[Federal Register: November 20, 2007 (Volume 72, Number 223)]
[Rules and Regulations]               
[Page 65395-65435]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr20no07-6]                         


[[Page 65395]]

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Part II





Department of Homeland Security





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6 CFR Part 27



Appendix to Chemical Facility Anti-Terrorism Standards; Final Rule


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DEPARTMENT OF HOMELAND SECURITY

6 CFR Part 27

[DHS-2006-0073]
RIN 1601-AA41

 
Appendix to Chemical Facility Anti-Terrorism Standards

AGENCY: Department of Homeland Security.

ACTION: Final rule.

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SUMMARY: This final rule revises the list of chemicals of interest, or 
COI, which the Department of Homeland Security (DHS or the Department) 
included as Appendix A to the Chemical Facility Anti-Terrorism 
Standards Interim Final Rule. Appendix A lists chemicals of interest 
and screening threshold quantities, or STQs. Any facility that 
possesses (or later comes into possession of) the listed chemicals in 
quantities that meet or exceed the STQ for any applicable security 
issue must complete and submit a Top-Screen. This will assist the 
Department in determining whether a facility presents a high level of 
security risk.
    In this final rule, DHS, among other things: (i) Adjusts the STQs 
for certain COI; (ii) defines the specific security issue or issues 
implicated by each chemical of interest, and in some cases, establishes 
different STQs for COI based upon the security issue presented; and 
(iii) adds provisions that instruct facilities on how to calculate the 
quantities of COI that they have in their possession.
    These refinements to Appendix A will assist the Department in more 
precisely identifying facilities that may be designated as high risk, 
while reducing the burden on facilities that possess chemicals in 
smaller amounts.

EFFECTIVE DATES: The effective date of Appendix A to part 27, as added 
on April 9, 2007 (72 FR 17688) and revised by this rule is November 20, 
2007. Additionally, the regulations published in this document are 
effective November 20, 2007. The incorporation by reference of certain 
publications listed in the rule is approved by the Director of the 
Federal Register as of November 20, 2007.

FOR FURTHER INFORMATION CONTACT: Marybeth Kelliher, Chemical Security 
Compliance Division, Department of Homeland Security, 703-235-5263.

SUPPLEMENTARY INFORMATION: Note that for brevity, all references to CFR 
parts will be to parts in Title 6 of the Code of Federal Regulations (6 
CFR), unless otherwise noted.

Table of Contents

I. Background
II. The Final Rule: The Revised List of Chemicals
    A. Overall Approach to Appendix A
    B. Effect of a Final Appendix A
    C. Provisions by Security Issue
    1. Release-Toxics and Release-Flammables
    2. Release-Explosives
    3. Theft/Diversion-Chemical Weapons/Chemical Weapons Precursors
    4. Theft/Diversion-Weapons of Mass Effect
    5. Theft/Diversion-Explosives/Improvised Explosive Device 
Precursors
    6. Sabotage/Contamination
    D. Chemicals With a Specialized Approach
    1. Propane
    2. Chlorine
    3. Ammonium Nitrate
    E. Technical Corrections
III. Discussion of Comments
    A. Specific Chemicals or Types of Chemicals
    1. In General
    2. Propane
    3. Chlorine
    4. Ammonium Nitrate
    5. Acetone and Urea
    6. Chemical Weapons and Chemical Weapons Precursors
    7. Explosives
    8. Hydrogen Peroxide
    B. Coverage of Appendix A
    1. Colleges and Universities
    2. Medical Research Organizations and Similar Laboratories
    3. Farms and the Agricultural Industry; Fumigation Industry
    4. Overlap With Other Federal Entities
    5. Concerns About Being Over-Inclusive
    C. Screening Threshold Quantities
    1. In General
    2. Modifying the ``Any Amount'' STQ
    3. Mixtures and Solutions
    D. Revisions to the COI List
    1. Technical Corrections
    2. Formatting and Approach
    E. Other Comments
    1. Procedural Issues
    2. Compliance Issues
    3. Miscellaneous Comments
IV. Regulatory Analyses
    A. Executive Order 12866: Regulatory Planning and Review
    B. Regulatory Flexibility Act

Abbreviations and Terms Used in This Document

ACG--A Commercial Grade
AN--Ammonium Nitrate
APA--A Placarded Amount
ASP--Alternative Security Program
CAS--Chemical Abstract Service
CGA--Compressed Gas Association
COI--Chemicals of Interest
CSAC--Chemical Security Analysis Center
CSAT--Chemical Security Assessment Tool
CUM 100g--Cumulative STQ of 100 grams for Designated Chemical 
Weapons
CVI--Chemical-terrorism Vulnerability Information
CW--Chemical Weapons
CWC--Chemical Weapons Convention
CWP--Chemical Weapons Precursors
DOT--U.S. Department of Transportation
EPA--Environmental Protection Agency
EXP--Explosives
FBI--Federal Bureau of Investigation
IED--Improvised Explosive Device
IEDP--Improvised Explosive Device Precursors
LNG--Liquefied Natural Gas
NFPA--National Fire Protection Association
NOS--Not Otherwise Specified
NPGA--National Propane Gas Association
RMP--EPA's Risk Management Program
SVA--Security Vulnerability Assessment
SSP--Site Security Plan
STQ--Screening Threshold Quantity
TQ--Threshold Quantity
TSA--Transportation Security Administration
VBIED--Vehicle-Borne Improvised Explosive Device
WME--Weapon of Mass Effect

I. Background

    On October 4, 2006, President George W. Bush signed the Department 
of Homeland Security Appropriations Act of 2007 (the Act), which 
provided the Department of Homeland Security with the authority to 
regulate the security of high risk chemical facilities. See Pub. L. 
109-295, Sec.  550. Section 550 required the Secretary of Homeland 
Security to promulgate interim final regulations ``establishing risk-
based performance standards for security of chemical facilities'' by 
April 4, 2007 and specified that the regulations ``shall apply to 
chemical facilities that, in the discretion of the Secretary, present 
high levels of security risk.'' Id.
    Pursuant to Section 550, on December 28, 2006, the Department 
issued an Advance Notice of Rulemaking (Advance Notice), which 
discussed a range of regulatory and implementation issues. See 71 FR 
78276. By directing the Secretary to issue ``interim final 
regulations,'' Congress authorized the Secretary to proceed without the 
traditional notice and comment required by the Administrative Procedure 
Act. See 71 FR 78276, 78277. The Department, however, saw great benefit 
in soliciting comments on as much of the program as was practicable in 
the short timeframe permitted under the statute and therefore 
voluntarily sought comment on the Advance Notice, including a range of 
significant programmatic issues and regulatory text.
    On April 9, 2007, the Department issued an Interim Final Rule 
(IFR), which responded to the comments to the Advance Notice and 
established a new part 27 to Title 6 of the Code of Federal 
Regulations. See 72 FR 17688. Part 27 establishes risk-based 
performance standards for the security of our Nation's chemical 
facilities. The rule requires covered chemical facilities to prepare 
Security Vulnerability Assessments (SVAs) that identify

[[Page 65397]]

facility security vulnerabilities. The rule also requires covered 
chemical facilities to develop and implement Site Security Plans (SSPs) 
that identify measures that satisfy the identified risk-based 
performance standards. It also allows certain covered chemical 
facilities, in specified circumstances, to submit Alternate Security 
Programs (ASPs) in lieu of an SVA, SSP, or both. In addition, the rule 
contains associated provisions addressing inspections and audits, 
recordkeeping, and the protection of information that constitutes 
Chemical-terrorism Vulnerability Information (CVI). Finally, the rule 
provides the Department with authority to compel compliance through the 
issuance of orders, including orders assessing civil penalties and 
orders to cease operations.
    The IFR, except for Appendix A to part 27, went into effect on June 
8, 2007. Appendix A contained a tentative list of Chemicals of Interest 
(COI). DHS accepted comments on the tentative list of chemicals in 
Appendix A (hereafter referred to as proposed Appendix A or proposed 
appendix) for 30 days until May 9, 2007. With this final rule, the 
Department responds to those comments and provides a final list of 
Chemicals of Interest in Appendix A. The same principles that guided 
the Department during the development of the proposed list have guided 
the Department during the development of this revised list, and those 
main principles are summarized here. First, DHS did not use any single, 
existing list as its sole source or classify all chemicals on any 
existing list in a particular way. Instead, DHS used multiple sources, 
so that it could obtain a more complete picture of the universe of 
facilities that may qualify as high risk. Second, in identifying the 
chemicals and STQs for chemicals, the Department sought to strike an 
appropriate balance: Sufficiently inclusive of chemicals in quantities 
that might present a high level of risk under the statute without being 
overly inclusive and thereby capturing facilities that are unlikely to 
present a high level of risk. Third, the Department has identified 
chemicals by considering security issue(s) associated with a chemical. 
The Department has identified the COI for preliminary screening based 
on the belief that these chemicals, if released, stolen or diverted, 
and/or contaminated, have the potential to create significant human 
life and/or health consequences.

II. The Final Rule: The Revised List of Chemicals

A. Overall Approach to Appendix A

    While the universe of chemicals in Appendix A has remained 
substantially the same, the Department has re-structured the format of 
the appendix and has more clearly defined the provisions associated 
with these chemicals. The Department has included a considerable amount 
of additional information in the appendix as well as some new 
provisions to the regulatory text. The changes that the Department has 
made have come directly from comments or otherwise logically resulted 
from comments where DHS agreed that the comments raised valid points 
and were within the scope of the proposed appendix.
    The proposed appendix listed only a chemical and a corresponding 
Chemical Abstract Service (CAS) number,\1\ however the final appendix 
includes that information as well as a new column with commonly-used 
synonyms for certain chemicals. The final appendix also adds several 
new columns that identify the security issue(s) associated with each 
chemical of interest (COI).\2\ In addition, the Department has assigned 
an STQ and minimum concentration provision to each chemical of 
interest. The final appendix, unlike the proposed appendix, does not 
trigger reporting obligations based on possession of an STQ of ``any 
amount.'' \3\
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    \1\ CAS numbers are unique identifiers for chemical substances.
    \2\ The Department has added definitions for Chemical of 
Interest (COI) and Security Issue to Sec.  27.105 ``Definitions.''
    \3\ See footnote 64.
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    In the final appendix, the Department has listed the security 
issue(s) associated with each chemical of interest. Although these same 
security issues drove the Department's selection of chemicals for 
inclusion in the proposed appendix, the Department did not list (in the 
proposed appendix) the security issue(s) for each particular chemical. 
This additional information provides guidance to regulated entities, so 
that they better understand how to use the appendix, and it explains 
the Department's rationale(s) for including these chemicals, at these 
STQs, on the list.
    The seven columns on the far right of the appendix contain the 
chemical facility security issues that the Department has identified 
for this appendix. There are three main categories of security issues: 
Release, theft/diversion, and sabotage/contamination.\4\ Two categories 
have three subcategories each. The ``release'' category has three 
subcategories: (1) Release-Toxic: Chemicals with the potential to 
create a toxic cloud that would affect populations within and beyond 
the facility, if intentionally released; (2) Release-Flammables: 
chemicals with the potential to create a vapor cloud explosion that 
would affect populations within and beyond the facility, if 
intentionally released; and (3) Release-Explosives: chemicals with the 
potential to affect populations within and beyond the facility if 
intentionally detonated. The ``theft and diversion'' category also has 
three subcategories: (1) Theft/Diversion-Chemical Weapons (CW)/Chemical 
Weapons Precursors (CWP): chemicals that could be stolen or diverted 
and used as CW or easily converted into CW; (2) Theft/Diversion-Weapons 
of Mass Effect (WME): chemicals that could be stolen or diverted and 
used directly as WME; and (3) Theft/Diversion-Explosives (EXP)/
Improvised Explosive Device Precursors (IEDP): chemicals that could be 
stolen or diverted and used in explosives or IEDs. The third category, 
``sabotage/contamination,'' refers to those chemicals that, if mixed 
with other readily-available materials, have the potential to create 
significant adverse consequences for human life or health.
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    \4\ As noted in the IFR and consistent with the definition of 
``security issue'' in Sec.  27.105, the Department recognizes one 
additional security issue--critical to government mission and 
national economy. (DHS has added a definition of security issue in 
this final rule at Sec.  27.105.) The loss or interruption in 
production of certain chemicals, materials, or facilities could 
create significant adverse consequences for national security, the 
national or regional economy, and/or the ability of the government 
to deliver essential services. The Department plans to assess 
currently-available information and to collect new information 
(e.g., through the Top-Screen process) as a means of identifying 
facilities responsible for these types of chemicals. At this time, 
DHS is not including any chemicals in the appendix based on this 
security issue, though it may do so in the future.
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    The Department has established baseline STQs for the chemicals of 
interest for each security issue. (DHS discusses the baselines in this 
preamble and also summarizes the general rules in Table 1: ``Summary of 
General Rules by Security Issue'' at the end of this section). DHS has 
set the STQ for each chemical of interest at the baseline amount for 
that chemical's security issue(s). Where necessary, the Department has 
identified a few exceptions. Most notably, DHS has developed a 
specialized approach for propane, chlorine, and ammonium nitrate.
    Each chemical in Appendix A presents at least one security issue, 
and

[[Page 65398]]

some chemicals present multiple security issues. Where there are 
multiple issues associated with a chemical, a facility must complete 
and submit a Top-Screen if it meets or exceeds the STQ for any of the 
applicable security issues. For example, there are two security issues 
associated with arsenic trichloride: release-toxic and theft/diversion-
CW/CWP. In the Security Issue columns of the appendix, there is a mark 
in the box for release-toxic and for theft/diversion-CW/CWP, and there 
is a STQ (and minimum concentration) listed under the Release column 
and under the Theft column. If the facility meets or exceeds the STQ 
listed in either the Release column or the Theft column (using the 
appropriate calculation provisions discussed below), the facility must 
complete and submit a Top-Screen. The Department has revised the 
regulatory text in Sec.  27.200(b)(2) and Sec.  27.210(a)(1)(i) to 
reflect this change.
    The Department will periodically update the list of chemicals in 
Appendix A and will do so subject to notice and comment. The Department 
may add or remove chemicals, or categories of chemicals, or may change 
STQs based on new or additional information.
    In revising Appendix A, the Department has found it necessary to 
revise the regulatory text, clarifying how facilities should use the 
appendix. The Department added Sec.  27.203, which instructs facilities 
on how to calculate the STQ for a given chemical and Sec.  27.204, 
which addresses mixtures. In this section of the preamble, DHS 
discusses provisions that are general or that apply to multiple 
security issues. DHS discusses provisions related to specific security 
issues in section II(C).
    Section 27.203(a) provides specific exclusions from the calculation 
requirements that apply to chemicals of interest in all security issue 
categories. Facilities need not count chemicals of interest covered by 
these exclusions, because chemicals in such circumstances or forms are 
unlikely to contribute to the potential consequences of a successful 
attack. DHS has adopted several of these exclusions from the 
Environmental Protection Agency's (EPA) Risk Management Program (RMP) 
regulation. Sections 27.203(a)(1)-(5), (6), and (8) track the EPA 
exemptions in 40 CFR 68.115(b)(4)(i)-(iv), 68.115(b)(3), and 
68.115(b)(2)(iii), respectively. The concepts are the same, though DHS 
has adjusted the language to make it consistent with the language in 
part 27 (e.g., whereas EPA considers TQs present at a ``stationary 
source,'' DHS considers STQs at a ``facility''). Note that EPA applies 
these exemptions to release chemicals (i.e., those which it regulates 
under RMP), while DHS applies these exclusions to all part 27 chemicals 
of interest (i.e., to all chemicals associated with the security issues 
of release, theft/diversion, and sabotage/contamination).
    DHS has formulated one other exclusion specifically for this 
regulation. In Sec.  27.203(a)(7), DHS exempts chemicals of interest in 
solid waste (including hazardous waste) regulated under the Resource 
Conservation and Recovery Act (RCRA) (42 U.S.C. 6901 et seq.) DHS does 
not believe that it is necessary for facilities to count COI in RCRA-
regulated solid waste toward their STQ, because the Department does not 
believe that this waste is a likely target of a terrorist attack or 
contains COI that are likely sources of terrorist uses. As stated in 
the regulatory text, though, this exclusion does not apply to waste 
covered by 40 CFR 261.33, ``Discarded commercial chemical products, 
off-specification species, container residues, and spill residues 
thereof.'' This type of waste can include virtually pure chemicals 
(including off-specification products that may merely be inconsistent 
with a customer's specifications) that have been discarded. DHS thinks 
it is important for facilities to include this waste in the STQ 
calculation, because this waste is a potential source of COI that would 
be just as attractive to a terrorist as the chemical product itself.
    Paragraph (b) of Sec.  27.203 addresses STQ calculations related to 
release chemicals. Section 27.203(b)(1) provides instructions 
concerning the substances that facilities shall include when 
determining whether they possess quantities of a release chemical that 
meet or exceed the STQ. Proposed Appendix A did not contain the 
instructions enumerated in Sec.  27.203(b)(1), but further 
consideration and a review of the comments caused DHS to provide these 
instructions. Pursuant to Sec.  27.203(b)(1)(i), facilities must 
include chemicals in a vessel, which, pursuant to 40 CFR 68.3, ``means 
any reactor, tank, drum, barrel, cylinder, vat, kettle, boiler, pipe, 
hose, or other container.'' Facilities must also include chemicals of 
interest stored in magazines, as defined in 27 CFR 555.11. Pursuant to 
that Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) 
definition, a magazine is ``any building or structure, other than an 
explosives manufacturing building used for storage of explosive 
materials.'' In addition, facilities must include chemicals of interest 
in underground storage facilities. For purposes of part 27, an 
underground storage facility refers to a below-ground storage location 
for chemicals of interest or mixtures of chemicals of interest (e.g., 
petroleum-based materials) that are placed in the storage location 
(until needed) after having been extracted from the ground and refined 
or processed. Such facilities include, but are not limited to, depleted 
reservoirs in oil and/or oil gas fields, aquifers, and salt cavern 
formations. DHS understands that certain products (e.g., propane, 
natural gas, petroleum) may be stored in these underground storage 
facilities, and DHS wants to ensure that facilities count this material 
toward the amount of their COI.
    Pursuant to Sec.  27.203(b)(1)(ii), facilities must count chemicals 
of interest in specified transportation containers toward the STQ 
amount for release chemicals. In using this terminology, DHS is 
referring to the same category of transportation containers that EPA 
refers to in its RMP regulation--that is, transportation containers 
used for storage not incident to transportation, including 
transportation containers connected to equipment at a facility for 
loading or unloading and transportation containers detached from the 
motive power that delivered the container to the facility. See 40 CFR 
68.3 (containing a description of transportation containers within the 
definition of ``stationary source''). These transportation containers 
would include, for example, tank cars attached to processing units and 
tank cars detached from motive power that had delivered the tank car to 
the facility.
    While the EPA RMP regulation at 40 CFR 68.3 does not specifically 
mention transportation containers detached from the motive power, EPA 
discusses such provision in its Final Rule titled ``List of Regulated 
Substances and Thresholds for Accidental Release Prevention; 
Amendments'' \5\ and in its Frequently Asked Questions on the EPA Web 
site.\6\ Part 27 (like EPA's RMP regulation) does not require 
facilities to include chemicals of interest in transportation when 
calculating their STQs. DHS adopts the EPA definition of 
transportation, and accordingly considers a container to be in 
transportation as long as it is attached to the motive power (e.g., 
truck or locomotive) that delivered it to the site. If the tank car is 
detached from the motive power, and therefore no longer in 
transportation, the facility must

[[Page 65399]]

consider the contents of the tank car in calculating its STQ.
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    \5\ See 63 FR 640 (January 6, 1998).
    \6\ See FAQ II.C.2 on the EPA Web site at http://yosemite.epa.gov/oswer/ceppoweb.nsf/content/caa-faqs.htm
.

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    Pursuant to Sec.  27.203(b)(1)(iii), facilities must also include 
chemicals of interest that are present as process intermediates, by-
products, and incidental production materials. This means, for example, 
that a refinery must count toward the STQ for hydrogen sulfide the 
quantity of hydrogen sulfide produced as a by-product of any of its 
various processes. Or a facility should count toward the STQ for 37% 
hydrochloric acid the quantity of 37% hydrochloric acid produced from 
the absorption of hydrogen chloride gas into water and stored 
temporarily prior to subsequent dilution below the threshold 
concentration. DHS requires the inclusion of these items in calculating 
the STQ, because while they may not be present at all times, when 
present, they could be released and contribute to the consequences of 
an attack.
    The remaining two subsections in Sec.  27.203(b)(1) are items that 
EPA exempted, but which DHS believes are important to include in this 
regulatory program; they have the potential to create a significant 
offsite impact in the event of a successful attack. First, when 
calculating the amount of a chemical of interest, facilities must 
include chemicals in natural gas or liquefied natural gas (LNG) stored 
in ``peak shaving facilities.'' See Sec.  27.203(b)(1)(iv). Companies 
typically store natural gas or LNG in peak shaving facilities when 
demand for product is low or slows. The natural gas or LNG is stored 
until it is used later during peak consumption periods. EPA excludes 
the chemicals in these peak shaving facilities by virtue of the fact 
that EPA considers them storage incident to transportation, and EPA 
does not subject that type of storage to its RMP regulation.\7\ Within 
DHS, TSA is the lead agency for the security of pipeline transportation 
and of transportation-related facilities; however, such facilities 
(e.g., peak shaving facilities) may be required to provide information 
under part 27. TSA and the Chemical Security Compliance Division will 
work together to ensure that DHS efforts directed at pipelines are 
complementary.
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    \7\ Under the RMP rule, EPA considers there to be a threshold 
quantity of a substance if it is present at a stationary source. 40 
CFR 68.115(a). ``The term stationary source does not apply to 
transportation, including storage incident to transportation, of any 
regulated substance * * *.'' 40 CFR 68.3. EPA ``considers the 
transportation exemption to include storage fields for natural gas 
where gas taken from pipelines is stored during non-peak periods, to 
be returned to the pipelines when needed.'' 63 FR 640, 642 (Jan. 6, 
1998). Because EPA considers this type of storage incident to 
transportation, the type of storage is not subject to EPA's RMP 
rule.
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    Second, facilities must also include chemicals of interest in fuels 
when stored in above-ground tank farms, including tank farms that are 
part of pipeline systems. See Sec.  27.203(b)(1)(v). This includes 
fuels with any one of the four National Fire Protection Association 
(NFPA) flammability hazard ratings and not just fuels with an NFPA 
flammability hazard rating of 4. EPA excludes these fuels by virtue of 
the provisions in its mixtures rule for regulated flammable substances. 
See 40 CFR 68.115(b)(2). These fuels also would have been excluded 
under DHS's flammable mixtures provisions (see Sec.  27.204(a)(2) \8\) 
except that DHS specifically included these fuels through this 
provision here in Sec.  27.203(b)(1)(v), because of concern that they 
could create significant human life or health consequences if an 
intentional attack by a terrorist were successful.
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    \8\ Section 27.204(a)(2) provides that ``except as provided in 
Sec.  27.203(b)(1)(v) for fuels that are stored in aboveground tank 
farms (including farms that are part of pipeline systems), if a 
release-flammable chemical of interest is present in a mixture in a 
concentration equal to or greater than one percent (1%), and the 
mixture has a National Fire Protection Association (NFPA) 
flammability hazard rating of 1, 2, or 3, the facility shall count 
the entire weight of the mixture toward the STQ.'' Without the 
``exception'' clause, DHS would have excluded these fuels by virtue 
of the fact that these fuels are mixtures that likely have NFPA 
flammability hazard ratings of 1, 2, and 3. Pursuant to Sec.  
27.204(a)(2), facilities need not count the entire amount of these 
mixtures (i.e., mixtures with COI present in a concentration equal 
to or greater than one percent (1%) and with a flammability hazard 
rating of 1, 2, or 3) toward the STQ.
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    In Sec.  27.203(c), DHS provides that facilities shall only count 
theft/diversion chemicals of interest that are in a transportation 
packaging. DHS has adopted the Department of Transportation (DOT) 
definition of packaging, which refers to ``a receptacle and any other 
components or materials necessary for the receptacle to perform its 
containment function in conformance with the minimum packing 
requirements of [DOT's Hazardous Materials Regulations].'' See 49 CFR 
171.8. This includes, but is not limited to, cylinders, bulk bags, 
bottles inside or outside of a box, cargo tanks, and tank cars. DHS has 
focused the universe of theft/diversion chemicals of interest in this 
fashion, because the theft/diversion security issue revolves around 
portable and transportable amounts of certain chemicals. DHS is 
concerned about both the theft of portable amounts of these chemicals 
and the diversion of shipments of these chemicals.
    The Department has also added Sec.  27.204, which addresses 
mixtures. It provides a minimum concentration provision for each 
security issue. The Department included this provision in response to 
commenters, who requested guidance on how to treat mixtures of 
chemicals of interest. See Sec.  27.204. A facility must count toward 
the STQ for a given chemical all quantities of that chemical that meet 
or exceed the listed minimum concentration amount. These minimum 
concentration provisions are derived from existing federal regulatory 
programs (including EPA's RMP program and the Department of Commerce's 
Chemical Weapons Convention (CWC)) Regulations, as well as from 
industry technical standards (see, e.g., Standard for Classification of 
Toxic Gas Mixtures, CGA P-20-2003). The specific minimum concentration 
provision for each security issue is discussed in the sections below.
    In calculating chemical amounts, facilities should consider the 
chemicals in their possession within the framework for each of the 
three separate and distinct security issues categories (release, theft/
diversion, and sabotage/contamination). A facility must count each 
chemical of interest in its possession, using the relevant calculation 
provisions for each of the categories, and if the facility possesses an 
amount that meets or exceeds the STQ for any one of the categories 
(i.e., security issues), the facility must complete and submit a Top-
Screen. To illustrate that point, the Department highlights sulfur 
dioxide, which is both a release-toxic (STQ: 5,000 pounds) and theft/
diversion-WME (STQ: 500 pounds).

--Toward the release STQ of 5,000 pounds, a facility must count all 
quantities of sulfur dioxide in vessels and underground storage 
facilities; in transportation containers used for storage not incident 
to transportation, including storage containers connected to equipment 
at a facility for loading or unloading and storage containers detached 
from the motive power that delivered the container to the facility; and 
present as process intermediates, by-products, and material produced 
incidental to the production of a product if they exist at any given 
time.
--Toward the theft/diversion-WME STQ of 500 pounds, a facility must 
count all quantities of sulfur dioxide in a transportation packaging.

    If the facility has 5,000 pounds or more of sulfur dioxide 
aggregated onsite in vessel(s), transportation packaging(s), etc. or 
500 pounds or more of sulfur

[[Page 65400]]

dioxide in transportation packagings (or both), the facility must 
complete and submit a Top-Screen.
    Facilities must consider each security issue framework 
independently. As a result, there may be chemicals of interest that a 
facility counts under more than one security issue framework. That is 
completely appropriate, as there is a different focus (and therefore 
distinct counting and mixtures rules) for each security issue. For 
example, with respect to sulfur dioxide, a facility will count toward 
its release STQ quantities of sulfur dioxide in a tank car when that 
tank car is connected to equipment at the facility for loading and 
unloading and when that tank car is detached from the motive power that 
delivered it to the facility (see Sec.  27.203(b)(1)(ii)) and it will 
count toward its theft/diversion-WME STQ quantities of sulfur dioxide 
in tank cars (see Sec.  27.203(c)). Under both frameworks (release and 
theft), the facility may, in fact, count the same sulfur dioxide. As 
there are separate purposes for each framework, however, this is 
appropriate. The theft-STQ is focused on preventing someone from 
stealing or diverting the shipment of sulfur dioxide in the tank car 
and weaponizing it. The release-STQ is focused on preventing someone 
from intentionally releasing a quantity of sulfur dioxide that could 
affect the population within and beyond the facility.
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    \9\ Specialized STQs apply to ammonium nitrate, chlorine, and 
propane.

                              Table 1.--Summary of General Rules by Security Issue
----------------------------------------------------------------------------------------------------------------
                                                                                                     Minimum
           Security issue                   STQ \9\          COI to exclude    COI to include     concentration
----------------------------------------------------------------------------------------------------------------
Release--Toxic.....................  500-20,000 lbs.......         27.203(a)      27.203(b)(1)      27.204(a)(1)
                                                                27.203(b)(2)      27.204(a)(1)
Release--Flammable.................  10,000 lbs...........         27.203(a)      27.203(b)(1)      27.204(a)(2)
                                                                27.203(b)(2)      27.204(a)(2)
                                                                27.203(b)(3)
Release--Explosive.................  5,000 lbs............         27.203(a)      27.203(b)(1)      27.204(a)(3)
Theft/Diversion--CW/CWP............  CUM 100 grams-220 lbs         27.203(a)         27.203(c)      27.204(b)(1)
Theft/Diversion--WME...............  15-500 lbs...........         27.203(a)         27.203(c)      27.204(b)(2)
Theft/Diversion--EXP/IEDP..........  100-400 lbs..........         27.203(a)         27.203(c)      27.204(b)(3)
Sabotage/Contamination.............  A Placarded Amount...         27.203(a)         27.203(d)         27.204(c)
----------------------------------------------------------------------------------------------------------------

B. Effect of a Final Appendix A

    Under Section 550, the Department has the authority to use its best 
judgment and all available information in determining whether a 
facility presents a high level of security risk. Appendix A will assist 
the Department in determining which facilities present a high level of 
security risk. In Appendix A, the Department has identified chemicals 
of interest (at specified STQs) that trigger preliminary screening 
requirements. If a facility possesses a chemical of interest at or 
above the STQ for any applicable security issue, the facility must 
complete and submit a Chemical Security Assessment Tool (CSAT) Top-
Screen. The STQ is not the threshold for establishing whether a given 
facility is a high risk facility, but it is a threshold for determining 
whether the facility must complete and submit a Top-Screen.
    Only after the Department gathers additional information through 
the Top-Screen process will the Department make a determination \10\ as 
to whether a facility presents a high level of security risk and 
therefore must comply with the substantive requirements in part 27. 
Accordingly, the presence or amount of a particular chemical is not the 
sole factor in determining whether a facility presents a high level of 
security risk; it is not the only indicator of a facility's coverage 
under part 27.
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    \10\ Based on the information the Department receives in 
accordance with Sec.  27.200 and Sec.  27.205 (including information 
submitted through the Top-Screen), the Department makes a 
preliminary determination as to a facility's placement in a risk-
based tier. See Sec.  27.220(a). Following review of a covered 
facility's Security Vulnerability Assessment (SVA), the Department 
makes a final determination as to a facility's placement in a risk-
based tier. See Sec.  27.220(b).
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    Sections 27.200(b)(2) and 27.210 contain the requirements related 
to Appendix A, and those requirements are fully operative upon 
publication of this final rule in the Federal Register. Section 
27.200(b)(2) requires facilities to complete and submit a Top-Screen if 
they possess any of the chemicals identified in Appendix A at or above 
the STQ for any applicable security issue. If a facility possesses even 
one of the chemicals of interest listed in Appendix A at or above the 
applicable STQ, the facility has an obligation to complete and submit a 
Top-Screen. Section 27.210(a)(1)(i) provides the initial submissions 
schedule for facilities that have to submit a Top-Screen pursuant to 
Appendix A.
    Pursuant to Sec.  27.210(a), the Department uses two methods to 
require facilities to undergo preliminary screening (i.e., complete and 
submit a Top-Screen). The first method, found in Sec.  27.210(a)(1)(i), 
is linked to Appendix A. From the effective date of a final Appendix A 
(i.e., this final rule), facilities that possess any of the chemicals 
listed in Appendix A at or above the STQ for any applicable security 
issue will have 60 calendar days to complete and submit a Top-Screen to 
DHS. Facilities that later come into possession of such chemicals at or 
above the STQ for any applicable security issue will have to complete 
and submit a Top-Screen within 60 calendar days of coming into 
possession of such chemicals. See Sec.  27.210(a)(1)(i). In addition, 
covered facilities \11\ have an ongoing obligation to complete and 
update the Top-Screen as provided in Sec.  27.210(d). Covered 
facilities that make material modifications to their operations or site 
must complete and submit a revised Top-Screen within 60 days of the 
material modification. See Sec.  27.210(d).
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    \11\ As used herein, a ``covered facility'' (or ``covered 
chemical facility''), means ``a chemical facility determined by the 
Assistant Secretary to present high levels of security risk. * * *'' 
and differs from a ``chemical facility'' (or ``facility''), which 
refers to ``any establishment that possesses or plans to possess, at 
any relevant point in time, a quantity of a chemical substance 
determined by the Secretary to be potentially dangerous or that 
meets other risk-related criteria identified by the Department.'' 
See Sec.  27.105. Although DHS will require many facilities to 
complete and submit a Top-Screen, DHS will only require covered 
facilities to develop a chemical facility security program (i.e., 
complete a SVA pursuant to Sec.  27.215, develop and implement a SSP 
pursuant to Sec.  27.225, etc.).
---------------------------------------------------------------------------

    The second method, found in Sec.  27.210(a)(1)(ii), allows the 
Department to contact facilities independently of

[[Page 65401]]

Appendix A. Facilities must complete and submit a Top-Screen if the 
Department notifies the facility to do so through a Federal Register 
notice or on an individual basis through written notification. The 
Department may choose to contact facilities in this manner based on new 
or additional information or based on intelligence information about 
terrorists' interest in certain chemicals or certain facilities. The 
Department will specify the time frame for these Top-Screen submissions 
in the written notification. Since the effective date of the IFR, the 
Department has used the second method (i.e., contacting certain 
facilities individually and directing them to complete the Top-Screen). 
With the publication of this final rule, both triggering requirements 
for completing the Top-Screen will be in effect.

C. Provisions by Security Issue

1. Release-Toxics and Release-Flammables
a. Chemicals
    To identify the release chemicals for Appendix A, the Department 
looked to the list of substances in the EPA's RMP rule.\12\ See Tables 
1 and 2 to 40 CFR Sec.  68.130 for release-toxics and Tables 3 and 4 to 
40 CFR 68.130 for release-flammables. The Department had included all 
of the EPA RMP substances in proposed Appendix A,\13\ and aside from 
the exceptions noted below, continues to do so in this final appendix. 
For release-toxics, the Department uses the same listing criteria, 
including the EPA acute toxicity criteria and vapor pressure cut-off, 
which can be found in EPA's final rule, ``List of Regulated Substances 
and Threshold for Accidental Release Prevention; requirements for 
Petitions Under Section 112(r) of the Clean Air Act as Amended.'' See 
59 FR 4478, 4482 (January 31, 1994). EPA includes a toxic substance on 
its RMP list if the substance is an acute toxic that has vapor pressure 
high enough that the release could result in an offsite poisonous 
inhalation hazard.
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    \12\ The Clean Air Act (42 U.S.C. 7401, et seq.) provides that 
the EPA shall promulgate a list of substances that ``in the case of 
accidental release, are known to cause or may reasonably be 
anticipated to cause death, injury, or serious adverse effects to 
human health or the environment.'' See 42 U.S.C. 7412(r)(3).
    \13\ Note that some of these chemicals present not only a 
release issue, but present additional security issue(s) too (e.g., 
theft and diversion or sabotage and contamination).
---------------------------------------------------------------------------

    In this final appendix, the Department has removed three release-
toxic chemicals \14\ that it had included in the proposed appendix. 
While these three toxic chemicals appear on EPA's RMP list, they do not 
meet the RMP listing criteria for vapor pressure. EPA included these 
three chemicals in their RMP list, because Congress specifically 
required their inclusion pursuant to Sec.  7412(r)(3) of the Clean Air 
Act, 42 U.S.C. 7401 et seq.\15\ Because these chemicals do not 
otherwise meet the RMP listing criteria for toxic chemicals, DHS has 
removed them from Appendix A.
---------------------------------------------------------------------------

    \14\ The three release-toxics are: Toluene 2,4-diisocyanate; 
Toluene 2,6-diisocyanate; and Toluene diisocyanate (unspecified 
isomer).
    \15\ In 42 U.S.C. Sec.  7412(r)(3), Congress directed EPA to 
include toluene diisocyanate (TDI) in its RMP list. EPA looked to 
the types of TDI in commercial production (i.e., those types listed 
on the Toxic Substances Control Act Chemical Substance Inventory) 
and listed the three forms noted in footnote 14.
---------------------------------------------------------------------------

    For release-flammable chemicals, DHS also uses the same listing 
criteria as EPA does for release-flammable chemicals. EPA, and now DHS, 
identifies flammable gases and volatile flammable liquids based on the 
flash point and boiling point criteria that the NFPA uses for its 
highest flammability hazard ranking (Class IA). The criteria can be 
found in EPA's Final List Rule. See 59 FR 4478, 4480 (January 31, 
1994).
b. STQ
    DHS set the STQ for release-toxics at the same amount that EPA set 
the Threshold Quantity (TQ) for toxic substances under its RMP 
regulation.\16\ That amount ranges from 500 to 20,000 pounds, depending 
on the toxicity and volatility of the substance. Likewise, DHS set the 
STQ for release-flammables at the same amount as EPA--10,000 pounds. 
The Department has adopted the EPA RMP TQs, because DHS accepts the 
same rationale that EPA used when setting its TQs--i.e., that they are 
amounts that, if released, have the potential to create significant 
human health effects. The Department realizes that, in developing these 
TQs, EPA collected extensive input on and conducted a thorough 
analysis, and DHS wants to leverage that knowledge base.
---------------------------------------------------------------------------

    \16\ See 40 CFR part 68.
---------------------------------------------------------------------------

    Whereas the Department had proposed to set the STQs for these 
release chemicals at seventy-five percent of the EPA RMP TQs in the 
IFR, the Department has instead set these STQs at the same amount as 
the EPA RMP TQs. In doing so, the Department accepted the 
recommendation of many commenters to set the STQ for these release 
chemicals at, rather than below, the EPA RMP TQs. The Department 
realized that it did not need to reduce its STQs to a level below that 
of the EPA TQs, because even though DHS and EPA are seeking to satisfy 
two different mandates (i.e., DHS to prevent an intentional release and 
EPA to prevent an accidental release), DHS has made accommodations for 
that difference. The DHS method for calculating an STQ is more 
conservative than that of the EPA for TQs. Under part 27, except for 
the exclusions listed in Sec.  27.203(a), (b)(2), and (b)(3), a 
facility must aggregate the total amount of COI that it possesses at 
its facility, including COI that may exist in separate processes. By 
contrast, under EPA's RMP regulation, a facility must consider the 
total quantity of a regulated substance ``contained in a process'' that 
exceeds the TQ. See 40 CFR 68.115(a). For example, a facility that has 
multiple processes (involving an RMP substance), with each process 
below the threshold for the reportable TQ, would not be covered under 
RMP. That facility, however, would be covered under part 27 if the 
total quantity of all the processes (associated with a chemical of 
interest) was at or above the STQ.
    DHS believes that, in the case of an intentional terrorist attack, 
chemicals or materials would likely be released from multiple vessels 
rather than a single vessel. As a result, the Department believes that 
setting the STQ at an amount that reflects the entire inventory of the 
facility better captures the potential consequences of an intentional 
attack. The Department believes this is more appropriate than EPA's 
valid assumption for accidents that the worst-case release \17\ would 
be a release from the largest vessel.
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    \17\ In 40 CFR 68.3, EPA defines ``worst-case release'' as ``the 
release of the largest quantity of a regulated substance from a 
vessel or process line failure that results in the greatest distance 
to an endpoint defined in Sec.  68.22(a).''
---------------------------------------------------------------------------

    Despite the general rule for release chemicals (i.e., that the DHS 
STQs are the same as the EPA TQs), there are a few differences between 
the EPA TQs and the DHS STQs. First, as discussed below in section 
II(D)(1), DHS treats propane differently than all other release-
flammables. Second, the RMP TQ for toxic substances applies to all DHS 
release-toxics except for eleven \18\ that meet the RMP listing 
criteria for both toxicity and flammability. EPA treats these 
substances as toxics in its RMP rule; however, DHS lists these 
substances as flammables (and sets the

[[Page 65402]]

STQ at 10,000 pounds), because, in an intentional release, they are 
more likely to act like flammables and potentially create an explosive 
vapor cloud.
---------------------------------------------------------------------------

    \18\ The eleven RMP release-toxics are: ethylene oxide, furan, 
hydrazine, hydrogen selenide, methyl chloride, methyl mercaptan, 
nickel carbonyl, peracetic acid, phosphine, propylene oxide, and 
tetranitromethane.
---------------------------------------------------------------------------

    In calculating whether a facility meets the STQ for release-toxic 
or release-flammable chemicals, the facility need not include release-
toxic or release-flammable chemicals of interest that a facility 
manufactures, processes, or uses in a laboratory at the facility under 
the supervision of a technically qualified individual as defined in 40 
CFR 720.3. See Sec.  27.203(b)(2). DHS adopted this laboratory 
quantities exclusion, including the definition of ``technically 
qualified individual,'' from EPA. The comparable EPA laboratory 
quantities exemption is located in EPA's RMP regulation at 40 CFR 
68.115(b)(5), and EPA's definition of ``technically qualified 
individual'' is located at 40 CFR 720.3(ee). EPA defines a 
``technically qualified individual'' to mean ``a person or persons (1) 
who, because of education, training, or experience, or a combination of 
these factors, is capable of understanding the health and environmental 
risks associated with the chemical substance which is used under his or 
her supervision, (2) who is responsible for enforcing appropriate 
methods of conducting scientific experimentation, analysis, or chemical 
research to minimize such risks, and (3) who is responsible for the 
safety assessments and clearances related to the procurement, storage, 
use, and disposal of the chemical substance as may be appropriate or 
required within the scope of conducting a research and development 
activity.'' Like EPA, the DHS laboratory quantities exclusion does not 
apply to specialty chemical production; manufacture, processing, or use 
of substances in pilot plant scale operations; or activities, including 
research and development, involving chemicals of interest conducted 
outside the laboratory. Facilities that engage in such activities must 
count those chemicals toward their STQ.
    DHS believes that, in a release, a lab quantity of a release 
chemical would not significantly contribute to the consequentiality of 
an attack. Moreover, under this provision, DHS believes that, where lab 
quantities of release chemicals are used, there are appropriate 
controls by virtue of the fact it is done so under the supervision of a 
technically qualified individual. In adding this laboratory quantity 
provision, DHS was responsive to the numerous commenters, including 
those from colleges, universities, and industrial laboratories, who 
requested such a provision.
    As noted above, DHS adopted this laboratory quantities exclusion 
from the EPA. DHS, however, has made one minor clarifying adjustment to 
the language that it adopted from EPA. In response to comments, DHS 
added language to Sec.  27.203(b)(2)(i) to make explicit that 
activities conducted outside the laboratory may include research and 
development activities. A facility must count all quantities of COI 
involved in activities conducted outside of the laboratory (including 
research and development) toward its STQ. In other words, such COI 
would not be subject to the laboratory quantities exclusion.
c. Minimum Concentration (Mixtures)
    Pursuant to Sec.  27.204(a) and as noted in the ``minimum 
concentration'' entries in the appendix, the minimum concentration of a 
release-toxic or release-flammable chemical of interest that a facility 
must include when counting the amount of COI is one percent (1%) by 
weight. Pursuant to Sec.  27.204(a)(1), if a release-toxic chemical is 
present in a mixture, and the concentration of the chemical is equal to 
or greater than one percent (1%) by weight, the facility shall count 
the amount of the chemical of interest in the mixture toward the STQ. 
For example, if a facility has 500 pounds of a toxic mixture containing 
five percent (5%) acrolein, the facility should count five percent (5%) 
of the weight of the mixture, or 25 pounds of acrolein, toward the STQ 
of 5,000 pounds. Except for oleum, if a facility can measure or 
estimate (and document) that the partial pressure of the regulated 
substance in the mixture is less than 10 mm Hg, the facility need not 
consider the mixture when determining the STQ. If a release-toxic 
chemical of interest is present in a mixture, and the concentration of 
the chemical is less than one percent (1%) by weight of the mixture, 
the facility need not count the amount of that chemical in the mixture 
in determining whether the facility possesses the STQ. Note that these 
mixture provisions track those of the EPA in its RMP regulation. See 40 
CFR 68.115(b)(1).
    Pursuant to Sec.  27.204(a)(2), if a release-flammable chemical of 
interest is present in a mixture in a concentration equal to or greater 
than one percent (1%) by weight of the mixture, and the mixture has a 
NFPA flammability hazard rating of 4, the facility shall count the 
entire weight of the mixture toward the STQ. For example, if a facility 
has 500 pounds of a flammable mixture containing five percent (5%) 
pentane and the mixture as a whole has a NFPA flammability hazard 
rating of 4, the facility shall count the entire weight of the mixture, 
or 500 pounds, toward the STQ of 10,000 pounds. If a release-flammable 
chemical of interest is present in a mixture in a concentration equal 
to or greater than one percent (1%) by weight of the mixture, and the 
mixture has a NFPA flammability hazard rating lower than 4 (i.e., NFPA 
hazard rating of 1, 2, or 3), the facility need not count the entire 
weight of the mixture toward the STQ. If a release-flammable chemical 
of interest is present in a mixture, and the concentration of the 
chemical is less than one percent (1%) by weight, the facility need not 
count the mixture in determining whether the facility possesses the 
STQ. Note that these mixture provisions track those of the EPA in its 
RMP regulation. See 40 CFR 68.115(b)(2).
2. Release-Explosives
a. Chemicals
    To identify release chemicals that present an explosive hazard, DHS 
looked to the DOT hazardous materials regulations (see 49 CFR 171-180) 
and the EPA's original listing rule for RMP (see 59 FR 4478 (January 
31, 1994)). DOT identifies explosives as one of nine classes of 
hazardous materials that it regulates and divides explosives (``Class 1 
explosives'') into six divisions. See 49 CFR 173.50(b). Although DHS 
had included explosives from the six DOT explosives divisions in the 
proposed Appendix A, DHS is only including Division 1.1 explosives in 
this final appendix.\19\ After consideration of comments and further 
review, DHS decided to focus on Division 1.1 explosives, which are 
those that have a mass explosion hazard. A mass explosion hazard is one 
which affects almost the entire load instantaneously.
---------------------------------------------------------------------------

    \19\ As a result of that decision, DHS removed chemicals such as 
dinitrosobenzene, sodium dinitro-o-cresolate, sodium picramate, 
tetrazol-1-acetic acid, and zirconium picramate.
---------------------------------------------------------------------------

    DHS has incorporated all of the DOT Class 1, Division 1.1 explosive 
chemicals with only two broad exceptions. First, the Department does 
not include those explosive materials for which DOT uses a generic 
shipping name with the suffix ``N.O.S.'' \20\ This refers to materials 
with generic descriptions in the Hazardous Materials Table in 49 CFR 
172.101 (e.g., Substances, explosive, n.o.s.). The Department has 
instead identified the relevant Class 1 explosive materials as only 
those that DOT specifically names in its Hazardous Materials Table. 
Second, DHS does not include articles

[[Page 65403]]

or devices that DOT lists in its Hazardous Material Table. Examples of 
those articles and devices include charges, guns, detonators, detonator 
assemblies, fuses, primers, cartridges, and motors. DHS does not 
believe, at this time, that it is necessary to include this broader 
universe of substances and materials. Coverage of chemical facilities 
that present a high level of risk and that include these materials will 
be triggered by other STQ provisions of this rule. If the Department 
finds that is not the case for a particular facility, the Department 
will seek information from that facility.
---------------------------------------------------------------------------

    \20\ N.O.S. refers to ``not otherwise specified.''
---------------------------------------------------------------------------

    DHS believes it is appropriate to include DOT Class 1, Division 1.1 
explosive materials in Appendix A despite the EPA's exclusion of these 
materials. At the onset of the RMP program, EPA had listed DOT Division 
1.1 explosives as a regulated substance. EPA set the TQ at 5,000 
pounds, because the EPA believed that a blast wave from such an amount 
had the potential to cause offsite impacts. See 59 FR 4478 (January 31, 
1994). EPA later issued a final rule, delisting Class 1, Division 1.1 
explosives. See 63 FR 640 (January 6, 1998). In the final rule, EPA 
concluded that ``current regulations and current and contemplated 
industry practices promote safety and accident prevention in storage, 
handling, transportation, and use of explosives. As a result, these 
regulations and practices adequately protect the public and the 
environment from the hazards of accidents involving explosives.'' See 
63 FR 640, 641. DHS notes that EPA's decisions were based on safety and 
the prevention of an accidental release. DHS is concerned with an 
intentional attack on an explosives facility, which has the potential 
to generate significant impacts for human life and health beyond the 
facility. Given the different focus of DHS's regulation, it is 
important that DHS consider DOT Class 1, Division 1.1 explosives; there 
is the potential for a serious off-site effect from an intentional and 
successful attack on a facility with these explosives.
b. STQ
    DHS proposed an STQ of 2,000 pounds \21\ for release-explosives but 
now sets the STQ for release-explosives at 5,000 pounds. As discussed 
above in relation to release-toxics and release-flammables, DHS has 
decided to set the STQ for release chemicals at the EPA TQs. Five 
thousands pounds is the TQ that EPA had used for DOT Division 1.1 
explosives when the DOT Division 1.1 explosives were part of the EPA 
RMP program. In addition, this is the same quantity that TSA now 
proposes to use for DOT explosives in its Rail Transportation Security 
NPRM.\22\ All release-explosives are also listed as theft/diversion-
EXP/IEDP chemicals (although all theft/diversion-EXP/IEDP chemicals are 
not listed as release-explosives, because the theft/diversion-EXP/IEDP 
category includes both actual explosives and precursors to explosives). 
A facility that possesses a chemical that presents both a release-
explosive hazard and a theft/diversion-EXP/IEDP hazard must consider 
both of the applicable STQs, and if the facility possesses a quantity 
that satisfies either STQ, the facility must complete and submit the 
Top-Screen.
---------------------------------------------------------------------------

    \21\ In the proposed appendix in the IFR, DHS set the STQ for 
these explosive chemicals at 2,000 pounds. In the IFR, however, DHS 
was only considering the theft/diversion concern. In the IFR, had 
DHS set the STQ for these explosive chemicals (using the method of 
calculating the STQ at 75% of the EPA RMP TQ) based on a release 
concern the STQ would have been 3,750 pounds. As discussed in this 
preamble, while the current EPA RMP does not contain release-
explosives, EPA had previously included release-explosives in the 
RMP program, and when doing so, EPA set the TQ at 5,000 pounds.
    \22\ 71 FR 76852 (December 21, 2006). See proposed 49 CFR 
1580.100(b)(1).
---------------------------------------------------------------------------

    In calculating whether a facility meets the STQ for release-
explosive chemicals, the facility need not include release-explosive 
chemicals of interest that a facility manufactures, processes, or uses 
in a laboratory at the facility under the supervision of a technically 
qualified individual as defined in 40 CFR 720.3. See Sec.  
27.203(b)(2). This provision is identical to the laboratory quantities 
provision that applies to release-toxic and release-flammable chemicals 
and that is discussed above.\23\
---------------------------------------------------------------------------

    \23\ See Sec.  II(C)(1)(b) above.
---------------------------------------------------------------------------

c. Minimum Concentration (Mixtures)
    Section 27.204(a)(3) provides that a facility shall count toward 
the STQ the total quantity of all commercial grades of release-
explosives. DHS has added a definition of ``A Commercial Grade'' (ACG) 
to Sec.  27.105. ACG refers to any quality or concentration of a 
chemical of interest offered for commercial sale that a facility uses, 
stores, manufactures, or ships.
3. Theft/Diversion-CW/CWP
a. Chemicals
    In identifying chemical weapons (CW) and their precursors that are 
at risk for theft or diversion, the Department looked to the chemicals 
covered by the Chemical Weapons Convention (CWC).\24\ The chemicals 
covered by the CWC regulations are divided into three lists, or 
``schedules,'' based on their previous use as a CW or possible utility 
in developing chemical weapons.\25\ Schedule 1 covers chemical weapons 
agents and their immediate precursors. They have very limited 
industrial and medical applications. Schedule 2 covers chemicals and 
precursors that have some industrial uses. Schedule 3 covers chemicals 
and precursors with broad commercial applications, some of which were 
formerly weaponized.\26\
---------------------------------------------------------------------------

    \24\ The Convention on the Prohibition of the Development, 
Production, Stockpiling and Use of Chemical Weapons and on Their 
Destruction is an international arms control, disarmament, and non-
proliferation treaty, which is implemented by 22 U.S.C. 6701, et. 
seq. The Department of Commerce administers the implementing 
regulations. See 15 CFR part 710.
    \25\ Schedule 1 chemicals are provided in Supplement No. 1 to 15 
CFR part 712, Schedule 2 chemicals are provided in Supplement No. 2 
to 15 CFR part 713, and Schedule 3 chemicals are provided in 
Supplement No. 3 to 15 CFR part 714.
    \26\ See ``The Chemical Weapons Convention Regulations: 
Frequently Asked Questions and Answers on Industry Compliance,'' 
U.S. Department of Commerce, Bureau of Industry and Security, 
Publication CWC-006 (Updated May 2006).
---------------------------------------------------------------------------

    While the Department included chemicals from all three Schedules 
\27\ in proposed Appendix A, the Department has only included select 
chemicals from the CWC Schedules in final Appendix A. The Department 
continues to include all specifically identified Schedule 1 chemicals, 
because they are actual CW agents and their immediate precursors. Note 
that, based on comments, the Department has listed these Schedule 1 
chemicals by their individual common name along with their chemical 
name.
---------------------------------------------------------------------------

    \27\ There were a few Schedule 1 chemicals, however, that were 
inadvertently omitted from the proposed appendix.
---------------------------------------------------------------------------

    With respect to Schedule 2 and 3 chemicals, the Department has only 
included those Schedule 2 and 3 chemicals and precursors that are 
``easily weaponizable''--that is, they could be easily converted into 
chemical weapons using simple chemistry, equipment, and techniques.\28\ 
DHS made the determination about ``weaponizability'' after consulting 
with several sources, including the Federal Bureau of Investigation 
(FBI) and the DHS Chemical Security Analysis Center (CSAC).\29\ As a 
result of this approach, the Department removed chemicals that had 
appeared on the proposed list but

[[Page 65404]]

were now determined not to be easily weaponizable (e.g., chloropicrin). 
In addition to including select CWC chemicals, Appendix A also contains 
one other easily weaponizable chemical (triethanolamine hydrochloride) 
from the Australia Group's \30\ ``Export Controls List: Chemical 
Weapons Precursors.''
---------------------------------------------------------------------------

    \28\ Among the Schedule 2 chemicals, DHS included certain 
easily-weaponizable chemicals that are representative of 
``families'' of Schedule 2 chemicals (as opposed to uniquely 
identifiable Schedule 2 chemicals).
    \29\ One of the DHS Science and Technology Centers, the CSAC 
leverages existing Department of Defense (and other) infrastructure 
and capabilities to provide analysis and scientific assessment of 
the chemical threat against the homeland and the American public.
    \30\ The Australia Group is an informal group of countries, 
which aims to allow exporting or transshipping countries to minimize 
the risk of assisting chemical and biological weapon proliferation. 
See http://www.australiagroup.net/en/control_list/precursors.htm.

---------------------------------------------------------------------------

b. STQ and Minimum Concentration (Mixtures)
    DHS has eliminated the ``any amount'' STQ that it used in the 
proposed appendix for theft/diversion-CW/CWP chemicals. In this final 
appendix, DHS has set the STQ for each theft/diversion-CW/CWP chemical 
based on the Schedule from which DHS adopted the chemical. The STQ for 
Schedule 1 chemicals is cumulative, or ``CUM 100g,'' meaning that all 
amounts of Schedule 1 chemicals at a facility count toward the 
cumulative STQ of 100 grams. Section 27.203(c) provides that ``where a 
theft/diversion-Chemical Weapons (CW) chemical is designated by ``CUM 
100g,'' a facility shall total the quantity of all such designated 
chemicals in its possession to determine whether the facility possesses 
theft/diversion-CW chemicals that meet or exceed the STQ of 100 
grams.'' This is an aggregate amount and not a per agent limit. DHS 
added a definition for ``CUM 100g'' to Sec.  27.105 ``Definitions'' and 
included this new provision in Sec.  27.204(b)(1). ``CUM 100g'' is the 
entry for both the STQ and Minimum Concentration columns for all 
Schedule 1 chemicals. DHS decided to use this amount based on the 
recommendation of CSAC, which indicated that this amount merits proper 
security for purposes of preventing theft and diversion to create 
significant human impact and cause widespread panic.
    The STQs for Schedule 2 and 3 chemicals, which are based on their 
ease of weaponization, are 2.2 pounds and 220 pounds, respectively.\31\ 
Unlike the STQ for Schedule 1 chemicals, these STQs are not cumulative. 
For non-Schedule 1 theft/diversion-CW/CWP chemicals of interest that 
are present in a mixture at or above the minimum concentration listed 
in the column in Appendix A, the facility should count the entire 
amount of the mixture toward the STQ. See Sec.  27.204(b)(1).
---------------------------------------------------------------------------

    \31\ The STQ for the chemical from the Australia Group, 
triethanolamine hydrochloride, is 220 pounds.
---------------------------------------------------------------------------

4. Theft/Diversion-WME
a. Chemicals
    To identify chemicals that might be targeted for theft or diversion 
as weapons of mass effect (WME), the Department looked to the DOT 
hazardous materials regulations and considered gases that are poisonous 
by inhalation (PIH). In proposed Appendix A, DHS listed all DOT 
Division 2.3 PIH gases including those in Hazard Zones A through D.\32\ 
In this finalized appendix, the Department has not included Hazard Zone 
D PIH gases (including carbon monoxide and sulfuryl fluoride), because 
they do not rise to a level of consequentiality that warrants inclusion 
as a theft/diversion-WME chemical.\33\ In addition, the Department no 
longer includes methyl bromide on the list of chemicals, because it is 
being phased out of domestic manufacture and use under Clean Air Act 
regulations implementing the United States' obligations as a signatory 
to the Montreal Protocol on Substances that Deplete the Ozone 
Layer.\34\ Thus, given the limited and decreasing availability of 
methyl bromide, the Department does not believe that the potential 
consequences of an attack warrant inclusion of that chemical on the 
list of chemicals in Appendix A.
---------------------------------------------------------------------------

    \32\ DOT defines a ``gas poisonous by inhalation'' in 49 CFR 
173.115(c) and assigns hazard zones in 49 CFR 173.116(a).
    \33\ One Hazard Zone D chemical, ethylene oxide, is listed in 
the final Appendix A, because of its inclusion on EPA's RMP list. 
DHS lists ethylene oxide as a release-toxic but not as a theft-WME 
chemical.
    \34\ Title VI of the Clean Air Act (42 U.S.C. 7671, et seq.), 
which addresses stratospheric ozone protection, directs EPA to 
establish a program for phasing out production and use of ozone-
destroying chemicals, including methyl bromide. These requirements 
are in furtherance of the United States' obligations, as a signatory 
to the 1987 Montreal Protocol on Substances that Deplete the Ozone 
Layer, to limit the production and use of such chemicals. In 2000, 
EPA issued a direct final rulemaking, which allowed for the phased 
reduction in methyl bromide consumption and which extended the 
phase-out to 2005. See 65 FR 70795 (November 28, 2000). EPA has 
further extended the phase-out program until alternatives for all 
critical uses of the chemical are available. See 71 FR 38325 (July 
6, 2006). See also http://www.epa.gov/ozone/mbr/index.html.

---------------------------------------------------------------------------

    In the proposed appendix, with one exception, DHS did not include 
DOT Division 2.3 PIH gases for which DOT uses a generic shipping name 
with the suffix ``N.O.S.'' DHS has done the same in this final 
appendix. N.O.S. refers to materials with generic descriptions (e.g., 
Compressed gas, n.o.s. or Compressed gas, toxic, flammable, corrosive, 
n.o.s. Inhalation Hazard Zone D; or Insecticide gases n.o.s. or 
Insecticide gases, toxic, flammable, n.o.s. Inhalation hazard Zone A). 
The Department has only included PIH gases that the Department of 
Transportation specifically names in the Hazardous Materials Table in 
49 CFR 172.101. In addition, the Department has included germanium 
tetrafluoride.\35\ While that chemical is not specifically named in the 
DOT Hazardous Materials Table, it is often named specifically by 
convention in industry. Given that it can be identified by its specific 
name and following a positive response from commenters as to the 
inclusion of this chemical, the Department decided to retain this 
chemical on the list.
---------------------------------------------------------------------------

    \35\ The DOT shipping name for germanium tetrafluoride is 
``Liquefied Gas, Toxic, Corrosive, n.o.s. (Germanium 
Tetrafluoride)'' if liquid is present and ``Compressed Gas, Toxic, 
Corrosive, n.o.s. (Germanium Tetrafluoride)'' if no liquid is 
present.
---------------------------------------------------------------------------

b. STQ
    DHS has eliminated the ``any amount'' STQ that it used in the 
proposed appendix for theft/diversion-WME chemicals. DHS developed the 
STQs for these chemicals in this final rule based generally upon 
recommendations from the Compressed Gas Association (CGA) in its 
comments to the proposed appendix in the IFR. The STQs for theft/
diversion-WME chemicals vary based on Hazard Zone, thereby taking into 
account their relative toxicity. See 49 CFR 173.116 ``Class 2--
Assignment of Hazard Zone.'' In their comments, CGA indicated that, 
aside from lecture bottles and sample cylinders, the minimum industry 
standard commercial size package for Hazard Zone A PIH gases is five 
(5) pounds, and the minimum industry standard commercial size package 
for Hazard Zone B PIH gases is fifteen (15) pounds. CGA recommended 
that DHS set the STQ for Hazard Zone A at any amount greater than five 
pounds and the STQ for Hazard Zone B at any amount greater than fifteen 
pounds. In this final rule, DHS has set the STQ for Hazard Zone A PIH 
gases, which are the most toxic of PIH gases, at fifteen (15) pounds, 
and the STQ for Hazard Zone B PIH gases at forty-five (45) pounds. 
These two STQs are the equivalent of approximately three standard 
commercial size packages for Hazard Zone A and B PIH gases. These two 
STQs represent quantities of Hazard Zone A and/or Hazard Zone B PIH 
gases that are likely to generate significant consequences, including 
the fact that portable quantities of these PIH gases may be subject to 
theft and/or diversion.

[[Page 65405]]

The STQ for Hazard Zone C PIH gases is 500 pounds. That amount is 
equivalent to approximately five standard industrial gas cylinders. 
Hazard Zone C PIH gases are less toxic than those in Hazard Zones A and 
B, and DHS therefore has concluded that it is unlikely for amounts less 
than 500 pounds to generate a high degree of consequence.
    These general STQ rules apply to all theft/diversion-WME chemicals 
except in two instances. First, DHS has established specialized 
provisions for chlorine, which are discussed below in section II(D). 
Second, DHS set the STQ for two Hazard Zone C PIH gases (hydrogen 
fluoride and boron trichloride) at the STQ associated with Hazard Zone 
B PIH gases--i.e., 45 pounds instead of 500 pounds. Although DOT 
categorizes these substances as Hazard Zone C, industry generally 
treats these gases as Hazard Zone B gases because of their toxic 
properties. Industry commenters recommended, and DHS agreed, that the 
toxic properties of these chemicals warrant a higher degree of scrutiny 
and unique STQ in the security context.
c. Minimum Concentration (Mixtures)
    If a theft/diversion-WME chemical of interest is present in a 
mixture at or above the minimum concentration amount listed in the 
Minimum Concentration column of the appendix, the facility shall count 
the entire amount of the mixture toward the STQ unless a specific 
minimum concentration is assigned in the Minimum Concentration column 
of Appendix A to part 27, in which case the facility should count the 
total quantity of all commercial grades of the chemicals at the 
specified minimum concentration. See Sec.  27.203(b)(2). DHS derived 
the minimum concentrations from the Compressed Gas Association Standard 
for Classification of Toxic Gas Mixtures, CGAP-20-2003.
5. Theft/Diversion-EXP/IEDP
a. Chemicals
    To identify chemicals that could be subject to theft or diversion 
for purposes of creating an explosion or producing an Improvised 
Explosive Device (IED),\36\ the Department considered several sources. 
For proposed Appendix A, the Department included certain DOT Class 1 
explosives.\37\ The Department also included IED precursors that the 
National Research Council recommended for additional control in its 
report titled ``Containing the Threat from Illegal Bombings: An 
Integrated National Strategy for Marking, Tagging, Rendering Inert, and 
Licensing Explosives and Their Precursors.'' \38\
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    \36\ An IED is a device fabricated in an improvised manner that 
incorporates in its design explosives or destructive, lethal, 
noxious, pyrotechnic, or incendiary chemicals. It generally includes 
a power supply, a switch or timer, and a detonator or initiator.
    \37\ See discussion in section II(C)(2) above.
    \38\ The National Academy Press published the Report, which is 
available online at http://www.nap.edu. The National Research Council had 

appointed ``The Committee on Marking, Rendering Inert, and Licensing 
of Explosive Materials'' to address areas related to explosives. 
This final report presents the Committee's conclusions and 
recommendations.
---------------------------------------------------------------------------

    While the universe of theft/diversion-EXP/IEDP chemicals has 
remained substantially the same since the IFR, DHS has added a few 
chemicals (including IED precursors) and deleted a few chemicals at the 
recommendation of the FBI.\39\ The FBI Explosives Unit \40\ recommended 
the inclusion of certain chemicals based on their experience 
investigating IED attacks and evaluating IED components.
---------------------------------------------------------------------------

    \39\ DHS added aluminum (powder), magnesium (powder), 
nitrobenzene, potassium permanganate, sodium azide, sodium 
hydrosulfite, and zinc hydrosulfite.
    \40\ As stated on the FBI website, the FBI Explosives Unit 
``examines evidence associated with bombings. Explosives 
examinations involve the identification and function of the 
components used in the construction of incendiary as well as 
improvised explosive devices. In addition, the Unit performs 
chemical analyses to determine the type of explosive used in an 
improvised explosive or incendiary device, which includes bulk 
substance analysis as well as analysis of the residues left behind 
when an explosive detonates.'' See http://www.fbi.gov/hq/lab/org/eu.htm
.

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    Of note in the realm of deleted chemicals (especially to the many 
commenters who requested their removal), the Department no longer 
includes acetone and urea in the appendix. Given the Department's 
inclusion of concentrated nitric acid and concentrated hydrogen 
peroxide in the appendix, the Department does not believe it is 
necessary to include acetone and urea. The Department is concerned 
about these chemicals, because they can be mixed to create explosives 
(e.g., Triacetone Triperoxide (TATP) includes both acetone and hydrogen 
peroxide). The Department is electing, therefore, to list the more 
critical chemicals (i.e., concentrated hydrogen peroxide and 
concentrated nitric acid) of those mixtures. The effect is to target 
regulation to facilities possessing chemicals of interest to terrorists 
in order to thwart terrorism.
    The Department's decision is supported by the conclusions of the 
National Research Council report. In pertinent part, the National 
Research Council provides:

    It is not feasible to control all possible chemical precursors 
to explosives. Efforts to control access should focus on the 
chemicals identified by the committee as current candidates for 
control in the United States. These chemicals are ammonium nitrate, 
sodium nitrate, potassium nitrate, nitromethane, concentrated nitric 
acid, concentrated hydrogen peroxide, sodium chlorate, potassium 
chlorate, and potassium perchlorate. Urea and acetone also meet the 
criteria for control but are adequately controlled if access to 
nitric acid and hydrogen peroxide is limited.\41\ (Emphasis in the 
original.)

    \41\ See the Executive Summary of the National Research Council 
Report titled ``Containing the Threat from Illegal Bombings: An 
Integrated National Strategy for Marking, Tagging, Rendering Inert, 
and Licensing Explosives and Their Precursors,'' p. 15.
---------------------------------------------------------------------------

    In its discussion of chemicals that pose the greatest threat in the 
United States because of their ability to be used to improvise bombs, 
the National Research Council further discussed nitric acid/urea and 
hydrogen peroxide/acetone:

    Urea can be reacted with nitric acid to produce the explosive 
urea nitrate, the material used in the World Trade Center bombing. 
Urea is a nondetonable, ubiquitous, and inexpensive material with an 
annual production volume in North America of 19 million short tons 
(IFDC, 1997). It is used extensively as a fertilizer, as a 
noncorrosive ice-melting material at public facilities and in 
private homes, and as a reagent in many chemical processes. Because 
urea is a relatively innocuous chemical with a wide range of uses, 
the committee believes that preventing access to urea nitrate for 
illegal purposes is more easily achieved by controlling the other 
critical component required to make an explosive: nitric acid.\42\
---------------------------------------------------------------------------

    \42\ Id. at p. 147.
---------------------------------------------------------------------------

    Nitric acid, which is toxic and highly corrosive, has many 
industrial applications but is not commonly available to the general 
public. For that reason, the committee believes that sales of nitric 
acid are much more traceable than those of urea. Furthermore, 
controls on nitric acid would provide greater leverage in efforts to 
prevent bomb attacks than would controls on urea, because nitric 
acid can be reacted with a wide range of organic materials (e.g., 
cellulose, glycerine, and amines) to produce explosives. Although 
much of the nitric acid produced is used in on-site chemical 
processes, a large amount is shipped in tank cars to chemical 
processing plants or packaged in drums for sale to commercial 
businesses such as etchers and metal platers. All of these uses are 
amenable to good sales record keeping. The committee believes that 
such sales records are probably adequate for current law enforcement 
needs.\43\
---------------------------------------------------------------------------

    \43\ Id. at p. 147.
---------------------------------------------------------------------------

    Hydrogen peroxide can be reacted with acetone to make the 
powerful explosive TATP, which has been used by terrorists abroad 
but not thus far to any great extent in the United States. It can be 
made in large

[[Page 65406]]

quantities but is extremely unstable and dangerous to handle.\44\
---------------------------------------------------------------------------

    \44\ Id. at p. 148.
---------------------------------------------------------------------------

    Acetone, one of the most common organic solvents, can be 
purchased readily from many sources in large quantities. As in the 
case of nitric acid and urea, controlling access to TATP is achieved 
more readily by limiting the availability of hydrogen peroxide than 
by controlling acetone. As with controls on nitric acid, controls on 
hydrogen peroxide would be preferred because hydrogen peroxide can 
be reacted with chemicals other than acetone to produce 
explosives.\45\
---------------------------------------------------------------------------

    \45\ Id. at p. 148.

The Department, after consultation with the FBI Explosives Unit, finds 
persuasive the conclusion of the National Research Council and removed 
acetone and urea from Appendix A. The Department also removed nitro 
urea and urea nitrate, neither of which is commercially available.
    With respect to hydrogen peroxide, the Department has adjusted the 
concentration. In the proposed appendix, the Department listed a 
concentration of ``at least 30%.'' In this final appendix, the 
Department has increased the concentration for hydrogen peroxide to 
35%, a common technical and food grade of hydrogen peroxide. The 
original 30% concentration was based on IED precursor regulations 
proposed in Canada. The Department received comments from various 
industries about the importance of hydrogen peroxide and the most 
common commercial grades of the chemicals. In consultation with the FBI 
Explosives Unit, the Department has revised the concentration it set 
for hydrogen peroxide, believing that this change in concentration will 
not significantly increase the likelihood of missing a high risk 
chemical facility through the part 27 program.
b. STQ
    DHS has changed the STQ for theft/diversion-EXP/IEDP chemicals from 
the proposed amount of 2,000 pounds to 400 pounds. This new STQ equals 
the amount that is likely required to produce a small, vehicle-borne 
IED (VBIED). This STQ applies to all theft/diversion-EXP/IEDP chemicals 
except for (1) ammonium nitrate, which the Department discusses below 
in section II(D)(3) and for (2) a few chemicals where DHS used a 
different STQ at the recommendation of the FBI Explosives Unit. 
Specifically, DHS set the STQ for aluminum powder, magnesium powder, 
and nitrobenzene at 100 pounds instead of 400 pounds, because DHS 
believes that the effect of these particular chemicals at these 
quantities would have the same effect as the other theft/diversion-EXP/
IEDP chemicals at 400 pounds.
c. Minimum Concentration (Mixtures)
    As provided in Sec.  27.204(b)(3), a facility shall count toward 
the STQ the total quantity of all commercial grades of a theft/
diversion-EXP/IEDP chemical at the facility unless a specific minimum 
concentration is assigned in the Minimum Concentration column of 
Appendix A to part 27, in which case the facility should count the 
total quantity of all commercial grades of the chemicals at or above 
the specified minimum concentration. There are specified minimum 
concentrations for a few of the theft/diversion-EXP/IEDP chemicals, 
such as hydrogen peroxide (35%) or ammonium nitrate (nitrogen 
concentration of 23% nitrogen or greater). DHS has added a definition 
of ``A Commercial Grade'' (ACG) to Sec.  27.105. ACG refers to any 
quality or concentration of a chemical of interest offered for 
commercial sale that a facility uses, stores, manufactures, or ships.
6. Sabotage/Contamination
a. Chemicals
    Sabotage/contamination refers to those chemicals that, if mixed 
with other readily-available materials, have the potential to create 
significant adverse consequences for human life or health. The 
Department's list of sabotage/contamination chemicals is substantially 
the same in the final appendix as it was in the proposed appendix.
    Sabotage/contamination chemicals currently include those chemicals 
that are capable of releasing a poisonous gas when exposed to water. In 
identifying the chemicals for this category, the Department referred to 
the table of ``Water-Reactive Materials Which Produce Toxic Gases'' in 
the 2004 Emergency Response Guidebook (ERG 2004).\46\ The ERG 2004 is a 
joint publication of the U.S. Department of Transportation, Transport 
Canada, and the Secretariat of Communications and Transportation of 
Mexico. These materials are listed in the ERG 2004 as incompatible with 
water, because they produce large amounts of Toxic by Inhalation \47\ 
gases when exposed to water.
---------------------------------------------------------------------------

    \46\ The table is located on pages 344-348 of the ERG 2004, 
which is available on the Web at http://hazmat.dot.gov/pubs/erg/gydebook.htm
.

    \47\ Toxic by Inhalation (TIH) is synonymous with Poisonous by 
Inhalation (PIH).
---------------------------------------------------------------------------

b. STQ
    In the proposed appendix, the STQ for sabotage/contamination 
chemicals was 2,000 pounds. The STQ now listed for sabotage/
contamination chemicals is A Placarded Amount (APA). DHS added a 
definition of APA to Sec.  27.105, providing that it refers to the STQ 
for a sabotage/contamination chemical of interest, as calculated in 
accordance with Sec.  27.203(d). Section 27.203(d) provides that ``[a] 
facility meets the STQ for a sabotage/contamination chemical of 
interest if it ships the chemical and is required to placard the 
shipment of that chemical pursuant to the provisions of subpart F of 49 
CFR part 172.'' Subpart F of 49 CFR part 172 contains the DOT 
placarding requirements within the DOT Hazardous Materials regulations.
c. Minimum Concentration (Mixtures)
    As provided in Sec.  27.204(c), a facility shall count toward the 
STQ the total quantity of all commercial grades of a sabotage/
contamination chemical that it possesses unless a specific minimum 
concentration is assigned in the Minimum Concentration column of 
Appendix A to part 27, in which case the facility should count the 
total quantity of all commercial grades of the chemicals at the 
specified minimum concentration. DHS has added a definition of ``A 
Commercial Grade'' (ACG) to Sec.  27.105. ACG refers to any quality or 
concentration of a chemical of interest offered for commercial sale 
that a facility uses, stores, manufactures, or ships.

D. Chemicals With a Specialized Approach

1. Propane
    Propane, a release-flammable chemical, is one of the many RMP 
flammable chemicals that DHS adopted from EPA's RMP list. In the IFR, 
the proposed STQ for propane (an RMP flammable) was 7,500 pounds, which 
is seventy-five percent of the RMP TQ. Using the revised general DHS 
rule for release-flammables, the STQ for propane would be 10,000 
pounds. DHS, however, set the STQ for propane in this final rule at 
60,000 pounds. Sixty thousand pounds is the estimated maximum amount of 
propane that non-industrial propane customers, such as restaurants and 
farmers, typically use. The Department believes that non-industrial 
users, especially those in rural areas, do not have the potential to 
create a significant risk to human life or health as would industrial 
users. The Department has elected, at this time, to focus efforts on 
large commercial

[[Page 65407]]

propane establishments but may, after providing the public with an 
opportunity for notice and comment, extend its part 27 screening 
efforts to smaller facilities in the future. This higher STQ will focus 
DHS's security screening effort on industrial and major consumers, 
regional suppliers, bulk retail, and storage sites and away from non-
industrial propane customers. The minimum concentration and mixtures 
provisions for propane are the same as for all other release-
flammables.
    Pursuant to Sec.  27.203(b)(3), facilities need not include propane 
in tanks of 10,000 pounds or less when calculating whether a facility 
has a total inventory of 60,000 pounds. DHS included this provision, in 
part, because of its desire to exclude farmers and agricultural users 
of propane who routinely have three or more propane tanks \48\ for 
heating their homes and/or their chicken/turkey houses. If DHS listed 
propane at 10,000 pounds (the STQ for all other release-flammable 
chemicals), many more entities, including homeowners, farmers, and 
small businesses, would have to complete and submit the Top-Screen. DHS 
does not expect that such dispersed inventories, often located away 
from population centers, are likely to meet its definition of high risk 
chemical facilities. DHS believes that the revised approach toward 
propane is better geared toward identifying and addressing the risks 
associated with major propane inventories.
---------------------------------------------------------------------------

    \48\ Typical tank sizes include approximately 2,205 pounds and 
4,418 pounds.
---------------------------------------------------------------------------

2. Chlorine
    In the proposed appendix, DHS set the STQ for chlorine at 1,875 
pounds. There are two security issues associated with chlorine, each 
with its own STQ. Using the DHS baseline rules, the STQ for chorine as 
a release-toxic would be 2,500 pounds,\49\ and the STQ for chlorine as 
a theft/diversion-WME chemical would be 45 pounds.\50\ Consistent with 
all other release-toxic chemicals, DHS set the release-toxic STQ for 
chlorine at 2,500 pounds and requires facilities to use the calculation 
and mixtures provisions that apply to all other release-toxic 
chemicals. See Sec. Sec.  27.204(a)(1) and 27.203(b)(1)(i)-(ii).
---------------------------------------------------------------------------

    \49\ DHS used the RMP TQ for release-toxic chemicals, and the 
RMP TQ for chlorine is 2,500 pounds.
    \50\ Chlorine is a DOT Division 2.3 PIH gas in Hazard Zone B, 
and the baseline STQ for Hazard Zone B PIH gases is generally 45 
pounds.
---------------------------------------------------------------------------

    DHS, however, developed a unique approach for chlorine where it 
presents a theft/diversion-WME security issue. Instead of 45 pounds, 
DHS established a higher STQ for the theft-WME STQ for chlorine--500 
pounds.\51\ Five hundred pounds is the equivalent of five standard 100-
pound cylinders. (The minimum concentration for chlorine that presents 
a theft-WME security issue is 9.77%.) Setting the theft/diversion-WME 
STQ for chlorine at 45 pounds would have been both burdensome for 
numerous manufacturers (which are reliant on chlorine as a starting 
material) and difficult for DHS to effectively implement, manage, and 
enforce. The U.S. produces 11 million metric tons of chlorine per year. 
The vast majority of chlorine production is used for processing a wide 
range of paper, plastic, textile, medicine, insecticides, paint, and 
other materials. Chlorine is also used in water and wastewater 
treatment. While most chlorine is consumed at the facility where it is 
produced, four million metric tons are shipped annually in small 
containers, one-ton containers, and cargo tank motor vehicles, and tank 
cars across the country.
---------------------------------------------------------------------------

    \51\ As with all theft/diversion chemicals, facilities must only 
count toward the theft-WME STQ for chlorine those quantities of 
chlorine in transportation packagings. See Sec.  27.203(c).
---------------------------------------------------------------------------

    Given the enormous production, transportation, and importance of 
chlorine, DHS increased the theft/diversion-WME STQ for chlorine from 
45 pounds to 500 pounds. DHS believes that quantities less than 500 
pounds would capture facilities that are unlikely to present 
significant consequences. This amount is considered a portable and 
transportable amount that could be diverted or stolen. Overall, DHS's 
approach toward chlorine recognizes that chlorine is distinct from 
other WME precursors in terms of its broad utility and availability.
3. Ammonium Nitrate (AN)
    In proposed Appendix A, the Department identified only one form of 
ammonium nitrate (nitrogen concentration of 28%-34%) and set the STQ at 
2,000 pounds. Based on the consideration of comments, the Department 
has revised its approach in this final appendix, identifying AN in two 
forms: (1) The DOT Division 1.1 explosive found in 49 CFR 172.101 and 
(2) the more common form frequently used as a fertilizer. DHS assigned 
a STQ to each form. Given the breadth of AN's use and history, DHS has 
crafted a specialized approach to address this chemical's specific 
security concerns.
    The first entry for AN in the appendix addresses AN as an 
explosive. The Department has listed the DOT Division 1.1 explosive: 
Ammonium nitrate [with more than 0.2 percent combustible substances, 
including any organic substance calculated as carbon, to the exclusion 
of any other added substance].\52\ As an explosive, AN presents two 
security issues: Theft/diversion-EXP/IEDP and release-explosive. DHS is 
treating the possible theft/diversion of this form of AN in the same 
way that it is treating all other DOT Division 1.1 explosives.\53\ 
Where a facility has larger amounts of AN as an explosive, there may 
also be release hazards. As that is the case, DHS has set the STQ for 
the possible release of AN as an explosive at 5,000 pounds.\54\ That 
STQ is the same TQ that EPA had set for DOT Division 1.1 explosives 
when EPA included such substances in its RMP rule.
---------------------------------------------------------------------------

    \52\ The entry for this form of AN can be found in the DOT 
Hazardous Materials Regulations at 49 CFR Sec.  172.101.
    \53\ Where AN as an explosive presents a theft-EXP/IEDP security 
issue, the STQ is 400 pounds, and a facility is expected to include 
all amounts of ACG of AN when determining whether it meets or 
exceeds the STQ. And, per Sec.  27.203(c), in calculating this theft 
STQ, facilities need only count amounts in transportation 
packagings.
    \54\ Consistent with the mixtures provision for all release-
explosives (see Sec.  27.204(a)(3)), facilities are expected to 
include all amounts of ACG of AN in calculating the STQ.
---------------------------------------------------------------------------

    The second entry for AN in the appendix addresses the more common 
form of AN in solid form with a nitrogen concentration of 23% or 
greater. This form of AN is largely used in the agricultural community 
and in amounts that typically exceed 400 pounds (the STQ for all other 
theft/diversion-EXP/IEDP chemicals). Given the circumstances 
surrounding its use (i.e., extensive use in the agricultural industry), 
DHS has set the STQ for this form of AN at 2,000 pounds. (This form of 
AN in a mixture will count toward the STQ in a minimum concentration of 
33% or more.) This STQ is geared toward ensuring that DHS secures AN 
inventories at major manufacturing and distribution facilities, as 
opposed to individual farmers involved mainly in the application of AN. 
DHS believes that terrorists are interested in maximizing death and 
injuries from an attack and are, therefore, less interested in 
attacking facilities in rural areas or other areas with low population 
densities.
    DHS referenced many sources in developing this approach. In 
addition to considering DOT and EPA regulations, DHS consulted with 
Departmental experts, such as the DHS Office for Bombing Prevention, 
which administers the Bomb Making Awareness Program, and other federal 
experts, such as the FBI Explosives Unit. The Department's

[[Page 65408]]

approach was further supported by international resources, including 
the British Health and Safety Executive's publication titled ``Storing 
and Handling Ammonium Nitrate'' and Canada's proposed regulations on 
Restricted Components issued pursuant to Canada's Explosives Act.\55\
---------------------------------------------------------------------------

    \55\ The Explosives Regulatory Division (ERD) of Natural 
Resources Canada has posted the proposed regulation on their Web 
site at http://www.nrcan.gc.ca/mms/explosif/pdf/RestrictedComp_e.pdf
.

---------------------------------------------------------------------------

E. Technical Corrections

    DHS made several technical corrections to the chemicals listed in 
Appendix A, and those corrections, many of which are highlighted below, 
improve the accuracy of the list. Many commenters assisted DHS in 
identifying these items. DHS removed the entries for certain chemicals 
(because they were synonyms for already-listed chemicals) and instead 
listed them as synonyms in the new ``Synonyms'' column.\56\ DHS also 
corrected the Chemical Abstract Service (CAS) number for several 
chemicals \57\ and the spelling and/or name of other chemicals.\58\
---------------------------------------------------------------------------

    \56\ This includes, for example, calcium dithionite (already 
listed as calcium hydrosulfite), sodium dithionite (already listed 
as sodium hydrosulfite); zinc dithionite (already listed as zinc 
hydrosulfite); and dimethyl phosphoramido-dichloridate (already 
listed as N, N-dimethyl phosphoramidic dichloride).
    \57\ This includes, for example, chromium oxychloride; DF, 
dinitroresorcinol; dipicrylamine [or] hexyl (formerly listed as 
hexanitrodiphenylamine, which is now listed as a synonym); 
hexyltrichlorosilane; magnesium aluminum phosphide (now listed 
separately as magnesium phosphide and aluminum phosphide); octonal; 
octolite; sodium phosphide; strontium phosphide; torpex (formerly 
listed as hexotonal); and trinitronaphthalene.
    \58\ This includes, for example, 1-pentene; boron trifluoride 
(and its synonym borane, trifluoro); boron trifluoride compound with 
methyl ether (1:1); pentaerythritol tetranitrate; propyl 
chloroformate; sulfur tetrafluoride (and its synonym sulfur 
fluoride); and vinyl acetylene.
---------------------------------------------------------------------------

    In addition, DHS made chemical-specific edits. For example, DHS 
separated the entry for ``hydrogen fluoride/hydrofluoric acid (conc. 
50% or greater)'' into two entries. DHS had included them as one 
listing in the proposed listing, because they were included as such on 
EPA's RMP list. As they are two different chemicals (one is a gas and 
the other is a fuming liquid), albeit with the same CAS number, DHS has 
separated them into two entries.\59\ As another example, DHS clarified 
the inclusion of various explosive chemicals. The Department added RDX/
cyclotrimethylenetrinitramine (CAS 121-82-4), which had been 
inadvertently omitted in the proposed appendix. The Department is 
including this DOT Division 1.1 explosive, because the Department is 
including all such DOT Division 1.1 explosives, given the risk of their 
theft or diversion for terrorism purposes. The Department now lists HMX 
under its common name (i.e., HMX); in the proposed appendix, the 
Department had listed HMX under its chemical name 
(cyclotetramethylenetetranitramine). Note, however, that the Department 
has included HMX's chemical name in the synonym column for the HMX 
entry.
---------------------------------------------------------------------------

    \59\ For hydrofluoric acid (conc. 50% or greater), which 
presents a release-toxic security issue, DHS assigns a STQ of 1000 
pounds and minimum concentration of 50% or greater. For hydrogen 
fluoride (anhydrous), when it presents a release-toxic security 
issue, DHS assigns a STQ of 1,000 pounds and a minimum concentration 
of 1.00%. For hydrogen fluoride (anhydrous), when it presents a 
theft-WME security issue, DHS assigns a STQ of 15 pounds and a 
minimum concentration of 42.53%.
---------------------------------------------------------------------------

III. Discussion of Comments

    In the Interim Final Rule, DHS sought comment on the proposed list 
of DHS Chemicals of Interest in Appendix A to part 27. DHS received 
approximately 4,300 public comments, and almost 4,000 of those comments 
were related to the issues surrounding propane. Commenters to the 
proposed appendix included trade associations, citizens, companies, 
universities, hospitals and research facilities, and members of 
Congress. In the sections below, DHS provides a topical summary of the 
comments and responses to those comments.

A. Specific Chemicals or Types of Chemicals

1. In General
    Comment: Commenters suggested that DHS should remove chemicals that 
are widely used in the U.S., (e.g., acetone, chlorine, propane, sodium 
nitrate, urea), asserting that such chemicals should not be regulated 
as a chemical security risk. Some argued that commonly available 
chemicals are unlikely targets of theft from a facility. Other 
commenters provided specific arguments why DHS should not regulate 
commonplace chemicals: Carbon monoxide is a common byproduct that can 
occur frequently in everyday locations (e.g., from a car, heater, or 
furnace). Hydrogen sulfide is a natural byproduct that is easily 
generated, whether in labs during reactions or from geothermal 
facilities.
    Yet other commenters thought that there was only limited harm from 
other chemicals, and so DHS should not regulate those chemicals. For 
example, potassium nitrate and sodium nitrate do not ignite on their 
own, therefore the explosive hazard from those chemicals is reduced, 
and so DHS should not regulate these chemicals on their own. And, the 
flashpoint of triethanolamine, at 212 degrees Fahrenheit, is so high 
that it would have to be extremely hot for the chemical to heat up, 
ignite, and become an explosive hazard.
    Response: The Department has included the chemicals of interest in 
Appendix A due to their potential, when used as part of an attack, to 
create significant human life or health consequences. Each of these 
chemicals presents at least one of the security issues described in 
section II above. Not only has the Department carefully weighed the 
value of including any given chemical, but the Department has clearly 
defined the parameters for each chemical. In this final rule, the 
Department has replaced the ``any amount'' STQs (that it proposed in 
the IFR) with numerical quantities. The Department has also provided 
instruction on how a facility should calculate an STQ and how a 
facility should consider chemicals of interest in a mixture. See 
Sec. Sec.  27.203 and 27.204.
    In addition, the Department reiterates that possession of a 
chemical of interest listed in Appendix A does not equate to coverage 
under the standards in part 27. Possession of a chemical of interest at 
the listed STQ is merely a trigger for a facility to complete and 
submit a Top-Screen. Furthermore, when a facility completes a Top-
Screen, that information becomes but one factor in the Department's 
determination of whether a facility presents a high level of security 
risk.
    In response to the comments about specific chemicals, the 
Department replies as follows: DHS removed carbon monoxide from the 
list as part of its larger decision to remove DOT Division 2.3 PIH 
gases in Hazard Zone D. Carbon monoxide is a Hazard Zone D PIH gas. DHS 
continues to list hydrogen sulfide on the list, because it meets the 
Department's criteria for both release-toxic and theft/diversion-WME 
chemicals. EPA lists hydrogen sulfide as a release-toxic on its RMP 
list. Aside from the exceptions noted above, DHS has included as 
release-toxics in Appendix A all of the toxics on EPA's RMP list. Also, 
DOT identifies hydrogen sulfide as a Division 2.3 PIH gas, Hazard Zone 
B. Aside from the exceptions noted above, DHS has included all of the 
DOT Division 2.3 PIH gases as theft/diversion-WME chemicals in Appendix 
A. DHS, however, excludes naturally occurring sources (such as 
geothermal operations) of hydrogen sulfide pursuant to Sec.  
27.203(a)(9). DHS continues to list potassium nitrate and sodium 
nitrate, although they are

[[Page 65409]]

common oxidizers, they could be used to create IEDs. Finally, DHS 
continues to list triethanolamine, because it can be easily converted 
into a chemical weapon, not because of the flashpoint or other physical 
characteristics of the chemical itself.
    Comment: Commenters remarked on how some Appendix A chemicals of 
interest, such as acetone, propane, and urea, are preferable to 
possible substitutes not on Appendix A, due to their comparatively 
lower toxicity or environmental impact. In particular, they noted that 
the inclusion of certain chemicals means that facilities, in an attempt 
to avoid going through the screening process, will transition away from 
Appendix A chemicals and possibly toward more dangerous substitutes. 
For example, in lieu of acetone, facilities might transition to the use 
of more toxic solvents.
    Response: With respect to the specific chemicals mentioned, DHS 
notes that, for the reasons discussed above, DHS has removed acetone 
and urea from the list of chemicals, and it has substantially revised 
the STQ for propane. As for concerns that facilities will transition to 
more dangerous substitute chemicals, DHS makes the following points. 
Appendix A is DHS's first attempt to identify chemicals of interest 
around which there are serious security concerns, and the aim of 
Appendix A is to provide a screening tool for the DHS chemical security 
regulatory program. If there is a need to address different or 
additional chemicals in the future, DHS has the option of revising 
Appendix A, subject to notice and comment when appropriate, to include 
any different or additional chemicals. The Department also has the 
ability to reach out directly to facilities it believes may present a 
high level of security risk, even for chemicals not included in 
Appendix A. See 27 CFR 27.210(a)(1)(ii).
    While facilities covered by part 27 have flexibility in deciding 
how to meet the part 27 requirements (for example, a facility can 
choose to reduce, substitute, or eliminate its inventory of an Appendix 
A chemical of interest at any time), DHS will, through its review of 
Site Security Plans and visits to facilities, determine whether 
facilities have adequately selected, developed, and implemented risk-
based measures designed to satisfy the risk-based performance 
standards. See 27 CFR 27.225 and 27.245.
    Comment: One association recommended that DHS exclude from the list 
anhydrous ammonia used for food refrigeration and contained in closed-
loop refrigeration systems. Another individual, however, supported DHS 
inclusion of facilities that use anhydrous ammonia either for 
refrigeration during food processing and storage or as part of emission 
controls for coal-fired electrical generation, because such facilities 
are typically near population centers and transportation systems. 
Several other commenters urged DHS to increase the 7,500 pound STQ for 
anhydrous ammonia, so that it would match the TQ for other regulatory 
programs.
    Response: As a toxic chemical utilized across industries, DHS 
believes that anhydrous ammonia can present a high risk and, under 
certain circumstances, generate major consequences for human life or 
health. Therefore, DHS continues to include anhydrous ammonia in the 
list of chemicals. DHS, however, raised the STQ for anhydrous ammonia 
to 10,000 pounds. That tracks the amount that EPA uses in its RMP 
regulation. See 40 CFR 68.130, Table 1. DHS expects that facilities 
will count toward their STQ the quantity of anhydrous ammonia stored as 
part of a refrigeration system in addition to the quantity of anhydrous 
ammonia in the actual system
    Comment: Manufacturing plants pointed out that most plants need a 
minimum inventory of nitric acid to operate efficiently. Commenters 
assert that 2,000 pounds, the amount proposed in Appendix A, is too low 
to operate efficiently, and therefore, large numbers of manufacturing 
plants would have to go through the Top-Screen process. Other 
commenters remarked that nitric acid is included in the inventory of 
laboratories at colleges and universities.
    Response: The Department continues to include nitric acid in 
Appendix A given the security risks it presents. In large quantities, 
nitric acid presents a release hazard, and so DHS has set the STQ at 
15,000 pounds. In addition, DHS is aware that nitric acid, in smaller 
quantities, is useful in creating IEDs. DHS has set the STQ for 
divertible quantities of nitric acid (i.e., amounts in transportation 
packagings) at 400 pounds.
2. Propane
    In proposed Appendix A, the Department included propane on the list 
of Chemicals of Interest (COI) with a STQ of 7,500 pounds.
    Comment: DHS received almost 4,000 comments related to propane, and 
many of these comments disagreed with the proposed inclusion of propane 
and the proposed STQ for propane. There were comments from propane 
distributors and retailers; agricultural businesses; private citizens; 
and numerous small business, including forklift operators, camp 
grounds, parks, bakeries, and construction companies.
    Agricultural businesses indicated that they use propane for 
multiple purposes, including heating their chicken and/or turkey 
houses, drying produce, or keeping livestock and farm produce warm. 
They indicated that many farms have multiple tanks of propane and that 
the regulation will impact many small, family-owned farms, which will 
have to complete the Top-Screen. Others pointed out that these propane 
tanks on farms are often separated by a significant distance or a 
building.
    Propane distributors and retailers indicated that their main 
customer base is residential, commercial/industrial, motor fuel, 
agricultural, and wholesale. In the residential market, propane is used 
primarily for home heating, water heating, and cooking purposes. Many 
commenters stated that a significant percentage of their customer base, 
including residential users, would have to complete and submit a Top-
Screen under the proposed threshold. They speculated that this might 
force propane users to shift to other more environmentally hazardous 
fuel sources. Retailers and distributors also claimed that customers 
had already begun to request the completion and submission of the Top-
Screen on their behalf.
    Commenters asserted that the worst case scenario of an explosion 
from a 1,000 gallon tank of propane is only approximately 500 feet for 
a 1 psi over-pressure condition. While that type of incident is enough 
to break windows and cause injuries due to glass shrapnel, they did not 
think it would be likely to cause structural damage and, hence, should 
not be considered as a national security threat.
    Many commenters felt that that DHS had gone beyond the limitations 
contained in Section 550 of the Department of Homeland Security 
Appropriations Act of 2007, which they asserted provides that nothing 
in the rules can supersede other federal laws pertaining to the 
manufacture, distribution in commerce, use, or sale of chemicals. See 
Section 550(f). Commenters offered suggestions for revisions. Many 
commenters suggested that DHS should incorporate the statutory 
exemptions from EPA's Risk Management Program rules, including the 
statutory exemptions from the Chemical Safety Information, Site 
Security, and Fuels Regulatory Relief Act (Pub. L. 106-40). Commenters 
also proposed that DHS add a footnote to the Appendix A entry for 
propane, indicating that regulated entities need not count all propane 
storage tanks of

[[Page 65410]]

less than 1,200 gallons toward the threshold amount.
    Response: The Department continues to include propane in the list 
of chemicals in Appendix A. The Department has not adopted the 
statutory exemption from the Chemical Safety Information, Site 
Security, and Fuels Regulatory Relief Act (Pub. L. 106-40). That Act 
amended the Clean Air Act to remove flammable fuels from the list of 
substances with respect to which reporting and other activities are 
required under the risk management plan program, and for other 
purposes. EPA codified that provision at 40 CFR 68.126. Congress did 
not include such a provision exempting propane in the authorizing 
legislation for part 27, and so DHS has not exempted propane from part 
27. The Department disagrees with the statement that the Department has 
gone beyond the limitations contained in Section 550. The listing of 
propane in Appendix A merely triggers the requirement that a facility 
(possessing the listed amount) complete and submit a Top-Screen to DHS. 
That, in no way, supersedes any other federal law regulating 
manufacture, sale, or use of propane.
    The Department, however, has changed several provisions related to 
propane, as discussed in section II(D)(1). The Department believes its 
approach to securing significant stocks of propane is informed, 
manageable, and proportionate to its existing use and risk profile. In 
response to the comment about propane storage tanks, the Department 
notes that, per Sec.  27.203(b)(3), DHS will not require facilities to 
include quantities of propane in tanks of 10,000 pounds or less.
3. Chlorine
    In proposed Appendix A, the Department included chlorine on the 
list with an STQ of 1,875 pounds.
    Comment: Many commenters provided input on DHS's inclusion of 
chlorine on the COI list. The majority of commenters encouraged DHS to 
use the EPA RMP TQs for all RMP release-toxic chemicals, including 
chlorine. They argued that the RMP TQ of 2,500 pounds is a well-
reasoned number and that the chemical industry is familiar with that 
number. As an additional argument against an STQ of 1,875 pounds, 
commenters argued that large amounts of chlorine are readily available 
through production or purchase given its diversified uses in and across 
the water treatment, electronics, steel, pharmaceutical, and plastics 
industries. Similarly, other commenters asserted that water and 
wastewater treatment facilities possess chlorine, however those 
locations are not chemical facilities in a traditional sense and 
therefore they are lower risk locations.
    By contrast, one individual commenter recommended a lower STQ for 
chlorine. The commenter suggested that DHS should lower the STQ for 
chlorine to 150 pounds, which is the size of a commonly available 
commercial cylinder. The commenter was concerned that the theft of 
small containers of chlorine would enable a terrorist to use chlorine 
gas in attacks on public gatherings.
    Response: While the Department recognizes the importance of 
chlorine to the Nation's critical infrastructure and key resources, and 
especially the chemical sector, the Department also realizes that the 
theft/diversion of chlorine to develop a WME is a serious security 
concern. Recent terrorist incidents involving chlorine cylinders in 
Iraq have reinforced this concern. To balance these concerns, the 
Department has developed a revised approach toward chlorine, which is 
discussed in section II(D)(2) above. With this approach, the Department 
hopes to facilitate the introduction and implementation of security 
standards that prevent the theft or diversion of chlorine for terrorist 
purposes without unduly interfering with the continued, legitimate 
production, transportation, and use of chlorine. In response to the 
comment about public water systems and water treatment systems, the 
Department notes that it has excluded those systems consistent with the 
statutory exclusion in Section 550 (see Sec.  27.110(b)).
4. Ammonium Nitrate (AN)
    In proposed Appendix A, the Department included ammonium nitrate 
(nitrogen concentration of 28%-34%) on the list of COI with a STQ of 
2,000 pounds.
    Comment: There were several comments about AN with most commenters 
supporting the inclusion of AN on the COI list. Several commenters 
remarked on the reduced availability of AN fertilizer due to liability 
concerns over its use in terrorism. Commenters expressed differing 
opinions on the percentage of nitrogen in AN that DHS should consider 
for purposes of preventing AN's use as an explosive precursor. 
Commenters requested clarification of the STQ and whether it applied to 
solid, liquid, and/or mixtures of AN.
    Response: DHS revised its approach toward ammonium nitrate, as 
discussed above in section II(D)(3). This revised approach recognizes 
that AN is integral to the agriculture and explosives industries, yet 
also seeks to satisfy the DHS mandate to enhance the security of 
facilities that present a high level of risk.
5. Acetone and Urea
    In proposed Appendix A, the Department included acetone and urea on 
the list, each with an STQ of 2,000 pounds.
    Comment: The Department also received a large number of comments on 
acetone and urea. Commenters from a wide array of industries remarked 
on the important uses and widespread availability of these two 
chemicals. Commenters noted that, while other regulatory regimes cover 
acetone and urea, they typically do so for amounts lower than the 
proposed STQ of 2,000 pounds.
    Response: The Department's initial concerns around acetone and urea 
centered on its potential theft and diversion for use as an explosives 
precursor. After considering the comments received and consulting with 
expert sources, including the FBI Explosives Unit and the report 
produced by the National Research Council, the Department does not 
believe that acetone and urea need to be tracked as closely the 
Department tracks other explosives precursors, especially concentrated 
hydrogen peroxide and nitric acid. The Department has removed acetone 
and urea from the list of Chemicals of Interest in Appendix A.
6. Chemical Weapons (CW) and Chemical Weapons Precursors (CWP)
    Comment: While commenters supported the Department's reference to 
the Schedules of chemicals from the CWC, commenters generally noted 
that applying an STQ of ``any amount'' for all CWC chemicals was 
unnecessarily low. With the exception of Schedule 1 chemicals, which 
are weapons and therefore merit a relatively low STQ, commenters 
thought that the ``any amount'' STQ would create unreasonable 
compliance challenges for facilities. Commenters urged DHS to use the 
CWC Schedule 2 TQs for Schedule 2 CW/CWP chemicals. Commenters also 
remarked on the widespread commercial use of triethanolamine (a 
Schedule 3 chemical) in and across the chemical, personal care, and 
consumer products industries.
    Response: The Department has replaced all ``any amount'' STQs for 
theft/diversion-CW/CWP chemicals with numerical quantities. The 
Department did not use the CWC TQs for Schedule 2 chemicals because 
those

[[Page 65411]]

amounts are too high. Those higher amounts are designed to prevent the 
development of state-level chemical weapons programs, not to prevent 
acts of chemical terrorism. DHS identified the STQ for Schedule 2 
chemicals (at 2.2 pounds) by identifying how much one would need of the 
chemical to convert it easily into a weapon using simple chemistry. DHS 
included triethanolamine and several other Schedule 3 chemicals in the 
final appendix due to the ease with which they may be weaponized.
7. Explosives
    Comment: The American Pyrotechnics Association requested that DHS 
remove four oxidizers (ammonium perchlorate greater than 15 microns in 
size, potassium chlorate, potassium nitrate, and potassium perchlorate) 
from the list of chemicals in Appendix A. The American Pyrotechnics 
Association explained that, while these chemicals are used in 
pyrotechnic mixtures, they would neither create a highly toxic cloud 
nor could they be used in an explosive, flammable, or reactive manner 
until they were properly blended with an energetic fuel. In order to 
create an oxidizer and fuel bomb, one must go through extensive and 
difficult steps to obtain the materials and then must have the proper 
training to mix the chemicals in the proper ratio. In other words, 
terrorists would have to complete extensive measures to secure 
chemicals that would do very little damage. Commenters noted that 
neither DOT nor ATF classify the four oxidizers as explosives, and so 
therefore DHS should not either.
    Response: DHS has considered the American Pyrotechnics 
Association's comments and, based on consultations with expert sources 
(including the FBI Explosives Unit) the Department has determined that 
it is still desirable to include these four oxidizers on the list of 
chemicals in Appendix A. DHS is including ammonium perchlorate on the 
list, because it is a DOT Class 1, Division 1.1 explosive that presents 
two security issues (see section II(C) above): theft/diversion-EXP/IEDP 
and release-explosive. It is at risk of theft and misuse for making 
explosives, and it could present a release hazard from a successful 
attack on a facility with a large (5,000 pounds or greater) inventory.
    DHS is including the three potassium compounds (potassium chlorate, 
potassium nitrate, and potassium perchlorate), because they are IED 
precursors that warrant enhanced security. The National Research 
Council listed these chemicals in its report titled Containing the 
Threat from Illegal Bombings: An Integrated National Strategy for 
Marking, Tagging, Rendering Inert, and Licensing Explosives and Their 
Precursors. The FBI's Explosives Unit has validated such conclusions 
for DHS.
8. Hydrogen Peroxide
    Comment: Given the availability of acetone, one commenter requested 
that DHS remove acetone from the list and retain hydrogen peroxide at 
30%, if DHS was concerned about these chemicals being misused to make 
Triacetone Triperoxide (TATP). Commenters from the food, feed, steel, 
cleaning, and other industries remarked on the varied uses for 
commercial strength hydrogen peroxide as well as hydrogen peroxide 
formulations. The majority of commenters recommended that DHS adopt 
OSHA's and EPA's standard approach to listing hydrogen peroxide at a 
52% concentration under their Process Safety Management (PSM) 
regulations and Risk Management Program (RMP), respectively.
    Response: DHS listed hydrogen peroxide in the proposed Appendix A 
and continues to list it as a theft/diversion-EXP/IEDP chemical in 
final Appendix A because of its proven potential as an IEDP. In the 
final appendix, the Department listed ``hydrogen peroxide 
(concentration of at least 35%)'' on the list of chemicals and also set 
the minimum concentration for hydrogen peroxide at 35%. For a 
discussion of the Department's approach to hydrogen peroxide, see 
section II(C)(5) above.
    Commenters have requested that DHS use a 52% concentration for 
hydrogen peroxide, which they assert would be consistent with certain 
OSHA and EPA standards. While DHS understands industry's preference for 
consistent rules across federal agencies, DHS notes that DHS's mandate 
is distinct from other federal agencies that already regulate hydrogen 
peroxide. Both OSHA and EPA are concerned with accidental release and/
or the detonation of hydrogen peroxide and so regulating concentrations 
of 52% or greater is reasonable given their mandates. DHS is charged 
with ensuring effective security at high risk chemical facilities. The 
security issue around hydrogen peroxide, a common IED precursor, 
demanded that DHS identify the concentration at which hydrogen peroxide 
is potentially useful to terrorists as an IED precursor. DHS, in 
consultation with the FBI, has determined that concentration to be at 
or above 35%. In any event, setting the Appendix A concentration at 35% 
for triggering the Top-Screen requirements in no way precludes any 
facility from meeting OSHA or EPA standards.

B. Coverage of Appendix A

1. Colleges and Universities
    Comment: Colleges, universities, and university medical centers; 
associations that represent these institutions; and individuals 
associated with such institutions requested that DHS exempt these 
institutions or modify the rule to address the use of chemicals of 
interest at these institutions. Many colleges