment by deposition 
of airborne particles to soil and water, soil runoff, advection in 
sediment (loss from the model environment by burial of sediment-bound 
lead), and transport of sediment bound lead particles out of the model 
environment are important. The overall environmental persistence of 
lead estimated by the model reflects the time necessary for lead to be 
physically transported from the model environment, not destroyed. Thus 
the model, in essence, provides information on the partitioning and 
movement of lead, but inevitably indicates that lead will be persistent 
in all media.
    The EQC level III modeling results for lead showed the importance 
of deposition from the air compartment to soil and water, at a rate 
that exceeds the advection rate (rate of non-destructive transport out 
of the model environment). The main removal mechanism according to the 
model was advection (burial) in sediment, followed by soil runoff and 
advection in water. The buildup of the chemical in the model 
environment was about 1.7  x  10<SUP>10</SUP> kg and its overall 
persistence was 5.6  x  10<SUP>6</SUP> hours (634 years), which is 
essentially infinite duration. In addition, at steady state the model 
predicted that lead concentration in the water compartment of the model 
environment would be 4.27 ug/L. For lead the important transport 
parameters are those controlling atmospheric deposition and sediment-
water exchange. EPA believes that, considering the results above and 
the discussion of the availability of lead in water, soil and sediments 
provided elsewhere in these responses to comments, the use of the EQC 
model would not have provided any information counter to EPA's position 
that lead and lead compounds are PBT chemicals. Thus, even if EPA had 
used the EQC model to estimate the environmental persistence and fate 
of lead, EPA would have drawn the same conclusions stated in the 
proposed rule. In addition, the Agency would like to emphasize that as 
discussed in the PBT chemical rulemaking the EQC model was only used as 
a secondary means to evaluate persistence and partitioning of organic 
chemical substances, and that unless all of the data inputs to the 
model were reliable it would not be used by the Agency to override 
persistence data from individual media.
    2.What comments did EPA receive on the bioaccumulation data for 
lead and lead compounds? Some commenters contend that EPA failed to 
consider the results of more recent studies that indicate that the 
accumulation of lead in aquatic organisms is low and that the 
concentrations of lead found in the environment are lower than 
previously measured. Commenters also questioned the relevance of 
laboratory bioaccumulation studies on lead to the bioaccumulation of 
lead under environmental conditions claiming that under ``realistic 
conditions'' lead does not bioaccumulate significantly in organisms. As 
discussed in detail in this section, none of these issues change EPA's 
conclusions about the validity of the data. With regard to the results 
of more recent studies, these studies do not provide information that 
changes EPA's conclusions that lead and lead compounds are 
bioaccumulative. EPA also believes that the laboratory bioaccumulation 
studies for lead are relevant to the potential for lead to 
bioaccumulate, which is confirmed by the observed bioaccumulation of 
lead in the environment.
    As discussed in Unit VI.B. of this preamble, bioaccumulation is a 
general term that is used to describe the process by which organisms 
may accumulate chemical substances in their bodies. The propensity of a 
substance to bioaccumulate in a species depends largely upon the 
pharmacokinetics of the substance in that species. That is, the extent 
to which a substance can bioaccumulate in an organism depends upon: (1) 
Whether the organism can absorb the substance; (2) the extent to which 
the substance is distributed and metabolized within the organism; and 
(3) how readily the organism can excrete the substance. The 
pharmacokinetics of a substance, and therefore the propensity for it to 
bioaccumulate, can (and often does) vary greatly among different 
species, even among species within the same trophic level. This is 
because species differ in their anatomy, physiology, and genetic 
makeup. These are important variables that govern the propensity for a 
substance to bioaccumulate, in addition to the substance's 
physicochemical and other properties. It is well established that a 
given substance can have different BAF (or BCF) values in different 
species. Data presented in Table 1 of the proposed rule (64 FR 42230) 
indicates that lead has different BAF (or BCF) values in different 
species.
    In the proposed lead rule EPA preliminarily concluded that lead and 
lead compounds are highly bioaccumulative based upon the Agency's 
review of the bioaccumulation data for lead and lead compounds in 
aquatic species and in humans. Those who commented on EPA's assessment 
of the bioaccumulative properties of lead

[[Page 4525]]

and lead compounds commented on the aquatic data used by EPA and did 
not comment on or refute the extensive data in humans. A number of 
commenters disagreed with the scientific basis that EPA used to support 
the use of bioaccumulation measurements for lead and lead compounds 
because they believe EPA's scientific basis: does not use relevant 
data; is insufficient; does not have a sound scientific foundation; or 
does not present a balanced view of the scientific literature. Other 
commenters address the issue of bioaccumulation generically, rather 
than specifically to lead and lead compounds. EPA responded to the 
generic issues in the earlier PBT chemical rulemaking (64 FR 58676) and 
in the associated Response to Comments document (Ref. 15). However, EPA 
is discussing some general issues here as background for the more 
specific issues related to lead and lead compounds in order to 
facilitate EPA's responses. Further, while some commenters agree that 
lead and lead compounds bioaccumulate, they contend that they are not 
highly bioaccumulative. A discussion of both the aquatic data and the 
human data used by EPA, and the issues raised by commenters on EPA's 
use of these data are provided below. As discussed earlier, after 
having reviewed and considered all the comments, EPA is finalizing this 
rule with a finding that lead and lead compounds are bioaccumulative, 
and is deferring its original conclusion that lead is highly 
bioaccumulative.
    a. What comments did EPA receive on the aquatic bioaccumulation 
data for lead? Aquatic species have their own unique roles in 
ecosystems and are important for the subsistence of other species, 
including consumer and predator species. Thus, the propensity of lead 
to bioaccumulate in aquatic species is of concern. Among other things, 
aquatic species comprise components of the food chain that lead to 
humans. For example, green algae are primary producers in aquatic 
ecosystems in that, through photosynthesis, they produce oxygen and 
synthesize carbohydrates and other foodstuffs (Ref. 45). These 
substances are used by consumer species which in turn serve as the food 
source for predator species, including fish. Fish in turn, serve as a 
food source for wild mammals, birds, and man. The survival of a number 
of terrestrial species, including humans, is at least partially 
dependent upon aquatic organisms. The Agency for the purposes of EPCRA 
section 313 believes all aquatic organisms to be equally relevant when 
evaluating properties of chemicals to aquatic life forms: i.e., an alga 
is viewed just as important as an oyster or a fish.
    EPA's scientific assessment of lead and lead compounds is based 
upon relevant data and has a sound scientific foundation. EPA believes 
that the scientific basis that the Agency used to support its 
conclusion that lead and lead compounds bioaccumulate in aquatic 
species is more than sufficient, and presents a balanced view of the 
scientific literature. The effects of lead and lead compounds on 
aquatic and terrestrial organisms has been studied extensively since 
the mid-1920s. A particularly active period for lead research was 
during the 1970s and 1980s, when dozens of studies were completed. In 
fact lead was one of the first chemicals extensively tested and 
monitored in water pollution and water quality studies. Thus, there are 
a plethora of studies available that investigated the environmental 
fate, availability, bioconcentration and bioaccumulation of lead and 
lead compounds. The Agency believes that these studies are relevant to 
an assessment of lead as a PBT substance, and many of these were 
reviewed by the Agency for the proposed rule. Each study reviewed by 
EPA in the development of this rule involving bioconcentration or 
bioaccumulation testing, was initially assessed by the Agency for 
quality. Not unexpectedly, the studies were found to vary in quality 
and test results to the subject organisms. Studies that were found to 
be most consistent with OPPT test guidelines were deemed valid and 
selected for use in the assessment. These studies covered a variety of 
different test species.
    The results of EPA's assessment of the bioaccumulation of lead and 
lead compounds in aquatic organisms are summarized in Table 1 of the 
proposed rule and in references therein (64 FR 42230). As can be seen 
from Table 1, the BCF values from these studies range from 390 to over 
12,000, additional information on BCF values for lead and lead 
compounds are contained in EPA's support document (Ref. 6). For a 
number of aquatic organisms that include: freshwater invertebrates such 
as mollusks, insects, and daphnid crustaceans; freshwater algae and 
phytoplankton; marine mollusks, a crustacean, and algae, lead and lead 
compounds bioconcentrate to levels above the baseline BCF criterion of 
1,000 and, for some organisms, at or above 5,000. These values are 
viewed by the Agency as indicators of the potential for increased 
exposure due to significant bioaccumulation that could occur in other 
organisms in the environment that have not been tested. Based on these 
data EPA concludes that lead and lead compounds are bioaccumulative, 
and believes that these data tend to support a finding of highly 
bioaccumulative.
    Where a range of lead BCF values was available for a specific 
organism, EPA evaluated the scientific validity of the studies 
reporting BCF values and relied upon those studies that were valid and 
scientifically sound. If valid BCF values meeting, or surpassing, the 
bioaccumulation criterion used by EPA in this rulemaking (i.e., BCF or 
BAF values greater than 1000) were identified for a species, EPA relied 
on these values as evidence that lead meets the EPCRA section 313 
bioaccumulation criterion. Although some species may have a range of 
reported BCF values, in some cases crossing the bioaccumulation 
criterion, a study reporting a lower value does not invalidate 
scientifically sound studies reporting higher values.
    The results of the majority of the studies that investigated the 
bioaccumulation of lead and lead compounds are in general agreement. 
Thus, although EPA did not review every published lead study as part of 
its assessment for the proposed rule, the scientific data EPA used to 
support its assessment of lead and lead compounds were valid, 
represented the majority of all available data on lead, and provided a 
representative sample of the available knowledge on lead.
    One commenter notes EPA's definitions of BAF and BCF on page 42229 
of the proposed lead rule. EPA defines BAF as ``the ratio of a 
substance's concentration in tissue of an aquatic organism to its 
concentration in the ambient water, in situations where both the 
organism and its food are exposed and the ratio does not change 
substantially over time.'' EPA defines BCF as ``the ratio of a 
substance's concentration in tissue of an aquatic organism to its 
concentration in the ambient water, in situations where the organism is 
exposed through water only and the ratio does not change substantially 
over time.'' The commenter questions the portions of EPA's definitions 
of BCFs and BAFs that state that the ratios do not change substantially 
over time (64 FR 42229). Specifically, the commenter claims that ``such 
ratios have little scientific relevance in themselves.'' The commenter 
states that available data indicate that the lead BCF may not be a 
constant for different exposures, species or trophic levels.
    EPA agrees with the commenter's statement that a BCF may not be

[[Page 4526]]

constant for different species or trophic levels. The Agency also 
agrees with the commenter's statement that the BAF and BCF of a 
substance measured in the same species can vary with the level of 
exposure (the concentration of the substance in ambient water). The 
Agency, however, believes the commenter has misunderstood the portions 
of its definitions of BCFs and BAFs that state that the ``ratios do not 
change substantially over time'' (64 FR 42229). The definitions of 
these terms pertain to determinations of BAF and BCF under controlled 
experimental conditions or field studies, where exposure of the aquatic 
species to the chemical is kept relatively constant. The phrase 
``ratios do not change substantially over time'' does not refer to 
different experiments conducted at different concentrations of the test 
chemical. Thus, the fact that lead BCF values may not be constant for 
different exposures, species or trophic levels does not mean that lead 
does not bioaccumulate.
    A number of commenters claim that EPA disregarded scientific data 
or did not use current scientific evidence in its assessment of the 
aquatic bioaccumulation potential of lead and lead compounds. Most of 
these commenters point out that EPA based its assessment of lead and 
lead compounds on studies published no later than the 1980s. These 
commenters are concerned that the studies EPA used are ``out-of-date''; 
flawed; were not conducted using modern day analytical techniques; and 
assert that the data provided in these studies should not have been 
used by EPA in its assessment. These commenters also claim that 
environmental studies pertaining to lead and lead compounds published 
in the 1990s indicate that lead and lead compounds are not persistent 
or bioaccumulative in aquatic species.
    While some commenters criticize the Agency for basing its 
assessment on the studies referenced in the Federal Register notice and 
in the technical support document entitled Bioaccumulation/
Bioconcentration Assessment for Lead and Lead Compounds (Ref. 6), none 
of these commenters provide persuasive criticism of the studies used by 
EPA, or of a particular data point from a study used by EPA. In many 
cases it is not clear from their comments specifically which studies 
and data these commenters feel are untrustworthy. It is difficult, 
therefore, for EPA to provide specific responses to these commenters. 
In addition, although many of the commenters claim that EPA did not use 
current scientific evidence, very few of the commenters provide 
citations to specific studies that contain more current or more recent 
scientific data. The Agency recognizes that it did not use results from 
studies published during the 1990's in its assessment of lead and lead 
compounds. EPA disagrees with the commenters, however, that the studies 
used in its analysis are ``out-of-date'', or that the data are not 
sufficiently current such that they should not have been used in the 
assessment. As with all studies used by EPA, the studies EPA used in 
its assessment of lead and lead compounds were initially reviewed by 
EPA for scientific credibility, and found to be scientifically valid. 
Many of the current methods used for biological analyses and conducting 
ecotoxicity tests are essentially the same as those used in the studies 
cited by EPA in the proposed rule. In addition, on a more general 
level, the Agency does not believe that the quality of a study should 
be judged by the year it was published, or that the results of a more 
recently published study necessarily has greater scientific validity 
than a similar study published earlier. The Agency maintains its 
longstanding position that when conducting a scientific assessment it 
is scientifically unacceptable to discriminate between study results by 
the age of the study: the selection of studies for any scientific 
assessment must be based on scientific merit.
    While the Agency did not rely on the specific results from the 
additional studies referenced and discussed by one commenter to assess 
the bioaccumulation of lead and lead compounds in developing the 
proposed rule, the studies published in the 1990s which were referenced 
by the commenters provide no significant additional information beyond 
the studies used by EPA in the proposed rule, nor do the results from 
these studies lead EPA to reconsider the characterization of lead and 
lead compounds as bioaccumulative.
    One commenter claims that more recent aquatic bioaccumulation 
studies indicate that previously reported concentrations of metals in 
environmental waters are erroneously high due to sample contamination 
(i.e., that earlier studies on the concentration of lead in the 
environment over estimated the actual concentrations of lead in the 
environment). The commenter believes that this means that previously 
reported BAF and BCF values would appear lower than if the 
concentrations of lead had not been overestimated. The commenter states 
that because of the earlier ``erroneous Pb measurements in water'', 
researchers used higher lead levels in their bioaccumulation studies 
than they otherwise would have used. The commenter states that no 
experiments have been conducted at levels close to the actual lead 
concentrations in ``natural waters.'' The commenter also stated that no 
data exists on actual lead concentrations for waters associated with 
highly contaminated sites where the results of the experiments 
conducted at concentrations above natural waters might apply. The 
commenter states that recent studies use lead concentrations 3 to 6 
orders of magnitude above actual background lead concentrations and 
that although the data cited by EPA are from studies much closer to 
levels in natural waters they are still 2 to 4 orders of magnitude 
greater than typical values of lead in natural waters. According to the 
commenter this caused higher levels of lead to occur in the organism 
than would be observed under ``actual concentrations of Pb in natural 
waters.'' The commenter tries to invalidate the concerns for 
bioaccumulation by claiming that, even though the BAFs/BCFs used by EPA 
are high, the absolute amount of lead that would bioaccumulate in 
organisms is low and does not pose a risk.
    EPA disagrees with the commenter's argument that only BAF or BCF 
values measured at ``actual concentrations of Pb in natural waters'' 
are relevant to the bioaccumulation potential of lead and lead 
compounds. At its foundation the commenter's argument is flawed because 
under EPCRA section 313 the Agency is collecting data on releases of 
lead and lead compounds to the environment which are expected to raise 
lead concentrations above natural background levels. BCF studies that 
used lead concentrations above natural background levels are valid 
since they demonstrate that lead can bioaccumulate at lead 
concentrations that may result from industrial releases. Thus the fact 
that the experiments on bioaccumulation were conducted at lead levels 
in excess of those found in ``natural waters'' does not, in itself, 
invalidate the results of those studies. As noted in Unit VI.C.3., 
testing guidelines for bioaccumulation do not state that chemicals 
should be tested at natural background concentrations, only that the 
concentrations should be below a level that is detrimental to the test 
organism. Therefore, even if better data had been available on the 
background concentrations of lead that does not mean that 
bioaccumulation studies would have been conducted at those

[[Page 4527]]

concentrations. In addition, the commenter admits that higher 
bioaccumulation values would have been reported in earlier studies if 
better data on the concentration of lead in the water had been 
available. EPA fails to see how even higher bioaccumulation values 
undermine EPA's determination that lead and lead compounds are 
bioaccumulative. EPCRA section 313 is not a risk-based program, and the 
Agency is not required to demonstrate a specific risk in order to 
classify a substance as a PBT chemical. The EPCRA section 313 
bioaccumulation criteria does not include a requirement that a chemical 
must bioaccumulate to some specific absolute amount within an organism 
in order to meet the criteria. Therefore, EPA disagrees that lead has 
not been shown to bioaccumulate to a level sufficient for inclusion as 
a PBT chemical. Even if such evidence were needed, it is available. 
EPA's database of Fish and Wildlife Advisories (http://fish.rti.org) 
contains 26 advisories for various fish and shellfish, see Unit VI.D.3. 
This indicates that lead and lead compounds can and do bioaccumulate in 
aquatic organisms to absolute levels that are of concern for human 
consumption.
    Furthermore, the commenter's contention that previously reported 
lead concentrations in ambient waters may be erroneously high only 
serves to support the conclusion that lead and lead compounds are at 
least bioaccumulative. The commenter agrees that if the previously 
reported lead concentrations in ambient waters are in fact erroneously 
high, then the previously reported BAF and BCF values for lead and 
other metals are erroneously low (because the BAF and BCF values are 
determined by dividing tissue lead concentrations by environmental 
water concentrations). Thus, if the commenter's claim about the water 
concentrations is true, then the propensity for lead and lead compounds 
to bioaccumulate in aquatic species is actually greater than originally 
estimated. Based on the commenter's concern for the validity of the 
water concentrations and the BAF and BCF values reported for lead and 
lead compounds, EPA re-reviewed the studies it used in its original 
assessment of lead and lead compounds. EPA is satisfied that the lead 
water concentrations, BCF values, and BAF values reported in these 
studies are valid. However, as noted above, EPA is deferring on a final 
conclusion regarding the classification of lead as highly 
bioaccumulative based on the data in these studies, and is concluding 
in this rule that lead is bioaccumulative.
    Two commenters contend that the extent to which a metal such as 
lead bioaccumulates is dependent upon its concentration in the aqueous 
habitat of the organism. The commenters state that in most cases where 
bioaccumulation was noted, the organisms were exposed to artificially 
elevated lead concentrations in laboratory settings, often where 
abiotic factors were manipulated to increase lead availability.
    The Agency agrees that environmental transformations and the uptake 
of lead by biota are highly variable and complex. However, these 
variabilities and complexities can be minimized by testing in the 
laboratory using a valid method. As discussed in the proposed rule, 
valid laboratory BCF tests have shown that lead and lead compounds have 
BCF values in some species well over 1,000. In some of the lead assays, 
several of the tested species (e.g., mollusks, algae) have very high 
BAF or BCF values, i.e., 5,000 or greater, indicating that these 
organisms accumulate or concentrate lead to high levels and eliminate 
lead very slowly. Thus, in organisms such as these, it would seem 
logical that the BAF or BCF values obtained at different test chemical 
concentrations would probably not vary by much. Further, based on its 
assessment of lead and lead compounds the Agency has concluded that 
external concentration is only one of several factors that govern the 
propensity for these substances to bioaccumulate in a given species. As 
discussed in more detail Unit VI.C.3, pharmacokinetic factors are 
operative as well.
    EPA does not believe that bioaccumulation of lead was documented 
mostly in cases where the concentrations of lead in the surrounding 
water were artificially elevated in laboratory settings. This was not 
the case, for example, in the freshwater and marine algal field studies 
where BAF or BCF values above 10,000 were documented in actual aquatic 
environments and the lead levels were not artificially controlled. In 
addition, the fish advisories discussed in Unit VI.D.3. were based on 
concerns for lead levels in fish and other species that did not occur 
as a result of artificially elevated lead concentrations in laboratory 
settings.
    One commenter states that EPA's contention that relatively small 
releases of lead and lead compounds have the potential to bioaccumulate 
and cause significant adverse environmental impacts is not supported by 
the scientific literature. Another commenter stated that the 
preponderance of evidence shows that only under very limited conditions 
will lead and lead compounds be available to bioaccumulate and cause 
toxic impacts to ecosystems.
    EPA disagrees. As discussed elsewhere in this document, there are 
many studies that show that there are several environmental factors 
(e.g., pH range of 3 to 6; soils that have low cation exchange 
capacity; low soil organic matter content) that increase the 
availability of lead and that, either individually or in combination, 
commonly exist throughout many geographical locations within the United 
States. However, even if the conditions under which lead is available 
were very limited this would not mean that lead would not 
bioaccumulate. Also, because lead and lead compounds are EPCRA section 
313 listed toxic chemicals that EPA has determined are persistent and 
bioaccumulative, even small releases of lead and lead compounds into 
the environment persist and have the potential to bioaccumulate and 
cause significant adverse environmental impacts. Further, EPA notes the 
data on the bioaccumulation of lead and lead compounds in human (see 
Unit VI.D.2.b.) and the fish advisories for lead (see Unit VI.D.3.).
    b. What comments did EPA receive on the human bioaccumulation data 
for lead and lead compounds? In Unit V.C. (pages 42230-42231) of the 
proposed rule, EPA provides a brief summary of available data on the 
pharmacokinetics of lead in humans. As stated in the proposed rule, EPA 
concluded that there is a substantial amount of evidence that shows 
that humans bioaccumulate lead. Unlike the assessment as to whether 
lead bioaccumulates in aquatic species, which was based on lead 
bioaccumulation factor (BAF) and bioconcentration factor (BCF) values 
measured in aquatic species in laboratory or field studies, the 
assessment of whether lead bioaccumulates in humans cannot be based on 
an analysis of BAF or BCF values because such values are not available 
for humans. The assessment of whether lead bioaccumulates in humans was 
based on the Agency's review of the references cited in Unit V.C. of 
the proposed rule, which provide a substantial amount of data and 
information regarding exposure of humans to lead, and the 
pharmacokinetics of lead in humans. From its review of these 
references, EPA concluded that humans, particularly

[[Page 4528]]

children, bioaccumulate lead to a significant degree. The propensity of 
lead to bioaccumulate in humans is known to result in toxicity to 
humans, especially infants and children. While the EPCRA section 313 
PBT chemical criteria does not require that toxicity must occur in the 
same species in which the substance bioaccumulates, or result from 
bioaccumulation of the substance, those chemicals that persist in the 
environment, bioaccumulate in humans, and are toxic to humans are 
particularly problematic in regard to human health. The following 
information on the accumulation of lead in humans is discussed in the 
references cited in the proposed rule (Refs. 8, 10, 11, 14, and 25).
    Exposure of the general population to lead occurs primarily via the 
oral and inhalation routes, and data show that in humans lead is 
absorbed from the gastrointestinal tract and the lung. Absorption of 
lead from the gastrointestinal tract varies with age. Adults absorb 
approximately 10% of orally ingested lead, and usually retain less than 
5% of what is absorbed. Children absorb up to 40% of ingested lead, and 
retain more than 5% of the absorbed quantity. Infants retain over 30% 
of the quantity absorbed following oral exposure. Research indicates 
that the differences in the extent to which lead is absorbed orally 
between adults and infants and children may be due to the increased 
need for calcium in infants and children. In infants, children, and 
adults, a transport mechanism is involved with the absorption of 
calcium from the gastrointestinal tract. Infants and children, because 
they are growing rapidly, utilize calcium for bone formation and 
growth. Dietary needs for calcium are therefore higher in infants and 
children than in adults and, consequently, calcium is more efficiently 
absorbed orally by infants and children than it is by adults. Evidence 
indicates that lead may be competing with calcium for the transport 
mechanism involved with absorption of calcium, which could explain why 
lead is absorbed from the gastrointestinal tract more efficiently in 
infants and children than it is in adults.
    Following inhalation exposure, lead is well absorbed from the lung 
by all human subpopulations. About 90% of lead particles in ambient air 
that are deposited in the lung are small enough to be retained within 
the lung. Lead retained within the lung is essentially completely 
absorbed from the lung.
    In humans, lead is known to bioaccumulate in bone. Following 
absorption, lead is distributed initially to the blood and soft tissues 
(especially the kidney, liver and bone marrow). The biological half-
life of lead in blood is generally from 1 to 2 months. Some of the lead 
in the blood is excreted, predominately in the urine. The extent and 
rate of excretion is limited, however. Eventually, lead that is not 
excreted is redistributed from the blood to teeth and bone. Once in 
bone, the biological half-life of lead can extend beyond 20 years. 
Following daily exposure to lead, a steady state blood level of lead is 
achieved after about six months. (A steady state in blood lead is 
reached when the daily intake of lead approximates the amounts excreted 
in the urine and partitioned to bone.) Once steady state is reached, 
the blood level of lead remains essentially constant. However, because 
the rate and extent of urinary excretion of lead is limited, the 
concentration of lead in bone tends to continue to increase even though 
daily exposure remains constant. Also, if the amount of daily intake 
should increase, the time to accumulate higher levels of lead in the 
blood and soft tissues shortens disproportionately since renal 
excretion and deposition into bone occurs too slowly to prevent an 
accumulation in the blood and soft tissue.
    The fraction of lead in bone increases with age from about 70% of 
total body lead in childhood to as high as 95% of the total body lead 
during old age. While lead bioaccumulates in bone, lead in bone can 
remobilize back to the blood. The extent to which lead in bone 
remobilizes to blood and other tissues is related to conditions that 
involve calcium resorption from bone. Any conditions that cause calcium 
to be resorbed from bone into the systemic circulation or other soft 
tissue will cause lead to resorb from bone. These conditions include: 
advanced age; osteoporosis; pregnancy; and lactation. Hence, lead 
stored in bone from exposures that occurred years, even decades, 
earlier may serve as an internal source of lead exposure later in life. 
lead previously accumulated in bone may contribute as much as 50% of 
blood lead.
    Lead in maternal blood can enter the fetus. Lead in fetal tissue is 
proportional to maternal blood concentration. Inorganic lead (i.e., 
Pb<SUP>0</SUP>, Pb<SUP>+2</SUP>, Pb<SUP>+4</SUP>) does not readily 
cross the blood brain barrier, and therefore only a small amount of 
inorganic lead accumulates in the brains of adult humans. Once in the 
central nervous system, however, lead accumulates in gray matter. The 
highest concentrations are in the hippocampus, followed by the 
cerebellum, cerebral cortex, and medulla. Fetuses, infants and children 
less than 4 years of age are more predisposed to accumulate inorganic 
lead in the brain than are adults because in these subpopulations the 
blood brain barrier is not completely formed. In addition to the 
ability of infants and children to absorb lead more efficiently from 
the gastrointestinal tract than adults, it is well established that 
infants and children are also more sensitive and susceptible than are 
adults to the neurotoxic effects caused by lead. Mobilization of lead 
from bone into the blood is of particular concern during pregnancy or 
lactation.
    Based on EPA's findings that in humans lead bioaccumulates in bone, 
that the concentration of lead in bone tends to continue to increase 
over the course of a lifetime, and that lead stored in bone from 
exposures that occurred previously may serve as an internal source of 
lead exposure later in life, EPA has concluded that lead significantly 
bioaccumulates in humans. In the proposed rule EPA asked for public 
comment on the scientific information concerning the bioaccumulation of 
lead in humans, and how this information should be considered in 
classifying lead and lead compounds as highly bioaccumulative. Several 
organizations or individuals provided comments to EPA's request, 
however none of these comments addressed the scientific information 
presented by EPA concerning the bioaccumulation of lead in humans, or 
how this information should be considered in classifying lead and lead 
compounds as bioaccumulative much less as highly bioaccumulative. While 
EPA believes that it could have reached a determination of 
bioaccumulative based on the human data alone, EPA concludes that lead 
and lead compounds are clearly and properly categorized as 
bioaccumulative based on the aquatic and human data. EPA further 
believes that these data would tend to support a finding of highly 
bioaccumulative.
    c. What other general comments did EPA receive on the 
bioaccumulation of lead? One commenter claimed that EPA's reasoning 
that lead bioaccumulates is based on many variables, and is not 
realistic. This commenter refers to EPA's frequent use of the words 
``may'' or ``can'' throughout the proposal: ``EPA believes that 
processes * * * can result in the release of bioavailable (ionic) lead 
where it can be bioaccumulated by organisms. These processes may occur 
in soil and aquatic environments with low pH and low levels of clay and 
organic matter.''

[[Page 4529]]

    The Agency disagrees with this commenter. As described above, EPA's 
characterization of lead as a highly bioaccumulative substance is based 
on the Agency's scientific assessment. Also, EPA's use of words such as 
``may'' or ``can'' is justifiable. EPA's TRI program is a national 
program and is not limited to specific locations or regions of the 
country. As discussed in detail in the proposed rule and elsewhere in 
this document, environmental conditions have a direct influence on the 
availability of lead and, hence, an indirect influence on the 
bioavailability and bioaccumulation of lead in aquatic organisms. 
Environmental conditions vary substantially across the United States 
and hence the availability of lead in the environment is likely to vary 
accordingly. To encompass the fact that environmental conditions vary, 
and that this rulemaking decision will be implemented at the national 
level, EPA believes its use of words such as ``can'' or ``may'' in the 
proposed lead rule is an accurate characterization of the scientific 
data. Despite the variations in environmental conditions EPA has 
concluded that there are many conditions in the United States where 
lead is available to bioaccumulate. In addition, lead is bioavailable 
even under environmental conditions where the lead ion may not be 
readily available in the environment.
    Further, there are sufficient experimental data in aquatic 
organisms, fish advisories, and extensive data in humans, all of which 
indicate that lead and lead compounds do bioaccumulate. Thus, EPA 
disagrees with the comment that the Agency's conclusion that lead 
bioaccumulates is unrealistic. To the contrary, EPA has concluded that 
the available evidence indicates that lead and lead compounds will 
bioaccumulate in many actual environments.
    Several commenters state that there are numerous literature 
citations that show that lead does not biomagnify in aquatic food 
chains, and, in experimental trophic chains lead accumulated in 
decreasing concentration from the lowest to the highest trophic levels. 
One commenter concludes that bioaccumulation is not relevant unless 
lead is transferred up the food chain to humans, and that a concept 
more meaningful than BCF is needed to evaluate the potential risk from 
lead to public health from ingestion of fish.
    EPA disagrees with the commenter's conclusion that bioaccumulation 
is not relevant unless lead is transferred up the food chain to humans 
and that BCFs [and BAFs] are not meaningful. ``Transfer up the food 
chain'' is really a biomagnification concern which EPA addressed in the 
final PBT chemical rule (64 FR 58682) and associated Response to 
Comment document (Ref. 15, section 2.d), stating that such a process is 
not relevant to the issue of whether a chemical bioaccumulates. 
Bioaccumulation is a concern for the organism that bioaccumulates it 
and any organism that eats such organisms. While available data may 
indicate that lead does not biomagnify, this has no bearing on the 
characterization of lead as a bioaccumulative substance because 
biomagnification is not required in order to have a concern for a 
chemical that bioaccumulates. While EPA does not have to make such a 
connection, the commenters' own information provides evidence of a 
transfer up the food chain. The commenter stated that about 60% of the 
lead in phytoplankton is assimilated by mussels and that mussels have 
high BCF values. EPA identified phytoplankton as having high 
bioaccumulation values so there is the potential for movement of lead 
in the food chain based on this information. In addition, EPA's 
database of Fish and Wildlife Advisories (http://fish.rti.org) contains 
26 advisories for various aquatic organisms including shellfish.
    3. What comments did EPA receive on the bioavailability of lead. 
Contrary to some commenters' claims that EPA did not consider relevant 
data regarding bioavailability, EPA emphasizes that the Agency did 
consider the bioavailability of lead in its evaluation of lead and lead 
compounds. In addition to the principles described above in Unit 
VI.C.2. that address the availability and bioavailability of metals, 
EPA also relied on empirical data regarding the availability and 
bioavailability of lead. EPA refers specifically to the test data cited 
in the proposed rule and in the references to the proposed rule that 
clearly show that lead is bioavailable (Table 1 of the proposed rule 
(64 FR 42230), and references therein). The fact that lead is 
detectable in the tissues of snails, algae, plankton, rainbow trouts, 
blue mussels, oysters, and lobsters exposed to lead provides compelling 
scientific evidence that lead is bioavailable in these species.
    In addition to these test data, EPA examined its public National 
Listing of Fish and Wildlife Advisories database (see http://fish.rti.org/) to see whether lead has been detected in fish under 
actual environmental conditions. The individual states have the primary 
responsibility for protecting residents from the health risks of 
consuming contaminated noncommercially caught fish and wildlife. 
Individual counties monitor local fish and wildlife for the presence of 
chemical contaminants, including lead. Fish consumption advisories warn 
the public that high concentrations of chemical contaminants have been 
found or are suspected in fish from local waters and that consumption 
of these fish may pose health risks. The advisories may recommend to 
limit or avoid consumption of specific fish species, or to limit or 
avoid consumption of fish from specific water bodies. It is important 
to emphasize that while a single advisory has one geographic location 
(e.g., a portion of a river or lake), it can contain information about 
several fish species (e.g., carp, largemouth bass, shrimp), several 
pollutants (e.g., mercury and PCBs), and several ``populations'' (e.g., 
no consumption for at risk subpopulations such as pregnant women and/or 
restricted consumption for general populations). There are 26 reports 
that show that lead is or has been detected in different aquatic 
species located in various areas within the United States. The fact 
that lead is detected in fish shows that lead is bioavailable in fish 
under actual and varying environmental conditions. Being within the 
purview of state and local governments, there is some variation in fish 
advisory policies and procedures across the United States. Thus, not 
all counties monitor fish and wildlife for chemical contaminants, and 
some counties may not monitor for lead contamination. Therefore, there 
may be additional geographical locations within the United States, not 
listed in the National Listing of Fish and Wildlife Advisories 
database, where the fish are contaminated with lead.
    Some commenters state that EPA should evaluate each individual 
member of the lead compounds category on a case-by-case basis because 
the availability of lead from lead compounds differs among lead 
compounds and lead is unavailable from certain lead compounds. As 
explained in Unit VI.C.1., the Agency has concluded that there is a 
scientific basis for evaluating lead compounds as a category rather 
than individually because the bioavailability of a lead compound is not 
necessarily dependent upon the availability of lead from the compound. 
That is, the parent lead compound may be bioavailable as is or, if not 
itself bioavailable, could be converted in the environment into a 
another lead compound that is bioavailable or from which lead is 
bioavailable. As discussed in Unit VI.D.1, EPA's environmental fate 
assessment indicates that there are

[[Page 4530]]

many conditions under which lead from lead compounds can become 
available in the environment. Further, most lead compounds provide 
bioavailable lead when ingested. Thus, after an evaluation of the 
available data, EPA has determined that the weight of scientific 
evidence indicates that it is reasonable to conclude, based upon 
similarities between the compounds, that lead in the environment will 
be available and/or bioavailable from all lead compounds.
    In addition, regardless of the relative environmental availability 
of lead from one lead compound to another, the lead compounds all add 
to the environmental loading of lead. Thus, even if under the same 
environmental conditions the lead from compound A is 10 times less 
available than the lead from compound B, compound A would introduce the 
same amount of available lead if its releases are 10 times greater. If 
lead compounds are evaluated individually based on relative 
environmental availability then the additive effect of the loading of 
lead from these compounds would be ignored.

E. What Comments Did EPA Receive on Its Proposed Threshold for Lead and 
Lead Compounds?

    EPA received a range of comments on the thresholds proposed for 
lead and lead compounds similar to those it received on the thresholds 
proposed for the PBT chemicals in its earlier rulemaking. Many 
commenters contended that EPA should not consider burden in choosing 
thresholds. They believe that EPA should set a threshold of 1 pound for 
lead because it was proposed as falling within the subset of PBT 
chemicals that are both highly persistent and highly bioaccumulative. 
Numerous commenters believe that the threshold for reporting should be 
zero. Other commenters believe that burden should have been a greater 
consideration in EPA's choice of reporting thresholds. Many of these 
commenters also stated that EPA should set thresholds based on some 
percentage of releases that would be reported.
    With few exceptions, the comments EPA received failed to take into 
account the analyses EPA laid out in the final PBT chemical rule. As 
explained in the preamble to that rule, the analyses in that rulemaking 
relied on the characteristics and policy considerations surrounding PBT 
chemicals in general. The analyses were not dependant on the specific 
chemical properties of the particular, individual chemicals addressed 
in that rulemaking, but were tied more closely to the overall 
characteristics of PBT chemicals generally. For example, as part of the 
explanation for the Agency's decision to establish two categories of 
thresholds an order of magnitude apart, EPA noted:

    EPA then considered the relative degree of persistence and 
bioaccumulation between the two classes of chemicals. EPA wanted to 
establish two sets of revised thresholds with the same approximate 
relationship to each other, as the relative exposure potentials of 
PBT chemicals to that subset of highly persistent and highly 
bioaccumulative PBT chemicals. Simply stated, chemicals with half-
lifes of 6 months or greater and a BAF/BCF of 5,000 or greater have 
a higher exposure potential than chemicals with half-lifes of 2 
months or greater and a BAF/BCF of 1,000 or greater. However, 
although, as discussed below, EPA could establish a qualitative 
relationship, the Agency could not reliably quantify the relative 
exposure potential across the board for all of the members of both 
classes. Therefore, in attempting to translate the qualitative 
exposure potential of PBT chemicals to that subset of PBT chemicals 
that are highly persistent and highly bioaccumulative into a 
qualitative threshold relationship, EPA considered both the 
attributes of these chemicals and factors specific to thresholds. 64 
FR 58690.

    And as EPA also explicitly noted in the preamble, EPA established 
the revised thresholds with the intention that they would be generally 
applicable to future members of the two PBT categories. See 64 FR 
58691. Thus, absent some strong technical or policy concern to the 
contrary-a topic on which the public would have the opportunity to 
present information and otherwise provide comments--the revised 
thresholds were anticipated to be applicable to future candidate PBT 
chemicals. EPA requested commenters to submit such technical and policy 
concerns in its proposed rule for lead and lead compounds. See 64 FR 
42224. This, the commenters have failed to do. In addition, in the 
proposed lead rule, EPA identified an additional factor for use in 
determining whether a chemical is, at the least, bioaccumulative. EPA 
explained that there is clear and convincing evidence that lead is 
bioaccumulative in humans. EPA also requested comment on the human data 
and on how such data should be considered in determining whether a 
chemical should be classified in that subset of PBT chemicals that are 
highly bioaccumulative. Therefore, consistent with the factors laid out 
in its previous rulemaking, and with its determination that lead and 
lead compounds are highly persistent and bioaccumulative toxic 
chemicals, EPA is setting the thresholds for lead and lead compounds at 
100 pounds. As discussed elsewhere, following its review of the 
comments, EPA is deferring on its proposal to classify lead and lead 
compounds as highly bioaccumulative.
    Consistent with EPA's approach to revise thresholds for PBT 
chemicals, EPA began with the premise that for lead and lead compounds, 
assuming no unique circumstances, a threshold of either 100 or 10 
pounds would be warranted. The choice of threshold was dependent on 
whether the data indicated that lead and lead compounds were PBT 
chemicals, or fell within the subset of highly persistent and highly 
bioaccumulative toxic chemicals. In this rulemaking EPA has concluded, 
through application of PBT criteria as discussed in the PBT final rule 
and the proposed lead rule, that lead and lead compounds are highly 
persistent and bioaccumulative. At this time, EPA is deferring on a 
final conclusion as to whether lead and lead compounds are highly 
bioaccumulative, and is deferring on whether lead and lead compounds 
are appropriately classified in that subset of toxic chemicals that are 
highly persistent and highly bioaccumulative. Thus, based on EPA's 
conclusions, a 100 pound threshold for lead and lead compounds is 
warranted.
    EPA has considered the same factors for lead and lead compounds 
that it had considered for the individual PBT chemicals included in its 
previous rulemaking. To determine whether the additional reporting 
burden associated with lowering the thresholds for lead and lead 
compounds presented any unique concerns, and to ensure that the 100 
pound threshold would capture significant information from a range of 
covered industry sources, EPA analyzed the number of reports that would 
be submitted by each industry sector for the following potential 
thresholds: 1 pound, 10 pounds, 100 pounds, and 1,000 pounds.
    EPA's analysis confirmed that 100 pound threshold achieves the 
appropriate balance of the various factors laid out in the preamble to 
the final PBT rule. EPA therefore finds that establishing the threshold 
at 100 pounds will not be unduly burdensome, and ensures that the 
resulting reporting will provide the public with information from a 
range of covered industry sectors, and that the information will 
contribute significantly to providing the public with a comprehensive 
picture of toxic chemical releases and potential exposures to humans 
and ecosystems.

[[Page 4531]]

F. What Comments Did EPA Receive on Its Proposed Treatment of Lead 
Contained in Stainless Steel, Brass, and Bronze Alloys?

    The commenters on this issue generally agree with EPA's proposed 
limitation on the reporting of lead contained in stainless steel, 
brass, and bronze alloys, but felt that it should be expanded. Some 
commenters suggest that all alloys should be included, while others 
cited various types of alloys that they believed should also be 
included, e.g., aluminum, copper, zinc, tin, iron, all steels, carbon 
and low alloy steels, leaded steel, and galvanized and drawn steel 
wire. Some commenters also suggest that other metals be included in a 
broader alloy reporting exemption and that the exemption should be for 
all reporting, not just for the lower reporting thresholds. Some 
commenters claim that EPA's reasoning in drafting the alloys exemption 
is that lead incorporated into an alloy does not pose the same hazard 
as unincorporated lead, is not bioavailable, does not exert toxic 
effects, is not available for exposure, and that this reasoning holds 
true for lead contained in other alloys. Commenters also contend that 
alloys have significantly different bioavailability, bioaccumulation, 
and toxicity characteristics than other forms of metals, and thus 
should be treated separately. Some comments state that an alloys 
exemption would enhance the ability of TRI to provide meaningful 
information to the public regarding the risk associated with the 
release and handling of toxic materials. Several commenters requested 
an exemption for the use of lead and lead compounds in wire soldering 
operations. Some commenters state that lead contained in primary 
aluminum and aluminum alloys is incidental and that the concentrations 
are significantly lower than that found in stainless steel, bronze and 
brass alloys, which intentionally contain lead, and therefore lead in 
aluminum alloys should not be regulated any more stringently than those 
alloys. One commenter states that EPA failed to demonstrate that lead 
is bioavailable in any metal alloy and illegitimately provided a 
preferential exemption only to certain metal alloys. The commenter 
contends that EPA has failed to show any rational basis for excluding 
other metal alloys from such an exemption and that limiting the 
exemption to stainless steel, brass, and bronze alloys is arbitrary and 
capricious and should be expanded to all, metal alloys, including 
aluminum alloys.
    EPA does not believe that it currently has any information that 
would support a decision to extend to other types of alloys, its 
deferral of a decision on a lower threshold for lead when contained in 
stainless steel, brass, and bronze alloys. EPA's proposed deferral was 
based on the fact that it is currently evaluating a previously 
submitted petition, as well as comments received in response to 
previous petition denials, that requested the Agency to revise the 
EPCRA section 313 reporting requirements for certain metals contained 
in stainless steel, brass, and bronze alloys. Contrary to the 
commenter's allegations, EPA has not determined that lead is neither 
toxic nor bioavailable when contained in these or any other alloys. Nor 
did EPA imply that lead or other metals contained in these or any other 
alloys are less hazardous than metals not contained in alloys, or that 
lead or other metals cannot exert toxic effects, or that lead or other 
metals are not available for exposure when contained in an alloy. 
Rather, the deferral is simply based on the fact that for stainless 
steel, brass, and bronze alloys, EPA is currently reviewing whether 
there should be any reporting changes. In light of that review, EPA has 
decided to maintain the status quo for lead when contained in these 
alloys until the review is complete.
    Lead is an EPCRA section 313 listed toxic chemical, and lead 
contained in all alloys are therefore subject to the EPCRA section 313 
reporting requirements. As discussed above, EPA did not illegitimately 
provide a preferential exemption only to stainless steel, brass, and 
bronze alloys. EPA is merely maintaining the status quo with respect to 
the alloys that are the subject of the pending review. Other alloys are 
not part of that review. Because the commenters have submitted no 
information or data that would allow the Agency to conclude that lead 
in all other alloys are similarly situated, in light of its scientific 
findings in this rule with respect to lead and lead compounds, EPA has 
no basis for extending its deferral.
    With respect to the request for an exemption for lead soldering, 
EPA does not believe that the commenter's allegation that lead may not 
be released during these processes, such as wire soldering, provides an 
adequate basis for excluding that activity from threshold 
determinations and release reporting requirements. Under EPCRA section 
313, whether an activity must be counted towards an EPCRA section 313 
reporting threshold is based on whether the activities fall within the 
definition of manufacturing, processing, or otherwise use, not on 
whether the activity actually, or potentially, results in releases. 
Additionally, because even low amounts of releases are of concern for 
PBT chemicals like lead and lead compounds, it is not appropriate to 
exclude a reportable activity merely because releases from that 
activity may be relatively low.
    In addition, this rulemaking is specific to lead and is not the 
appropriate forum to address the issue of limitations or exemptions for 
other metals contained in these or other alloys; nor was comment on 
such issues requested in the proposed rule. EPA will be issuing a 
report on its review of the data for stainless steel, brass, and bronze 
alloys and will be asking for comments on the report.
    The comment that an alloys exemption would enhance the ability of 
TRI to provide meaningful information to the public regarding the risk 
associated with the release and handling of toxic materials is not 
relevant to the issue of whether or not there should be reporting 
changes for any alloys. As EPA has previously discussed (64 FR 58592), 
EPCRA section 313 is a hazard-based program, not a risk-based program. 
As such, EPCRA section 313 does not directly provide any risk 
information to its users, but rather provides basic release and other 
waste management information on chemicals that meet the criteria in 
EPCRA section 313(d)(2). Congress established these criteria as the 
sole standard for listing decisions. Therefore, any final determination 
on whether there should be changes to the reporting of alloys will be 
based on whether the alloys meet the criteria of EPCRA section 
313(d)(2).
    One commenter stated that EPA's limitation on the reporting of lead 
contained in alloys should apply to all alloys to be consistent with 
that proposed for cobalt and vanadium in the January 1999 proposal for 
other PBT chemicals.
    EPA disagrees that it must extend its deferral to all lead alloys 
to be consistent with its past actions on cobalt and vanadium. With 
respect to cobalt, in the October 29, 1999 final PBT chemical rule (64 
FR 58666), EPA only changed the reporting requirements for vanadium not 
cobalt. Regarding vanadium, the original vanadium listing contained the 
qualifier ``fume or dust;'' thus the status quo was that unless the 
vanadium alloy was converted to a fume or dust form, the vanadium in 
any alloy was not reportable. In the October 29, 1999 final rule, EPA 
added all forms of vanadium, except vanadium contained in alloys, to 
the list of TRI chemicals. EPA deferred its decision to add vanadium 
contained in alloys until it

[[Page 4532]]

had resolved the pending petition. EPA explained its decision as 
follows: ``At this time, while EPA is in the process of a scientific 
review of the issues pertinent to alloys, the Agency is not prepared to 
make a final determination on whether vanadium in vanadium alloys meet 
the EPCRA section 313(d)(2) toxicity criteria'' (64 FR 58711).
    At the time EPA made its determination with respect to vanadium, 
EPA chose not to add vanadium contained in any alloys to the EPCRA 
section 313 list of toxic chemicals. This decision excluded from a 
listing decision more than just the three classes of alloys 
specifically addressed in the alloys project out of concern that the 
project could be expanded to similar alloys. However, at the time of 
the lead proposal, EPA identified a potential concern with proposing a 
similarly broad deferral for lead since lead is used in many types of 
alloys that are not similar to stainless steel, brass, and bronze 
alloys. Because these other alloys, such as lead solder, are not being 
reviewed, and are currently subject to reporting under EPCRA section 
313, EPA believes that the Agency has no basis to defer lowering 
thresholds for these other alloys. In light of the Agency's conclusions 
with respect to lead, EPA will review its October 29, 1999, vanadium 
decision and determine whether vanadium contained in alloys, other than 
the three classes of alloys currently under review by the Agency, 
should be added to the EPCRA section 313 list of toxic chemicals.
    None of the commenters who supported a limitation for lead in other 
alloys submitted any data on which the Agency could rely to create such 
a limitation, or to extend the alloys review to encompass lead when 
contained in alloys other than stainless steel, brass, or bronze. As 
explained above, EPA believes that it has no basis to defer lowering 
thresholds for other alloys that are not currently being reviewed. If 
the commenter has data to support a revision to the reporting 
requirements for lead when contained in alloys other than stainless 
steel, brass, and bronze the commenter can submit it as part of a 
petition to delist lead contained in such alloys from the EPCRA section 
313 list of toxic chemicals.
    One commenter contends that EPA has exempted steel, brass and 
bronze alloys from reporting for lead with the implication being that 
these alloys do not yield sufficient lead to be a significant risk. The 
commenter stated that there are many products containing trace amounts 
of lead which are at least as stable as bronze or steel alloys. The 
commenter contends that EPA provides no explanation for why these other 
products were not also provided an exemption and that EPA sets forth an 
artificial and unfair distinction. The commenter cites colored 
plastics, vinyl siding, ceramics, paints and inks as examples of 
products that do not leach lead in sufficient quantity to pose a risk 
to the community. The commenter contends that there is an assumption 
implicit in the proposed rule, that steel alloys containing lead are 
sufficiently safe and non-toxic to avoid reporting under the TRI, while 
all other forms of lead, lead compounds and thousands of products which 
may contain trace quantities of lead and lead compounds are not and 
that this is unsubstantiated in the record for this rulemaking.
    EPA is not providing an ``exemption'' to lead contained in 
stainless steel, brass and bronze alloys. As EPA discussed in other 
responses in these section, EPA is merely deferring a final decision on 
lowering thresholds for lead contained in these alloys until the 
scientific review of the alloys petition is complete. EPA has made no 
determination, implicit or otherwise, that lead contained in any alloy 
is safe, non-toxic, or without significant risk. Lead contained in 
other non-alloy products is currently reportable and since these other 
non-alloys are not part of the review of stainless steel, brass, and 
bronze alloys EPA did not include any similar deferral for these other 
products. With regard to these other lead containing products, if the 
commenter has data that indicate that the lead contained in these 
products cannot become available through any abiotic or biotic 
processes, then they may wish to provide these data in a petition to 
have the lead in such products delisted from the EPCRA section 313 
listed toxic chemicals. In addition, under certain conditions, some of 
the products mentioned by the commenter (such as vinyl siding, colored 
plastics, and ceramics) may be eligible for the article exemption (see 
40 CFR Sec. 372.38 (b)) and thus would not be subject to reporting in 
any case.
    Two commenters requested that lead and lead compounds contained in 
glass, ceramic enamels, and ceramicware be excluded from reporting. One 
commenter stated that EPA's limitation on the reporting of lead in 
stainless steel, brass, and bronze alloys, is apparently justified 
because alloys have significantly lower potential for bioavailability, 
bioaccumulation, and toxicity than other forms of metals and are less 
likely to affect organisms than non-alloy forms of metals and that 
these compounds are extremely stable and virtually unable to interact 
with organisms. The commenter contends that ceramic enamels share 
similar properties with alloys and that the way that they are 
manufactured and used results in little or no releases or exposures. 
The commenter stated that these enamels are as insoluble as possible 
and bind the lead compounds in such a way that their use in glazing and 
decorating ceramicware or glass would strictly limit the potential 
exposure of the community to releases from a glazing or decorating 
process.
    As discussed in detail in the responses contained in the previous 
section, EPA has not determined that lead is neither toxic nor 
bioavailable when contained in these or any other alloys. Nor did EPA 
imply that lead or other metals contained in these or any other alloys 
are less hazardous than metals not contained in alloys, or that lead or 
other metals cannot exert toxic effects, or lead or other metals are 
not available for exposure. EPA is merely deferring a final decision on 
lead contained in these alloys until the Agency completes it current 
review of the alloys petition. The commenter has provided no data to 
support expanding its alloys review to these materials so the basis for 
the deferral for lead in certain alloys does not apply to these other 
materials. If the commenter has data to support such an extension, then 
they may wish to provide this data in a petition to have the lead in 
such products delisted from the EPCRA section 313 listed toxic 
chemicals. In addition, under certain conditions, glass and ceramic 
products may be eligible for the article exemption (see 40 CFR 
Sec. 372.38 (b)) and thus would not be subject to reporting in any 
case.

VII. What Are the Results of EPA's Economic Analysis?

    EPA has prepared an economic analysis of this action, which is 
contained in a document entitled Economic Analysis of the Final Rule to 
Modify Reporting of Lead and Lead Compounds Under EPCRA Section 313 
(Ref. 46). This document is available in the public version of the 
official record for this rulemaking. The analysis assesses the costs, 
benefits, and associated impacts of the rule, including potential 
effects on small entities. The major findings of the analysis are 
briefly summarized here including responses to some of the major 
comments EPA received.

A. What Is the Need for the Rule?

    Federal regulations exist, in part, to address significant market 
failures.

[[Page 4533]]

Markets fail to achieve socially efficient outcomes when differences 
exist between market values and social values. Two causes of market 
failure are externalities and information asymmetries. In the case of 
negative externalities, the actions of one economic entity impose costs 
on parties that are ``external'' to any market transaction. For 
example, a facility may release toxic chemicals without accounting for 
the consequences to other parties, such as the surrounding community, 
and the facility's decisions will fail to reflect those costs. The 
market may also fail to efficiently allocate resources in cases where 
consumers lack information. For example, where information is 
insufficient regarding toxic releases, individuals' choices regarding 
where to live and work may not be the same as if they had more complete 
information. Since firms ordinarily have little or no incentive to 
provide information on their releases and other waste management 
activities involving toxic chemicals, the market fails to allocate 
society's resources in the most efficient manner.
    This action is intended to address the market failures arising from 
private choices about lead and lead compounds that have societal costs, 
and the market failures created by the limited information available to 
the public about the release and other waste management activities 
involving lead and lead compounds. Through the collection and 
distribution of facility-specific data on toxic chemicals, TRI 
overcomes firms' lack of incentive to provide certain information, and 
thereby serves to inform the public of releases and other waste 
management of lead and lead compounds. This information enables 
individuals to make choices that enhance their overall well-being. 
Choices made by a more informed public, including consumers, corporate 
lenders, and communities, may lead firms to internalize into their 
business decisions at least some of the costs to society relating to 
their releases and other waste management activities involving lead and 
lead compounds. In addition, by helping to identify areas of concern, 
set priorities and monitor trends, TRI data can also be used to make 
more informed decisions regarding the design of more efficient 
regulations and voluntary programs, which also moves society towards an 
optimal allocation of resources.
    Certain facilities currently report TRI data on lead and lead 
compounds under the existing 10,000 and 25,000 pound reporting 
thresholds. In 1998, EPA received TRI data on the release and other 
waste management of over a billion pounds of lead and lead compounds 
from approximately 1,900 facilities. EPA believes that there are many 
additional facilities that do not currently report lead and lead 
compounds to TRI because they do not exceed current reporting 
thresholds for lead and lead compounds, and/or because the lead-
containing materials they handle are currently covered by the de 
minimis exemption. EPA is not able to estimate the total multi-media 
releases or other waste management quantities from these additional 
facilities without additional TRI reporting. Since even small amounts 
or concentrations of lead and lead compounds are of concern, EPA 
believes that there is a need for reporting from these additional 
facilities.
    If EPA were not to take this action, the market failure (and the 
associated social costs) resulting from the limited information on the 
release and disposition of lead and lead compounds would continue. EPA 
believes that today's action will improve the scope of multi-media data 
on releases and other waste management of lead and lead compounds. 
This, in turn, will provide information to the public, empower 
communities to play a meaningful role in environmental decision-making, 
and improve the quality of environmental decision-making by government 
officials. In addition, this action will serve to generate information 
that reporting facilities themselves may find useful in such areas as 
highlighting opportunities to reduce chemical use or release and 
thereby lower costs of production and/or waste management. EPA believes 
that these are sound rationales for lowering reporting thresholds for 
lead and lead compounds.

B. What are the Potential Costs of this Action?

    This action will result in the expenditure of resources that, in 
the absence of the regulation, could be used for other purposes. The 
cost of the rule is the value of these resources in their best 
alternative use. Most of the costs of the rule will result from 
requirements on industry. Approximately 9,800 facilities are expected 
to submit additional Form R reports on an annual basis as a result of 
this action. The estimated composition of this reporting, by industry, 
is shown in Table 1. This table also displays the estimated costs for 
this action, which includes costs of compliance determination for all 
potentially affected facilities, and rule familiarization, report 
completion, and mailing/recordkeeping for facilities that are expected 
to file additional reports. Aggregate industry costs in the first year 
for the selected alternative are estimated to be $80 million; in 
subsequent years they are estimated to be $40 million per year. 
Industry costs are lower after the first year because facilities will 
be familiar with the reporting requirements, and many will be able to 
satisfy reporting requirements by updating or modifying information 
from the previous year's report. EPA is expected to expend $1.2 million 
in the first year, and $775,000 in subsequent years for programmatic, 
compliance assistance, and enforcement activities as a result of the 
rule.

                         Table 1. Summary of Estimated Additional Reporting by Industry
----------------------------------------------------------------------------------------------------------------
                                                                 Estimated Industry Costs (thousand $ per year)
          SIC Code--Industry             Estimated Number of   -------------------------------------------------
                                          Additional Reports           First Yr.                 Sub. Yr.
----------------------------------------------------------------------------------------------------------------
10--Metal Mining                       127                      $756                     $459
----------------------------------------------------------------------------------------------------------------
12--Coal Mining                        314                      $1,782                   $1,163
----------------------------------------------------------------------------------------------------------------
20--Food                               291                      $2,857                   $1,380
----------------------------------------------------------------------------------------------------------------
21--Tobacco                            29                       $170                     $106
----------------------------------------------------------------------------------------------------------------
22--Textiles                           184                      $1,359                   $761
----------------------------------------------------------------------------------------------------------------

[[Page 4534]]

 
23--Apparel                            16                       $1,339                   $371
----------------------------------------------------------------------------------------------------------------
24--Lumber                             107                      $1,998                   $744
----------------------------------------------------------------------------------------------------------------
25--Furniture                          60                       $958                     $377
----------------------------------------------------------------------------------------------------------------
26--Paper                              211                      $1,938                   $894
----------------------------------------------------------------------------------------------------------------
27--Printing                           41                       $2,646                   $755
----------------------------------------------------------------------------------------------------------------
28--Chemicals                          497                      $3,327                   $1,968
----------------------------------------------------------------------------------------------------------------
29--Petroleum                          95                       $589                     $364
----------------------------------------------------------------------------------------------------------------
30--Plastics                           84                       $1,685                   $613
----------------------------------------------------------------------------------------------------------------
31--Leather                            18                       $185                     $87
----------------------------------------------------------------------------------------------------------------
32--Stone/Clay/Glass                   186                      $1,889                   $898
----------------------------------------------------------------------------------------------------------------
33--Primary Metals                     1,945                    $11,931                  $7,049
----------------------------------------------------------------------------------------------------------------
34--Fabricated Metals                  267                      $3,865                   $1,577
----------------------------------------------------------------------------------------------------------------
35--Machinery                          53                       $3,083                   $892
----------------------------------------------------------------------------------------------------------------
36--Electrical Equipment               3,501                    $25,957                  $12,737
----------------------------------------------------------------------------------------------------------------
37--Transportation Equipment           347                      $2,462                   $1,409
----------------------------------------------------------------------------------------------------------------
38--Measure./Photo.                    7                        $723                     $197
----------------------------------------------------------------------------------------------------------------
39--Miscellaneous                      58                       $1,103                   $380
----------------------------------------------------------------------------------------------------------------
4911/4931/4939--Electric Utilities     574                      $3,025                   $2,069
----------------------------------------------------------------------------------------------------------------
4953--Refuse Systems                   107                      $561                     $385
----------------------------------------------------------------------------------------------------------------
5169--Chemical Wholesale               0                        $299                     $75
----------------------------------------------------------------------------------------------------------------
5171--Bulk Petroleum                   616                      $3,539                   $2,293
----------------------------------------------------------------------------------------------------------------
7389--Solvent Recovery Services        78                       $417                     $283
----------------------------------------------------------------------------------------------------------------
Total                                  9,813                    $80,441                  $40,287
----------------------------------------------------------------------------------------------------------------

    A number of commenters contend that EPA's analysis of affected 
industry sectors for the proposed rule failed to include sectors that 
would be affected by the rule. These commenters suggest that the 
following industries would be affected by the rule: metalworkers; 
glaziers; lead crystal glassware manufacturers; animal feed producers; 
metal platers; brass and copper fabricators; stained glass 
manufacturers; organ makers and manufacturers of other musical 
instruments; dye makers and manufacturers of dye-containing products 
including businesses in the leather, garment, and textile industries; 
pigments and coatings companies; metal finishers; medical and dental 
equipment manufacturers; makers of sporting and recreational equipment; 
precision metal components, mirrors, stabilizers, fertilizer; and 
numerous ceramic decorative art manufacturers and studios; art pottery 
and art pottery supply firms; ink formulators; print shops; product 
painting/coating/refinishing businesses; and packaging or packaging 
coating firms, and other businesses that use or manufacture materials 
that contain small amounts of lead.
    In the economic analysis for the proposed rule (Ref. 16), EPA 
estimated the additional TRI reporting that would be expected from a 
number of industry groups that are subject to EPCRA section 313 at four 
lower reporting thresholds considered for lead and lead compounds. EPA 
also identified other industry groups, which are also subject to EPCRA 
section 313, but for which EPA lacked sufficient information to 
generate quantitative estimates of additional reporting. In the 
proposed rule, and in a subsequent notice announcing public meetings, 
EPA solicited additional information to allow EPA to quantify the 
number of additional reports in all industry groups that are subject to 
EPCRA section 313. In response, EPA received comments that varied 
greatly in detail and utility for making quantitative estimates of 
additional reporting.
    In some cases, in addition to asserting that an industry sector 
would be affected by the rule, commenters also provided detailed 
information on the activity in the industry sector associated with lead 
or lead compounds, the

[[Page 4535]]

amount or concentration of lead associated with industrial materials, 
the lead usage per employee, the prevalence of the lead-related 
activity within the industry, or other information that allowed EPA to 
confirm the potential for additional reporting in that industry at the 
various proposed lower reporting thresholds. This information, in 
conjunction with additional research and industry contacts, allowed EPA 
to revise or generate estimates for many of the additional industry 
sectors that commenters identified. These sectors include galvanizers, 
stained glass manufacturers, metal finishers, animal feed producers, 
organ manufacturers, and other industry sectors described in Appendix A 
of the economic analysis of the final rule (Ref. 46).
    In other cases, commenters asserted a potential impact on an 
industry without providing information that would allow EPA to confirm 
the potential for additional reporting as a result of the rule, or to 
make a quantitative estimate of additional reporting at any of the 
lower reporting threshold options that EPA considered. Table A-73 in 
the economic analysis of the final rule lists industries that may be 
affected by the rule, but for which existing data are inadequate to 
make a quantitative estimate of additional reporting.
    EPA fully considered the information from the commenters on the 
potential for additional reporting from industries that were not 
identified in the economic analysis of the proposed rule, or for which 
EPA was unable to make quantitative estimates at the time of the 
proposal. As a result of the comments, EPA revised its estimates for a 
number of potentially affected industry groups. The revised estimates 
are described in Appendix A of the economic analysis of the final rule. 
While the estimates of additional reporting for some industry groups 
changed substantially as a result of the comments, the net effect on 
EPA's estimates of additional reporting was less pronounced because 
estimates for some industry sectors increased while others decreased. 
(Additional details are available in Appendix A of the economic 
analysis of the final rule.)
    With regard to the potential for additional reporting, a number of 
commenters cite the following footnote to Table A-45 in Appendix A of 
the economic analysis of the proposed rule:
    Zero facilities are predicted to report for lead due to natural gas 
combustion given the uncertainty regarding concentration data for lead 
in natural gas. Assuming available concentration data are accurate, an 
estimated 35,376 additional facilities would report at the proposed 
threshold.
    The commenters note that this estimate for natural gas users would 
greatly increase the number of additional reports that EPA estimated 
for the proposed rule. Although one commenter notes that EPA explained 
that ``concentration data for natural gas are considered unreliable,'' 
the commenters ask that EPA explain why it chose to reject the 
available concentration data for lead in natural gas, but not the data 
it used for lead in other fuels.
    The footnote cited by the commenters reflects EPA's assessment of 
the quality of available information on the presence of lead as a trace 
contaminant in natural gas at the time of proposal. Because of 
uncertainties about the presence or absence of lead as a trace 
contaminant in natural gas, EPA did not include any reporting due 
solely to natural gas combustion in its quantitative estimates of 
additional lead and lead compound reporting at the lower reporting 
threshold options.
    For the economic analysis of the proposed rule, EPA consulted two 
references for information on lead in natural gas: Locating and 
Estimating Air Emissions from Sources of Lead and Lead Compounds (Ref. 
47) and Study of HAP Emissions from Electric Utility Steam Generating 
Units: Final Report to Congress (Ref. 48). These references provided 
emission factors for lead from natural gas combustion based on a very 
limited number of observations. The observed emissions of lead do not 
necessarily indicate that lead was present as a trace contaminant in 
natural gas. For example, the lead measured in emissions from natural 
gas combustion may have originated from lead-containing oil residues in 
combined-cycle combustion units. In this case, the effect on additional 
reporting would have been captured in EPA's estimate of reporting due 
to lead levels in residual or distillate fuel oil. Due to this 
uncertainty about the origin of lead emissions from natural gas 
combustion, EPA estimated the potential number of additional reports 
based on the lead emission factor for natural gas, but did not include 
these reports in the quantitative estimate of additional reporting at 
the lower reporting threshold options. For other fuels, EPA was able to 
locate typical concentration values for lead contained in those fuels a 
trace contaminant. Therefore, for fuels other than natural gas, EPA 
included estimates of additional reporting due to fuel combustion at 
the lower reporting threshold options.
    As a result of public comments on this issue, EPA sought additional 
information to verify if lead is found as a contaminant in natural gas. 
EPA located a report that characterizes the presence of hazardous air 
pollutants in natural gas (Ref. 49). According to this report, lead was 
not detected at a detection limit of 0.9 micrograms per cubic meter of 
natural gas. Assuming, as an illustrative example, that lead was 
present at the detection limit concentration, the facility at the 90th 
percentile of manufacturing facilities using natural gas would only 
have a lead throughput of 0.05 lbs per year based on natural gas 
throughput data presented in the economic analysis of the final rule. 
Because the currently available data reviewed by EPA on trace levels of 
lead and lead compounds in natural gas indicate that very few, if any, 
facilities would be affected by any of the lower reporting threshold 
options as a result of natural gas combustion, EPA has estimated in the 
economic analysis of the final rule that no additional reports on lead 
and lead compounds will be submitted solely as a result of natural gas 
combustion.
    Commenters assert that EPA underestimated the burden associated 
with the proposed rule because they believe that EPA's estimates of 
burden consider only those facilities expected to file reports under 
the proposed lower reporting thresholds. The commenters state that many 
facilities will be affected by the rule because they will have to make 
threshold determinations, even though they will not exceed the 
reporting threshold. The commenters contend that these facilities will 
incur the unit costs that EPA has quantified in the Economic Analysis 
for compliance determination and rule familiarization. The commenters 
contend that because the proposed thresholds are very low and material 
use varies from year to year, these determinations would occur 
annually, not just in the first year.
    In estimating the cost of the rule, EPA considered facilities that 
make threshold determinations but do not exceed the reporting 
threshold. EPA estimated the costs to facilities of determining whether 
a report must be filed for lead and/or lead compounds as part of 
``compliance determination.'' EPA agrees that a compliance 
determination will be made annually at all facilities with 10 or more 
employees that are in SIC codes subject to reporting under EPCRA 
section 313, and the economic analysis of the rule reflects this.
    Compliance determination should occur annually at all facilities 
with 10 or more employees that are in SIC codes subject to reporting 
under EPCRA section 313. In this respect, compliance

[[Page 4536]]

determination for lead and lead compounds is similar to compliance 
determination for all other EPCRA section 313 chemicals. However, lead 
and lead compounds are a small part of the list of over 600 EPCRA 
section 313 chemicals. Therefore, it is reasonable to expect that the 
typical incremental compliance determination costs specifically for 
lead and lead compounds at a lower reporting threshold would be less 
than current compliance determination costs for the entire list of 
EPCRA section 313 chemicals.
    Compliance determination costs are described in Chapter 4 of the 
economic analysis. The economic analysis of the final rule estimates 
that compliance determination for the changes in TRI reporting will 
take an average of 1.6 hours in the first year of reporting and 0.4 
hours in subsequent years. These estimates are incremental to the time 
currently required each year for compliance determination for other 
EPCRA section 313 chemicals. The lower burden hour estimate for 
subsequent years reflects the decline in burden hours after the 
necessary inputs to the threshold calculation are identified at each 
facility.
    EPA does not agree that facilities will incur ``rule 
familiarization'' costs after the first year of reporting, especially 
if these facilities do not exceed any applicable reporting thresholds. 
Rule familiarization is related to the time that facilities spend 
learning how to fill out the reporting form. Once a facility determines 
that a report is not required, the subsequent costs of reporting (rule 
familiarization, report completion, and mailing/recordkeeping) are not 
incurred. Facilities are expected to incur costs of rule 
familiarization only if they are reporting under EPCRA section 313 for 
the first time. At a minimum, rule familiarization involves reading the 
instructions to the Toxic Chemical Release Inventory Reporting Form R, 
however, it may also involve consulting EPA guidance documents, 
attending a training course, and/or calling the EPCRA technical 
hotline. In subsequent years, staff are already familiar with the 
requirements that apply to their facility, apart from any minor changes 
to interpretive guidance that may occur in the intervening year.

C. What are the Potential Benefits of this Proposal?

    In enacting EPCRA and PPA, Congress recognized the significant 
benefits of providing the public with information on toxic chemical 
releases and other waste management practices. EPCRA section 313 has 
empowered the Federal government, State governments, industry, 
environmental groups and the general public to participate in an 
informed dialogue about the environmental impacts of toxic chemicals in 
the United States. EPCRA section 313's publicly available data base 
provides quantitative information on toxic chemical releases and other 
waste management practices. Since the TRI program's inception in 1987, 
the public, government, and the regulated community have had the 
ability to understand the magnitude of chemical releases in the United 
States and to assess the need to reduce the uses and releases of toxic 
chemicals. TRI enables all interested parties to establish credible 
baselines, to set realistic goals for environmental progress over time, 
and to measure progress in meeting these goals over time. The TRI 
system is a neutral yardstick by which progress can be measured by all 
stakeholders.
    The information reported under EPCRA section 313 increases 
knowledge of the amount of toxic chemicals released to the environment 
and the potential pathways of exposure, improving scientific 
understanding of the health and environmental risks of toxic chemicals; 
allows the public to make informed decisions on where to work and live; 
enhances the ability of corporate leaders and purchasers to more 
accurately gauge a facility's potential environmental liabilities; 
provides reporting facilities with information that can be used to save 
money as well as reduce emissions; and assists Federal, State, and 
local authorities in making better decisions on acceptable levels of 
toxic chemicals in the environment.
    There are two types of benefits associated with reporting under 
EPCRA section 313: those resulting from the actions required by the 
rule (such as reporting and recordkeeping), and those derived from 
follow-on activities that are not required by the rule. Benefits of 
activities required by the rule include the value of improved knowledge 
about the release and waste management of toxic chemicals, which leads 
to improvements in understanding, awareness and decision-making. It is 
expected that this rule will generate such benefits by providing 
readily accessible information that otherwise would not be available to 
the public. The rule will benefit ongoing research efforts to 
understand the risks posed by lead and lead compounds and to evaluate 
policy strategies that address those risks.
    The second type of benefit derives from changes in behavior that 
may result from the information reported under EPCRA section 313. These 
changes in behavior, including reductions in releases of and changes in 
the waste management practices for toxic chemicals may yield health and 
environmental benefits. These changes in behavior come at some cost, 
and the net benefits of the follow-on activities are the difference 
between the benefits of decreased chemical releases and transfers and 
the costs of the actions needed to achieve the decreases.
    Commenters point out that EPA has not quantified the benefits of 
the proposed rule. The commenters assert that not quantifying the 
benefits of the rule severely inhibits the public's ability to evaluate 
and comment upon this proposed rule.
    EPA notes that the state of knowledge about the economics of 
information is not highly developed. Because of the inherent 
uncertainty in the subsequent chain of events following TRI reporting, 
EPA has not attempted to predict the exact changes in behavior that 
result from the information, or the resultant monetized benefits. EPA 
does not believe that there are adequate methodologies to make 
reasonable monetary estimates of either the benefits of the activities 
required by the proposed rule, or the follow-on activities. The 
economic analysis of the proposed rule, however, does provide a 
qualitative discussion along with illustrative examples of how the 
proposed rule will improve the availability of information on lead and 
lead compounds. EPA described how consumers, industry, the financial 
and business community, academics, environmental groups, communities, 
and the media are expected to use the results of TRI reporting on lead 
and lead compounds. Based on the number and variety of comments, it 
appears that this information was adequate to allow the public to 
evaluate and comment on the benefits of the proposed rule.
    A number of commenters request that EPA quantify the releases 
expected to be captured by the proposed rule and address whether a 
substantial majority of lead and lead compounds releases are already 
captured by current TRI reporting. Other commenters state that EPA 
cannot estimate the quantity of lead and lead compounds that are 
released or transferred without the additional data that would be 
collected by the rule. These commenters assert that estimates about 
releases or transfers would be ``fundamentally flawed'' due to a 
reliance on unsupported assumptions about facility operations, not on 
actual data. The commenters note that while it is possible to estimate 
how many facilities might be impacted

[[Page 4537]]

by having to report a particular substance, estimating quantities at a 
particular facility is extremely difficult because of differences in 
operations even among facilities in a narrowly-defined four-digit SIC 
code. The commenters express a concern that any release estimate made 
by EPA of an ``average'' facility is likely to be highly inaccurate and 
biased toward known sources of lead releases, and that those 
communities with large numbers of facilities with small releases would 
be adversely affected by this approach.
    EPA agrees with the commenters who describe the practical 
difficulties in making reasonable, reliable estimates of the quantity 
of lead and lead compounds that are released or transferred without the 
additional reporting data that would be collected by the rule. EPA has 
not estimated the total national releases to all media for this rule 
(and in previous TRI rules) because EPA believes that there is 
insufficient information on the numerous processes and associated waste 
management techniques in the affected sectors to generate a 
comprehensive release estimate.
    Existing data do not support estimates of releases and other waste 
management activities to multiple environmental media from the full 
range of facilities that may be affected by the rule because most of 
the data required for the analysis would only be available after the 
rule is in place. For the affected industry sectors, up-to-date multi-
media release estimates for facilities that would be affected by the 
rule do not exist. Even where release estimates are available for an 
industry sector, most are derived from national activity levels and 
emission factors rather than from facility-level information. To the 
extent that release estimates are available, they tend to cover only a 
single medium such as air. EPA does not believe that there is 
sufficient information to make reasonable predictions of the multi-
media releases and other waste management information that will be 
reported as a result of EPCRA section 313 rulemakings.
    Historical attempts to estimate the releases expected to be 
reported to TRI prior to actual reporting have been imprecise to the 
point of being misleading, particularly in respect to estimates of 
releases per report or per facility. EPA notes that there were various 
reports and studies about air emissions of toxic chemicals prior to 
TRI, but the collection of facility-level data showed that actual 
releases were much different from what had been anticipated. EPA has 
not seen any evidence to indicate that the TRI releases that will be 
reported as a result of the this action can be predicted any more 
accurately now than the quantities reported as a result of the original 
TRI rule could have been predicted prior to 1987.
    Aside from the general issue of uncertainty in the estimates of 
aggregate releases, predictions of releases per facility or per report 
(or dollars of reporting cost per pound of releases) are likely to be 
misleading due to the biases built into the estimates. The predicted 
number of reports (and thus costs) is generally an overestimate, since 
EPA's economic analyses use conservative estimates to avoid 
underestimating true costs. On the other hand, predictions of releases 
will tend to underestimate emissions, because while there may be 
information available on releases of some chemicals from some sectors, 
such estimates will not include other sources where releases are not 
identified until more detailed data (such as TRI data) are collected. 
Combining the two sets of estimates compounds the problem. Since 
estimated pounds of releases are underestimated and reports are 
overestimated, pounds per report are biased significantly downward. 
Likewise, estimates of dollars of reporting cost per pound of releases 
(which varies as the inverse of pounds per report) will be biased 
significantly upward.
    EPA does not believe that inaccurate or incomplete estimates of 
releases and other waste management activities would aid the decision-
making process for the rule. Therefore, EPA has not estimated the 
releases and other waste management activities that would be reported 
as a result of the rule.
    Commenters assert that the cost of the rule would outweigh the 
benefits because the proposed 10 pound reporting threshold for lead and 
lead compounds will not capture ``significant'' amounts of releases, 
while substantially burdening thousands of facilities.
    Although the reporting threshold for lead and lead compounds in 
this action is 100 pounds, EPA does not agree with the comment. The 
commenters do not define what constitutes ``significant'' amounts of 
releases of lead and lead compounds. Absent this definition, it is 
unclear what amount of unreported releases the commenters believe would 
justify the cost of additional reporting. The implication of the 
comment is that there is minimal benefit to any reporting that does not 
constitute a large proportion of total national releases. EPA does not 
agree. EPA notes that the inherent persistence, bioaccumulation, and 
toxicity of lead and lead compounds create concern about human health 
and environmental effects in even the smallest amounts or 
concentrations. EPA believes that information on small amounts of lead 
or lead compounds (either in absolute or relative terms) is important. 
Even if a single facility or industry is not responsible for a high 
percentage of total national loadings, the releases from that facility 
or industry may still be of concern to the public. The percentage of 
total national releases that an individual facility or industry 
represents does not reflect the potential human health and 
environmental effects of even small amounts of lead and lead compounds, 
especially when multiple facilities release lead and lead compounds 
that persist and bioaccumulate. EPA also believes that focusing 
exclusively on releases ignores the value of other data elements on TRI 
reporting form, such as quantities of waste otherwise managed on-site 
and transferred for off-site management and qualitative information on 
source reduction activities.
    Aside from the issue of whether comprehensive release estimates for 
such a rulemaking can reliably be predicted, EPA notes that pounds of 
releases and other waste management activities (even if known) are not 
a reasonable proxy for the benefits of the information being provided. 
This is because the benefits of an informational regulation are not 
systematically related to the magnitude of the data elements being 
reported. For example, automobile manufacturers are required to provide 
information about fuel economy on the stickers for new cars. Assuming 
that the quantity reported is a direct measure of the value of the 
information would lead to the mistaken conclusion that there is 100 
percent difference in the benefit of requiring the information to be 
provided on a car that gets 15 miles per gallon compared to another car 
that gets 30 miles per gallon. To use another example, nutritional 
labels are required on food packages. Assuming that the benefits of 
information provision are linearly related to the quantity that is 
reported would yield the conclusion that if one product has 6 grams of 
fat per serving and another has 2 grams, the benefit of the nutritional 
labeling requirement are three times higher for the former than the 
latter.
    One of the central purposes of TRI data is to inform the public 
about releases and other waste management of EPCRA section 313 listed 
toxic chemicals in their community and nationally so that the public 
can form its own conclusions about risks. The amount of releases and 
other waste

[[Page 4538]]

management activities that a community may find relevant or useful will 
vary depending on numerous factors specific to that community, such as 
the toxicity of the various chemicals, potential exposure to these 
toxic chemicals, and the number of other facilities in the area that 
release EPCRA section 313 listed toxic chemicals. Section 313(h) of 
EPCRA states that the data are ``to inform persons about releases and 
other waste management activities of toxic chemicals to the 
environment; to assist governmental agencies, researchers, and other 
persons in the conduct of research and data gathering; to aid in the 
development of appropriate regulations, guidelines, and standards; and 
for other similar purposes.'' Pounds of releases and other waste 
management activities reported does not measure how the data perform 
these functions, and thus is not a measure of benefits. EPA disagrees 
with the implicit assumption by commenters that the benefits of 
information from different facilities is strictly and systematically 
related to the quantity reported as being released. Finally, EPA notes 
that while the proposed reporting threshold for lead and lead compounds 
was 10 pounds, the final rule (and associated economic analysis) 
reflect a reporting threshold of 100 pounds. This further reduces the 
relevance of the comment.

D. What are the Potential Impacts of This Action on Small Entities?

    In accordance with the Regulatory Flexibility Act (RFA) and the 
Agency's longstanding policy of always considering whether there may be 
a potential for adverse impacts on small entities, the Agency has 
evaluated the potential impacts of this rule on small entities.
    This rule may affect both small businesses and small governments. 
No small non-profit organizations are expected to be affected by the 
rule. For the purpose of its small entity impact analysis for the final 
rule, EPA defined a small business using the small business size 
standards established by the Small Business Administration (SBA) at 13 
CFR part 121. [On October 1, 2000, the new SBA size standards for small 
businesses based on the North American Industry Classification System 
(NAICS) took effect (65 FR 30836, May 15, 2000). These replaced the 
previous size standards established under the Standard Industrial 
Classification (SIC) system. EPA has concluded that the conversion to 
the new classification system will have no substantive impact on the 
conclusions of the Agency's small entity impact analysis for this 
action (Ref. 53)]. EPA defined small governments using the RFA 
definition of jurisdictions with a population of less than 50,000. EPA 
analyzed the potential cost impact of the rule on small businesses and 
governments separately in order to obtain the most accurate assessment 
for each. EPA then aggregated the analyses for the purpose of 
determining whether it could certify that the rule will not have a 
``significant economic impact on a substantial number of small 
entities.'' RFA section 605(b) provides an exemption from the 
requirement to prepare a regulatory flexibility analysis for a rule 
where an agency makes and supports this certification statement. EPA 
believes that the statutory test for certifying a rule and the 
statutory consequences of not certifying a rule all indicate that 
certification determinations should be based on an aggregated analysis 
of the rule's impact on all of the small entities subject to it.
    Only those small entities that are expected to submit at least one 
report are considered to be ``affected'' for the purpose of the small 
entity analysis, although EPA recognizes that other small entities will 
conduct compliance determinations under lower thresholds. The number of 
affected entities will be smaller than the number of affected 
facilities, because many entities operate more than one facility. 
Potential small entity impacts were calculated for both the first year 
of reporting and subsequent years. First year costs are typically 
higher than continuing costs because firms must familiarize themselves 
with the requirements. Once firms have become familiar with how the 
reporting requirements apply to their operations, costs fall. EPA 
believes that subsequent year impacts present the best measure to judge 
the impact on small entities because these continuing costs are more 
representative of the costs firms face to comply with the rule.
    The incremental burden of the additional reporting at the facility 
level is low. This burden is associated with labor that will be 
expended by facility staff to conduct the reporting activities to file 
one TRI report. By statutory requirement, the smallest possible 
facility that could be affected by this action must have the equivalent 
of at least 10 full-time employees. On a yearly basis, this means that 
there are at least 20,000 labor hours expended at the smallest 
potentially affected facility (10 FTEs x 50 wks/year/employee x 40 
hours/wk = 20,000 labor hours/year). EPA estimates that typical 
reporting burdens as a result of this rule will be up to 110 hours per 
facility (in the first year of reporting for a first-time TRI 
reporter), and that in subsequent years typical reporting burden will 
be approximately 50 hours. Based on these reporting burdens, the 
average impact of TRI reporting ranges from 0.25 to 0.55 percent of 
available labor hours for the smallest facility affected by this rule. 
The impact would be even less for facilities with more than 10 full-
time employees, or for facilities that take less than the average time 
to report.
    EPA examined annual compliance costs as a percentage of annual 
company sales to assess the potential impacts of this rule on small 
businesses. Based on its estimates of additional reporting as a result 
of the rule, the Agency estimates that approximately 5,700 businesses 
will be affected by the rule, and that approximately 4,100 of these 
businesses are classified as ``small'' based on the applicable SBA size 
standards. EPA estimates that fewer than 250 small businesses 
(approximately 5% of all affected small businesses) will bear annual 
costs between 1-3% of annual revenues in the first reporting year, and 
that no small businesses will bear annual costs above 1% of annual 
revenues in subsequent reporting years. These results are not 
significantly different from those derived in the economic analysis of 
the proposed rule; the main difference is a ``non-zero'' result for the 
number of small businesses predicted to experience an annual cost 
impact above 1% of annual revenues in the first year of reporting. 
These estimates, and their derivation, are described in the economic 
analysis of the final rule (Ref. 46).
    A number of commenters submitted comments on EPA's methodology for 
assessing small entity impacts in the economic analysis of the proposed 
rule. One commenter asserts that the Agency's analysis of potential 
impacts of the proposed rule on small business is lacking because it 
does not examine the large number of industrial sectors that may be 
affected by this reporting requirement. The commenter states that EPA's 
findings about the widespread and persistent nature of lead in the 
environment are not in accord with the ``very limited effort'' to 
identify affected sectors (especially small business sectors).
    EPA disagrees with the commenter's characterization of the effort 
made to identify affected sectors. In the economic analysis for the 
proposed rule, EPA made quantitative estimates of the number of 
additional TRI reports that would be expected at four lower reporting 
thresholds for lead and lead compounds from industry groups that are 
subject to EPCRA section 313 and for which EPA could locate the 
information necessary to make

[[Page 4539]]

quantitative estimates of facility level lead usage. EPA also 
identified a number of industry groups which are also subject to EPCRA 
section 313, but for which EPA lacked data on lead throughput to 
generate quantitative estimates of additional reporting.
    In the proposed rule, and in a subsequent notice announcing public 
meetings, EPA solicited additional information to allow EPA to quantify 
the number of additional reports in all industry groups that are 
subject to EPCRA section 313. EPA fully considered information from the 
commenters on the potential for additional reporting from industries 
that were not identified in the economic analysis of the proposed rule, 
or for which EPA was unable to make quantitative estimates at the time 
of the proposal. As a result of the comments, EPA revised its estimates 
for a number of potentially affected industry groups. The revised 
estimates are described in Appendix A of the economic analysis of the 
final rule. While the estimates for some industry groups changed 
substantially as a result of the comments, EPA's estimate of the total 
number of additional reports remained relatively stable. At a 100 pound 
reporting threshold for lead and lead compounds, EPA estimates that 
approximately 9,800 facilities will submit additional reports.
    EPA's economic analysis of the proposed rule modeled the revenue 
characteristics of affected firms to evaluate the potential impact on 
small businesses. Commenters assert EPA's analysis produced biased 
results by combining manufacturing industries (SIC codes 20-39) that 
are unrelated in most aspects. Commenters assert that EPA made faulty 
assumptions by ``grouping together small business with large 
manufacturers.'' One commenter asserts that EPA's analysis considered 
the aggregate cost of the proposal to each industry group surveyed, 
ignoring individual businesses with costs above and below the aggregate 
value.
    In the economic analysis of the proposed rule EPA modeled revenues 
for small firms with low, medium and high revenues in the manufacturing 
industries (i.e., SIC codes 20-39). EPA's RFA/SBREFA guidance states 
that ``In assessing the impact of a rule on small businesses, it may be 
appropriate to analyze the rule's impact on each kind of business 
separately, particularly where the rule may impose significantly higher 
costs on some kinds of businesses than on others'' (Ref. 50). However, 
there is no guidance as to the specific SIC code level that is 
appropriate (e.g., 2-digit vs. 3-digit vs. 4-digit vs. 5-digit, etc.). 
For the small entity analysis of the proposed rule, EPA analyzed 
impacts separately for the following ``kinds of businesses'': mining, 
manufacturing, electric utilities, commercial hazardous waste 
treatment, chemical and allied products-wholesale, petroleum bulk 
terminals, and solvent recovery services. EPA does not believe that 
this approach biased the results of the small entity impact analysis 
for the proposed rule.
    EPA did not group small businesses together with large businesses 
in the manufacturing industry as the commenter asserts. EPA constructed 
separate revenue models for large firms and small firms. For small 
firms within each industry group, EPA compared typical reporting costs 
with the revenues available to small firms with low, medium, and high 
revenues. EPA's analysis was not based on an aggregate cost to each 
industry group, but rather on the cost to individual firms. For the 
economic analysis of the final rule, EPA developed revenue profiles at 
the 2-digit SIC code level (20, 21, 22, etc.) for small businesses 
within the manufacturing industries to provide for additional 
disaggregation. This approach was taken to address the comment that EPA 
would reach a different determination if impact estimates for the 
manufacturing SIC codes were presented at a greater level of 
disaggregation. Contrary to the comments on this issue, the 
disaggregated analysis does not change the ultimate conclusion about 
small entity impacts.
    In the small entity impact analysis for the proposed rule, revenues 
of potentially affected small businesses were modeled using revenue 
data for small businesses that own or operate facilities that currently 
report to TRI on any chemical. EPA developed separate revenue profiles 
based on ``small'' current filers and ``large'' current filers. Within 
these profiles, EPA looked at companies with low, medium, and high 
revenues. Commenters contend that EPA's use of current TRI filers as a 
representative cohort for estimating the proposed rule's impacts on 
small businesses is flawed since current TRI filers may not be 
representative of facilities that report to TRI for the first time as a 
result of the rule. The commenters assert that facilities reporting as 
a result of this rule are very different in terms of size and revenues 
from their counterparts that currently use lead, or other EPCRA section 
313 listed toxic chemicals, in amounts greater than 25,000 pounds. The 
commenters contend that current TRI filers are, for the most part, the 
largest members of their sectors with the highest revenues. As a 
result, the commenters contend that EPA underestimated the proposal's 
impact on small businesses. The commenters state a belief that an 
assessment of the rule's potential impact on small businesses should 
not be based upon its impact on current TRI filers. The commenters 
suggest an alternative methodology of assessing how the smallest 
facilities in each potentially impacted small business sector would be 
impacted by the proposed rule in order to make a SBREFA determination.
    EPA disagrees that using small businesses that own current TRI 
filers as a representative cohort for estimating the proposed rule's 
impacts on small businesses is flawed methodology for assessing whether 
the rule would have a significant economic impact on a substantial 
number of small entities. First, it should be noted that current TRI 
filers span the range of employment, from companies with 10 employees 
to those with thousands of employees. As noted in the economic analysis 
for the proposed rule, almost 70 percent of current TRI reporters are 
small businesses. Therefore, small businesses have substantial 
representation in current TRI reporting. Second, additional reporting 
on lead and lead compounds will not be limited to small facilities, or 
to facilities filing their first TRI reports. Additional reporting on 
lead is expected to come from facilities with a mix of size 
characteristics, including large facilities that currently report other 
EPCRA section 313 chemicals but not lead. Third, current TRI filers in 
the manufacturing industries tend to be found in capital-intensive 
industries rather than in labor-intensive industries. Based on EPA's 
research, it appears that most facilities that file additional lead 
reports will also be from capital-intensive industries like the ones 
that predominate in current TRI reporting. Since additional lead 
reporting will come mainly from: (1) Current filers (who file on other 
chemicals) and (2) new filers in capital-intensive industries, EPA 
believes that it is valid to assume that first-time filers under this 
rule will be like current filers in terms of employment and revenue.
    To evaluate the possibility that first-time TRI filers in the 
manufacturing sector would be so dissimilar to current TRI filers as to 
change EPA's small entity impact findings, EPA conducted a sensitivity 
analysis (Ref. 51) to estimate the potential impact on the smallest 
facilities in each potentially impacted small business sector for the 
proposed reporting threshold. This analysis estimated the average 
potential impact of the proposed rule on facilities

[[Page 4540]]

in various employment size classes within each of the twenty 2-digit 
manufacturing SIC codes (and certain 4-digit SIC codes). The analysis 
revealed that average potential impacts are higher for facilities with 
fewer employees and lower annual revenues, but the potential cost 
impact is still less than 1 percent of average annual revenues for 
every employment size class in every manufacturing SIC code.
    Even information submitted to EPA by industry does not indicate 
that a substantial number of small businesses would have costs above 1% 
of annual revenues. In an informal survey conducted by the IPC the 
Association Connecting Electronics Industries, IPC asked its member 
companies in the printed wiring board industry to indicate if the 
proposed rule would result in regulatory costs exceeding 1% of annual 
revenues (Ref. 52). IPC received 300 responses, of which 260 were from 
self-identified small businesses. Of these 260, only 5 claimed that the 
proposed rule would impose costs greater than 1% of their annual 
revenues. This survey indicates that less than 2% of affected small 
businesses in this sector believe that they would experience an 
economic impact of greater than 1% of annual revenues as a result of 
the proposed rule. Furthermore, IPC's survey was based on the proposed 
reporting threshold of 10 pounds. This final rule incorporates a 
reporting threshold of 100 pounds, which will result in less regulatory 
impact to facilities in this sector.
    To further address the issue of differing revenue characteristics 
between current and first-time TRI filers, EPA revised its method for 
modeling the revenues of affected small businesses. In the small entity 
impact analysis for the final rule, EPA modeled revenues of small 
first-time filers using revenue data for small businesses that own 
facilities that do not currently file TRI reports. EPA modeled revenues 
of small current filers using revenue data on small businesses that own 
current TRI-filing facilities. Contrary to the comments on this issue, 
using this method to model revenues does not change the ultimate 
conclusion about small entity impacts.
    A commenter asserts that EPA's conclusion about the impact of the 
rule on small businesses was based on an erroneous assumption about the 
percentage of additional reports that would be received from new 
filers. The commenter asserts that EPA ``seriously'' underestimated the 
number of first-time filers to TRI that would result from the proposed 
rule. The commenter notes that approximately 10% of printed wiring 
board facilities currently report to TRI and few of the facilities 
report for lead, but that this proposal would trigger lead reporting 
for virtually all companies. In this industry, approximately 80% to 90% 
would have to report to the TRI for the first time. The commenter notes 
that EPA estimated that first-time filers under the rule would comprise 
only 38.3% of affected manufacturing facilities.
    The estimate for first-time TRI filers cited by the commenter is an 
average for the entire manufacturing sector. For individual SIC codes 
within manufacturing (such as printed wiring boards), the percentage of 
first-time TRI filers may be higher or lower. For the economic analysis 
of the final rule, the estimate of first-time filers was revised based 
on an SIC code-by-SIC code approach that assumes current TRI filers 
will file the first additional reports in each SIC code, and that the 
remaining additional reports will be filed by facilities that are new 
to TRI reporting (i.e., first-time filers). Rather than using an 
average number of new filers for manufacturers as a class, this 
approach estimates the number of new filers at the 2-, 3-, or 4-digit 
SIC code level. Using the revised approach, the total estimated 
percentage of first-time filers increased to approximately 40% of all 
affected facilities, with substantial variation at the 2-digit SIC code 
level as indicated by the commenters. Therefore, EPA does not believe 
that the number of first-time filers was ``seriously'' underestimated 
in the economic analysis of the proposed rule.
    In assessing the potential impact of the rule on small entities, 
EPA searched for situations in which the annual cost of reporting for a 
business would exceed a small fraction of annual revenues. Commenters 
assert that 1% of annual sales (one of the indicator values used by 
EPA) is not a good measure of impacts on small businesses. The 
commenters assert that the 1% metric is arbitrary and argue that it may 
not be a good measure of impact across different industry sectors. The 
commenters state that some industries may have profits that are only a 
few percent of total revenue, in which case, costs that are close to 
one percent of revenue would be a very large percent of profit, while 
other industries may have profits that are a much higher percent of 
revenue.
    Contrary to the commenters' claim, EPA did justify its choice of 
revenue-based impact metric for assessing small entity impacts. As EPA 
stated at 64 FR 42238, ``EPA used annual compliance costs as a 
percentage of annual company sales to assess the potential impacts on 
small businesses of this proposed rule. EPA believes that this is a 
good measure of a firm's ability to afford the costs attributable to a 
regulatory requirement, because comparing compliance costs to revenues 
provides a reasonable indication of the magnitude of the regulatory 
burden relative to a commonly available measure of a company's business 
volume. Where regulatory costs represent a small fraction of a typical 
firm's revenue (for example, less than 1%, or not greater than 3%), EPA 
believes that the financial impacts of the regulation may be considered 
not significant.''
    The commenters suggest that EPA should use profits as a measure of 
impact. EPA, however, believes that there are several advantages to the 
use of revenue data. The advantage of using revenue to measure impacts 
is that it is a stable, easily accessible, and easily understood 
measure which provides a basis for comparing this rule to other rules. 
Unlike profit information, the definition is consistent and not subject 
to the widely varying accounting definitions and interpretations of 
terms that affect ``profit'' measures. Another advantage is that 
revenue data, unlike profit data, are widely available. The proportion 
of firms for which revenue data are available generally greatly exceeds 
the proportion of firms for which profit data are available. Many 
information sources, including the Census of Manufactures, collect and 
publish revenue data but not profit data.
    Furthermore, revenue data are easily understood. For example, if 
the impact of compliance costs on a firm is 1% of revenue, a firm would 
need to raise its prices 1% to cover the costs of the regulation. This 
is a clear, easy to understand measure that can help decision-makers 
determine whether additional measures to reduce the impact of a 
regulation are warranted. In addition, EPA has a long history of using 
the relationship between the annual cost of compliance with a 
regulation and total annual revenue of the firm to determine whether a 
regulation may have a significant economic impact on substantial number 
of small entities.
    EPA believes that the revenue-based impact calculation used in the 
analysis of this rule is preferable to a profit-based calculation 
because it is simple to apply and based on readily available data, 
which allows consistent application of the methodology from rule to 
rule. Although the commenters suggest other metrics such as profit 
margins, they do not provide any indication of how this data could be 
obtained or what impact levels would indicate a ``significant'' impact. 
The commenters note that profit

[[Page 4541]]

margins are variable, but do not provide profit margin data for all 
affected industry sectors.
    In addition to small businesses, the rule is also expected to 
affect certain small governments. To assess the potential impacts of 
the final rule on small governments, EPA used annual compliance costs 
as a percentage of annual government revenues to measure potential 
impacts. Similar to the methodology for small businesses, this measure 
was used because EPA believes it provides a reasonable indication of 
the magnitude of the regulatory burden relative to a government's 
ability to pay for the costs, and is based on readily available data. 
EPA estimates that 8 publicly owned electric utility facilities, 
operated by a total of 8 municipalities, may be affected by the rule. 
Of these, an estimated 7 are operated by small governments (i.e., those 
with populations under 50,000). It is estimated that none of these 
small governments will bear annual costs greater than 1% of annual 
government revenues in the first or subsequent reporting years. 
Therefore, the total number of small entities with impacts above 1% of 
revenues does not change when the results are aggregated for all small 
entities (i.e., small businesses, small governments, and small 
organizations) because only certain small businesses are expected to 
experience impacts above 1% of revenues in any year.

VIII. What are the References Cited in this Final Rule?

    1. Response to Comments Received on the August 3, 1999 Proposed 
Rule (64 FR 42222) to Lower the EPCRA Section 313 Reporting Thresholds 
for Lead and Lead Compounds. Office of Information Analysis and Access, 
U.S. Environmental Protection Agency, Washington, DC (2000).
    2. Syracuse Research Corporation. The Environmental Fate of Lead 
and Lead Compounds. Prepared for David G. Lynch, U.S. Environmental 
Protection Agency, under contract number SRC 68-D5-0012, March 1999.
    3. Rand, GM. Fundamentals of Aquatic Toxicology, 2nd. Ed. Taylor 
Francis, Washington, DC, (1995), 1125 pp.
    4. Meylan, WM, Howard, PH, and Boethling, RS. ``Improved Method for 
Estimating Bioconcentration Factor from Octanol/Water Partition 
Coefficient'' Environ. Toxicol. Chem. 18:664-672.
    5. Merlini, M. and Pozzi, A. 1977. Lead and Freshwater Fishes. Part 
1. Lead Accumulation and Water pH. Environ. Pollut. 12:167-172.
    6. USEPA/OPPT. Bioaccumulation/Bioconcentration Assessment for Lead 
and Lead Compounds. Jerry Smrchek, Ph.D., Biologist, Existing Chemicals 
Assessment Branch, Risk Assessment Division, March 31, 1999.
    7. USEPA. Ambient Water Quality Criteria for Lead. 1984. EPA 440/5-
84-027, Office of Water, U.S. Environmental Protection Agency, 
Washington, D.C., 1985, 81 pp.
    8. ATSDR. Draft Toxicological Profile for Lead. U.S. Department of 
Health and Human Services, Public Health Service, Agency for Toxic 
Substances and Disease Registry, August 1997.
    9. USEPA/OPPT. Risk Analysis to Support Standards for Lead in 
Paint, Dust, and Soil--Volume 1. U.S. Environmental Protection Agency, 
Office of Pollution Prevention and Toxics, Washington DC, EPA 747-R-97-
006, June, 1998.
    10. USEPA/ECAO. Air Quality Criteria for Lead--Volume 1 of IV. U.S. 
Environmental Protection Agency, Environmental Criteria and Assessment 
Office, Research Triangle Park, NC, EPA-600/8-83/028aF, June 1986.
    11. USEPA/OIA. Technical Information Package for Lead. Internet 
site: http://www.epa.gov/oiamount/tips/ lead2.htm. Maintained by the 
U.S. Environmental Protection Agency, Office of International Affairs. 
Downloaded March 1999.
    12. Davis A, Ruby M, and Bergstrom, P. Factors Controlling Lead 
Bioavailability in the Butte Mining District, Montana, USA 
Environmental Geochemistry and Health 1994; 16(3/4):147-157.
    13. Davis, A, Drexler, J, Ruby, M, and Nicholson, A. 
Micromineralogy of Mine Wastes in Relation to Lead Bioavailability, 
Butte, Montana Environ Sci Technology 1993 Mar 16; 27(7):1415-1425.
    14. Rabinowitz, MB, et. al., Kinetic Analysis of Lead Metabolism in 
Healthy Humans. Journal of Clinical Investigation. 1976, 58:260-270.
    15. USEPA, OPPT, 1999. Response to Comments Received on the January 
5, 1999 Proposed Rule (64 FR 688) to Lower the EPCRA Section 313 
Reporting Thresholds for Persistent, Bioaccumulative Toxic (PBT) 
Chemicals and to Add Certain PBT Chemicals to the EPCRA Section 313 
List of Toxic Chemicals and Response to Comments Received on the May 7, 
1997 Proposed Rule (62 FR 24887) to Add a Category of Dioxin and 
Dioxin-like Compounds to the EPCRA Section 313 List of Toxic Chemicals. 
Office of Pollution Prevention and Toxics, U.S. Environmental 
Protection Agency, Washington, DC.
    16. USEPA, OPPT. Economic Analysis of the Proposed Rule to Modify 
the Reporting Requirements for Lead and Lead Compounds under EPCRA 
Section 313, May 1999.
    17. HHS. Eighth Report on Carcinogens, 1998 Summary, US Department 
of Health and Human Services, National Toxicology Program, 1998.
    18. USEPA. Integrated Risk Information System (IRIS). ``Arsenic, 
Inorganic,'' at http://www.epa.gov/iris/subst/0278.htm. Downloaded June 
2000.
    19. Masterton, WL, Slowinski, EJ. Chemical Principles, 3rd. Ed. 
Saunders, WB. Philadelphia, PA (1973), pp 29-30.
    20. Ihde, AJ. The Development of Modern Chemistry. Dover 
Publications, Inc. Garden City, NY (1984), pp 499-507.
    21. DeVito, S.C. ``Absorption Through Cellular Membranes.'' In: 
Handbook of Property Estimation Methods for Chemicals, Environmental 
and Health Sciences (Chapter 11); Boethling, RS, and Mackay, D. (Eds.), 
Lewis Publishers, New York, NY (2000), pp 261-278.
    22. Roane, TM, and Pepper, IL. ``Microorganisms and Metal 
Pollutants.'' In: Environmental Microbiology (Chapter 17); Maier, RM, 
Pepper, IL, and Gerba, CP. (Eds.), Academic Press, New York, NY (1999), 
pp 403-423.
    23. Ogen, S, Rosenbluth, S, Eisenberg, A. 1967. ``Food Poisoning 
Due to Barium Carbonate in Sausage.'' Isr. J. Med. Sci., 3:565-568.
    24. HSDB 2000. Hazardous Substances Data Bank: record on Lead 
(chemical abstracts #7439-92-1). National Library of Medicine, 
Bethesda, MD.
    25. Goyer, RA. ``Toxic Effects of Metals.'' In: Casarett & Doull's 
Toxicology, the Basic Science of Poisons (Chapter 23), 5th Edition, 
Klaassen, CD. (Ed), McGraw Hill, New York, NY (1996), pp 691-736.
    26. HSDB 2000. Hazardous Substances Data Bank: record on tetraethyl 
lead (chemical abstracts #78-00-2). National Library of Medicine, 
Bethesda, MD. (See section titled Metabolism/Pharmacokinetics; 
Metabolism/Metabolites).
    27. Malius, DC, and Ostrander, GK. 1991. ``Perspectives in Aquatic 
Toxicology.'' Ann. Rev. Pharmacol. Toxicol., 31:371-399.
    28. Keeton, WT. ``Nutrient Procurement and Processing.'' In: 
Biological Sciences, 2nd Edition, W.W. Norton and Company, Inc., New 
York, NY. (1972), pp 161-164.
    29. USEPA/ORD. Air Quality Criteria for Lead. Research Triangle 
Park, NC. EPA Office of Research and Development, Office of Health and

[[Page 4542]]

Environmetnal Assessment. 1986. EPA 600/8-83-028bF.
    30. Bondarenko, GP. 1968. An experimental study of the solubility 
of galena in the presence of fulvic acids. Geochem. Int. 5:525-531.
    31. Lowering, TG. (Ed), 1976. Lead in the Environment. Washington, 
DC: US Department of the Interior, Geological Survey; Geological Survey 
professional paper no. 957. S/N 024-001-02911-1.
    32. OECD. Harmonized Integrated Hazard Classification System for 
Human Health and Environmental Effects of Chemical Substances.
    33. May, TW, and McKinney, GL. 1981. Cadmium, Lead, Mercury, 
Arsenic and Selenium Concentrations in Freshwater Fish, 1976-77 
National Pesticides Monitoring Program. Pesticides Monitoring Journal 
15:14-38.
    34. White, JR, and Driscol, CT. 1985. Lead cycling in an Acidic 
Adirondack Lake. Environ. Sci. Technol. 19:1182-1187.
    35. Zhuang, Y, Allen, HE, Fu, G. 1994. Environ. Toxicol. Chem, 13: 
717-724.
    36. Mahony, JD, Di Toro, DM, Gonzalez, AM, Curto, M, Dilg, M, De 
Rosa, LD, and Sparrow, LA. 1996. Partitioning of Metals to Sediment 
Organic Carbon. Environ Toxicol Chem. 15:2187-2197.
    37. Eisler, R. 1988. Lead Hazards to Fish, Wildlife, and 
Invertebrates: a Synoptic Review. Biological Report 85(1.14) 
Contaminant Hazard Reviews Report No. 14, U.S. Fish and Wildlife 
Service, U.S. Department of the Interior, Laurel, MD. 134 pp.
    38. Reddy, KJ, Wang, L, and Gloss, SP. 1995. Solubility and 
mobility of copper, zinc and lead in acidic environments. Plant and 
Soil 171:53-58.
    39. Wang, EX, and Benoit, G. 1996. Mechanisms controlling the 
mobility of lead in the spodosols of a northern hardwood forest 
ecosystem. Environ Sci Technol 30: 2211-2219.
    40. Chuan, MC, Shu, GY, and Liu, JC. 1996. Solubility of heavy 
metals in a contaminated soil: effects of redox potential and pH. 
Water, Air and Soil Pollution 90:543-556.
    41. Murray, K, Bazzi, A, Carter, C, Elhart, A, Harris, A, Kopec, M, 
Richardson, J, and Socol, H. 1997. Distribution and mobility of lead in 
soils at an outdoor shooting range. J Soil Contamination 6:79-93.
    42. Laperche, V, Logan, TJ, Gaddam, P, and Traina, SJ. 1997. Effect 
of apatite amendments on plant uptake of lead from contaminated soil. 
Environ Sci Technol 31: 2745-2753.
    43. Zimdahl, RL, Skogerboe, RK. 1977. Behavior of Lead in Soil. 
Environ Sci Technol. 11:1202-1207.
    44. Mackay, D, DiGuardo, A, Paterson, S, and Cowan, CE. 
``Evaluating the Environmental Fate of a Variety of Types of Chemicals 
Using the EQC Model.'' Environ. Toxicol. Chem. v. 15, (1996), pp. 1627-
1637.
    45. Newsome, LD, Nabholz, JV, Kim, A. ``Designing Aquatically Safer 
Chemicals.'' In: Designing Safer Chemicals; Green Chemistry for 
Pollution Prevention (Chapter 9), DeVito, SC, and Garrett, RL. (Eds.), 
ACS Symposium Series 640, American Chemical Society, Washington, DC 
(1996) pp 172-193.
    46. USEPA, OPPT. Economic Analysis of the Final Rule to Modify the 
Reporting Requirements for Lead and Lead Compounds under EPCRA Section 
313, October 2000.
    47. USEPA, OAQPS. Locating and Estimating Air Emissions from 
Sources of Lead and Lead Compounds. EPA-454/R-98-006. May 1998.
    48. USEPA, OAQPS. Study of Hazardous Air Pollutant Emissions from 
Electric Utility Steam Generating Units B Final Report. EPA-453/R-98-
004b. February 1998.
    49. Chao, Sherman, Crippend, Karen, Janos, Alan. Analysis of Trace 
Level Compounds in Natural Gas. Gas Research Institute. June 1999.
    50. USEPA, OP/RMD. Revised Interim Guidance for EPA Rulewriters: 
Regulatory Flexibility Act as Amended by the Small Business Regulatory 
Enforcement Fairness Act, March 29, 1999.
    51. USEPA, OPPT. Note from Cody Rice (OPPT/EETD) to Angela Hofmann 
(OPPTS/RCS) regarding RFA Certification of the TRI lead rule, March 16, 
2000.
    52. Comment C-812 in Docket No. OPPTS-400140 (Lead and Lead 
Compounds; Lowering of Reporting Thresholds; Community Right-to-Know 
Toxic Chemical Release Reporting; Proposed Rules, 64 FR 42221 (Aug. 3, 
1999)).
    53. USEPA, OPPT. Note from Cody Rice (OPPT/EETD) to Angela Hofmann 
(OPPTS/RCS) regarding the Impact of SBA's Conversion for SIC to NAICS 
on the TRI Lead Rule, November 3, 2000.

IX. Regulatory Assessment Requirements

A. What is the Determination Under Executive Order 12866?

    Under Executive Order 12866, entitled ``Regulatory Planning and 
Review'' (58 FR 51735, October 4, 1993), it has been determined that 
this is a ``significant regulatory action''. This action was submitted 
to the Office of Management and Budget (OMB) for review, and any 
substantive changes made during that review have been documented in the 
public version of the official record.
    EPA's cost-benefit analysis for the proposed rule was contained in 
a document entitled Economic Analysis of the Proposed Rule to Modify 
Reporting of Lead and Lead Compounds Under EPCRA Section 313 (Ref. 16). 
The economic analysis contains a quantitative estimate of the costs and 
a qualitative discussion of the benefits of the proposed rule. This 
document, and its supporting documentation, were included in the public 
docket for review and comment. EPA has prepared an economic analysis of 
the impact of this final rule, which is contained in a document 
entitled Economic Analysis of the Final Rule to Modify Reporting of 
Lead and Lead Compounds under EPCRA Section 313 (Ref. 42). This 
document is available as part of the public version of the official 
record for this action, and is briefly summarized in Unit VII.
    Commenters assert that the proposed rule did not meet Executive 
Order 12866 requirements to consider costs and benefits, including the 
alternative of not regulating. The commenters assert that the Agency 
has not given adequate consideration to the baseline option of existing 
TRI reporting thresholds of 25,000 and 10,000 pounds, under which EPA 
has received reporting on release and other waste management of over 
one billion pounds of lead and lead compounds per year. The commenters 
assert that the alternative of the current reporting thresholds of 
25,000 and 10,000 pounds is generally not included in the text and 
tables of the preamble and Economic Analysis.
    EPA did consider the option of not regulating, and addressed what 
would happen in the absence of this rule. As EPA noted in the Federal 
Register notice for the proposed rule, ``If EPA were not to take this 
proposed action to lower reporting thresholds, the market failure (and 
the associated social costs) resulting from the limited information on 
the release and disposition of lead and lead compounds would continue'' 
(64 FR 42237). The discussion of costs and benefits in the economic 
analysis and preamble are all relative to the baseline of not 
regulating beyond the current reporting thresholds for lead and lead 
compounds. Chapter 6 of the economic analysis of the proposed rule 
contains a discussion of current reporting on lead and lead compounds 
at existing reporting thresholds, as well as a discussion of 
information that would be collected as a result of the proposed rule. 
Furthermore, current TRI

[[Page 4543]]

reporting on lead and lead compounds was summarized in Tables A-3 and 
A-4 of the economic analysis of the proposed rule.
    Commenters assert that EPA has not met requirements of Executive 
Order 12866 because EPA has not quantified benefits of the proposed 
rule and has not estimated the amount of releases expected to be 
reported.
    EPA believes that the proposal is consistent with Executive Order 
12866, because EPA proposed the regulation upon a reasoned 
determination that the benefits justify the costs. The commenters imply 
that EPA must quantify benefits to comply with Executive Order 12866. 
However, Executive Order 12866 recognizes that it may not be feasible 
to derive quantitative estimates of benefits in all cases. Section 
(1)(a) of Executive Order 12866 states that ``Costs and benefits shall 
be understood to include both quantifiable measures (to the fullest 
extent that these can be usefully estimated) and qualitative measures 
of costs and benefits that are difficult to quantify, but nevertheless 
essential to consider.'' The Executive Order goes on to state in 
section (1)(b)(6) that ``Each agency shall assess both the costs and 
the benefits of the intended regulation and, recognizing that some 
costs and benefits are difficult to quantify, propose or adopt a 
regulation only upon a reasoned determination that the benefits of the 
intended regulation justify its costs.'' EPA's economic analysis has 
addressed the costs of the proposal in a quantified manner and the 
benefits in a qualitative manner. Because the state of knowledge about 
the economics of information is not highly developed, EPA has not 
attempted to quantify the benefits of the rule as monetized net 
benefits. EPA notes that Executive Order 12866 does not require that 
benefits be quantified for every regulation, or that agencies should 
predict the answers to a data collection (in this case, the ``per 
facility'' releases and other waste management of lead and lead 
compounds) prior to the actual collection of the data.
    EPA notes that comparing the cost of the reporting to the quantity 
of releases that would be reported does not compare costs and benefits. 
Section 313(g) of EPCRA states that the data are intended to provide 
information to the Federal, State, and local governments and the 
public, including citizens of communities surrounding covered 
facilities, to inform persons about releases of toxic chemicals to the 
environment; to assist governmental agencies, researchers, and other 
persons in the conduct of research and data gathering; to aid in the 
development of appropriate regulations, guidelines, and standards; and 
for other similar purposes. The quantity of releases reported does not 
measure how well the data perform these functions, and thus releases 
are not a measure of benefits. The benefits of the rule include 
improvements in understanding, awareness, and decision making related 
to the provision of information. Even if reliable estimates of releases 
were possible, pounds of releases would not measure the value of the 
information provided. Improvements in understanding are not measured in 
pounds, nor are improvements in awareness or decision making.
    While it is not possible to quantify the benefits of the rule with 
monetized estimates, EPA has qualitatively examined the benefits of the 
rule. Based on this review, EPA believes that the benefits provided by 
the information to be reported under this rule will significantly 
outweigh the costs. Upon review of this evidence, EPA has made a 
reasoned determination that the benefits of the regulation justify its 
costs. Therefore, EPA believes it has followed the principles and met 
the requirements of Executive Order 12866.

B. What is the Determination Under the Regulatory Flexibility Act?

    Pursuant to section 605(b) of the Regulatory Flexibility Act (RFA) 
(5 U.S.C. 601 et seq.), the EPA Administrator hereby certifies that 
this final rule will not have a significant economic impact on a 
substantial number of small entities. The factual basis for this 
determination is presented in the small entity impact analysis prepared 
as part of the Economic Analysis for this final rule (Ref. 46), which 
is discussed in detail in Unit VII. and contained in the public version 
of the official record for this rule. Further support for this 
determination can be found in the sensitivity analysis (Ref. 51) that 
was conducted to assess the analytical methods used in the small entity 
impact analysis of the proposed rule. Information relating to this 
determination has been provided to the Chief Counsel for Advocacy of 
the Small Business Administration, and is included in the public 
version of the official record for this rulemaking. The following is a 
brief summary of the Agency's factual basis for this certification.
    For the purpose of analyzing potential impacts on small entities, 
EPA used the RFA definition of small entities in section 601(6) of the 
RFA. Under this section, small entities include small businesses, small 
governments, and small non-profit organizations. [On October 1, 2000, 
the SBA size standards for small businesses based on the North American 
Industry Classification System (NAICS) took effect (65 FR 30836, May 
15, 2000). These replaced the previous size standards established under 
the Standard Industrial Classification (SIC) system. EPA has concluded 
that the conversion to the new classification system will have no 
substantive impact on the conclusions of the Agency's small entity 
impact analysis for this action (Ref. 53)]. EPA defined a small 
business using the small business size standards established by the 
Small Business Administration (SBA), which are generally based on the 
number of employees or annual sales/revenue a business in a particular 
industrial sector has. EPA defined small governments using the RFA 
definition of jurisdictions with a population of less than 50,000. No 
small non-profit organizations are expected to be affected by this 
final rule.
    EPA estimates that approximately 4,100 small businesses will be 
affected by the rule. The incremental burden of the additional 
reporting at the facility level is associated with labor that will be 
expended by facility staff to conduct reporting activities. Based on 
typical reporting burdens of approximately 110 hours (in the first year 
of reporting for a first-time TRI reporter) and 50 hours in subsequent 
years, the impact of this action ranges from 0.25 to 0.55 percent of 
available labor hours for the smallest affected facility. The impact 
would be even less for facilities with more than 10 full-time 
employees, or for those that take less than the average amount of time 
to report.
    EPA estimates that the final rule would have an annual cost impact 
between 1-3% of annual revenues on fewer than 250 small businesses 
(approximately 5% of all affected small businesses) in the first year 
only. After the first year of reporting, the annual cost impact as a 
percentage of annual revenues is estimated to be below 1% for all 
affected small entities.
    Commenters assert that this rule will have significant impacts on 
small businesses, and that EPA improperly certified the proposed rule. 
The commenters assert that a Small Business Regulatory Enforcement 
Fairness Act (SBREFA) panel must be completed to determine the ``true'' 
impact of the proposed rule on small businesses.
    EPA believes that its certification of the proposed rule as not 
having a significant economic impact on a substantial number of small 
entities was proper. In the Federal Register notice

[[Page 4544]]

for the proposed rule, EPA described a quantitative small entity impact 
analysis that EPA placed in the official version of the public record. 
The results of this analysis indicated that the proposed rule would not 
have a significant economic impact on a substantial number of small 
entities. Based on public comments, EPA revised this quantitative 
analysis and arrived at the same conclusion for the final rule. 
Furthermore, EPA notes that while the proposed reporting threshold for 
lead and lead compounds was 10 pounds, this final rule incorporates a 
reporting threshold of 100 pounds. This threshold further reduces the 
potential regulatory impact on small entities as indicated in the 
economic analysis of the final rule.
    EPA does not agree with the comment that a SBREFA panel must be 
completed to determine whether this, or any, proposed rule will have a 
significant economic impact on a substantial number of small entities. 
SBREFA amended the Regulatory Flexibility Act (RFA) to require EPA to 
convene a Small Business Advocacy Review Panel for any proposed rule 
for which EPA is required to prepare an initial regulatory flexibility 
analysis (IRFA). The RFA requires that EPA prepare an IRFA for all 
rules for which EPA is required by statute to publish a notice of 
proposed rulemaking unless the agency certifies that the rule ``will 
not, if promulgated, have a significant economic impact on a 
substantial number of small entities.'' The panel is an additional 
means for small entities to participate in the rulemaking process, but 
the certification provision of the RFA as amended by SBREFA indicates 
that panels are not appropriate for every rulemaking. The panel 
requirement only applies to proposed rules that the Agency ultimately 
determines will not be certified under the RFA.
    Commenters also assert that EPA failed to provide a ``meaningful'' 
opportunity for small businesses to participate in the rulemaking 
process. The commenters asserted than that EPA did not conduct outreach 
to small businesses prior to the proposal, and that any outreach after 
rule proposal is inadequate and cannot remedy EPA's ``lack of 
outreach'' to small entities early in the regulatory development 
process. The commenters assert that ``EPA's failure to contact small 
business sectors early in the rulemaking process'' led to ``significant 
flaws'' in EPA's SBREFA determination because it failed to consider 
``more than two dozen small business sectors that would be impacted by 
the proposed rule'' and failed to consider the significance of the 
impact on small businesses. Specifically the commenters mention printed 
circuit board manufacturers, metal finishers, foundries, and dentists 
as affected sectors. As a result, the commenters contend that the 
Agency did not comply with SBREFA, and violated the analytical and 
outreach requirements of the RFA. The commenters also contend that EPA 
did not comply with the Agency's own internal guidance related to RFA/
SBREFA compliance. One commenter contends that EPA's failure to conduct 
appropriate outreach misled the Agency to certify that the rule has no 
significant impact on small business. Therefore, the commenter suggests 
that the EPA conduct additional outreach with small business, followed 
by a thorough SBREFA panel process. The commenter contends that 
outreach to small business would have revealed that the proposed rule 
affects more than ``two dozen small business sectors that the agency 
failed to consider.'' As one example, the commenter asserts that 
dentists would have to report because they accumulate lead in the form 
of used x-ray film backing that they store and recycle. The commenter 
also mentions metal finishing and the printed circuit board industry.
    EPA complied with internal guidance and the requirements of the RFA 
as amended by SBREFA and conducted its analysis in accord with the 
Agency's internal guidance. EPA's actions provided a meaningful 
opportunity for small businesses to participate in the rulemaking 
process. EPA initially alerted the potentially affected community to 
EPA's intention to review lead and lead compounds for lower reporting 
thresholds in the proposed rule to lower the EPCRA section 313 
reporting threshold for certain PBT chemicals that are subject to 
reporting under EPCRA section 313 (64 FR 688). That Federal Register 
notice stated that ``EPA is aware of additional available data that may 
indicate that lead and/or lead compounds meet the bioaccumulation 
criteria discussed in this proposed rule. EPA intends to review these 
additional data to determine if lead and/or lead compounds should be 
considered PBT chemicals and whether it would be appropriate to 
establish lower reporting thresholds for these chemicals'' (64 FR 717, 
January 5, 1999). As part of the PBT rulemaking process, EPA held three 
public meetings in San Francisco, CA; Chicago, IL; and Washington, DC. 
Numerous commenters on the PBT rule requested that EPA classify lead 
and lead compounds as PBT chemicals.
    EPA published a notice of proposed rulemaking for lead and lead 
compounds on August 3, 1999. EPA requested comment on this rulemaking 
and provided an initial 45 day comment period. Subsequently, EPA 
extended the comment period twice for a total of 90 additional days. In 
addition, EPA held public meetings with special emphasis on potential 
small business impacts in Los Angeles, CA; Chicago, IL; and Washington, 
DC. EPA also met with representatives of small business trade 
organizations who expressed a desire for additional meetings.
    EPA notes that a number of small businesses participated in the 
rulemaking process by attending public meetings and submitting comments 
on the proposed rule. EPA has considered these comments and updated its 
economic analysis with information provided by these commenters. EPA 
believes that these activities, along with the written public comment 
process, provided ample opportunities for small businesses to 
participate in the rulemaking process.
    EPA does not agree that its rulemaking process led to significant 
flaws in EPA's certification that the proposed rule would not, if 
promulgated, have a significant economic impact on a substantial number 
of small businesses. EPA conducted an extensive economic analysis that 
included a quantitative small entity impact analysis. EPA made this 
analysis available as part of the public record for the rulemaking. The 
public comment process has provided an opportunity for small businesses 
to comment on this analysis, and to provide additional information to 
refine this analysis. Further, even though EPA extended the public 
comment period twice and held three public meetings, EPA did not 
receive additional information that would lead it to change its 
determination.
    Although some commenters assert that EPA failed to identify certain 
potentially affected sectors leading to a flawed certification, EPA 
does not agree. EPA conducted an extensive economic analysis. 
Specifically, EPA did identify printed circuit board manufacturers, 
metal finishers, foundries, and other industries as potentially 
affected sectors in the economic analysis of the proposed rule. 
Dentists were not identified as potentially affected because they are 
not in a SIC code that is subject to TRI reporting. EPA cannot evaluate 
the accuracy of generic comments that assert EPA missed potentially 
affected industries when commenters do not identify these industries by 
name, or provide evidence to support the assertion for each additional 
identified industry. If EPA failed to identify certain sectors as

[[Page 4545]]

potentially affected, this a reflection of the lack of publicly 
available information on lead and lead compounds. The lack of publicly 
available information on lead and lead compounds speaks more to the 
need for the rule than to the quality of EPA's analysis.
    In conclusion, EPA believes that it has followed the requirements 
of the RFA and that it has properly certified that the rule will not 
have a significant impact on a substantial number of small entities.

C. What is the Determination Under the Paperwork Reduction Act?

    The information collection requirements contained in this final 
rule have been submitted to OMB under the Paperwork Reduction Act (PRA) 
(44 U.S.C. 3501 et seq.), and in accordance with the procedures at 5 
CFR 1320.11. OMB has approved the existing reporting and recordkeeping 
requirements for the EPA Toxic Chemical Release Inventory Form R (EPA 
Form No. 9350-1), supplier notification, and petitions under OMB 
Control No. 2070-0093 (EPA ICR No. 1363). EPA has prepared an amendment 
(EPA ICR No. 1363.11) to the existing Information Collection Request 
(ICR) to include the burden associated with lower reporting thresholds 
for lead and lead compounds. A copy may be obtained from Sandy Farmer, 
Office of Information Collections, U.S. Environmental Protection Agency 
(2137), 1200 Pennsylvania Ave., NW., Washington, DC 20460, by calling 
(202) 260-2740, or electronically by sending an e-mail message to 
``<a href="/cdn-cgi/l/email-protection#e88e899a858d9ac69b89868c91a88d9889c68f879e"><span class="__cf_email__" data-cfemail="432522312e26316d30222d273a032633226d242c35">[email protected]</span></a>.''
    An Agency may not conduct or sponsor, and a person is not required 
to respond to a collection of information subject to OMB approval under 
the PRA, unless a currently valid OMB control number is displayed. The 
OMB control numbers for EPA's regulations, after initial publication in 
the Federal Register, are maintained in a list at 40 CFR part 9. The 
information requirements contained in this final rule are not effective 
until OMB approves them.
    EPCRA section 313 (42 U.S.C. 11023) requires owners or operators of 
certain facilities manufacturing, processing, or otherwise using any of 
over 600 listed toxic chemicals and chemical categories in excess of 
the applicable threshold quantities, and meeting certain requirements 
(i.e., at least 10 Full Time Employees or the equivalent), to report 
certain release and other waste management activities for such 
chemicals annually. Under PPA section 6607 (42 U.S.C. 13106), 
facilities must also provide information on recycling and other waste 
management data and source reduction activities. The regulations 
codifying the EPCRA section 313 reporting requirements appear at 40 CFR 
part 372. Respondents may designate the specific chemical identity of a 
substance as a trade secret, pursuant to EPCRA section 322 (42 U.S.C. 
11042). Regulations codifying the trade secret provisions can be found 
at 40 CFR part 350. Under the rule, all facilities reporting to TRI on 
lead and lead compounds would have to use the EPA Toxic Chemical 
Release Inventory Form R (EPA Form No. 9350-1). OMB has approved the 
existing reporting and recordkeeping requirements related to Form R, 
supplier notification, and petitions under OMB Control No. 2070-0093 
(EPA ICR No. 1363).
    For Form R, EPA estimates the industry reporting burden for 
collecting this information (including recordkeeping) to average 74 
hours per report in the first year (based on typical unit burden 
estimates for Form R completion and recordkeeping/mailing 
requirements), at an estimated cost of $5,079 per Form R. In subsequent 
years, the burden is estimated to average 52.1 hours per report, at an 
estimated cost of $3,557 per Form R. These estimates include the time 
needed to review instructions; search existing data sources; gather and 
maintain the data needed; complete and review the collection of 
information; and transmit or otherwise disclose the information. The 
actual burden on any specific facility may be different from this 
estimate depending on the complexity of the facility's operations and 
the profile of the releases at the facility.
    This rule is estimated to result in additional reports from 
approximately 9,800 respondents. Of these, approximately 3,600 
facilities are estimated to be reporting to TRI for the first time as a 
result of the rule, while the remainder are currently reporting 
facilities that will be submitting additional reports. The 9,800 
respondents will each submit an additional Form R. This rule is 
estimated to result in a total burden of 1.2 million hours in the first 
year, and 0.6 million hours in subsequent years, at a total estimated 
industry cost of $80 million in the first year and $40 million in 
subsequent years. The existing ICR will be amended to add 790,000 
burden hours (annual average burden for the first 3 years of ICR 
approval).
    Under the PRA, ``burden'' means the total time, effort, or 
financial resources expended by persons to generate, maintain, retain, 
or disclose or provide information to or for a Federal agency. This 
includes, where applicable, the time needed to review instructions; 
develop, acquire, install, and utilize technology and systems for the 
purposes of collecting, validating, and verifying information, 
processing and maintaining information, and disclosing and providing 
information; adjust the existing ways to comply with any previously 
applicable instructions and requirements; train personnel to be able to 
respond to a collection of information; search data sources; complete 
and review the collection of information; and transmit or otherwise 
disclose the information. EPA's burden estimates for the rule take into 
account all of the above elements, considering that under section 313, 
no additional measurement or monitoring may be imposed for purposes of 
reporting.
    A commenter asserts that EPA failed to meet Paperwork Reduction Act 
requirements because it has not provided Form R reporting instructions 
for the proposed changes to the TRI reporting requirements for lead and 
lead compounds. The commenter contends that the proposed rule requires 
significant changes in the information submitted by regulated industry 
sectors on the Form R. The commenter asserts that OMB's Information 
Collection Review Handbook requires that materials submitted for review 
under the Paperwork Reduction Act must be accompanied by the documents 
to be used in the collection of information (i.e., forms, schedules, 
questionnaires, handbook, manual, interview plan or guide, rule, 
regulation, or other document), and any other explanatory material to 
be given or sent to prospective respondents. The commenter asserts that 
the current Form R reporting instructions do not provide the guidance 
necessary for reporting lead and lead compounds at the lower reporting 
thresholds with elimination of exemptions such as the de minimis 
exemption and changed rules for reporting. The commenter asserts that 
EPA has not issued guidance regarding how to comply under the proposed 
lower reporting thresholds, indicated what its plans are for issuing 
such guidance, or allowed formal opportunity for stakeholders to review 
and comment.
    EPA disagrees with the commenter. EPA did not propose significant 
changes in the types of information to be reported by industry. EPA 
proposed using the existing Form R for reports that would be required 
under the lower reporting threshold. Since EPA did not propose to amend 
the Form R, and the existing Form R was already approved

[[Page 4546]]

by OMB, EPA was not required to submit the Form R separately with the 
ICR amendment at the proposed rule stage. Nevertheless, the proposed 
ICR amendment that EPA submitted to OMB included a copy of the existing 
ICR approved by OMB, along with a copy of the Form R. The existing ICR 
also specifically describes all of the existing reporting elements on 
Form R.
    EPA strongly disagrees with the suggestion that it has circumvented 
the notice and comment process. The preamble to the proposed rule, the 
economic analysis, and the proposed ICR amendment all specifically 
describe EPA's proposal to lower reporting thresholds, and to change 
the reporting requirements so as not to allow use of the de minimis 
exemption, range reporting or Form A for reports submitted under the 
lowered thresholds. The Federal Register provided public notice and 
specifically solicited public comments on the changes to reporting 
requirements and reporting instructions that were being considered, as 
well as on the Agency's associated burden estimates. The Agency 
provided a functional description of the changes in reporting that 
would result from his rule. Therefore, EPA was in compliance with the 
PRA and with OMB requirements.

D. What are the Determinations Under the Unfunded Mandates Reform Act 
and Executive Order 13084?

    Pursuant to Title II of the Unfunded Mandates Reform Act of 1995 
(UMRA) (Public Law 104-4), EPA has determined that this action does not 
contain a ``Federal mandate'' that may result in expenditures of $100 
million or more for the private sector in any 1 year, nor will it 
result in such expenditures for State, local, and tribal governments in 
the aggregate. The costs associated with this action are estimated in 
the economic analysis prepared for this final rule (Ref. 46), which is 
included in the public docket and summarized in Unit VII. of this 
preamble.
    EPA has determined that it is not required to develop a small 
government agency plan as specified by section 203 of UMRA or to 
conduct prior consultation with State, local, or tribal governments 
under section 204 of UMRA, because the rule will not significantly or 
uniquely affect small governments and does not contain a significant 
Federal intergovernmental mandate.
    Finally, EPA believes this rule complies with section 205(a) of 
UMRA. The objective of this rule is to expand the public benefits of 
the TRI program by exercising EPA's discretionary authority to lower 
reporting thresholds, thereby increasing the amount of information 
available to the public regarding the use, management, and disposition 
of listed toxic chemicals. In making additional information available 
through TRI, the Agency increases the utility of TRI data as an 
effective tool for empowering local communities, the public sector, 
industry, other agencies, and State and local governments to better 
evaluate risks to public health and the environment.
    As described in Unit VI. of this preamble, EPA considered burden in 
the threshold selection. The rule also contains reporting requirements 
that will limit burden (e.g., reporting limitations for lead in certain 
alloys). In addition, existing burden-reducing measures (e.g., the 
laboratory exemption, and the otherwise use exemptions, which include 
the routine janitorial or facility grounds maintenance exemption, motor 
vehicle maintenance exemption, structural component exemption, intake 
air and water exemption and the personal use exemption) will apply to 
the facilities that file new reports as a result of this rule. EPA also 
will be assisting small entities subject to the rule, by such means as 
providing meetings, training, and compliance guides in the future, 
which also will ease the burdens of compliance. Many steps have been 
and will be taken to further reduce the burden associated with this 
rule, and to EPA's knowledge there is no available alternative to the 
rule that would obtain the equivalent information in a less burdensome 
manner. For all of these reasons, EPA believes the rule complies with 
UMRA section 205(a).
    In addition, today's rule does not significantly or uniquely affect 
the communities of Indian tribal governments. Accordingly, the 
requirements of section 3(b) of Executive Order 13084, entitled 
Consultation and Coordination with Indian Tribal Governments (63 FR 
27655, May 19, 1998) do not apply to this rule.

E. What are the Determinations Under Executive Orders 12898 and 13045?

    Pursuant to Executive Order 12898, entitled Federal Actions to 
Address Environmental Justice in Minority Populations and Low-Income 
Populations (59 FR 7629, February 16, 1994), the Agency has considered 
environmental justice related issues with regard to the potential 
impacts of this action on environmental and health conditions in low-
income populations and minority populations.
    Since this is a significant regulatory action, additional OMB 
review is required under Executive Order 13045, entitled Protection of 
Children from Environmental Health Risks and Safety Risks (62 FR 19885, 
April 23, 1997). The Agency has, to the extent permitted by law and 
consistent with the agency's mission, identified and assessed the 
environmental health risks and safety risks that may disproportionately 
affect children.
    By lowering the section 313 reporting thresholds for lead and lead 
compounds, EPA is providing communities across the United States 
(including low-income populations and minority populations) with access 
to data that may assist them in lowering exposures and consequently 
reducing chemical risks for themselves and their children. This 
information can also be used by government agencies and others to 
identify potential problems, set priorities, and take appropriate steps 
to reduce any potential risks to human health and the environment. 
Therefore, the informational benefits of the rule are expected to have 
a positive impact on the human health and environmental impacts of 
minority populations, low-income populations, and children.

F. What is the Determination under Executive Order 13132?

    Executive Order 13132, entitled Federalism (64 FR 43255, August 10, 
1999), requires EPA to develop an accountable process to ensure 
``meaningful and timely input by State and local officials in the 
development of regulatory policies that have federalism implications.'' 
``Policies that have federalism implication'' is defined in the 
Executive Order to include regulations that have ``substantial direct 
effects on the States, on the relationship between the national 
government and the States, or on the distribution of power and 
responsibilities among the various levels of government.''
    Under section 6 of Executive Order 13132, EPA may not issue a 
regulation that has federalism implications, that imposes substantial 
direct compliance costs, and that is not required by statute, unless 
the Federal government provides the funds necessary to pay the direct 
compliance costs incurred by State and local governments, or EPA 
consults with State and local officials early in the process of 
developing the proposed regulation. EPA also may not issue a regulation 
that has federalism implications and that preempts State law, unless 
the Agency consults with State and local officials early in the process 
of developing the proposed regulation.

[[Page 4547]]

    This final rule does not have federalism implications. It will not 
have substantial direct effects on the States, on the relationship 
between the national government and the States, or on the distribution 
of power and responsibilities among the various levels of government, 
as specified in Executive Order 13132. This action is expected to have 
a limited impact on municipal governments that operate electric 
utilities that may be affected by this action. EPA estimates that there 
are only 13 publicly-owned electric utility facilities that are 
potentially affected by the rule. Of these 13 facilities, 8 are 
expected to file one additional report as a result of this action. 
Thus, the requirements of Section 6 of the Executive Order do not apply 
to this rule.

G. What are the Determinations under the National Technology Transfer 
and Advancement Act?

    Section 12(d) of the National Technology Transfer and Advancement 
Act of 1995 (NTTAA) (15 U.S.C. 272 note) directs EPA to use voluntary 
consensus standards in its regulatory activities unless doing so would 
be inconsistent with applicable law or impractical. Voluntary consensus 
standards are technical standards (e.g., materials specifications, test 
methods, sampling procedures, etc.) that are developed or adopted by 
voluntary consensus standards bodies. The NTTAA directs EPA to provide 
Congress, through OMB, explanations when the Agency decides not to use 
available and applicable voluntary consensus standards.
    This action does not involve technical standards, nor did EPA 
consider the use of any voluntary consensus standards. In general, 
EPCRA does not prescribe technical standards for threshold 
determinations or completion of EPCRA section 313 reports. EPCRA 
section 313(g)(2) states that ``In order to provide the information 
required under this section, the owner or operator of a facility may 
use readily available data (including monitoring data) collected 
pursuant to other provisions of law, or, where such data are not 
readily available, reasonable estimates of the amounts involved. 
Nothing in this section requires the monitoring or measurement of the 
quantities, concentration, or frequency of any toxic chemical released 
into the environment beyond that monitoring and measurement required 
under other provisions of law or regulation.''

H. What are the Requirements of the Congressional Review Act?

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

List of Subjects in 40 CFR Part 372

    Environmental protection, Community right-to-know, Reporting and 
recordkeeping requirements, and Toxic chemicals.

    Dated: January 8, 2001.
Carol M. Browner,
Administrator.
    Therefore, 40 CFR part 372 is amended as follows:

PART 372--[AMENDED]

    1. The authority citation for part 372 will continue to read as 
follows:

    Authority: 42 U.S.C. 11023 and 11048.


    2. In Sec. 372.28 by adding one chemical to paragraph (a)(1) 
alphabetically and to paragraph (a)(2) by alphabetically adding one 
category to read as follows:


Sec. 372.28  Lower thresholds for chemicals of special concern.

    (a) * * *
    (1) * * *

 
----------------------------------------------------------------------------------------------------------------
                         Chemical Name                                  CAS No.            Reporting Threshold
----------------------------------------------------------------------------------------------------------------
 
*                *                *                    *                *                        *
                                                            *
 Lead (this lower threshold does not apply to lead when                       7439-92-1                      100
 contained in a stainless steel, brass or bronze alloy)
 
*                *                *                    *                *                        *
                                                            *
----------------------------------------------------------------------------------------------------------------

    (2)       *       *       *

 
------------------------------------------------------------------------
                 Category Name                     Reporting Threshold
------------------------------------------------------------------------
 
*                *                *                    *
           *                        *                        *
 Lead Compounds                                                      100
 
*                *                *                    *
           *                        *                        *
------------------------------------------------------------------------

* * * * *
[FR Doc. 01-1045 Filed 1-16-01; 8:45 am]
BILLING CODE 6560-50-F


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