[Federal Register Volume 86, Number 113 (Tuesday, June 15, 2021)]
[Rules and Regulations]
[Pages 31622-31637]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2021-12327]


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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 261

[EPA-HQ-RCRA-2016-0040; FRL-10014-42-OLEM]


Corrosive Waste Rulemaking Petition; Denial

AGENCY: Environmental Protection Agency (EPA).

ACTION: Notice; final denial of rulemaking petition.

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SUMMARY: The Environmental Protection Agency (EPA or the Agency) is 
responding to a rulemaking petition (``the petition'') requesting 
revision of the Resource Conservation and Recovery Act (RCRA) 
corrosivity hazardous waste characteristic regulation. The petition 
requests that the Agency make two changes to the current corrosivity 
characteristic regulation: Revise the regulatory threshold for defining 
waste as corrosive from the current value of pH 12.5, to pH 11.5; and 
expand the scope of the RCRA corrosivity definition to include non-
aqueous wastes in addition to the aqueous wastes currently regulated. 
The Agency published a tentative denial of the rulemaking petition on 
April 11, 2016. Today the Agency is publishing a final denial of the 
rulemaking petition.

DATES: This final action is effective on June 15, 2021.

ADDRESSES: The EPA has established a docket for this action under 
Docket ID No. EPA-HQ-RCRA-2016-0040, at http://www.regulations.gov. All 
documents in the docket are listed on the http://www.regulations.gov 
website. Certain other material, such as copyrighted material, is not 
placed on the internet and will be publicly available only in hard copy 
form. Publicly available docket materials are available electronically 
through http://www.regulations.gov.

FOR FURTHER INFORMATION CONTACT: Gregory Helms, Materials Recovery and 
Waste Management Division, Office of Resource Conservation and 
Recovery, Office of Land and Emergency Response, (Mail Code 5304P), 
Environmental Protection Agency, 1200 Pennsylvania Ave. NW, Washington, 
DC 20460; telephone number: 703-308-8845; email address: 
[email protected]

SUPPLEMENTARY INFORMATION:

Table of Contents

I. Executive Summary
II. General Information
    A. Does this action apply to me?
    B. What action is EPA taking?
    C. What is EPA's authority for taking this action?
    D. What are the incremental costs and benefits of this action?
III. Background
    A. Who submitted the petition to the EPA and what do they seek?
    B. Who commented on the tentative denial of the petition?
IV. Public Comments Received and Agency Response
    A. Petitioner Comments

[[Page 31623]]

    1. The Petitioners Assert That the Agency Inadequately 
Considered the Available Information When it Promulgated the 
Existing RCRA Corrosive Hazardous Waste Definition in 1980
    2. The Petitioners Assert That the Agency Must Use the Globally 
Harmonized System for the Classification and Labeling of Chemicals 
(GHS) as the Basis for the RCRA Corrosivity Regulation
    3. The Petitioners Assert That the Agency Inadequately 
Considered Supporting Materials Submitted With the Petition, and 
Other Facts Cited by the Petition
    4. The Petitioners Assert That Concluding That WTC Exposures and 
Injuries Are a RCRA Damage Incident is Not Necessary To Support the 
Petition
    5. The Petitioners Assert That EPA Misunderstands the 
Applicability of RCRA Regulations to the WTC Dust and Debris
    6. The Petitioners Assert That the Agency Improperly Considered 
the Potential Impact of the Requested Corrosivity Characteristic 
Revisions
    7. Other Petitioner Comments
    B. Industry Stakeholder Comments
    C. Other Comments
V. EPA's Conclusions and Rationale for its Final Action Denying the 
PEER/Jenkins Rulemaking Petition To Revise the RCRA Corrosivity 
Hazardous Characteristic Regulation

I. Executive Summary

    This action finalizes the Agency's April 11, 2016 tentative denial 
of a rulemaking petition submitted by the group Public Employees for 
Environmental Responsibility (PEER) and Dr. Cate Jenkins, Ph.D. 
(``PEER/Jenkins Rulemaking petition''), on September 8, 2011, 
requesting that the Agency revise the corrosivity hazardous waste 
characteristic regulation promulgated under Subtitle C of the Resource 
Conservation and Recovery Act (RCRA). The petitioners sought two 
changes to the existing corrosivity characteristic regulation: (1) 
Revision of the pH regulatory value for defining a waste as corrosive 
hazardous waste from the current pH 12.5 or higher, to pH 11.5 or 
higher; and (2) expansion of the scope of the corrosivity regulation to 
apply to non-aqueous wastes in addition to the aqueous wastes addressed 
by the current regulation. The Agency published for public comment a 
tentative denial of the PEER/Jenkins Rulemaking petition on April 11, 
2016 (81 FR 21295), proposing to deny both requested revisions to the 
corrosivity characteristic regulation sought by the petitioners. In 
this Notice (and the Response to Comments document accompanying it), 
the EPA responds to the public comments received on the tentative 
denial and takes final action to deny the petition.

II. General Information

A. Does this action apply to me?

    As the Agency is not adding to or revising its regulations with 
today's Notice, no entities or wastes will be newly regulated or 
deregulated.

B. What action is EPA taking?

    Today the Agency is issuing a final response to the PEER/Jenkins 
rulemaking petition of September 8, 2011 that seeks revision to the 
RCRA corrosivity characteristic regulation for classifying waste as 
hazardous that would expand the scope of the regulation and subject 
additional waste to RCRA's cradle-to-grave waste management system. The 
Agency is denying the petition in its entirety.
    Under Subtitle C of RCRA, the EPA has developed regulations to 
identify solid wastes that must then be evaluated to determine whether 
they must also be classified as hazardous waste. Corrosivity is one of 
four waste characteristics that may cause the waste to be classified as 
``RCRA hazardous.'' The Agency defines which wastes are hazardous 
because of their corrosive properties at 40 CFR 261.22. On September 8, 
2011, the nongovernmental organization (NGO) PEER and Cate Jenkins, 
Ph.D., submitted a rulemaking petition to the EPA seeking changes to 
the current regulatory definition of corrosive hazardous wastes under 
RCRA. On April 11, 2016, the Agency published a Federal Register notice 
tentatively denying the rulemaking petition. In that notice of denial, 
the Agency provided its evaluation of the requested regulatory 
revisions, the materials submitted by the petitioners in support of the 
regulatory revisions being sought, and supplementary information 
collected by the Agency and identified as relevant to the issues raised 
by the petition. The 2016 tentative denial of the petition also 
solicited comments from the public on the issues raised by the petition 
and its supporting materials, the Agency's supplemental materials, 
materials submitted by a group representing industries that might be 
affected by any changes to the corrosivity regulation and the Agency's 
assessment of all these materials. Comments were initially to be 
accepted until June 10, 2016; however, the public comment period was 
extended by six months, closing on December 7, 2016, at the request of 
the petitioners.
    Today's Notice (and accompanying supporting material) responds to 
the comments received from the public on the tentative denial, and 
takes final action on the rulemaking petition, denying the petitioners' 
request to revise the RCRA corrosivity regulation. The reasons for the 
Agency's denial of the petition are described below in today's Notice.

C. What is EPA's authority for taking this action?

    The corrosivity hazardous waste characteristic regulation was 
promulgated under the authority of sections 1004 and 3001 of RCRA, as 
amended by the Hazardous and Solid Waste Amendments of 1984 (HSWA), 42 
U.S.C. 6903 and 6921. The Agency is responding to this petition for 
rulemaking pursuant to 42 U.S.C. 6903, 6921 and 6974, and implementing 
regulations 40 CFR parts 260 and 261.

D. What are the incremental costs and benefits of this action?

    There are neither costs nor benefits resulting from this final 
action, as the Agency is not promulgating any regulatory changes.

III. Background

A. Who submitted the petition to the EPA and what do they seek?

    On September 8, 2011, petitioners PEER and Cate Jenkins, Ph.D., 
submitted to the EPA a rulemaking petition seeking revisions to the 
RCRA hazardous waste corrosivity characteristic definition (see 40 CFR 
261.22(a)(1)).\1\ On September 9, 2014, the petitioners filed a 
petition for Writ of Mandamus, arguing that the Agency had unduly 
delayed in responding to the 2011 petition, and asking the Court \2\ to 
compel the Agency to respond to the petition within 90 days. The Court 
granted the parties' joint request for a stay of all proceedings until 
March 31, 2016. Following publication of the tentative denial of the 
petition, the parties jointly petitioned the court to hold the case in 
abeyance until the Agency publishes in the Federal Register a final 
denial of the Petition for Rulemaking or an Advanced Notice of Proposed 
Rulemaking or a Proposed Rule. Under this agreement, the Agency is 
obligated to file status reports with the court at 120-day intervals. 
The latest

[[Page 31624]]

such report was filed with the court on April 5, 2021.
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    \1\ Sec.  261.22(a)(1) identifies an aqueous solid waste as a 
corrosive hazardous waste if a representative sample exhibits a pH 
less than or equal to 2, or greater than or equal to 12.5.when 
tested with a pH meter using EPA Method 9040C, published in the 
Agency Hazardous waste test method Compendium, SW-846. https://www.epa.gov/hw-sw846/sw-846-compendium.
    \2\ The Petitioners' lawsuit was filed with the U.S. Court of 
Appeals for the District of Colombia Circuit. https://www.cadc.uscourts.gov/internet/home.nsf.
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    The petition sought two specific changes to the 40 CFR 261.22(a)(1) 
definition of a corrosive hazardous waste:
    1. Reduction of the pH regulatory value for defining alkaline 
corrosive hazardous wastes from the current standard of pH 12.5 or 
higher to pH 11.5 or higher; and
    2. Expansion of the scope of the RCRA hazardous waste corrosivity 
definition to include non-aqueous wastes, as well as currently 
regulated aqueous wastes.
    The Agency published for public comment a tentative denial of this 
RCRA rulemaking petition on April 11, 2016, in accordance with 40 CFR 
260.20(c) and (e). The public comment period for the tentative denial 
was originally scheduled to close on June 10, 2016, but was extended 
until December 7, 2016, at the request of the petitioners. The Agency 
received 29 comments on the tentative denial (including requests for a 
comment period extension), and is today responding to those comments, 
and taking final action to deny all parts of the petition.

B. Who commented on the tentative denial of the petition?

    Commenters include the petitioners, a number of groups representing 
different sectors of industry, health research groups studying persons 
exposed to the World Trade Center (WTC) collapse, the state of Michigan 
Department of Environmental Quality (DEQ), national and state groups 
representing municipal wastewater treatment facility owners/operators 
(also known as publicly owned treatment works, or POTWs), and several 
private citizens. The public comments on the Agency's tentative denial 
of the PEER/Jenkins Rulemaking petition can be found by searching at: 
http://www.Regulations.gov, using Docket ID Number EPA-HQ-RCRA-2016-
0040.
    In a separate action, on April 13, 2017 (82 FR 17793), EPA opened a 
public comment period to solicit public comment on virtually any 
existing EPA regulation, to implement Executive Order 13777 on 
regulatory reform (See: http://www.Regulations.gov, Docket ID Number 
EPA-HQ-OA-2017-0190). The Agency requested that the public identify 
regulations they believed to be in need of revision, including 
regulations commenters believed to be outdated, unnecessary, 
ineffective or unduly burdensome. Eight of the more than 400,000 
comments received by the docket addressed the PEER/Jenkins Rulemaking 
petition and the Agency's initial response presented in the tentative 
denial. Seven of the comments were from particular industries or 
industry trade groups or organizations, and one was from the State of 
Oklahoma Department of Environmental Quality (DEQ). EPA considered all 
the comments received, on both the tentative denial and the eight 
comments received on the PEER/Jenkins Rulemaking petition through the 
implementation of Executive Order 13777. The petitioners' comments and 
those of several individuals opposed the Agency's tentative denial. 
Industry commenters generally supported it, as did the Michigan DEQ, 
organizations representing publicly owned treatment works (POTWs, which 
are municipal wastewater treatment facilities), and several private 
citizens. The Oklahoma DEQ supported regulation of non-aqueous wastes 
that may be corrosive. While two WTC-survivor health research groups 
commented in support of requests to extend the public comment period 
for the tentative denial, neither of these groups submitted substantive 
comments.

IV. Public Comments Received and Agency Response

A. Petitioner Comments

    Petitioners PEER and Dr. Jenkins submitted extensive comments 
addressing most aspects of the tentative denial. Today's Notice 
addresses comments the Agency believes present the petitioners' key 
arguments and supporting information advocating for their requested 
revisions to the corrosivity regulations. The Agency responds to more 
detailed petitioner comments in the Response to Comments document 
accompanying today's Notice, which is available in the public docket 
for this action. While the PEER/Jenkins comments are wide-ranging, they 
can be summarized as raising the following major objections to the 
tentative denial and its conclusions:
     The petitioners assert that the original corrosivity 
regulation did not appropriately consider the information available at 
the time the regulation was developed (i.e., 1980).
     The petitioners assert that the Agency has a legal 
obligation to implement the Globally Harmonized System for the 
Classification and Labeling of Chemicals (GHS) criteria as the RCRA 
corrosivity regulation.
     The petitioners assert that the Agency inadequately 
considered information submitted by petitioners in support of the 
petition.
     The petitioners assert that many of the injuries to World 
Trade Center (WTC) disaster first responders and others were caused by 
the corrosive nature of the dust generated by the collapse of the 
towers,\3\ and that a revised RCRA corrosivity regulation definition 
can prevent such injuries should similar exposures occur in the future.
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    \3\ The term ``corrosivity'' is used extensively in discussions 
of this issue by both the petitioners and by the Agency. However, 
the Agency believes petitioners and the Agency each intend different 
meanings when using the term. The petitioners apply the term 
``corrosivity'' to a broad range of possible impacts to human 
health, for example over a pH range of 9.76-11.5, as described at 
page 53 of the May 6, 2007 petition support document. When the 
Agency uses the term ``corrosivity'' in the context of impacts to 
exposed humans, it is referring to potentially severe injuries, such 
as dissolving of skin proteins, chemically combining with cutaneous 
fats, and severe damage to keratin, as described in the 1980 
Background Document supporting the original corrosivity regulation 
and in the TD (see 81 FR 21297-21299, April 11, 2016). While today's 
Notice focuses on potential adverse effects on humans (as this is 
the petitioners' focus), the Agency was also concerned about the 
potential of corrosive wastes to damage storage containers, 
resulting in releases, mobilization of co-disposed acid or base-
soluble wastes, and potential to adversely affect aquatic life when 
developing the corrosivity characteristic in 1980. This concern was 
largely addressed by part 261.22(a)(2).
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     The petitioners assert that the EPA misunderstands the 
applicability of RCRA regulations to the WTC dust and debris.
     The petitioners assert that the Agency impermissibly 
considered information on the possible economic impacts of revising the 
corrosivity regulation submitted by industry stakeholders and their 
representatives, and that the conclusions in the tentative denial are 
largely based on industry impact estimates.
    The discussion below describes the petitioners' comments on the 
tentative denial in more detail and provides the Agency's response to 
those comments.
1. The Petitioners Assert That the Agency Inadequately Considered the 
Available Information When it Promulgated the Existing RCRA Corrosive 
Hazardous Waste Definition in 1980
    As in the petition, the petitioners argue in their comments on the 
tentative denial that the original regulation did not appropriately 
consider the information available in 1980, and that this represents an 
error. Petitioners believe that in relying on the 1972 International 
Labor Organization (ILO) guidance, the Agency should have directly 
promulgated the ILO guidance values as the corrosivity regulation and 
should not have considered additional information in establishing the 
regulation. The ILO guidance, as well as GHS guidance (discussed 
below), is intended to represent the inherent, or

[[Page 31625]]

intrinsic hazards that may be posed by direct contact with materials, 
with no controls on or mitigation of exposure. However, RCRA directs 
the Agency to regulate hazards as they occur in waste (when plausibly 
mismanaged) in most cases, and the Agency regulated potentially 
corrosive wastes under RCRA section 1004(5)(B) (42 U.S.C. 6903(5)(B)), 
as has been done for most wastes regulated as RCRA hazardous.\4\ RCRA's 
prohibition on the open dumping of wastes (42 U.S.C. 6903(14)), and 
requirements for solid waste disposal and management (42 U.S.C. 
6944(a), (b)) means that all waste is intended to receive some level of 
management (under either federal or state laws and regulations), with 
some exceptions.\5\ Regulations at 40 CFR parts 240-258 (particularly 
parts 257 and 258) describe the minimum management requirements for 
wastes, regardless of the hazards they may (or may not) pose. Wastes 
found to potentially pose significant or substantial hazards when 
managed at this minimal level of control require more stringent 
management. Such wastes warrant classification as hazardous (under 42 
U.S.C. 6903(5)(B), through the listings and hazardous characteristics 
regulations) and control under the more stringent and detailed 
provisions of RCRA Subtitle C and the regulations developed under its 
authority. The Agency reserved RCRA section 1004(5)(A) for wastes that 
pose a significant hazard regardless of how they are managed. 
Therefore, the Agency appropriately relied on information in addition 
to the ILO guidance when developing the RCRA corrosivity 
characteristic, as described in the 1978 proposed rule, the 1980 final 
rulemaking and its supporting Background Document (EPA 1980), when it 
published the tentative denial of the petition (81 FR 2199-21302, April 
11, 2016),\6\ and in issuing today's final Notice and supporting 
information.
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    \4\ Consideration of corrosivity hazards under plausible 
mismanagement conditions is part of the basic program structure 
developed by the Agency in 1980 for implementing RCRA. The Agency 
described its approach to implementing RCRA's hazardous waste 
classification requirements in the rulemakings that promulgated the 
bulk of the RCRA regulatory program in 1980. In proposing its 
approach to developing hazardous waste characteristics regulations, 
the Agency proposed three criteria, the second of which was ``. . . 
that the likelihood of a hazard developing if the waste is 
mismanaged is sufficiently great. . . .''. The Agency continued this 
discussion by noting that ``EPA distilled the common features of 
hazardous waste--when improperly disposed of--into the following 
groups of candidate characteristics: . . . . 2. Corrosivity. . . .'' 
This discussion references the language of RCRA section 1004(5)(B) 
as the basis for the hazardous characteristics regulations, 
including corrosivity. (43 FR 58950, December 18, 1978) The Agency 
clarified the role of RCRA section 1004(5)(A) in implementing RCRA 
in the rulemaking promulgating most of the RCRA regulatory program. 
In considering how to structure and use hazardous waste listings, 
the Agency identified criteria for two categories of listed waste: 
Acutely hazardous waste and toxic waste. RCRA section 1004(5)(A) is 
referenced in the Agency's description of acutely hazardous waste, 
noting that these wastes are so dangerous that they meet the 
statutory definition ``. . . regardless of how they are managed. It 
is EPA's conviction that most wastes are hazardous only because they 
``pose a substantial . . . hazard . . . when improperly managed'' 
and thus meet RCRA section 1004(5)(B). The discussion goes on to 
note that acutely hazardous waste ``. . . include those which have 
been shown to be fatal to humans at low doses . . .'' but notes that 
waste explosives would also meet the Part (A) definition. EPA used 
these criteria to identify a list of high concentration waste 
commercial chemical products identified as acutely hazardous at 40 
CFR 261.33 (45 FR 33106, May 19, 1980). Also see 40 CFR 261.10, 
261.11(a)(2) and 261.11(a)(3).
    The Agency identified one report of an LD50 value 
below the acute hazard criteria, for sodium hydroxide (acute hazard 
criteria LD50=50 mg/kg-bw or lower; NaOH reported LC50=44 mg/kg-bw, 
in rats). While this report may indicate that sodium hydroxide could 
be added to the ``P-list'' of hazardous wastes, it does not imply 
that potentially corrosive wastes considered broadly may pose acute 
toxic hazards (see: 40 CFR 261.33, and NIOSH 2015, as reported by 
PubChem/NLM; downloaded March 20, 2019).
    \5\ 40 CFR part 257.1 describes the scope of the solid waste 
management regulations. This part identifies exceptions from the 
general requirements for some wastes that are otherwise regulated 
(e.g., under section 402 of the Clean Water Act, or under 40 CFR 
part 503), or for some materials which may not be waste when 
appropriately reused.
    \6\ The Agency has also considered factors in addition to 
inherent hazard in regulating many other wastes. For example, in 
developing the toxicity characteristic (TC) regulation (40 CFR 
261.24), the Agency explicitly incorporated a measure of the 
leaching release potential of toxic constituents in waste (the 
Toxicity Characteristic Leaching Procedure test) and also estimates 
of the likely dilution and attenuation of hazardous constituent 
concentrations that may occur during groundwater transport from a 
disposal site to a down-gradient drinking water well that could be a 
point of human exposure (see: 55 FR 11798, March 29, 1990).
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    When developing the current corrosivity regulation, the Agency 
proposed a value of pH 12.0 or higher to define hazardous corrosive 
waste (for aqueous wastes; 43 FR 58951-952, December 18, 1978). In 
consideration of public comments on the proposal, EPA established a 
final regulatory value of pH 12.5 or higher (and pH 2.0 or lower) to 
define aqueous corrosive hazardous waste (45 FR 33109, May 19, 1980). A 
consideration of the Agency in establishing the final regulation was 
the use of lime for treatment of municipal wastewater treatment 
sludges, as discussed in the Background Document (EPA 1980, pp 13-16). 
Such sludges contain a variety of organic chemicals, inorganic 
chemicals, and microbial contamination. Lime has been used for many 
years as a sludge treatment, particularly for the inactivation of 
microbial pathogens in the sludge. Such pathogens are effectively 
inactivated when the pH of the sludge is raised to pH 12 or higher, for 
a minimum of two hours and maintained at pH levels above 11.5 for an 
additional 22 hours (EPA 1981; EPA 1989; NRC 1996; Krach et al. 2008; 
and the National Lime Association, at: https://www.lime.org/lime-basics/uses-of-lime/enviromental/biosolids-and-sludge/). Treatment with 
lime can also provide control of odors that may be associated with more 
active biological pathogens. Lime continues to be used for biosolids 
``conditioning'', which allows this material to be more safely used as 
an agricultural fertilizer, and also to be more safely disposed in a 
municipal or other landfill when not used as a fertilizer. Therefore, 
the proposal to revise the corrosivity regulatory value to 11.5 could 
have a significant impact on the implementation of available treatments 
and management options for municipal wastewater treatment sludges.
    The petition and petitioner comments on the tentative denial argue 
that consideration of the value of using lime in waste treatment in 
setting the 1980 regulatory standard was improper at the time. However, 
considering the corrosive potential of wastes treated to high pH using 
materials like lime, with its widespread use for effective POTW sludge 
pathogen inactivation and stabilization was and remains an appropriate 
balancing of different waste management risks by the Agency. As the 
Agency noted in the tentative denial, no challenge to the 1980 
regulation was filed, and the time period to challenge that rule has 
long passed under the judicial review provision of RCRA section 7006, 
which requires such challenges to be filed within 90 days of the rule's 
promulgation. The opportunity to petition the Agency for changes to any 
RCRA rule is always available to members of the public (as in the 
current case), but such petitions are evaluated typically based on new 
information identified by petitioners (as well as information 
identified by the Agency, and those commenting on a proposed Agency 
action) as the basis for the requested changes to a regulation.
    Petitioners also argue that the current pH 12.5 corrosivity 
regulatory value is no longer necessary to allow reuse of biosolids due 
to other changes in the RCRA regulatory program, such as RCRA deference 
to the Clean Water Act (CWA) programs promulgated at 40 CFR part 503 
addressing biosolids use as agricultural fertilizer. However, biosolids 
that are RCRA hazardous cannot be land applied as fertilizer

[[Page 31626]]

under the Part 503 program.\7\ If the corrosivity regulatory pH was 
changed to pH 11.5 as petitioners request, lime stabilized biosolids 
(typically having a pH of 12.0 or higher) would be considered RCRA 
hazardous and ineligible for the Part 503 program. As hazardous waste, 
stabilized biosolids would be treated to reduce their pH to below 11.5, 
so they would no longer be hazardous waste (``decharacterization'' 
treatment and treatment for underlying hazardous constituents, which 
would be required by the RCRA land disposal restrictions (LDR) 
regulations; 40 CFR 268.40). Stockpiled biosolids with lowered pHs show 
increases in biological activity (EPA 1981), resulting in the 
development of strong odors.
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    \7\ 40 CFR 503.6 (e) on hazardous sewage sludge states that the 
regulations do not apply to sewage sludge that is hazardous waste. 
Therefore, pH 12 sludge classified as corrosive hazardous waste 
(under the petitioners' proposals) would be ineligible for land 
application under the Part 503 program.
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2. The Petitioners Assert That the Agency Must Use the Globally 
Harmonized System for the Classification and Labeling of Chemicals 
(GHS) as the Basis for the RCRA Corrosivity Regulation
    In the petition, and in comments on the Agency's tentative denial, 
the petitioners argue that the Agency should promulgate the guidance on 
corrosivity adopted by GHS as the RCRA corrosivity regulation, and 
further argues that the Agency has a legal obligation to do so. As 
described in greater detail in the tentative denial (81 FR 21300-21302, 
April 11, 2016), GHS is a technical guidance document developed by 
coordination among several organizations of the United Nations (U.N.), 
with the participation of many U.N. member nations, including the U.S., 
and other stakeholders.\8\ The goal of GHS was to create a single 
hazard evaluation and labeling/communication system that could be a 
global reference for chemicals and chemical products in transport, in 
the workplace and in commerce generally (GHS, Forward, paragraph 2). 
GHS is based on U.N.-sponsored technical guidance on the safe transport 
and handling of dangerous goods as well as on national and 
international systems for identifying chemical hazards in the 
workplace.
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    \8\ GHS was first published in 2003 and has been periodically 
revised; it is currently in its eighth revision, published in 2019. 
See: https://www.unece.org/trans/danger/publi/ghs/ghs_welcome_e.html.
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    The petitioners argue that the Agency has a legal obligation to 
implement the GHS criteria on corrosivity/irritancy as the RCRA 
corrosivity regulation.\9\ However, they acknowledge that adoption or 
reliance on GHS in regulations is voluntary:
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    \9\ In arguing that the EPA must adopt the GHS corrosivity 
criteria as the RCRA corrosivity definition, petitioners also over-
simplify GHS. In the petitioners' view, ``adopting GHS'' in the 
current context means establishing pH 11.5 as the corrosivity 
regulatory value. In fact, the GHS corrosivity criteria (GHS Chapter 
3.2) also rely on human exposure data, animal test results, and in 
vitro test results as preferred data sources, and reliance on pH 
11.5 only if other data are not available.

Although the GHS standard is voluntary for U.N. member nations, the 
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United States has chosen to adopt it. (page 54, petitioner comments)

    In support of their statement that the United States has chosen to 
adopt GHS, petitioners reference a U.S. State Department website that 
encourages the adoption of GHS by federal regulatory agencies, and 
which notes that EPA participated in a GHS implementation committee 
managed by the State Department. However, the petitioners misunderstand 
the role and authority of this implementation committee. While seeking 
to facilitate adoption of GHS criteria in appropriate federal 
regulatory programs, the committee has no statutory authority to 
require that federal agencies adopt GHS in whole or in part in any of 
their regulatory programs. For example, while EPA has considered using 
GHS for product classification or labeling under FIFRA, it has not done 
so (https://www.epa.gov/pesticide-labels/pesticide-labels-and-ghs-comparison-and-samples; downloaded 03/02/20). The Consumer Product 
Safety Commission (CPSC) has also considered GHS but not incorporated 
it into its regulations (https://www.cpsc.gov/content/policy-of-the-us-consumer-product-safety-commission-on-the-globally-harmonized-system-of).
    The Department of Transportation (DOT) periodically updates its 
hazardous materials regulations (HMR) to ensure that they are 
``harmonized'' with a variety of international transportation safety 
standards, including GHS. ``Harmonizing'' regulations generally means 
that although two sets of standards may be somewhat different from one 
another, they are not inconsistent. DOT most recently updated its 
regulations on May 11, 2020, including revising its definition of 
corrosivity. DOT notes that its revised corrosivity regulation does not 
rely on pH extremes.\10\
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    \10\ DOT's most recent revision to its regulations was published 
May 11, 2020 (91 FR 27810) in which DOT focuses first on consistency 
with the U.N. Transport of Dangerous Goods guidance. In modifying 
its regulation defining corrosivity, DOT specifically noted that its 
regulation does not rely on pH extremes to define corrosivity, a 
somewhat different approach than GHS takes (See 91 FR 27830, May 11, 
2020).
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    Only one federal agency, the Occupational Safety and Health 
Administration (OSHA), has chosen to revise its regulations to 
implement a modified version of GHS, for its hazard communication 
standard (HCS), under the authority of the Occupational Safety and 
Health Act of 1970 (77 FR 17574, March 26, 2012).\11\ Two EPA programs 
focused on regulation of chemicals reference or rely on the OSHA HCS 
regulations. The Emergency Planning and Community Right-to-Know Act 
(EPCRA) emergency response program regulations require facilities to 
provide state and local emergency responders with chemical hazard 
information using OSHA/HCS-required safety data sheets (SDS) for 
chemicals they have on-site, and the EPCRA regulations have been 
updated to be consistent with the new OSHA requirements (See: 81 FR 
38104, June 13, 2016). Under the Toxic Substances Control Act (TSCA), 
regulations for significant new uses of chemicals require a written 
hazard communications program to provide information to workers that 
may handle chemicals that are part of this program. Employers may rely 
on existing hazard communication programs established under the OSHA 
HCS regulations to show compliance with the TSCA program requirements. 
The Agency has proposed regulatory revisions to harmonize these EPA 
program requirements with the revised OSHA HC (81 FR 49598, July 28, 
2016).
---------------------------------------------------------------------------

    \11\ The UNECE GHS implementation tracking website provides 
progress for all countries. For the U.S., the latest reported 
activity by the EPA dates to 2007, and the latest reported GHS 
activity for CPSC is for 2008. (https://www.unece.org/trans/danger/publi/ghs/implementation_e.html#c25877). The U.S. government has 
also not adopted GHS criteria as the basis for waste managment 
controls at U.S. military bases in foreign countries. For example, 
there is no reference to GHS in the 2018 ``Japan Final Governing 
Standards'' at: https://www.usfj.mil/Portals/80/2018%20JEGS.PDF?ver=2018-04-26-195301-487.
---------------------------------------------------------------------------

    While the UN aspires to make GHS a globally implemented system for 
evaluating and classifying the hazards posed by chemicals and chemical 
products, guidance such as GHS only has the force of law in the United 
States if adopted and implemented as a requirement (or regulation) 
under the authority of specific laws (See GHS sections 1.1.2.6, 1.1.3). 
As guidance, GHS may be used by federal agencies on a voluntary basis, 
consistent with their enabling statutes. The Agency did review and 
consider the GHS corrosivity criteria and their underlying basis in

[[Page 31627]]

responding to the rulemaking petition. However, the Agency's conclusion 
was that direct use of the GHS criteria as a corrosivity regulatory 
standard was not appropriate as the GHS criteria are intended to 
identify the inherent or intrinsic hazards of chemicals or chemical 
products (which are usually associated with direct exposure to 
chemicals), and do not consider how exposures in different settings, 
such as waste management scenarios of concern under RCRA, might reduce 
the actual hazard posed. GHS is also a flexible classification system, 
and a pH-based hazard determination can be rebutted and changed by 
other test data, whereas RCRA hazardous characteristic determinations 
are not rebuttable (the criteria are codified in regulations that can 
only be changed through subsequent notice and comment rulemakings, and 
there is no delisting program for wastes that exhibit a hazardous 
characteristic).
    The petition and petitioner comments on the tentative denial raised 
similar issues concerning guidance on corrosivity by the ILO and the 
Basel Convention on Control of Transboundary Movements of Hazardous 
Wastes and Their Disposal (Basel Convention, or Basel). As described in 
the tentative denial and the background document supporting the 
existing corrosivity characteristic regulation (EPA, 1980), the Agency 
relied in part on the 1972 ILO guidance on corrosivity, and also 
considered other factors related to waste management in establishing 
the corrosivity regulation. While petitioners believe the ILO guidance 
should be the only basis for the RCRA corrosivity definition (i.e., 
that the Agency should directly promulgate the ILO recommended value as 
the RCRA corrosivity regulation), consideration of waste management 
factors is appropriate and within the Agency's discretion in 
establishing elements of national waste regulatory programs (RCRA 
section 1004(5)(B); 42 U.S.C. 6903(5)(B)).]
    The Basel Convention also addresses the potential corrosivity of 
wastes, as described in the tentative denial. Petitioners asserted in 
the petition and in their response to the tentative denial that the 
Agency is obligated to adopt the Basel Convention corrosivity 
definition. However, Annex III of Basel relies on a narrative 
definition for identifying corrosive wastes, rather than directly 
relying on pH, as the petitioners suggest the U.S should do. Further, 
the United States is not a party to the Basel Convention, and so has 
not obligated itself to implement Basel Convention requirements. Even 
if the U.S. were a party to the Basel Convention, the legally binding 
aspects of Basel are focused on transboundary movements of waste (i.e., 
imports and exports), through a system of notice and consent for such 
shipments between governments. The Basel hazardous waste criteria apply 
only to such imports and exports of waste, and nations that are Basel 
Parties are not obligated to (but may, at their discretion) use the 
Basel criteria in their domestic waste management programs.
    Having determined that reliance on GHS criteria in establishing 
regulatory requirements is voluntary (consistent with enabling 
statutes), the Agency turns to the question about whether or how GHS 
might be an appropriate basis for regulations under RCRA. The basis for 
GHS criteria is identified as ``the intrinsic hazard'' of chemicals, 
and implies direct exposure. GHS determinations of intrinsic hazard do 
not consider possible material handling procedures that might mitigate 
risks or the potential for waste or contaminant release, transport and 
exposure. RCRA provides authority to regulate waste either due to its 
intrinsic hazard (where such hazards are of a severe and acute nature), 
or when a waste poses risk as a result of mismanagement. However, EPA's 
approach is in most cases to regulate wastes posing risks when 
plausibly mismanaged, particularly where a waste does not exhibit 
acutely and highly toxic or other extremely hazardous properties (see 
Footnote 6 and 45 FR 33105-33109, May 19, 1980). This means that as a 
practical matter, under RCRA most hazards are identified and risk is 
evaluated in the context of waste management conditions and practices. 
This was the reasoning the Agency used in 1980 when it considered both 
the use of lime for POTW sludge stabilization \12\ and other waste 
treatment uses of lime, as well as the 1972 ILO guidance values, in 
establishing the current RCRA corrosivity regulatory value. In urging 
the adoption of GHS criteria as the basis for the corrosivity 
regulation, the petitioners are making the same argument as discussed 
elsewhere in today's Notice and in the response to comments document: 
That the Agency should base the corrosivity regulation solely on 
assessment of the intrinsic hazards potentially corrosive wastes may 
pose. The Agency has instead determined that it is appropriate to make 
waste management considerations part of the basis for the corrosivity 
hazardous waste definition.
---------------------------------------------------------------------------

    \12\ Lime continues to be used in treating POTW sludge (also 
known as biosolids) as well as in treatment of other wastes. Lime is 
used to increase the pH of biosolids (usually to pH 12) to control 
bacterial growth and odors. (See: EPA, 1981, NRC 1996; Krach e.al., 
2008; The Lime Association, 2018).
---------------------------------------------------------------------------

3. The Petitioners Assert That the Agency Inadequately Considered 
Supporting Materials Submitted With the Petition, and Other Facts Cited 
by the Petition
    Petitioner comments on the tentative denial argue at length (pp. 1-
18) that the Agency focused too narrowly in the tentative denial when 
considering the WTC disaster dust, cement kiln dust (CKD), and building 
demolition dust as examples of potentially corrosive dust that warrant 
regulation. Petitioners believe the Agency inadequately considered 
additional facts presented in the petition, and particularly 
information in the supporting materials submitted with the petition, 
and in so doing, violated its obligations under the Administrative 
Procedure Act to consider and respond to significant issues and facts 
brought to it during a rulemaking.
    The tentative denial focused on the WTC, CKD and building 
demolition dust discussions presented in the petition because the 
petition focused on these (See petition pp 28-36) in arguing for 
regulation of non-aqueous waste. The Agency did in fact review and 
consider the supporting material submitted with the petition as well as 
the petition itself and the relevant documents cited in petition 
footnotes (e.g., the Agency did not review the many news reports 
referenced in the petition, as there was no way to verify the 
information presented in them). The Agency also considered other 
information identified as relevant to the petition's proposals, and 
information submitted by other stakeholders. In doing so, the Agency 
concluded that aspects of the supporting material submitted were not 
relevant in responding to the petitioners' specific request to revise 
the corrosivity characteristic regulation, while other material was 
anecdotal or focused on illustrating the intrinsic hazards of some 
alkaline materials. However, as petitioner comments have redirected the 
Agency's attention to the petition's supporting materials (PEER 
comments pp 13-14), the Agency is presenting more detailed information 
on its examination and evaluation of those materials.
    The supporting materials sent to the Agency attached to the 
September 8, 2011, petition consist of two documents previously 
developed by petitioner Dr. Jenkins (one dated 2007 and the other

[[Page 31628]]

dated 2008), two pages from the 1972 ILO guidance document, and 
excerpts from several legal declarations and depositions. The two 
documents developed by Dr. Jenkins provide additional information on 
her views about the corrosivity of materials, among other issues. 
Different parts of these two documents were referenced in the petition 
related to arguments the petition was advancing. The Agency reviewed 
these two documents in their entirety in the course of developing the 
tentative denial of the petition and focused in particular on portions 
of the supporting documents referenced by the petition itself.\13\
---------------------------------------------------------------------------

    \13\ The petition also references numerous other sources of 
information in footnotes to the text, including research papers, 
government reports (and petitioner comments on a 2003 draft EPA 
Inspector General report), news reports and other material. EPA 
retrieved, reviewed and considered the most relevant of these and 
made them available to the public by placing them in the docket for 
the tentative denial.
---------------------------------------------------------------------------

    The first document, dated May 6, 2007, is a report addressed to 
members of the U.S. Senate and House of Representatives (i.e., 
Congress). It consists of two sections, plus 342 endnotes. As described 
by the document, Part 1 (pages 2-30) ``details the orchestrated 
falsifications by EPA, other governmental agencies and EPA funded 
scientists of pH data (actually changing the numbers) as well as their 
use of laboratory methods known to pre-neutralize samples before 
testing the pH of WTC dust.'' This part of the document criticizes the 
data collected on dust related to the WTC disaster by a number of 
research groups, including data and reports generated by the United 
States Geological Survey (USGS), researchers at Rutgers University, New 
York University (NYU), the Agency for Toxic Substances and Disease 
Registry (ATSDR), the EPA, the National Institute of Environmental 
Health Sciences (NIEHS), and the University of California, Davis. The 
scope of Dr. Jenkins' assertions of WTC dust sample mishandling, 
improper analysis, and incorrect health assessments are broad. In 
different portions of this discussion, the report describes data as 
being ``falsified'' (pp. 3, 6, 14, 17, 19), samples being improperly 
``pre-neutralized'' before pH testing (pp. 11, 12, 16), use of ``non-
optimal'' testing to give ``false'' test results (p.22), and asserted 
that researchers made false statements about the significance of test 
results (p. 23). The report goes on to identify the testing Dr. Jenkins 
believes would have been appropriate for the dust generated by the 
collapse of the WTC towers (pp 25-28). The report also states that EPA 
On-Scene Coordinators were on site on the day the towers were attacked 
and collapsed, and that regulations and guidance required them to do 
sampling to assess hazards, including pH testing.\14\ However, the 
Agency has been unable to identify such data; apparently such pH 
testing was not done, or if done, test results were not recorded or 
reported.
---------------------------------------------------------------------------

    \14\ Report Endnotes 125-129 reference EPA Region 6 training 
materials, and OSHA HAZWOPER regulations at 29 CFR 1910.120, 
Appendix E.
---------------------------------------------------------------------------

    Review of the studies about which Dr. Jenkins expressed concern 
shows that investigators were evaluating pH and many other properties 
of the collected dust samples.\15\ For example, Lioy (2002) tested for 
metals, asbestos, anions and cations, dioxins, brominated fire 
retardants, and the size and composition of different particulate 
fractions, in addition to pH. Plumlee et.al. (2006) evaluated settled 
dust samples collected outdoors (31 different locations) and indoors (2 
locations; all but one sample collected by USGS on September 17 and 18, 
2001), for metals, organic chemicals, pH, alkalinity and specific 
conductance. Two different leaching tests were done to understand the 
chemical reaction of dust with water (from acidic rainfall on September 
14, and ongoing street washing, dust control, or firefighting) and the 
potential for dust components to be absorbed by the throat and lungs of 
those exposed. In a study done by EPA scientists (EPA, 2002), dust 
samples were tested for physical properties and chemical composition, 
and were used in testing for the potential adverse effects of the dust 
on laboratory test animals.
---------------------------------------------------------------------------

    \15\ The pH of the vast majority of non-aqueous samples cannot 
be measured directly. Rather, most pH testing of solid samples 
involves adding some amount of water to the sample before testing it 
using a pH meter, as described in EPA Method 9040B. When testing 
only the pH of a solid sample of waste, water is often added in a 
1:1 ratio, as in EPA Method 9045C. One of Dr. Jenkins' concerns 
relates to the addition of water to WTC dust samples in ratios 
higher than one part water to one part waste (i.e., addition of more 
than one part water to WTC dust samples). However, most 
investigators were evaluating the dust for parameters and properties 
beyond pH and used dilutions they believed appropriate for the 
purposes of their study. To the degree that investigators fully 
describe the methods of testing and the amount of water added to WTC 
dust samples in the course of their research, it cannot be 
considered that they did anything improper; they simply were not 
using the testing approach Dr. Jenkins believes would have more 
directly responded to her concerns.
---------------------------------------------------------------------------

    Petitioners insist that pH of the whole dust was the key factor 
investigators should have known to focus on evaluating, and also insist 
that dust pH values were higher than reported (because investigators 
did not use the petitioners' preferred test method). These assertions 
disregard the fact that corrosive chemical burns were not identified 
among the reported injuries to first responders and others. They also 
disregard the variable composition and complexity of the dust and WTC 
worker exposures (which include building materials reduced to fine and 
coarse particulates, metals, a range of volatile and semivolatile 
organic chemicals and soot particulates from the ongoing fires) that 
investigators were trying to understand, as well as discounting the 
focus on public health concerns about exposure to fine, inhalable 
particulate matter \16\ and asbestos. Petitioner assertions about dust 
pH also fail to account for the effect of contact with water on the pH 
of dust (from water use for street washing, firefighting and dust 
suppression, as well as several rainfall events beginning September 
14), which would have moderated dust pH, so that as the dust changed, 
so did the alkalinity of exposures.\17\
---------------------------------------------------------------------------

    \16\ For information on inhalable particulates see: https://www.epa.gov/pm-pollution/particulate-matter-pm-basics.
    \17\ Mixing of water with atmospheric carbon dioxide forms 
carbonic acid, which when mixed with the dust would have reduced the 
pH of the dust. Therefore, the pH of dust to which workers were 
exposed would have declined over time starting as soon as the dust 
was exposed to water (USGS 2002, American Chemical Society 2019, 
Garrabrants et.al 2004). A major rainfall event occurred on 
September 14 (Cahill, 2004). Also, a report by the EPA-Inspector 
General (2003) described the successful use of continuous dust 
suppression by spraying water wherever dust was identified at the 
site, as well as wetting of the damaged building remains before 
their demolition (see pages 34-36). The last fires at the WTC site 
were extinguished in December 2001.
---------------------------------------------------------------------------

    Part 2 of the 2007 report Dr. Jenkins sent to the Congress (pages 
31-52) asserts that ``Long before 9/11/01--EPA falsifies the pH level 
causing chemical burns (irreversible tissue damage-).'' This part of 
the report describes the petitioners' concerns about the basis for the 
current corrosivity regulation. Much of the material in this section of 
the report was incorporated into the petition (see pp 6-24 of the 
petition) and the Agency reviewed and considered this material in 
developing the tentative denial. The issues raised by the petitioners 
in this discussion focus on their belief that the corrosivity 
characteristic regulations should consider only the inherent hazard of 
waste materials, and not consider the risks posed by possible exposure 
to materials when they are generated and managed as wastes. Petitioners 
believe consideration of any information in addition to assessments of 
intrinsic hazard resulted in a ``falsified'' corrosivity regulation. 
The Agency

[[Page 31629]]

believed in 1980, and continues to believe, that incorporation of waste 
management considerations is appropriate and within the Agency's 
discretion in establishing regulations under RCRA (RCRA section 
1004(5)(B); 42 U.S.C. 6903(5)(B)) including for the corrosivity 
characteristic.
    The second document, also developed by Dr. Jenkins (dated October 
13, 2008), is described as a supplement to the May 6, 2007 report sent 
to Congress, and was addressed to the Federal Bureau of Investigation 
(FBI). The first section of the report identifies statutes petitioners 
believe may have been violated by EPA's corrosivity characteristic 
regulation (see pp 2-9), based on their disagreement with the Agency's 
basis for establishing the regulation. The second section of the report 
is a recounting of historical incidents in which people were injured 
when directly and purposely exposed to lime (pp 10-17). The third 
section of the report is generally a reiteration of petitioner 
criticisms of the basis for the corrosivity characteristic regulation 
taken from the 2007 document. This section also criticizes the Agency's 
Report to Congress on Cement Kiln Dust (59 FR 709, January 6, 1994) and 
presents assertions regarding WTC dust evaluation. Much of the material 
is directly taken from the 2007 document (see pp 27-56), including 
repeating several of the graphs/tables/figures (see pp 11-24 of 2007 
report).
    The many examples of direct exposure to alkaline materials 
described in the 2008 document (to the FBI) reiterate the petitioners' 
view that the Agency should regulate corrosive materials based on 
assessments of the intrinsic or inherent hazards they may pose from 
direct exposure, rather than risks that might be posed in the course of 
waste management. As noted above, the approach advocated by the 
petitioners is used by GHS, where classification is intended to be 
based on the ``intrinsic hazard'' of chemicals, not on risk (although 
GHS does not rely on pH to define materials as corrosive if any other 
data are available; see GHS sections 1.1.2.6, 1.1.3.1, 3.2). Again, 
risks that might be posed in the course of waste management is an 
appropriate basis for the corrosivity regulation, and is within the 
Agency's discretion in implementing RCRA.
4. Petitioners Assert That Concluding That WTC Exposures and Injuries 
Are a RCRA Damage Incident Is Not Necessary To Support the Petition and 
Also Reiterate Their Assertion That WTC First Responder and Other 
Worker Injuries Are a Result of Exposure to Corrosive WTC Dust 
(Comments Pages 15, 105-124).\18\
---------------------------------------------------------------------------

    \18\ The possibility of exposures to asbestos used as 
fireproofing in parts of the WTC towers was an immediate and 
significant public health concern when the towers collapsed, and 
many studies of WTC dust and airborne materials focus on asbestos. 
However, as petitioners requested regulatory changes and materials 
submitted supporting this request do not focus on the presence of 
asbestos in air or dust samples, the Agency has not addressed 
asbestos issues in either the tentative denial or today's Notice.
---------------------------------------------------------------------------

    When the WTC towers collapsed after being attacked, an estimated 
one million tons of construction materials and the buildings' contents 
were pulverized into dust and debris, forming a dust cloud that 
distributed the dust over a 16-acre area of New York City. Destruction 
of the towers also resulted in numerous fires, which burned for several 
months after the collapse of the towers (Chemical & Engineering News, 
2003). The petition identified injuries to first responders and rescue 
and other workers resulting from inhalation exposure to airborne or 
settled WTC dust as a waste mismanagement damage incident that they 
believed supported the need to revise the RCRA corrosivity regulations. 
This assertion was one of the petitioners' main arguments supporting 
their request for changes to the corrosivity regulation definition. The 
Agency discussed this issue at length in its tentative denial of the 
rulemaking petition. (81 FR 21302-21305). Specifically, the Agency made 
two main arguments concerning petitioner assertions that the WTC dust 
caused corrosive injuries to first responders and other workers at the 
WTC site. These are: (1) Because of limitations of the available data 
(i.e., the complexity and variability of the dust composition and 
exposure levels), it is not possible to establish a causal connection 
between any potential corrosive properties of the dust and the injuries 
to those exposed; and (2) the injuries documented to have occurred in 
the WTC first responders and others exposed to potentially harmful 
dust, while serious, are not corrosive injuries as described in the 
1980 background document (EPA 1980) and which the Agency sought to 
prevent in promulgating the RCRA corrosivity regulation.
    While the petition asserted that the WTC exposures are a corrosive 
waste damage case, petitioner comments submitted in response to the 
tentative denial seem to be inconsistent as to the relevance of the WTC 
disaster and exposure of workers and others to the resulting dust. They 
assert that identification of WTC worker injuries as corrosive injuries 
is not a critical aspect of their argument supporting a change to the 
corrosivity regulations, but later in their comments reiterate 
arguments from the petition that WTC worker injuries are corrosive 
injuries.
    Petitioner comments first assert that it is ``[i]rrelevant whether 
WTC dust, caused corrosive injuries. . .'' because they believe that 
``[o]ther physical forms of corrosives . . . whether pH 11.5 and above 
or pH 12.5 and above have caused injuries'' (see page 15 of 
petitioners' comments). Petitioner comments then reference the 
materials submitted with and in support of the petition (i.e., the 
reports developed by Dr. Jenkins from 2007 and 2008 described above) as 
adequately supporting the petitioned changes to the corrosivity 
regulation, regardless of conclusions about the effects of WTC dust. 
Other parts of petitioner comments on the tentative denial repeat the 
petition's assertions that corrosive properties of the WTC dust caused 
the injuries (particularly respiratory injuries), reported by first 
responders and other workers subsequent to their work on the site (see, 
e.g., pp 108-118 of petitioners' comments). As petitioner comments 
reiterate their earlier assertions about the corrosive properties of 
the WTC dust, EPA is responding in today's Notice to those assertions, 
to make clear its conclusion that information concerning WTC dust and 
worker exposures and injuries cited by the petitioners does not support 
the petitioners' overall request.
    While the considerable amount of research on WTC worker health 
makes clear that injuries to WTC workers resulted from their exposure 
to the WTC dust,\19\ the existing data do not support attributing the 
injuries to possible corrosive properties of the dust. As described in 
the tentative denial, and elsewhere in today's Notice, it is not 
possible to establish a causal connection between the potential 
corrosive properties of the dust and the resultant injuries to those 
exposed for two reasons. First as described in the

[[Page 31630]]

tentative denial, WTC first responders, site workers, and others were 
exposed or potentially exposed, from 9/11/2001 until the clean-up 
concluded (January 2002), to a complex and changing ambient atmosphere 
that included many chemicals and particulate matter, as represented by 
evaluation of settled dust samples as well as ambient air test results, 
and which was unique to the WTC debris and dust.\20\ Attribution of the 
WTC first responder and worker injuries to a single cause or property 
of the WTC dust, such as its potential corrosivity, is confounded by 
the wide range and varying concentrations of numerous compounds found 
in air samples or settled WTC dust, and the changes in dust properties 
(particularly pH) over time.\21\ In one data set, the pH values 
reported for the outdoor dust ranged from pH 8.22 to 12.04 for samples 
collected at 33 locations at the WTC site on September 17 and 18, 2001 
(Plumlee, et al. 2006). In 22 of these samples there were measurable 
amounts of 39 different metals and inorganics, and up to 22.8% organic 
compounds. These samples also contained a range of particulates, 
including fine glass fibers and fine and coarse particulates to which 
workers were potentially exposed at different locations around the site 
at different times, as well as being exposed to the toxic metals and 
organics. The pH of the tested dust would have declined (become more 
neutral) over the several months workers were at the site, due to 
carbonation reactions of some dust constituents with water and 
atmospheric carbon dioxide (as well as the acidic nature of 
rainfall).\22\ In another study, test results for three samples of 
settled dust collected on September 16 and 17, 2001 showed pH values of 
9.2-11.5, and that 40% of the dust consisted of fine glass fibers, 9%-
20% was cellulose, and 37%-50% was non-fiber material including 
construction debris (concrete, gypsum) and inorganic and organic 
chemicals (Lioy, et.al. 2002).\23\ Several rainfall events starting on 
September 14 and through the first half of October, as well as use of 
water for firefighting and dust control at the site would have washed 
out many soluble inorganic constituents from the outdoor dust and also 
changed its pH (Lioy, 2002; Plumlee, 2006, and Cahill, 2004). A report 
by the 9/11 WTC Health Program \24\ presented an inventory of ``9/11 
Agents'' that were identified that may have posed hazards at the WTC 
site, the Pentagon crash site, or the Shanksville, PA crash site (WTC 
Health Program 2018; https://wwwn.cdc.gov/ResearchGateway/Content/pdfs/Development_of_the_Inventory_of_9-11_Agents_20180717.pdf). The 
inventory includes 352 chemicals or other materials (e.g., glass 
fibers, PM2.5). In addition, the 9/11 Agents inventory does 
not identify pH as a stressor, and while it does include some alkaline 
chemicals cited by petitioners as posing hazards (i.e., calcium 
hydroxide and calcium sulfate), it does not include calcium oxide, a 
compound petitioners repeatedly cite as a key compound of concern.\25\
---------------------------------------------------------------------------

    \19\ See data collected by NIH (https://disasterinfo.nlm.nih.gov/wtc-hazards), the City of New York 9/11 
Health index of studies (https://www1.nyc.gov/site/911health/researchers/wtc-scientific-bibliography.page), the September 3, 2011 
edition of The Lancet (Volume 378), and many other scientific 
journal publications (see Bibliography for the tentative denial and 
today's Notice).
    \20\ In many industrial settings, the same or very similar waste 
is generated on an ongoing or repeated basis because of the ongoing 
production of particular products. While waste varies, the wastes 
generated over time by a particular industrial process often have 
some consistency and are generated under conditions defined by the 
production process, making it easier to identify and assess hazards 
that may be posed by the waste. However, the WTC dust and debris 
were both unique to the events of 9/11/2001, had a complex and 
varying composition at different WTC locations and over time, and 
workers and others were exposed to it in a range of different 
settings, conditions, and time periods. Rainfall on 9/14/2001, and 
other days also altered the properties of the settled dust through 
carbonation reactions (reducing its pH), as did water used for 
firefighting and dust suppression. NYC rainfall in 2001 had an 
average pH of 4.4, which also contributed to neutralizing the dust 
(National Atmospheric Deposition Program, 2001). Workers were also 
exposed to smoke from the fires, the last of which was not 
extinguished until December of 2001. Further, there are not reliable 
records of where at the WTC site particular workers worked, the days 
they worked at different locations, their duration of work each day, 
and the composition of dust at those parts of the WTC site over 
time. These factors, in combination with the fact of incomplete 
exposure data make it impossible to identify causal relationships 
between particular exposures and adverse effects beyond the broad 
conclusion that many workers exposed to the dust and other 
pollutants present have experienced respiratory injuries and other 
adverse effects related to their exposure.
    \21\ Reviews of compiled data on compounds in the settled dust 
and/or air samples found up to 287 different chemicals or chemical 
groups (EPA 2003), or up to 352 different materials and chemicals 
(WTC Health Program 2018). Lioy (2006) identified a sequence of 4 
distinct exposure categories over time, each with somewhat different 
mixtures of pollutants, starting with collapse of the towers through 
December 29, 2001, plus one additional category for indoor 
exposures. They also identified the lack of an analysis of patterns 
of population exposure, and failure to test for airborne gases and 
coarse particulates in the first hours following collapse as 
significant data gaps that preclude quantitative exposure 
characterizations for most people.
    \22\ The National Atmospheric Deposition Program 2001 Annual 
Report identifies rainfall in the NYC area to have a pH of 
approximately 4.4. A pH of 7 is neutral, and values below 7.0 are 
acidic, while values above 7.0 are basic, or alkaline. Also, NOAA's 
``Records of Climatological Observations'' recorded rainfall of 1.9 
inches in NY Central Park on September 14, 2001, three days after 
the disaster. https://www.ncdc.noaa.gov/cdo-web/search. Accessed 
July 15, 2020.
    \23\ Also identified in the three samples were: 24 metals, seven 
pesticides, PCBs, 40 different PAHs, 82 semi-volatile organic 
compounds, 17 PCCDs and PCDFs, and 6 PBDE flame retardant chemicals.
    \24\ The 9/11 WTC Health Program is administered by CDC/NIOSH.
    \25\ The petition and petitioner comments on the Tentative 
Denial both reference calcium oxide as posing a significant hazard. 
While Portland cement powder contains calcium oxide, this compound 
is converted to calcium hydroxide and other calcium compounds in 
hardened concrete when water is mixed with the cement powder. The 
hydration reactions of cement powder give the resulting concrete its 
strength and hardness. (Northwestern U. website and U. Illinois 
website). Petitioners hypothesize the presence of calcium oxide in 
the WTC dust (see petition page 27), although studies of WTC dust 
fail to identify it as present, and petitioners identify no studies 
presenting data showing calcium oxide as present in WTC dust 
samples. Even if some calcium oxide was present in the dust when the 
towers collapsed, it would have combined with ambient water vapor 
(i.e., humidity) or water from rainfall, fire-fighting or dust 
suppression, and would be unlikely to be present in the dust for 
more than a day or two, if ever.
---------------------------------------------------------------------------

    The National Institute for Occupational Safety and Health \26\ 
(NIOSH) conducted ambient air and worker breathing zone monitoring for 
a range of possible air pollutants from September 18-October 4, 2001 
(CDC, 2002). Samples were collected in areas immediately adjacent to 
the debris pile, and for individuals actively involved in rescue 
efforts or working in the vicinity of the debris pile. These samples 
were found to contain measurable amounts of asbestos, carbon monoxide 
(CO), diesel exhaust, hydrogen sulfide (H2S), inorganic 
acids, mercury and other metals, polycyclic aromatic hydrocarbons 
(PAHs) and volatile hydrocarbons, and total and respirable 
particulates. Sulfuric acid was detected in 26 of 27 samples, with all 
levels less than the NIOSH recommended exposure level (REL) and OSHA 
permissible exposure level (PEL).\27\ Mercury and other metals were 
well below the relevant NIOSH and OSHA standards, with the exception of 
exposure of one worker using a cutting torch exposed to cadmium at 
levels exceeding the OSHA PEL. PAHs were found only at trace levels, 
and benzene was the only volatile organic found in 2 of 76 samples at 
levels exceeding the NIOSH REL, but below the OSHA PEL. For total 
particulates, values ranged from non-

[[Page 31631]]

detect to 2.3 mg/m\3\, with all samples below the NIOSH REL for 
Portland cement (10 mg/m\3\). Respirable particulates ranged up to 0.32 
mg/m\3\, well below the NIOSH REL for Portland cement (5 mg/m\3\). 
These data do not support petition assertions that both large and small 
airborne particulates would have posed corrosive hazards to exposed 
workers, as all these data show that WTC worker breathing zone 
concentrations of dust were substantially below both regulatory and 
health recommended concentration values for cement dust, which 
petitioners focus on as presenting the greatest hazards.
---------------------------------------------------------------------------

    \26\ NIOSH is part of the U.S. Centers for Disease Control and 
Prevention (CDC), in the U.S. Department of Health and Human 
Services. NIOSH is a research agency focused on the study of worker 
safety and health. Among other activities, NIOSH develops 
recommended exposure limits (RELs) for hazardous substances or 
conditions in the workplace (See NIOSH Pocket Guide to Chemical 
Hazards, at: https://www.cdc.gov/niosh/npg/default.html).
    \27\ OSHA is the Occupational Safety and Health Administration, 
which is part of the U.S. Department of Labor. Among other 
activities, OSHA develops regulations to establish permissible 
exposure levels (PELs) for worker exposure to airborne chemicals in 
the workplace (See: 29 CFR 1910.1000).
---------------------------------------------------------------------------

    Maslow et al. (2012) studied the health impacts of different 
exposures to local residents or individuals (n=785) who worked in 
buildings near the WTC site, but which were not severely damaged. They 
found dose-related pulmonary function decrements associated with acute 
exposure to the WTC dust (exposure on the day the buildings collapsed) 
and to chronic exposure (from indoor dust).\28\ Lower respiratory 
symptoms were evaluated using spirometry testing of forced expiratory 
volume and other measures, but no corrosive injuries were reported. A 
study of children enrolled in the WTC Health Registry initially found a 
significant increase in new asthma cases associated with exposure to 
the dust cloud on 9/11/2001 (Thomas, et al., 2008), and later found 
that younger children exposed to the dust cloud on 9/11/2001 had a 
significant increase in respiratory symptoms while older children 
showed a non-significant increase. No corrosive injuries were reported 
to have occurred in the children studied. Brackbill et al., (2006) 
reported skin rash/irritation in 4% (AOR1.7; p<0.05) of adult survivors 
of collapsed or heavily damaged buildings who were caught in the dust 
and debris cloud, excluding rescue/recovery workers (World Trade Center 
Health Registry (WTCHR) data; n=8418). Perritt et al. (2011) reported 
skin conditions in 4% of WTC workers/volunteers (n=7,810), but did not 
clearly identify the types of skin conditions reported (some may have 
been traumatic injuries such as abrasions, blisters and contusions). 
They also reported eye ailments/illness in 9%, and traumatic eye 
injuries in 6% of the study population, also without a detailed 
description of the injuries. Huang et al., (2012) found skin 
irritation/rashes in 12% of area residents and rescue/recovery workers 
3 years after 9/11, and in 6% after 6 years of WTCHR participants 
(n=42,025). None of these studies identified serious skin injuries 
occuring in the groups studied. Lippmann et al. (2015) reviewed and re-
evaluated many of the previously published test data and reports of 
adverse effects in WTC first responders, worker and others. They 
hypothesized that the unique conditions caused by the WTC tower 
collapse resulted in greater inhalation of large and coarse particles 
(consisting of concrete and gypsum dust, and synthetic vitreous fibers) 
than would be expected to occur, and that these larger irritant 
particles are likely to have caused many of the respiratory injuries in 
exposed WTC workers and others. However, the existing data are 
inadequate to establish the air concentrations of dust components and 
pH of the material they believe are responsible for the respiratory 
injuries identified in the WTC population, so no quantitative 
correlations between exposures and adverse effects can be assessed or 
identified. Further, as discussed above, these injuries, while serious, 
are not consistent with the gross tissue injuries the Agency sought to 
prevent in regulating some wastes as hazardous due to their corrosive 
properties. Finally, the composition of the large particle dust 
Lippmann believes to be the cause of WTC worker respiratory injuries 
appears to be unique to the WTC disaster, making the WTC circumstance a 
poor example of the potential hazards indicative of and associated with 
nationwide waste management practices.
---------------------------------------------------------------------------

    \28\ The dose, or exposure levels in this study were based on 
estimates of the amount of time and distance from the towers 
individuals reported on the day of the tower's collapse (for acute 
exposure) and the thickness of the dust layer in homes, cleaning 
activity, and the amount of time spent in different settings where 
dust was found. As this was a retrospective study, no testing of 
dust composition or properties was conducted.
---------------------------------------------------------------------------

    In their comments (pp. 105-107), petitioners repeat the petition's 
criticisms of data published on the composition and properties of WTC 
dust (particularly its pH) to which workers were or may have been 
exposed, and criticize the Agency's reliance on these data in the 
tentative denial. The petitioners' comments argue that in relying on 
these data as part of the basis of the tentative denial, the Agency 
fails to adhere to EPA data quality and integrity guidance.\29\ The 
tentative denial and today's Notice identify the sources of all data on 
WTC dust and aerosols that have been relied on in evaluating and 
responding to the Petition and comments on the tentative denial. Those 
information sources describe the manner in which dust and other samples 
were collected, the dates and locations for data collection, sample 
handling procedures, and sample testing methods. As discussed above, 
investigators were evaluating a number of different properties of the 
dust and used tests they believed were suited to assessing the dust 
properties they were interested in investigating. The dust pH was 
tested for many samples, using several different approaches, although 
no investigators used the petitioners' preferred test, EPA Method 9045. 
Petitioners believe EPA's reliance on pH data collected using tests 
other than Method 9045 is inappropriate and violates the Agency's data 
quality policies and obligations. However, the pH data the Agency has 
relied on is the WTC dust pH data that exist; there are no WTC dust pH 
data developed using Method 9045 that the Agency is aware of, and the 
petitioners have not identified nor provided the Agency with any WTC 
dust pH data collected using Method 9045. The Agency has therefore 
relied on the existing data that it believes are most relevant for 
evaluating WTC first responder and rescue/recovery/debris removal 
worker and other exposures, despite any shortcomings. The petitioners' 
assertions about the results that may have been produced by evaluating 
the dust using Method 9045 cannot substitute for the data that do 
exist. Because the different investigators describe their methods and 
approaches for evaluating the dust and potential exposures in published 
articles (or in some instances, on government websites) presenting the 
results of research, the test results and their relevance to the 
questions petitioners raise can be evaluated. Therefore, while not the 
testing petitioners would have recommended, petitioner assertions that 
these data are somehow fraudulent, and that the Agency has used them 
inappropriately, are baseless.
---------------------------------------------------------------------------

    \29\ See: Guidelines for Ensuring and Maximizing the Quality, 
Objectivity, Utility and Integrity of Information Disseminated by 
the Environmental Protection Agency, EPA/260R-02-008, October 2002.
---------------------------------------------------------------------------

    The tentative denial also described the types of injuries WTC 
workers exposed to the dust have experienced (81 FR 21303; April 11, 
2016). One of the most frequent types of injury identified in WTC 
workers are different types of chronic decrements in respiratory 
capacity. However, as discussed in the tentative denial, these 
injuries, while quite serious in many cases, are different from the 
injuries the Agency sought to prevent in establishing the corrosivity 
characteristic regulation, and the

[[Page 31632]]

available data do not establish a causal connection between dust pH and 
these injuries. Petitioners have in their comments identified no 
studies reporting gross corrosive injuries (as described in the 1980 
corrosivity regulation background document) in WTC first responders, 
workers at the site, or others. (See petitioner comments pp. 108-115)
    Petitioners further criticize the Agency as conducting a biased and 
incomplete review of the available data. The Agency conducted an 
extensive review of petitioner submitted data as well as additional 
relevant materials identified by the Agency (approximately 400 
references were placed in the public docket supporting the tentative 
denial), and additional studies have been reviewed in the course of 
developing today's Notice and response to comments document. As the 
published scientific literature on the WTC disaster is voluminous, 
comprising hundreds of studies addressing a range of topics, the Agency 
has focused its efforts on data it believes to be most relevant to 
assessing the petitioners' requested regulatory revisions, including 
several studies noted in petitioner comments. This review has included 
primarily data on WTC dust composition and properties (both as settled 
dust and as airborne material) and data on the adverse health effects 
experienced by first responders, site clean-up workers, and others 
potentially exposed to the dust and other pollutants present at the WTC 
site.
    Petitioners also argue that in responding to the petition, the 
Agency did not adequately consider its own guidance on evaluating the 
hazards that might result from exposure to more than one chemical. 
Developing a comprehensive and detailed understanding of the adverse 
health effects suffered by first responders, WTC workers and others 
resulting from their exposures at the WTC site is important work that 
is ongoing by many researchers, and parts of the Agency's technical 
guidance on evaluating multiple or cumulative exposures may be helpful 
in these efforts. However, the Agency's purpose in issuing the 
tentative denial and today's Notice is much narrower. In responding to 
the petitioners' requests for specific revisions to the RCRA 
corrosivity characteristic regulation, the Agency's purpose in 
examining WTC exposures and the resulting adverse health effects is to 
understand whether corrosive injuries resulted from dust or other 
exposures related to waste management at the WTC site, and whether 
revisions to the corrosivity regulation could, in some future incident 
that might result in similar exposures, prevent corrosive injuries. 
Petitioners discussed this question in both the petition and in their 
comments (pp. 96-97) on the Agency's tentative denial of the petition. 
The Agency examined this question extensively in the tentative denial 
and concluded that the injuries suffered were not corrosive injuries as 
that term has been used in the background support materials for the 
RCRA corrosivity regulation (81 FR 21302-21304; April 11, 2016).\30\ In 
addition, the petition did not identify how revised RCRA corrosivity 
regulations could change waste management practices to prevent injuries 
in some future incident that could cause exposures similar to those at 
the WTC disaster site. In response to comments on the tentative denial 
submitted by petitioners and others, the Agency examines these issues 
again in today's Notice and comes to the same conclusions as in the 
tentative denial. Further, petitioners themselves acknowledge that 
establishing that WTC first responders, workers and others suffered 
corrosive injuries is not a critical part of their overall argument for 
revising the corrosivity regulation (See petitioners' comments p. 15).
---------------------------------------------------------------------------

    \30\ GHS relies on the same type of serious injury for defining 
corrosive materials as does the 1980 Corrosivity background 
document. GHS Chapter 3.2.1.1 states: ``Skin corrosion refers to the 
production of irreversible damage to the skin; namely, visible 
necrosis through the epidermis and into the dermis occurring after 
exposure to a substance or mixture.''
---------------------------------------------------------------------------

5. The Petitioners Assert That EPA Misunderstands the Applicability of 
RCRA Regulations to the WTC Dust and Debris (Petition pp 67-70)
    In comments on the tentative denial, petitioners state that ``EPA 
was contending that there were no ``solid wastes'' or ``hazardous 
wastes'' from the WTC that would be subject to any RCRA regulations.'' 
The petitioners' discussion goes on to reference the discussion on 
pages 83 FR 21304-21305 of the tentative denial and concludes that: 
``Clearly, the debris and dust from the WTC collapse met the definition 
of solid waste under RCRA''.
    The discussion of RCRA applicability in the tentative denial 
responded to the petition's failure to describe how the proposed 
changes to the RCRA corrosivity regulation could have reduced the 
hazards to the WTC first responders and other workers, the local 
residents, and others. The tentative denial did not imply that the 
Agency believed no waste management occurred in the course of clearing 
and removing debris from the site and transporting and landfilling it 
at the Fresh Kills landfill.
    However, the available data do not lend themself to identifying 
waste and waste management related exposures to workers, as distinct 
from other exposures. The petition's discussion of WTC exposures 
comingled all potential exposures to all potentially exposed people in 
all settings and did not attempt to distinguish worker exposures that 
may have been related to waste management activities from exposures 
resulting from other activities or in other settings. This issue is 
important in considering the petitioners' requests, as RCRA regulations 
can only apply to waste and waste management activities.\31\ Further, 
there are situations in which determining the RCRA regulatory status of 
a material (i.e., whether it is a waste, and if it is a waste, whether 
it is also a hazardous waste) requires careful consideration, and the 
events at the WTC site represent such a case.
---------------------------------------------------------------------------

    \31\ While all exposures to WTC dust may have posed some hazard, 
only exposures resulting from waste or waste management can be 
controlled using RCRA regulations. To be considered a RCRA solid 
waste a material must be disposed of or abandoned, as described at 
40 CFR 260.10-261.2. Some of the highest exposures to WTC dust, such 
as on the day of the disaster, are clearly not related to waste or 
waste management activities.
---------------------------------------------------------------------------

    The WTC disaster presented a unique and complex set of worker 
activities and potential exposures. At different (and frequently 
overlapping) times, first responders, volunteers and hired contractor 
workers cleared debris for transport to the Fresh Kills landfill in the 
course of searching for survivors and later, to recover human remains. 
While collection, loading, transport and deposit of WTC dust and debris 
at the landfill would normally be considered waste disposal operations, 
this case may be more complex. A primary activity at the Fresh Kills 
landfill was sorting/screening and examining all of the dust and loose 
debris sent there, to identify and recover any human remains or 
personal property of victims. The sorting/screening work was also 
directed at recovering parts of the airliners used to destroy the 
towers for possible future use as evidence in a trial or legal 
proceeding.\32\ Because of these

[[Page 31633]]

ongoing recovery operations, loose debris at the landfill would likely 
not be considered discarded, and so waste, until the recovery 
operations were completed, on July 26, 2002 (Ekenga et al., 2011; Cone 
et al., 2016).\33\ The other major types of debris cleared from the WTC 
site were large chunks of concrete,\34\ and the steel beams that 
supported the buildings. The pieces of concrete would generally have 
been considered waste when being handled for transport to the landfill 
(although some may have been recycled), and many of the steel beams 
were sold as scrap metal for recycling (https://www.chicagotribune.com/news/ct-xpm-2002-01-27-0201270268-story.html; https://edition.cnn.com/2002/WORLD/asiapcf/east/01/23/china.wtcsteel/).
---------------------------------------------------------------------------

    \32\ In a 2011 study, Ekenga, et. al., reported that 4257 human 
remains, and 54,000 personal items were recovered from the dust and 
debris through the screening done at the landfill site. The Agency 
has never considered human remains or material that contains human 
remains to be waste. Also, material that has ongoing potential use 
as evidence in legal proceedings is not considered waste until such 
proceedings conclude and the material is no longer needed. See: 70 
FR 74881, December 16, 2005, and EPA policy memos dated September 5, 
1989; May 9, 1990; January 15, 2010, and August 11, 1988.
    \33\ These two studies of workers transporting and handling 
debris at the landfill did not present any quantitative data on 
debris composition and properties, nor possible exposures from these 
operations, so it is not possible to identify hazards that might 
have been mitigated by RCRA regulations, where they might have been 
applicable.
    \34\ Petitioners' requested revisions to the corrosivity 
characteristic regulation could potentially apply to pieces of 
broken concrete.
---------------------------------------------------------------------------

    The overlapping nature of rescue, recovery, firefighting, 
demolition and debris removal activities at the WTC disaster site, and 
screening for recoverable materials at the landfill, makes it very 
difficult to distinguish between conventional waste management-related 
activities and their potentially associated exposures, and exposures 
unrelated to waste management, and therefore to identify hazards 
attributable to waste and waste management activities. It remains 
unclear whether or how the RCRA corrosivity regulation revisions sought 
by the petitioners may have in this case (or could in some future case 
that may be similar) prevented the worker (and other) exposures and 
injuries, nor do the petitioners clarify this nexus in their petition 
or their comments on the tentative denial.
6. The Petitioners Assert That the Agency Improperly Considered the 
Potential Impact of the Requested Corrosivity Characteristic Revisions
    Petitioner comments assert that in developing the tentative denial, 
the Agency improperly considered information provided by industry 
stakeholders on the possible impacts of changing the corrosivity 
regulation (petitioner comments pp 39-48). While the tentative denial 
was being developed, industry stakeholders met with and submitted to 
the Agency information describing their concerns about the regulatory 
changes sought by the petition. Part of the industry submission 
presented estimates of the potential impact of the regulatory revisions 
being sought by the petitioners on different industries. The Agency 
reviewed and placed these submissions, as well as other communications 
with the industry stakeholders, in the public docket supporting the 
tentative denial. The tentative denial noted that the industry 
estimates were in the docket, and that the Agency did consider them but 
did not evaluate or attempt to verify them (See 81 FR 21306, April 11, 
2016).\35\
---------------------------------------------------------------------------

    \35\ The Administrative Procedure Act requires the Agency to 
consider all public comments on the Tentative Denial. The industry 
stakeholders submitted the same information on possible impacts to 
industries referenced in the tentative denial as comments on the 
tentative denial, so the Agency is obligated to consider them here. 
Although the Agency considered these comments EPA did not fact-check 
or attempt to verify the specific industry estimates because they 
were not part of the basis for EPA's decision-making. The Agency did 
not develop its own assessment of potential impacts of revising the 
corrosivity regulation, as the available data on exposures and 
health effects did not support the need to revise the RCRA 
corrosivity regulations.
---------------------------------------------------------------------------

    Petitioner comments assert that the Agency significantly and 
improperly relied on the industry impact and cost estimates in 
developing the tentative denial and argue that RCRA does not allow the 
consideration of economic impacts in developing RCRA regulations.\36\ 
However, the rationale for tentatively denying the petitioners' 
requests is discussed extensively in the tentative denial, and the 
tentative denial is not based on the potential economic impacts of the 
petitioners' proposals. Rather, the discussion in the tentative denial 
focuses on evaluating the available data on exposures to and adverse 
effects on workers exposed to materials the petitioners identified as 
being of concern and as illustrating the need for revisions to the RCRA 
corrosivity regulations. It does not reference the industry estimates 
of possible economic impacts from a regulatory change. The key data the 
Agency considered in coming to its conclusions include the properties 
of and exposures to dust at the WTC disaster site, cement manufacturing 
facilities, and building demolition events; the type and severity of 
adverse health effects attributable to these exposures; and 
consideration of whether the materials were wastes under RCRA. As 
discussed above, the adverse effects associated with these exposures 
were not corrosive injuries of the type or severity the Agency sought 
to prevent in establishing the corrosivity characteristic regulations. 
At the WTC site, the properties of the dust to which workers may have 
been exposed was also of varying composition and the pH of the dust 
varied at different parts of the site and changed over time with 
exposure to water and ambient air. Also, many WTC dust measurements 
showed pH values less than pH 11, and so these data did not support a 
change in the regulatory pH value to 11.5.
---------------------------------------------------------------------------

    \36\ See, Utility Solid Waste Activities Group v. EPA, 901 F.3d 
414 (D.C. Cir. 2018).
---------------------------------------------------------------------------

    The Agency has separately assessed the hazards of CKD, and despite 
its high pH (pH 10-13), did not find corrosive injury to potentially 
exposed workers.\37\ The Agency further identified a number of studies 
of cement plant workers, including two reviews of these studies. In 
2005, the United Kingdom Health and Safety Executive published a Hazard 
Assessment Document focused on Portland cement dust exposures that 
reviewed 15 studies of exposures to and adverse health effects 
occurring in cement plant workers. Fell and Nordby (2017) conducted a 
systematic literature review that identified 26 research publications 
focused on cement plant exposures and non-malignant respiratory 
effects. While some adverse effects of exposure were identified, 
neither of these reviews identified corrosive injuries among the 
exposed workers. These studies do not distinguish between production 
and waste management-related exposures at the cement plants; however, 
CKD and cement are very similar in composition, and some cement plant 
worker exposures would have included CKD handling and management. Also, 
many of the reviewed studies were of cement production outside the 
U.S., where worker safety protections may be less stringent, and 
exposures may have been higher than is typical in the U.S. The 
investigators presenting these studies conducted medical examinations 
of the exposed workers to identify adverse health effects that may be 
associated with their workplace exposures. The lack of corrosive 
injuries in these exposed worker populations indicates that the CKD and 
cement dust exposures do not result in corrosive injuries, and so do 
not support a need to revise the RCRA corrosivity regulation. These 
reviews and many of the publications reviewed are discussed in greater 
detail

[[Page 31634]]

in the response to comments document accompanying today's Notice.
---------------------------------------------------------------------------

    \37\ As discussed in the tentative denial (81 FR 21306, April 
11, 2016) CKD is an air pollution control residue from cement 
manufacturing activities, for which EPA has made a RCRA status 
determination. See 60 FR 7366, February 7, 1995 and EPA 1997 (Ref: 
Population risks from indirect exposure pathways and population 
effects from exposure to airborne particles from cement kiln dust 
waste, EPA, August 1997 Draft).
---------------------------------------------------------------------------

    Data from instances of dust exposure resulting from building 
demolitions identified by petitioners may have established that there 
have been exposures in these settings, but it did not identify any 
corrosive injuries in people exposed. Further, these examples pose the 
question of distinguishing situations and hazards that might involve 
waste or waste handling (which may be subject to RCRA), from materials, 
activity or hazards not related to waste or waste management. The 
information available to the Agency in this case is not adequate to 
distinguish waste-related exposures from other exposures, particularly 
for the WTC and building demolition exposures; nor do petitioners make 
a distinction between waste-related and non-waste exposures in the 
petition or their comments on the tentative denial. Because the 
available data did not identify corrosive injuries resulting from dust 
exposure, including dust exhibiting pH values between 11.5 and 12.5, 
and were not adequate to identify waste-management related exposures 
(as distinct from other exposures), the Agency concluded that the 
regulatory revisions requested by the petitioners were not warranted.
7. Other Petitioner Comments
    The petitioners also expressed concern that the Agency's tentative 
denial inadequately considered materials on other possible corrosivity 
damage cases and the corrosivity regulations of several states that 
differ from the federal regulations (state waste management 
requirements may be more stringent that the federal requirements). The 
Agency did identify information on these two topics in the course of 
developing the tentative denial, and this information was placed in the 
public docket. However, these issues were not discussed in the 
tentative denial because the Agency concluded that the available 
information did not strongly argue for either changing or not changing 
the corrosivity regulation. In response to petitioner concerns, the 
Agency's assessment of the materials relating to these two issues is 
below.
    As part of assessing the petition, EPA hired a consultant to 
identify and develop a report on any environmental damage cases, or 
incidents, potentially caused by corrosive waste mismanagement that 
have occurred since the corrosivity regulation was established. The 
resulting information was placed in the docket supporting the tentative 
denial. Of the 21 possible damage incidents identified by the 
contractor, one was the WTC site, which is addressed extensively 
elsewhere in this Notice, and four identified acids only or no 
corrosive material. Of the remaining 16 incidents, pH data were 
reported for eight, with four showing pH values above 12.5, two 
reported values less than pH 11.5, and three reported data between pH 
11.5 and 12. At one site without pH data, some amount of sodium 
hydroxide was reported, which would potentially be a newly regulated 
hazardous waste under the petitioners' proposals. CKD mismanagement 
over the period 1984-1993 was identified as the cause of environmental 
damage at nine of the 16 incidents identified, all of which were 
reviewed in the 1994 CKD Report to Congress (see: 59 FR 709, January 6, 
1994 and Tables 5-2 and 5-3 of the report). For seven of these, data 
ranging from pH 11.0-13.6 were reported. None of the incidents reported 
worker or other injuries either before or during remediation.
    These incidents illustrate the fact that potentially corrosive 
wastes have in the past, and may potentially in the future, be 
mismanaged. However, when considered together, these incidents do not 
clearly argue either for or against revision of the current corrosivity 
regulation. The wastes at several sites had pH values less than the 
petitioners' requested value of pH 11.5 (and so would not be regulated 
under the proposed revisions), several others reported pH values above 
the current regulatory standard (and were aqueous wastes), and so were 
already regulated as RCRA corrosive hazardous waste. Wastes at the 
three sites with pH between these values would be newly regulated under 
the petitioners' proposed revisions. Two of these sites had leachate or 
ponded water contaminated with CKD, and the third was a drum 
reconditioner site.
    Petitioners comments also identify a National Priorities List (NPL 
or Superfund) site not considered in the tentative denial, where 
caustic soda (sodium hydroxide) and hydrofluoric acid were found to be 
mishandled by the state of New Hampshire (at the Kearsarge 
Metallurgical Corp site; EPA, 1990). Significant amounts of these 
materials were removed from the site before listing on the NPL, 
although an unspecified amount of potentially corrosive material was 
found in waste piles and in drums buried under the waste piles. 
However, the Record of Decision (ROD) does not provide enough detail to 
understand the relevance of this incident to the petitioners' concerns. 
No pH testing is reported in the ROD, and while some of the material 
was identified as being solid, other material was liquid. No injuries 
to workers or others were reported.
    Petitioners also raise a concern that the tentative denial did not 
specifically address the several states that have waste corrosivity 
regulations that are more stringent or broader in scope than the 
federal regulations, although materials related to these state programs 
were included in the rulemaking docket.\38\ Under RCRA, states may be 
authorized to implement the federal hazardous waste regulatory program 
within their state, and most states have sought and received such 
authorization (RCRA 3006(b)). States are also allowed to set more 
stringent regulatory standards for wastes generated or managed in their 
state, and a number of states have broadened the scope of their 
hazardous waste management regulations beyond the federal requirements. 
These changes may be intended to address hazards from wastes that are 
particular to that state, may reflect state regulatory policy choices 
that are different from federal regulations, or for other reasons. 
These regulations apply only to waste generated or managed within the 
state.
---------------------------------------------------------------------------

    \38\ The agency also reviewed state waste regulations that 
existed in 1980 when developing the existing corrosivity regulation. 
Of the 11 states that already had waste corrosivity regulations, 
eight used pH 12 as their regulatory value, one used pH 11, and two 
used other types of testing to identify corrosive hazardous waste. 
(EPA 1980, PP A1-A2.)
---------------------------------------------------------------------------

    Several states have expanded the scope of the RCRA corrosivity 
regulation for wastes in their states, including California, 
Washington, New Hampshire, Vermont and Rhode Island. All of these 
states expanded their definitions of corrosive waste to include non-
aqueous wastes, but all retained the RCRA regulatory value of pH 12.5 
(or higher). However, Rhode Island has withdrawn its regulation for 
non-aqueous corrosives.\39\ California regulates solid corrosives, but 
excludes waste concrete, cement, cement kiln dust and clinker from 
regulation as corrosive hazardous waste.\40\ The Agency collected some 
data on wastes regulated under these expanded state programs, but they 
were of limited value in considering the petitioners' requests. 
California's waste identification codes do not distinguish between 
aqueous and non-aqueous corrosive waste, so their data would not have 
helped the Agency understand implementation of their non-aqueous 
corrosive waste regulatory

[[Page 31635]]

program. Data from other states also did not provide the Agency with 
much insight about regulating non-aqueous wastes, as they are not 
heavily industrialized states, generate relatively little hazardous 
waste, and may not be representative of more industrialized states and 
the types and volumes of wastes their industries might generate (EPA 
2011, EPA 2020).
---------------------------------------------------------------------------

    \39\ Non-aqueous corrosive wastes were formerly Rhode Island 
Hazardous Waste R004. The R004 designation is identified as 
``reserved'' in Rhode Island's current regulations (250-RICR-140-10-
1).
    \40\ See California Health and Safety Code Sec. 25143.8.
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B. Industry Stakeholder Comments

    A number of different companies and industry groups submitted 
comments on the tentative denial of the corrosivity rulemaking 
petition. One group of 18 trade entities and companies included the 
American Chemistry Council (ACC), American Iron and Steel Institute 
(AISI), the American Fuel & Petrochemical Manufacturers, the Portland 
Cement Association (PCA), and the waste treatment and disposal company 
Waste Management Inc., among others. Other industry commenters include 
the Retail Industry Leaders Association (RILA), the National Ready-
Mixed Concrete Association, the Environmental Technology Council (ETC; 
representing hazardous waste treatment and disposal companies), the 
Utility Solid Waste Activities Group (USWAG; representing 110 energy 
utilities and energy generating companies), and another group of 
industries identifying themselves as the ``RCRA Corrective Action 
Project'' (representing Waste Management, Inc. and apparently other 
Fortune 50 companies not identified in the comment).
    Several of these companies or associations also submitted comments 
on the tentative denial to the Agency as part of the Agency's broad 
regulation review efforts that solicited public comments starting April 
13, 2017 (82 FR 17793, April 11, 2016). New comments were sent by a 
group calling itself the ``Federal Recycling and Remediation Council'' 
composed of a number of industrial companies that believe they might be 
affected by changes to RCRA regulations (although the submission did 
not identify its members), the ACC, and the Holly Frontier Corporation 
(a petroleum refiner).
    These commenters supported the Agency's analysis and conclusions 
presented in the tentative denial and/or urged the Agency to issue a 
final denial of the petition as soon as practicable. These companies 
and organizations identified a number of concerns in expressing their 
opposition to the regulatory revisions sought by the petition. Their 
concerns include a number of possible impacts of the proposed 
regulatory changes, and many commenters' belief that the regulatory 
changes sought would, if implemented, provide no meaningful public 
health benefit (although no risk assessment nor other evaluation was 
submitted in support of this conclusion).
    Industry commenters were concerned about both cost and non-cost 
impacts of the proposed changes. The regulatory changes sought by the 
petitioners would, if implemented, result in more stringent definitions 
for corrosive waste, and/or broaden the scope of the regulation, and so 
more waste would be regulated as corrosive hazardous waste. The 
industry comments on the tentative denial reiterate their earlier 
estimates (submitted to the Agency while the tentative denial was under 
development, and referenced in the tentative denial) of the types and 
volumes of waste generated by facilities from different industries they 
believe would become newly regulated under the proposed revisions, and 
the possible cost of managing such additional waste volumes as RCRA 
hazardous. Industry commenters were also concerned about the impact of 
the proposed regulatory requirements on the use/re-use of certain waste 
materials. As described above, the proposed revisions could have a 
significant impact on the reuse of POTW biosolids as fertilizer.
    Commenters on the tentative denial also identified several non-
economic impacts that could occur under revised corrosivity 
regulations. Commenters representing POTWs expressed concern that 
lowering the regulatory pH value to 11.5 could increase the risk of 
hydrogen sulfide (H2S, a toxic gas) formation in sewer 
systems and exposure to workers, due to both the lower pH, and the 
possible addition of sulfuric acid to wastewater to reduce its pH for 
compliance with wastewater pretreatment requirements. These commenters 
also expressed concern that lower pH wastewater would allow more 
bacterial growth in wastewater treatment systems, which can corrode 
system components. While the water treatment facility concerns may have 
some merit, the degree to which pH reduction pre-treatment may be used 
is not clear, as RCRA generally allows discharges of hazardous 
wastewaters to POTWs under 40 CFR 261.4(a)(1). Therefore, it is not 
clear how much H2S risk might increase under the 
petitioners' proposals. Research on H2S control methods 
indicates pH adjustment below pH 11.5 may continue to be effective, and 
treatment with ferric chloride can precipitate out the sulfur if 
needed. Maintaining pH 8.6-9.0 can reduce the transfer of 
H2S from liquid to the gas phase in sewers, and reduce 
sulfide and methane production, although pH values higher than pH 9.0 
may interfere with treatment plant digester bacteria (Gutierrez et.al., 
2009). However, ``shock dosing'' of sewer systems up to pH 12.5-13.0 
using sodium hydroxide for a short time period is also used in some 
instances (Park et.al., 2014).
    Other commenters identified potential negative impacts to hazardous 
waste treatment methods and operations for other hazardous wastes, and 
to EPA's Land Disposal Restriction (LDR) waste treatment regulatory 
program. Alkaline chemicals are frequently used in stabilization/
solidification treatment of toxic metals occurring in hazardous wastes, 
to immobilize them (by converting metals to insoluble salts, or by 
changing matrix pH to reduce solubility) and reduce possible release to 
the environment (Conner, 1990; EPA, 1991). Also, Portland cement is one 
of the most frequently used materials for solidification/stabilization 
of inorganic hazardous waste. Wastes initially exhibiting the toxicity 
characteristic because of their metals content can, after meeting the 
LDR treatment requirements, be disposed in a non-hazardous waste 
landfill. However, for many metal-bearing wastes, metal compound 
solubility is minimized at or below pH values of 11.0 (CdOH has its 
minimum solubility around pH 11); minimum solubilities for other metal 
oxides occur at lower pHs; (Conner, 1990; Conner and Hoeffner, 1998). 
It is therefore difficult to assess the likely impact of a revised 
corrosivity regulation on treatment of metal-bearing hazardous waste.
    One commenter noted that the petitioned-for revisions could result 
in the regulation of waste concrete as hazardous, a waste they believe 
has been safely managed in construction and demolition (C&D) landfills 
for many years. Review of leachate data from C&D landfills published 
from 1995-2014 indicate an overall pH range of 6.2-8.9 (Lopez and Lobo, 
2014), indicating that disposed concrete is not creating highly 
alkaline conditions in landfills that currently accept it for disposal. 
Further, while the state of California does regulate corrosive solids 
as hazardous within the state, it excludes waste cement, CKD, clinker 
and clinker dust (California Health and Safety Code Sec 25143.8) and 
waste concrete from this designation (CalTrans, 2004).
    Industry stakeholder commenters also believe that the public health 
benefits of revised corrosivity regulations would be minimal. This 
belief is based in part on the lack of a significant number of worker 
injuries or damage cases they have observed during their operations

[[Page 31636]]

related to the handling of wastes that are not regulated as hazardous 
under the current regulation, but that might be regulated under 
regulations incorporating the petitioners' requests. In the course of 
developing the tentative denial, the Agency reviewed several 
information sources to identify injuries or other damage that may have 
resulted from waste the petition would newly regulate (see: 81 FR 
21307, April 11, 2016). These included an OSHA worker injury database, 
damage cases identified in an Agency report as resulting from recycling 
activities, and a report of a contractor search for damage cases that 
might be related to waste the petitioners have sought to regulate. None 
of these sources identified significant corrosive injuries from waste 
management or from aspects of production processes that might pose 
exposures similar to those that might occur during waste management.

C. Other Comments

    Two state environmental agencies submitted comments on the Agency's 
tentative denial. The Michigan Department of Environmental Quality 
(DEQ) supported the tentative denial evaluation of the rulemaking 
petition, and the Agency's conclusions presented there, without further 
comment. The Oklahoma DEQ supported the regulation of corrosive solids, 
also without further comment or discussion.
    A number of comments were also received from individual members of 
the public. These include five law school students, three unaffiliated 
individuals, and four anonymous commenters. The Agency responds to 
these comments in the Response to Comments document accompanying 
today's Notice.

V. EPA's Conclusions and Rationale for Its Final Action Denying the 
PEER/Jenkins Rulemaking Petition To Revise the RCRA Corrosivity 
Hazardous Characteristic Regulation

    The Agency has reviewed and evaluated the key comments, 
information, and arguments submitted by the petitioners and other 
interested stakeholders on the Agency's tentative denial of the 
rulemaking petition, as well as additional relevant information 
identified by the Agency. Based on its evaluation of the information as 
presented in this Notice and in the Response to Comment Document 
accompanying today's Notice, the Agency has concluded that because the 
available information does not support revision of the RCRA corrosivity 
characteristic regulations sought by the petitioners, such revisions 
are unwarranted. Consequently, the Agency affirms its tentative denial 
and presents this Notice of final denial of the PEER/Jenkins petition 
in its entirety.
    In their comments on the tentative denial, the petitioners argue 
that EPA improperly relied on waste treatment and management 
considerations as part of the basis for the corrosivity regulation. 
Petitioners assert that assessments of the inherent hazard of wastes 
should be the only consideration in establishing the corrosivity 
regulation under RCRA, and further, that the Agency is legally 
obligated to promulgate the corrosivity hazard assessments presented in 
GHS and ILO guidance as the RCRA corrosivity regulatory standard. Much 
of the information provided and arguments made by petitioners are 
intended to support this view. The Agency disagrees for several 
important reasons. The Agency has the discretion under RCRA to regulate 
potentially corrosive wastes based on the risks they may pose when 
plausibly mismanaged, and most corrosive waste does not pose the 
extremely high level of hazard posed by acutely hazardous wastes, such 
as wastes that are acutely lethal toxins with very low LD50 
values or explosives or similarly highly reactive compounds. Absent 
evidence of such an acute degree of intrinsic hazard, EPA's approach to 
identifying which wastes are hazardous under RCRA is based on the risk 
posed when waste is mismanaged, which is a key factor to evaluate in 
hazardous waste determinations, and has been used to establish 
regulations for other hazardous characteristics and many hazardous 
waste listings.\41\ All waste, regardless of whether the waste is 
classified as hazardous, is intended to be subject to some level of 
control under RCRA, and for most waste, the intrinsic hazard is only 
one factor considered in determining whether the waste is hazardous 
under RCRA. The Agency has used its discretion to take this approach 
when developing regulations for many hazardous wastes promulgated under 
the authority of RCRA.\42\
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    \41\ In promulgating the RCRA hazardous waste identification 
program, the Agency noted that the purpose of the regulation is to 
identify those wastes which, because of the hazards they may pose in 
transportation, treatment, storage or disposal, should be subject to 
appropriate management requirements under Subtitle C. (45 FR 33090, 
May 19, 1980).
    \42\ The Agency relies on intrinsic hazard as the sole basis to 
classify waste as hazardous for only very highly, acutely toxic 
wastes and a few other wastes that pose extreme hazards regardless 
of how they are managed. See 40 CFR 261.11(a)(2). Other hazardous 
characteristics regulations and many hazardous waste listings 
consider aspects of wast management (e.g., 40 CFR 261.11(a)(3)).
---------------------------------------------------------------------------

    Further, reliance on international guidance in developing 
regulatory programs such as that provided by the ILO or in the GHS, is 
discretionary, and RCRA and other statutes do not reference nor require 
the use of such guidance in developing regulatory programs. As noted, 
the Agency considered the ILO guidance as one factor in establishing 
the corrosivity regulation, but also considered waste management 
practices as part of its determination. Petitioners' assertions that 
only inherent hazard may be considered identifies their disagreement 
with the Agency's approach to regulating hazardous waste. However, the 
program structure developed by the Agency in 1980 is well within Agency 
discretion under RCRA, and has been successfully implemented for more 
than 40 years.
    The other key question regarding the petition concerns whether the 
record compiled for this action indicates that the current corrosivity 
regulation is inadequately stringent to protect human health and the 
environment from mismanagement of potentially corrosive waste, as 
asserted by the petitioners. Petitioners acknowledge that it is not 
necessary to conclude that WTC injuries are corrosive injuries to 
supporting their petition requests. Petitioners nonetheless continue to 
argue that WTC first responder and other injuries have resulted from 
corrosive properties of the WTC dust, without considering that injuries 
may have been due to exposure to high levels of other dust components, 
including pulverized glass, smoke from ongoing fires, or the many toxic 
constituents that have been identified in WTC dust and air samples, or 
the combination of these different exposures. Petitioners also insist 
in the petition and in their comments on the tentative denial that WTC 
injuries are corrosive injuries, despite the fact that research 
publications reporting on studies of the WTC dust-exposed cohorts 
describe primarily chronic respiratory symptoms (such as asthma or 
reduced forced expiratory volume) resulting from their exposure. While 
these are serious symptoms of adverse health effects, none of the 
research publications and reports identified by the Agency, the 
petitioners, or other commenters on the tentative denial, identify the 
type of gross tissue injury the Agency described in the 1980 background 
document and sought to prevent in promulgating the RCRA corrosivity 
characteristic. The Agency's review includes health effects studies of 
first responders, other WTC workers, and area residents, including 
children

[[Page 31637]]

exposed to the WTC dust cloud on the day the towers collapsed. 
Petitioners also criticize much of the data collected on WTC dust 
samples (both settled dust and worker breathing-zone samples) that were 
evaluated to understand exposures and insist that other testing of 
samples was or should have been conducted. They argue that many of the 
studies of WTC dust were inappropriate or invalid because they did not 
use test methods petitioners believe to be more appropriate and 
hypothesize about the likely results of testing using their preferred 
protocols. However, these arguments are speculative, and the Agency 
cannot rely on the petitioners' conjectures and speculations as the 
basis for a regulation. While more systematic collection of human 
exposure and other data concerning the WTC disaster and its aftermath 
may have provided a better basis for evaluating WTC exposures, the 
Agency must rely on the data that do exist.
    Petitioners also fail to connect any particular WTC exposures to 
waste management activities. That is, not all WTC worker and other 
exposures were exposures to waste, but petitioners do not identify 
particular exposures as resulting from waste or waste management, and 
distinguish them from exposures unrelated to waste management 
activities (such as exposure to the dust cloud on the day the towers 
collapsed). Identifying exposures resulting from waste management is a 
necessary part of petitioner arguments to revise the corrosivity 
regulation, as RCRA gives the Agency authority only to control waste 
and waste management and its resulting hazards. The Agency's conclusion 
after examining the existing data related to this issue is that based 
on available data, it is not possible to identify WTC exposures that 
may be related to waste management as distinct from activities and 
exposures unrelated to waste management. Absent a connection to waste 
management activities, RCRA does not apply. The petitioners have also 
not explained their assertion that more stringent RCRA corrosivity 
regulation would have reduced WTC worker exposures and hazards, nor how 
their requested revision of the RCRA corrosivity regulation now would 
reduce risks in a future event.
    Other exposures cited by the petitioners as supporting the need for 
revision of the corrosivity regulations (exposure to CKD and building 
demolition dust) similarly have also not been found to cause corrosive 
injury. Petitioners also identify a Superfund site not considered in 
developing the tentative denial, where caustic soda (sodium hydroxide) 
and hydrofluoric acid were found to be mishandled but were removed from 
the site and disposed before NPL listing, although some residual 
material was found. However, the lack of pH testing or other detailed 
reporting of this material makes it difficult to evaluate its relevance 
to the petitioners' requests. No off-site contamination, ecological 
damage or injuries were identified.
    In consideration of the information and arguments submitted to the 
Agency in response to its tentative denial of the petitioners' 
rulemaking request, and the Agency's evaluation and other relevant 
information identified by the Agency, as described above and in the 
Response to Comments document accompanying today's Notice, the Agency 
has determined that because changes to the existing RCRA corrosivity 
characteristic regulation are not supported by the available 
information, such changes are unwarranted. Consequently, the Agency 
denies the PEER/Jenkins Rulemaking petition to revise the RCRA 
corrosivity regulation in its entirety.

List of Subjects in 40 CFR Part 261

    Environmental protection, Hazardous waste, Incorporation by 
reference, Recycling, Reporting and recordkeeping requirements, 
Recycling.

Barry Breen,
Acting Assistant Administrator, Office of Land and Emergency 
Management.
[FR Doc. 2021-12327 Filed 6-14-21; 8:45 am]
BILLING CODE 6560-50-P