60432 Federal Register / Vol. 73, No. 198 / Friday, October 10, 2008 / Proposed Rules 

ENVIRONMENTAL PROTECTION 

AGENCY 

40 CFR Part 63 

[EPA–HQ–OAR–2008–0008; FRL–8724–5] 

RIN 2060–AO91 

National Emission Standards for 

Hazardous Air Pollutant Emissions: 

Group I Polymers and Resins 

(Epichlorohydrin Elastomers 

Production, HypalonTM Production, 

Nitrile Butadiene Rubber Production, 

Polybutadiene Rubber Production, and 

Styrene Butadiene Rubber and Latex 

Production); Marine Vessel Loading 

Operations; Mineral Wool Production; 

Pharmaceuticals Production; and 

Printing and Publishing Industry 

AGENCY: Environmental Protection 

Agency (EPA). 

ACTION: Proposed rule. 

SUMMARY: This proposed action requests 

public comment on the residual risk and 

technology reviews for nine industrial 

source categories regulated by five 

national emission standards for 

hazardous air pollutants. The five 

national emission standards and nine 

source categories include: National 

Emissions Standards for Group I 

Polymers and Resins (Epichlorohydrin 

Elastomers Production, HypalonTM

Production, Nitrile Butadiene Rubber 

Production, Polybutadiene Rubber 

Production, and Styrene Butadiene 

Rubber and Latex Production); National 

Emission Standards for Marine Vessel 

Loading Operations; National Emission 

Standards for Hazardous Air Pollutants 

for Mineral Wool Production; National 

Emission Standards for Pharmaceuticals 

Production; and National Emission 

Standards for the Printing and 

Publishing Industry. The underlying 

national emission standards that are 

under review in this action limit and 

control hazardous air pollutants. 

We are proposing that no revisions to 

the five national emission standards 

regulating these nine source categories 

are required at this time under section 

112(f)(2) or 112(d)(6) of the Clean Air 

Act. 

DATES: Comments. Comments must be 

received on or before November 24, 

2008. 

Public Hearing. If anyone contacts 

EPA requesting to speak at a public 

hearing by October 20, 2008, a public 

hearing will be held on October 27, 

2008. 

ADDRESSES: Submit your comments, 

identified by Docket ID No. EPA–HQ– 

OAR–2008–0008, by one of the 

following methods: 

• http://www.regulations.gov. Follow 

the on-line instructions for submitting 

comments. 

• E-mail: a-and-r-Docket@epa.gov. 

• Fax: (202) 566–9744. 

• Mail: U.S. Postal Service, send 

comments to: EPA Docket Center 

(2822T), Docket ID No. EPA–HQ–OAR– 

2008–0008, 1200 Pennsylvania Avenue, 

NW., Washington, DC 20460. Please 

include a total of two copies. 

• Hand Delivery: In person or by 

courier, deliver comments to: EPA 

Docket Center (2822T), EPA West 

Building, Room 3334, 1301 Constitution 

Ave., NW., Washington, DC 20004. 

Please include a total of two copies. 

Such deliveries are only accepted 

during the Docket’s normal hours of 

operation, and special arrangements 

should be made for deliveries of boxed 

information. We request that a separate 

copy of each public comment also be 

sent to the contact person listed below 

(see FOR FURTHER INFORMATION CONTACT). 

Instructions: Direct your comments to 

Docket ID No. EPA–HQ–OAR–2008– 

0008. EPA’s policy is that all comments 

received will be included in the public 

docket without change and may be 

made available online at http:// 

www.regulations.gov, including any 

personal information provided, unless 

the comment includes information 

claimed to be confidential business 

information (CBI) or other information 

whose disclosure is restricted by statute. 

Do not submit information that you 

consider to be CBI or otherwise 

protected through http:// 

www.regulations.gov or e-mail. The 

http://www.regulations.gov Web site is 

an ‘‘anonymous access’’ system, which 

means EPA will not know your identity 

or contact information unless you 

provide it in the body of your comment. 

If you send an e-mail comment directly 

to EPA without going through http:// 

www.regulations.gov, your e-mail 

address will be automatically captured 

and included as part of the comment 

that is placed in the public docket and 

made available on the Internet. If you 

submit an electronic comment, EPA 

recommends that you include your 

name and other contact information in 

the body of your comment and with any 

disk or CD–ROM you submit. If EPA 

cannot read your comment due to 

technical difficulties and cannot contact 

you for clarification, EPA may not be 

able to consider your comment. 

Electronic files should avoid the use of 

special characters, any form of 

encryption, and be free of any defects or 

viruses. For additional information 

about EPA’s public docket, visit the EPA 

Docket Center homepage at http:// 

www.epa.gov/epahome/dockets.htm. 

Docket: All documents in the docket 

are listed in the http:// 

www.regulations.gov index. Although 

listed in the index, some information is 

not publicly available, e.g., CBI or other 

information whose disclosure is 

restricted by statute. Certain other 

material, such as copyrighted material, 

will be publicly available only in hard 

copy. Publicly available docket 

materials are available either 

electronically in http:// 

www.regulations.gov or in hard copy at 

the EPA Docket Center, Docket ID No. 

EPA–HQ–OAR–2008–0008, EPA, West 

Building, Room 3334, 1301 Constitution 

Avenue, NW., Washington, DC. The 

Public Reading Room is open from 8:30 

a.m. to 4:30 p.m., Monday through 

Friday, excluding legal holidays. The 

telephone number for the Public 

Reading Room is (202) 566–1744, and 

the telephone number for the EPA 

Docket Center is (202) 566–1742. 

FOR FURTHER INFORMATION CONTACT: For 

questions about this proposed action, 

contact Ms. Mary Tom Kissell, Office of 

Air Quality Planning and Standards, 

Sector Policies and Programs Division, 

Coatings and Chemicals Group (E143– 

01), U.S. Environmental Protection 

Agency, Research Triangle Park, NC 

27711; telephone number: (919) 541– 

4516; fax number: (919) 685–3219; and 

e-mail address: kissell.mary@epa.gov. 

For specific information regarding the 

modeling methodology, contact Ms. 

Elaine Manning, Office of Air Quality 

Planning and Standards, Health and 

Environmental Impacts Division, Sector 

Based Assessment Group (C539–02), 

U.S. Environmental Protection Agency, 

Research Triangle Park, NC 27711; 

telephone number: (919) 541–5499; fax 

number: (919) 541–0840; and e-mail 

address: manning.elaine@epa.gov. For 

information about the applicability of 

these five national emission standards 

for hazardous air pollutants (NESHAP) 

to a particular entity, contact the 

appropriate person listed in Table 1 to 

this preamble. 


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Federal Register / Vol. 73, No. 198 / Friday, October 10, 2008 / Proposed Rules 60433 

TABLE 1—LIST OF EPA CONTACTS FOR GROUP I POLYMERS AND RESINS, MARINE VESSEL LOADING, MINERAL WOOL, 

PHARMACEUTICALS, AND PRINTING AND PUBLISHING

NESHAP for: OECA contact 1 OAQPS contact 2

Polymers and Resins Production, Group I .............................................. Scott Throwe, (202) 564–7013, 

throwe.scott@epa.gov.

David Markwordt, (919) 541–0837, 

markwordt.david@epa.gov. 

Marine Vessel Loading Operations .......................................................... Maria Malave, (202) 564–7027, 

malave.maria@epa.gov.

David Markwordt, (919) 541–0837, 

markwordt.david@epa.gov. 

Mineral Wool Production .......................................................................... Scott Throwe, (202) 564–7013, 

throwe.scott@epa.gov.

Jeff Telander, (919) 541–5427, 

telander.jeff@epa.gov. 

Pharmaceuticals Production .................................................................... Marcia Mia, (202) 564–7042, 

mia.marcia@epa.gov.

Randy McDonald, (919) 541–5402, 

mcdonald.randy@epa.gov. 

Printing and Publishing Industry .............................................................. Len Lazarus, (202) 564–6369, lazarus.leonard@epa.gov.David Salman, (919) 541–0859, 

salman.dave@epa.gov. 

1OECA stands for EPA’s Office of Enforcement and Compliance Assurance. 

2OAQPS stands for EPA’s Office of Air Quality Planning and Standards. 

SUPPLEMENTARY INFORMATION: Regulated 

Entities. The nine regulated industrial 

source categories that are the subject of 

this proposal are listed in Table 2 to this 

preamble. Table 2 is not intended to be 

exhaustive, but rather provides a guide 

for readers regarding entities likely to be 

affected by the proposed action for the 

source categories listed. These 

standards, and any changes considered 

in this rulemaking, would be directly 

applicable to sources as a Federal 

program. Thus, Federal, State, local, and 

tribal government entities are not 

affected by this proposed action. The 

regulated categories affected by this 

action include: 

TABLE 2—NESHAP FOR NINE

INDUSTRIAL SOURCE CATEGORIES

Category NAICS1

code 

MACT 2

code 

Epichlorohydrin 

Elastomers Production ........................ 325212 1311 

Hypalon TM Production ........................ 325212 1315 

Nitrile Butadiene 

Rubber Production 325212 1321 

Polybutadiene Rubber Production ....... 325212 1325 

Styrene Butadiene 

Rubber and Latex 

Production ............. 325212 1339 

Marine Vessel Loading ......................... 4883 0603 

Mineral Wool Production ........................ 327993 0409 

Pharmaceuticals Production ................... 3254 1201 

Printing and Publishing Industry ...... 32311 0714 

1 North American Industry Classification 

System. 2 Maximum Achievable Control Technology. 

To determine whether your facility 

would be affected, you should examine 

the applicability criteria in the 

appropriate NESHAP. If you have any 

questions regarding the applicability of 

any of these NESHAP, please contact 

the appropriate person listed in Table 1 

of this preamble in the preceding FOR

FURTHER INFORMATION CONTACT section. 

Submitting Comments/CBI. Direct 

your comments to Docket ID No. EPA– 

HQ–OAR–2008–0008. If commenting on 

changes to the residual risk and 

technology reviews (RTR) database, 

please submit your comments in the 

format described in sections III and IV 

of this preamble. Do not submit CBI to 

EPA through http://www.regulations.gov 

or e-mail. Instead, send or deliver 

information identified as CBI only to the 

following address: Mr. Roberto Morales, 

OAQPS Document Control Officer 

(C404–02), U.S. Environmental 

Protection Agency, Office of Air Quality 

Planning and Standards, Research 

Triangle Park, NC 27711, Attention 

Docket ID No. EPA–HQ–OAR–2008– 

0008. Clearly mark the part or all of the 

information that you claim to be CBI. 

For CBI information on a disk or CD– 

ROM that you mail to Mr. Morales, mark 

the outside of the disk or CD–ROM as 

CBI and then identify electronically 

within the disk or CD–ROM the specific 

information that is claimed as CBI. 

In addition to one complete version of 

the comment that includes information 

claimed as CBI, a copy of the comment 

that does not contain the information 

claimed as CBI must be submitted for 

inclusion in the public docket. If you 

submit a CD–ROM or disk that does not 

contain CBI, mark the outside of the 

disk or CD–ROM clearly that it does not 

contain CBI. Information not marked as 

CBI will be included in the public 

docket and EPA’s electronic public 

docket without prior notice. 

If you have any questions about CBI 

or the procedures for claiming CBI, 

please consult the person identified in 

the FOR FURTHER INFORMATION CONTACT

section. Information marked as CBI will 

not be disclosed except in accordance 

with procedures set forth in 40 CFR 

part 2. 

Worldwide Web (WWW). In addition 

to being available in the docket, an 

electronic copy of this proposed action 

will also be available on the WWW 

through the Technology Transfer 

Network (TTN). Following signature, a 

copy of the proposed action will be 

posted on the TTN’s policy and 

guidance page for newly proposed or 

promulgated rules at the following 

address: http://www.epa.gov/ttn/oarpg/. 

The TTN provides information and 

technology exchange in various areas of 

air pollution control. 

As discussed in more detail in 

sections III and IV of this preamble, 

additional information is available on 

the RTR Phase II Web page at http:// 

www.epa.gov/ttn/atw/rrisk/rtrpg.html. 

This information includes source 

category descriptions and detailed 

emissions and other data that were used 

as inputs to the risk assessments. 

Public Hearing. If a public hearing is 

held, it will begin at 10 a.m. on 

November 10, 2008 and will be held at 

EPA’s campus in Research Triangle 

Park, North Carolina, or at an alternate 

facility nearby. Persons interested in 

presenting oral testimony or inquiring 

as to whether a public hearing is to be 

held should contact Ms. Mary Tom 

Kissell, Office of Air Quality Planning 

and Standards, Sector Policies and 

Programs Division, Coatings and 

Chemicals Group (E143–01), U.S. 

Environmental Protection Agency, 

Research Triangle Park, NC 27711; 

telephone number: (919) 541–4516. 

Outline. The information presented in 

this preamble is organized as follows: 

I. Background 

A. What is the statutory authority for this 

action? 

B. Overview of RTR 

C. Overview of the Five NESHAP 

D. How did we estimate risk posed by the 

nine source categories? 


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60434 Federal Register / Vol. 73, No. 198 / Friday, October 10, 2008 / Proposed Rules 

1 ‘‘Adverse environmental effect’’ is defined in 

CAA section 112(a)(7) as any significant and 

widespread adverse effect, which may be 

reasonably anticipated to wildlife, aquatic life, or 

natural resources, including adverse impacts on 

populations of endangered or threatened species or 

significant degradation of environmental qualities 

over broad areas. 

E. What are the results of the risk 

assessment? 

F. What are our proposed decisions on 

acceptability and ample margin of 

safety? 

G. What are the results of the technology 

review? 

II. Proposed Action 

A. What is the rationale for our proposed 

action under CAA section 112(f)? 

B. What is the rationale for our proposed 

action under CAA section 112(d)(6)? 

III. Request for Comments 

IV. How do I submit suggested data 

corrections? 

V. Statutory and Executive Order Reviews 

A. Executive Order 12866: Regulatory 

Planning and Review 

B. Paperwork Reduction Act 

C. Regulatory Flexibility Act 

D. Unfunded Mandates Reform Act 

E. Executive Order 13132: Federalism 

F. Executive Order 13175: Consultation 

and Coordination with Indian Tribal 

Governments 

G. Executive Order 13045: Protection of 

Children from Environmental Health 

Risks and Safety Risks 

H. Executive Order 13211: Actions 

Concerning Regulations That 

Significantly Affect Energy Supply, 

Distribution, or Use 

I. National Technology Transfer and 

Advancement Act 

J. Executive Order 12898: Federal Actions 

to Address Environmental Justice in 

Minority Populations and Low-Income 

Populations 

I. Background 

A. What is the statutory authority for 

this action? 

Section 112 of the CAA establishes a 

two-stage regulatory process to address 

emissions of hazardous air pollutants 

(HAP) from stationary sources. In the 

first stage, after EPA has identified 

categories of sources emitting one or 

more of the HAP listed in section 112(b) 

of the CAA, section 112(d) of the CAA 

calls for us to promulgate NESHAP for 

those sources. ‘‘Major sources’’ are those 

that emit or have the potential to emit 

any single HAP at a rate of 10 tons or 

more per year of a single HAP or 25 tons 

per year of any combination of HAP. For 

major sources, these technology-based 

standards must reflect the maximum 

degree of emission reductions of HAP 

achievable (after considering cost, 

energy requirements, and non-air 

quality health and environmental 

impacts) and are commonly referred to 

as maximum achievable control 

technology (MACT) standards. 

The MACT ‘‘floor’’ is the minimum 

control level allowed for MACT 

standards promulgated under section 

112(d)(3). For new sources, the MACT 

floor cannot be less stringent than the 

emission control that is achieved in 

practice by the best-controlled similar 

source. The MACT standards for 

existing sources can be less stringent 

than standards for new sources, but they 

cannot be less stringent than the average 

emission limitation achieved by the 

best-performing 12 percent of existing 

sources in the category or subcategory 

(or the best-performing five sources for 

categories or subcategories with fewer 

than 30 sources). In developing MACT 

standards, we must also consider 

control options that are more stringent 

than the floor. We may establish 

standards more stringent than the floor 

based on the consideration of the cost of 

achieving the emissions reductions, any 

non-air quality health and 

environmental impacts, and energy 

requirements. 

EPA is then required to review these 

technology-based standards and to 

revise them ‘‘as necessary (taking into 

account developments in practices, 

processes, and control technologies)’’ no 

less frequently than every 8 years, under 

CAA section 112(d)(6). In this proposed 

rule, we are publishing the results of our 

8-year technology review for the nine 

industrial source categories listed in 

Table 3, which we have collectively 

termed ‘‘Group 2A.’’ 

The second stage in standard-setting 

focuses on reducing any remaining 

‘‘residual’’ risk according to CAA 

section 112(f). This provision requires, 

first, that EPA prepare a Report to 

Congress discussing (among other 

things) methods of calculating risk 

posed (or potentially posed) by sources 

after implementation of the MACT 

standards, the public health significance 

of those risks, the means and costs of 

controlling them, actual health effects to 

persons in proximity of emitting 

sources, and recommendations as to 

legislation regarding such remaining 

risk. EPA prepared and submitted this 

report (Residual Risk Report to 

Congress, EPA–453/R–99–001) in March 

1999. Congress did not act in response 

to the report, thereby triggering EPA’s 

obligation under CAA section 112(f)(2) 

to analyze and address residual risk. 

CAA section 112(f)(2) requires us to 

determine for source categories subject 

to certain CAA section 112(d) standards 

whether the emissions limitations 

provide an ample margin of safety to 

protect public health. If the MACT 

standards for HAP ‘‘classified as a 

known, probable, or possible human 

carcinogen do not reduce lifetime excess 

cancer risks to the individual most 

exposed to emissions from a source in 

the category or subcategory to less than 

1-in-1 million,’’ EPA must promulgate 

residual risk standards for the source 

category (or subcategory) as necessary to 

provide an ample margin of safety to 

protect public health. In doing so, EPA 

may adopt standards equal to existing 

MACT standards (NRDC v. EPA, No. 

07–1053, slip op. at 11, D.C. Cir., 

decided June 6, 2008). EPA must also 

adopt more stringent standards, if 

necessary, to prevent an adverse 

environmental effect,1 but must 

consider cost, energy, safety, and other 

relevant factors in doing so. Section 

112(f)(2) of the CAA expressly preserves 

our use of a two-step process for 

developing standards to address any 

residual risk and our interpretation of 

‘‘ample margin of safety’’ developed in 

the National Emission Standards for 

Hazardous Air Pollutants: Benzene 

Emissions from Maleic Anhydride 

Plants, Ethylbenzene/Styrene Plants, 

Benzene Storage Vessels, Benzene 

Equipment Leaks, and Coke By-Product 

Recovery Plants (Benzene NESHAP) 

(54 FR 38044, September 14, 1989). 

The first step in this process is the 

determination of acceptable risk. The 

second step provides for an ample 

margin of safety to protect public health, 

which is the level at which the 

standards are set (unless a more 

stringent standard is required to 

prevent, taking into consideration costs, 

energy, safety, and other relevant 

factors, an adverse environmental 

effect). 

The terms ‘‘individual most exposed,’’ 

‘‘acceptable level,’’ and ‘‘ample margin 

of safety’’ are not specifically defined in 

the CAA. However, CAA section 

112(f)(2)(B) directs us to use the 

interpretation set out in the Benzene 

NESHAP. See also, A Legislative History 

of the Clean Air Act Amendments of 

1990, volume 1, p. 877 (Senate debate 

on Conference Report). We notified 

Congress in the Residual Risk Report to 

Congress that we intended to use the 

Benzene NESHAP approach in making 

CAA section 112(f) residual risk 

determinations (EPA–453/R–99–001, p. 

ES–11). 

In the Benzene NESHAP, we stated as 

an overall objective: 

* * * in protecting public health with an 

ample margin of safety, we strive to provide 

maximum feasible protection against risks to 

health from hazardous air pollutants by (1) 

protecting the greatest number of persons 

possible to an individual lifetime risk level 

no higher than approximately 1-in-1 million; 

and (2) limiting to no higher than 

approximately 1-in-10 thousand [i.e., 100-in1 million] the estimated risk that a person 


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Federal Register / Vol. 73, No. 198 / Friday, October 10, 2008 / Proposed Rules 60435 

living near a facility would have if he or she 

were exposed to the maximum pollutant 

concentrations for 70 years. 

The Agency also stated that, ‘‘The 

EPA also considers incidence (the 

number of persons estimated to suffer 

cancer or other serious health effects as 

a result of exposure to a pollutant) to be 

an important measure of the health risk 

to the exposed population. Incidence 

measures the extent of health risk to the 

exposed population as a whole, by 

providing an estimate of the occurrence 

of cancer or other serious health effects 

in the exposed population.’’ The Agency 

went on to conclude that ‘‘estimated 

incidence would be weighed along with 

other health risk information in judging 

acceptability.’’ As explained more fully 

in our Residual Risk Report to Congress, 

EPA does not define ‘‘rigid line[s] of 

acceptability,’’ but considers rather 

broad objectives to be weighed with a 

series of other health measures and 

factors (EPA–453/R–99–001, p. ES–11). 

The determination of what represents an 

‘‘acceptable’’ risk is based on a 

judgment of ‘‘what risks are acceptable 

in the world in which we live’’ 

(Residual Risk Report to Congress, p. 

178, quoting the Vinyl Chloride decision 

at 824 F.2d 1165) recognizing that our 

world is not risk-free. 

In the Benzene NESHAP, we stated 

that ‘‘EPA will generally presume that if 

the risk to [the maximum exposed] 

individual is no higher than 

approximately 1 in 10 thousand, that 

risk level is considered acceptable.’’ 54 

FR at 38045. We discussed the 

maximum individual lifetime cancer 

risk as being ‘‘the estimated risk that a 

person living near a plant would have 

if he or she were exposed to the 

maximum pollutant concentrations for 

70 years.’’ Id. We explained that this 

measure of risk ‘‘is an estimate of the 

upperbound of risk based on 

conservative assumptions, such as 

continuous exposure for 24 hours per 

day for 70 years.’’ Id. We acknowledge 

that maximum individual lifetime 

cancer risk ‘‘does not necessarily reflect 

the true risk, but displays a conservative 

risk level which is an upperbound that 

is unlikely to be exceeded.’’ Id. 

Understanding that there are both 

benefits and limitations to using 

maximum individual lifetime cancer 

risk as a metric for determining 

acceptability, we acknowledged in the 

1989 Benzene NESHAP that 

‘‘consideration of maximum individual 

risk * * * must take into account the 

strengths and weaknesses of this 

measure of risk.’’ Id. Consequently, the 

presumptive risk level of 100-in-1 

million (1-in-10 thousand) provides a 

benchmark for judging the acceptability 

of maximum individual lifetime cancer 

risk, but does not constitute a rigid line 

for making that determination. 

The Agency also explained in the 

1989 Benzene NESHAP the following: 

‘‘In establishing a presumption for MIR 

[maximum individual cancer risk], 

rather than rigid line for acceptability, 

the Agency intends to weigh it with a 

series of other health measures and 

factors. These include the overall 

incidence of cancer or other serious 

health effects within the exposed 

population, the numbers of persons 

exposed within each individual lifetime 

risk range and associated incidence 

within, typically, a 50 kilometer (km) 

exposure radius around facilities, the 

science policy assumptions and 

estimation uncertainties associated with 

the risk measures, weight of the 

scientific evidence for human health 

effects, other quantified or unquantified 

health effects, effects due to co-location 

of facilities, and co-emission of 

pollutants.’’ Id. 

In some cases, these health measures 

and factors taken together may provide 

a more realistic description of the 

magnitude of risk in the exposed 

population than that provided by 

maximum individual lifetime cancer 

risk alone. 

As explained in the Benzene 

NESHAP, ‘‘[e]ven though the risks 

judged ‘‘acceptable’’ by EPA in the first 

step of the Vinyl Chloride inquiry are 

already low, the second step of the 

inquiry, determining an ‘‘ample margin 

of safety,’’ again includes consideration 

of all of the health factors, and whether 

to reduce the risks even further. In the 

second step, EPA strives to provide 

protection to the greatest number of 

persons possible to an individual 

lifetime risk level no higher than 

approximately 1 in 1 million. In the 

ample margin decision, the Agency 

again considers all of the health risk and 

other health information considered in 

the first step. Beyond that information, 

additional factors relating to the 

appropriate level of control will also be 

considered, including costs and 

economic impacts of controls, 

technological feasibility, uncertainties, 

and any other relevant factors. 

Considering all of these factors, the 

Agency will establish the standard at a 

level that provides an ample margin of 

safety to protect the public health, as 

required by section 112.’’ 54 FR at 

38046. 

B. Overview of RTR 

We have begun to conduct the RTR 

for 96 MACT standards covering 174 

sources categories. In an effort to 

streamline the RTR process and focus 

our resources on source categories with 

the greatest potential for risk to human 

health and the environment, we 

combined source categories to create 

several groups, e.g., RTR Group 2A 

(which is the subject of this proposed 

rule), and decided the order in which 

we would propose each source category 

group. In deciding how to group source 

categories, we considered factors such 

as the promulgation date of the 

NESHAP, our preliminary analysis of 

the level of risk, completeness of 

available emissions data, complexity of 

the risk assessment, and whether we 

anticipated promulgating additional 

regulations pursuant to the RTR. 

In general, we are addressing source 

categories with the earliest NESHAP 

promulgation dates first because they 

have the earliest RTR due dates and 

because the 2002 National Emission 

Inventory (NEI) contains emissions data 

which reflect implementation of the 

NESHAP. Additionally, we are 

addressing lower risk source categories 

first because they typically require less 

effort to complete the necessary analysis 

than higher risk source categories. We 

expect that the higher risk source 

categories will require more time to 

evaluate because we will likely need to 

perform more refined risk assessments, 

and because they may have more 

complex issues to address, such as the 

emissions of persistent and 

bioaccumulative HAP. Moreover, we 

believe our reviews of the higher risk 

source categories will benefit from an 

understanding of the public’s concerns 

about our RTR approaches (through the 

comments we receive on the earlier 

proposals). 

For the nine source categories in 

today’s proposal for RTR Group 2A, we 

have concluded that emissions levels 

remaining after compliance with the 

existing MACT standards: (1) Pose no 

unacceptable maximum individual 

cancer risks (i.e., because the MIR is less 

than 100-in-1 million the risk is 

acceptable); (2) pose no significant 

chronic noncancer health effects (i.e., 

maximum individual target organspecific hazard index (HI) values are all 

less than or equal to 1); (3) are unlikely 

to result in acute adverse health effects 

from peak short-term excursions; and (4) 

are unlikely to result in any adverse 

environmental effect. Thus, we are 

proposing that the existing standards 

provide an ample margin of safety to 

protect public health and prevent 

adverse environmental effects. 

Future RTR actions for other source 

categories may require changes to 

existing MACT standards to achieve the 

protection of public health with an 

ample margin of safety and/or to 


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60436 Federal Register / Vol. 73, No. 198 / Friday, October 10, 2008 / Proposed Rules 

2RTR Group 2B: Oil and Natural Gas Production; 

Natural Gas Transmission; and Aerospace 

Operations. RTR Group 2C: Primary Aluminum; Polymers and Resins IV (seven source categories); 

and Ship Building. 

prevent adverse environmental effects. 

Future actions may also require 

additional emission reductions pursuant 

to the technology review. We plan to 

conduct RTR assessments for 12 source 

categories (RTR Groups 2B and 2C, 

which were included in an advanced 

notice of proposed rulemaking in March 

2007) and propose our findings.2 In 

addition, we plan to publish at least 

three more advanced notices of 

proposed rulemaking. We may also 

publish some RTR for individual MACT 

standards because of special 

circumstances such as court ordered 

deadlines. (See, for example, the 

proposed RTR for Petroleum Refineries, 

72 FR 50716, 09/04/2007.) 

C. Overview of the Five NESHAP 

The nine industrial source categories 

and five NESHAP that are the subject of 

this proposal are listed in Table 3 to this 

preamble. NESHAP limit and control 

HAP that are known or suspected to 

cause cancer or that may cause other 

serious human health or environmental 

effects. The NESHAP for these nine 

source categories generally require 

implementation of emissions reduction 

technologies such as combustion 

devices, recovery devices, scrubbers, 

and fabric filters for point sources and 

work practice and equipment standards 

for fugitive sources. 

TABLE 3—LIST OF NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS (NESHAP) AND INDUSTRIAL

SOURCE CATEGORIES AFFECTED BY TODAY’S PROPOSAL

Title of NESHAP Source categories affected by 

this proposal Promulgated rule reference Compliance date 

NESHAP as referred to in this 

preamble 

NESHAP: Group I Polymers 

and Resins 1.

Epichlorohydrin Elastomers 

Production Hypalon TM Production.

61 FR 46905 (09/05/96) ......... 07/31/97 Polymers and Resins I. 

Nitrile Butadiene Rubber Production.

Polybutadiene Rubber Production.

Styrene-Butadiene Rubber 

and Latex Production.

National Emission Standards 

for Marine Vessel Loading 

Operations.

Marine Vessel Loading Operations.60 FR 48388 (09/19/95) ......... 09/19/99 Marine Vessels. 

NESHAP for Mineral Wool 

Production.

Mineral Wool Production ........ 64 FR 29489 (06/01/99) ......... 06/01/02 Mineral Wool. 

National Emission Standards 

for Pharmaceuticals Production.

Pharmaceuticals Production ... 63 FR 50280 (09/21/98) ......... 09/21/01 Pharmaceuticals. 

National Emission Standards 

for the Printing and Publishing Industry.

Printing/Publishing (Surface 

Coating).

61 FR 27131 (05/30/96) ......... 05/30/99 Printing and Publishing. 

1The Polymers and Resins I NESHAP regulates nine source categories. We are performing the RTR for five of these in this proposal. The four 

other Polymers and Resins I source categories are being addressed in a separate RTR rulemaking. (See National Emission Standards for Hazardous Air Pollutant Emissions: Group I Polymers and Resins (Polysulfide Rubber Production, Ethylene Propylene Rubber Production, Butyl Rubber Production, Neoprene Production); National Emission Standards for Hazardous Air Pollutants for Epoxy Resins Production and Non-Nylon 

Polyamides Production; National Emission Standards for Hazardous Air Pollutants for Source Categories: Generic Maximum Achievable Control 

Technology Standards (Acetal Resins Production and Hydrogen Fluoride Production), proposed on December 12, 2007, at 72 FR 70543.) 

1. Polymers and Resins I 

The National Emission Standards for 

Hazardous Air Pollutant Emissions: 

Group I Polymers and Resins were 

promulgated on September 5, 1996 (62 

FR 46925). The Polymers and Resins I 

NESHAP applies to major sources and 

regulates HAP emissions from nine 

source categories. In this proposal, we 

address five of the Polymer and Resins 

I sources categories—Epichlorohydrin 

Elastomers Production, Hypalon TM

Production, Nitrile Butadiene Rubber 

Production, Polybutadiene Rubber 

Production, and Styrene Butadiene 

Rubber and Latex Production. 

The Polymers and Resins I NESHAP 

regulate HAP emissions resulting from 

the production of elastomers (i.e., 

synthetic rubber). An elastomer is a 

synthetic polymeric material that can 

stretch at least twice its original length 

and then return rapidly to 

approximately its original length when 

released. Elastomers are produced via a 

polymerization/copolymerization 

process, in which monomers undergo 

intermolecular chemical bond formation 

to form a very large polymer molecule. 

Generally, the production of elastomers 

entails four processes: (1) Raw material 

(i.e., solvent) storage and refining; (2) 

polymer formation in a reactor (either 

via the solution process, where 

monomers are dissolved in an organic 

solvent, or the emulsion process, where 

monomers are dispersed in water using 

a soap solution); (3) stripping and 

material recovery; and (4) finishing (i.e., 

blending, aging, coagulation, washing, 

and drying). 

Sources of HAP emissions from 

elastomers production include raw 

material storage vessels, front-end 

process vents, back-end process 

operations, wastewater operations, and 

equipment leaks. The ‘‘front-end’’ 

processes include pre-polymerization, 

reaction, stripping, and material 

recovery operations; and the process 

‘‘back-end’’ includes all operations after 

stripping (predominately drying and 

finishing). Typical control devices used 

to reduce organic HAP emissions from 

front-end process vents include flares, 

incinerators, absorbers, carbon 

adsorbers, and condensers. In addition, 

hydrochloric acid formed when 

chlorinated organic compounds are 

combusted are controlled using 

scrubbers. Emissions from storage 

vessels are controlled by floating roofs 

or by routing them to a control device. 

While emissions from back-end process 

operations can be controlled with 


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3Our analysis of the impacts of the worst case 

MACT allowable emissions as compared to reported 

actual emissions for each of the nine source 

categories is discussed in more detail in 

‘‘Estimation of MACT Allowable Emission Levels 

and Associated Risks and Impacts for the RTR 

Group 2A Source Categories.’’. 

control devices such as incinerators, the 

most common method of reducing these 

emissions is the pollution prevention 

method of reducing the amount of 

residual HAP that is contained in the 

raw product going to the back-end 

operations. Emissions from wastewater 

are controlled by a variety of methods, 

including equipment modifications 

(e.g., fixed roofs on storage vessels and 

oil water separators; covers on surface 

impoundments, containers, and drain 

systems), treatment to remove the HAP 

(steam stripping, biological treatment), 

control devices, and work practices. 

Emissions from equipment leaks are 

typically reduced by leak detection and 

repair work practice programs, and in 

some cases, by equipment 

modifications. 

Each of the five Polymers and Resins 

I source categories addressed in this 

proposal are discussed further below. 

a. Epichlorohydrin Elastomers 

Production 

Epichlorohydrin elastomers are 

prepared from the polymerization or 

copolymerization of epichlorohydrin or 

other monomers. Epichlorohydrin 

elastomers are produced by a solution 

polymerization process, typically using 

toluene as the solvent in the reaction. 

The main epichlorohydrin elastomers 

are polyepichlorohydrin, epi-ethylene 

oxide (EO) copolymer, epi-allyl glycidyl 

ether (AGE) copolymer, and epi-EOAGE terpolymer. Epichlorohydrin 

elastomers are widely used in the 

automotive industry. 

We identified one epichlorohydrin 

elastomers production facility currently 

subject to the Polymers and Resins I 

NESHAP. This facility produces 

epichlorohydrin elastomers primarily, 

but the plant site also has equipment 

regulated by other NESHAP, which have 

been or will be addressed in separate 

RTR rulemaking actions. 

Toluene accounts for the majority of 

the HAP emissions from the 

epichlorohydrin production processes at 

this facility (approximately 105 tons per 

year (TPY) and 99 percent of the total 

HAP emissions by mass). This facility 

also reported relatively small emissions 

of epichlorohydrin and ethylene oxide. 

The majority of HAP emissions are from 

back-end process vents (approximately 

75 percent of the total HAP by mass). 

We estimate that the MACT allowable 

emissions (i.e., the maximum emission 

levels allowed if in compliance with the 

NESHAP) from this source category are 

approximately equal to the reported, 

actual emissions.3

b. Hypalon TM Production 

Hypalon,TM or chlorosulfonated 

polyethylene, is a synthetic rubber 

produced by reacting polyethylene with 

chlorine and sulfur dioxide, 

transforming the thermoplastic 

polyethylene into a vulcanized 

elastomer. The reaction is conducted in 

a solvent reaction medium containing 

carbon tetrachloride. These elastomers 

are commonly used in wire insulation 

and jacketing, automotive components, 

adhesives, and protective coatings. 

We identified one Hypalon TM

production facility currently subject to 

the Polymers and Resins I NESHAP. The 

plant site for this facility also has other 

HAP-emitting sources which are 

regulated under separate NESHAP, 

including Marine Vessel Loading 

Operations, 40 CFR part 63, subpart Y. 

Marine Vessel Loading Operations are 

addressed separately in this proposed 

rule, but RTR for the other NESHAP 

have been or will be addressed in 

separate rulemaking actions. 

Carbon tetrachloride accounts for the 

majority of the HAP emissions from the 

Hypalon TM production processes at this 

facility (approximately 22 TPY and 71 

percent of the total HAP emissions by 

mass). This facility also reported 

relatively small emissions of chlorine, 

chloroform, and hydrochloric acid. The 

majority of HAP emissions are from 

front-end process vents (approximately 

63 percent of the total HAP by mass) 

and back-end process operations 

(approximately 33 percent of the total 

HAP by mass). We estimate that MACT 

allowable emissions from this source 

category are approximately equal to 

reported, actual emissions. 

c. Nitrile Butadiene Rubber Production 

Nitrile butadiene rubber (NBR) is a 

copolymer of 1,3-butadiene and 

acrylonitrile, and the NBR production 

source category includes any facility 

that polymerizes 1,3-butadiene and 

acrylonitrile. While NBR is the primary 

product at these facilities, styrenebutadiene rubber can also be produced 

as a minor product by substituting 

styrene for acrylonitrile as a monomer. 

Depending on its specific composition, 

NBR can be resistant to oil and 

chemicals, a property that facilitates its 

use in disposable gloves, hoses, seals, 

and a variety of automotive 

applications. 

We identified four NBR production 

facilities currently subject to the 

Polymers and Resins I NESHAP. Two of 

these facilities are at plant sites that also 

have operations which produce styrenebutadiene rubber and latex, another 

Polymers and Resins I source category. 

The styrene-butadiene rubber and latex 

processes and emissions are addressed 

separately in today’s proposed action 

under the Styrene Butadiene Rubber 

and Latex source category. Some of 

these facilities also have other HAPemitting sources that are regulated 

under separate NESHAP, which have 

been or will be addressed in separate 

RTR rulemaking actions. 

Styrene, 1,3-butadiene, and 

acrylonitrile account for the majority of 

the HAP emissions from this source 

category (approximately 46 TPY and 

over 99 percent of the total HAP 

emissions by mass). The facilities in this 

source category also reported relatively 

small emissions of carbon disulfide. The 

majority of HAP emissions are from 

back-end process operations 

(approximately 43 percent of the total 

HAP by mass) and front-end process 

vents (approximately 34 percent of the 

total HAP by mass) for this source 

category. However, the emissions from 

one facility were not included in this 

estimation of emissions by source type, 

as it was not possible to positively 

discern which types of emission sources 

were responsible for emissions from this 

facility in all instances. Based on the 

emissions release characteristics for this 

facility, we estimate that of the facility’s 

48 TPY of HAP emissions, the majority 

are from back-end process operations 

and equipment leaks (approximately 58 

and 23 percent by mass, respectively). 

We estimate that MACT allowable 

emissions from this source category are 

approximately equal to reported, actual 

emissions. 

d. Polybutadiene Rubber Production 

Polybutadiene rubber (PBR) is a 

homopolymer of 1,3-butadiene (i.e., 1,3- 

butadiene is the only monomer used in 

the production of this polymer). While 

both the solution and emulsion 

polymerization processes can be used to 

produce PBR, all currently operating 

facilities in the United States use a 

solution process. In the solution 

process, the reaction is conducted in an 

organic solvent (hexane, toluene, or a 

non-HAP organic solvent), which helps 

to dissipate heat generated by the 

reaction and control the reaction rate. 

While PBR is the primary product at 

these facilities, styrene-butadiene rubber 

can also be produced as a minor product 

by adding styrene as a monomer. Most 

of the PBR manufactured in the United 

States is used in the production of tires 

in the construction of the tread and 


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sidewalls. PBR is also used as a modifier 

in the production of other polymers and 

resins (e.g., polystyrene). 

We identified five PBR production 

facilities currently subject to the 

Polymers and Resins I NESHAP. Some 

of these facilities are located at plant 

sites that also have other HAP-emitting 

sources regulated under separate 

NESHAP, which have been or will be 

addressed in separate RTR actions. 

Three of the PBR production facilities 

use hexane as the solvent in their 

solution process, one facility uses 

toluene as its solvent, and the fifth uses 

a non-HAP organic solvent. Overall, 

hexane accounts for the majority of the 

HAP emissions from this source 

category (approximately 1,455 TPY and 

72 percent of the total HAP emissions 

by mass). The facilities in this source 

category also reported substantive 

emissions of styrene and 1,3-butadiene 

and relatively minor quantities of three 

other HAP. The majority of HAP 

emissions are from back-end process 

operations (approximately 73 percent of 

the total HAP by mass). We estimate 

that MACT allowable emissions from 

this source category could be as high as 

five times the actual emissions. 

e. Styrene Butadiene Rubber and Latex 

Production 

Styrene butadiene rubber and latex 

are elastomers prepared from styrene 

and butadiene monomer units. The 

source category is divided into three 

subcategories due to technical process 

and HAP emission differences: (1) The 

production of styrene butadiene rubber 

by emulsion, (2) the production of 

styrene butadiene rubber by solution, 

and (3) the production of styrene 

butadiene latex. Styrene butadiene 

rubber is coagulated and dried to 

produce a solid product, while latex is 

a liquid product. For both styrene 

butadiene rubber processes, the 

monomers used are styrene and 

butadiene; either process can be 

conducted as a batch or a continuous 

process. These elastomers are 

commonly used in tires and tire-related 

products. 

We identified two styrene butadiene 

rubber production facilities using the 

emulsion process and 12 styrene 

butadiene rubber latex production 

facilities currently subject to the 

Polymers and Resins I NESHAP. Other 

than the polybutadiene plants that 

produce styrene butadiene rubber as a 

minor product, we did not identify any 

styrene butadiene rubber produced in a 

solution process. Two of these facilities 

are located at plant sites that also have 

operations which produce NBR, another 

Polymers and Resins I source category. 

The NBR processes and emissions are 

addressed separately in this proposed 

action under the Nitrile Butadiene 

Rubber source category. Some of these 

facilities are located at plant sites that 

also have other HAP-emitting sources 

regulated under separate NESHAP, 

which have been or will be addressed in 

separate RTR actions. 

Overall, styrene accounts for the 

majority of the HAP emissions from 

these facilities (approximately 276 TPY 

and 90 percent of the total HAP 

emissions by mass). These facilities also 

reported relatively small emissions of 13 

other HAP. The majority of HAP 

emissions are from back-end process 

operations (approximately 80 percent of 

the total HAP by mass). We estimate 

that MACT allowable emissions from 

this source category could be as high as 

four times the actual emissions. 

2. Marine Vessels 

The National Emission Standards for 

Marine Vessel Loading Operations were 

promulgated on September 19, 1995 (60 

FR 48388). The Marine Vessel Loading 

Operations NESHAP applies to major 

sources and regulates HAP emissions 

from: Land-based terminals, off-shore 

terminals, and the Alyeska Pipeline 

Service Company’s Valdez Marine 

Terminal. 

Marine vessel loading operations are 

facilities that load and unload liquid 

commodities in bulk, such as crude oil, 

gasoline, and other fuels, and some 

chemicals and solvent mixtures. The 

cargo is pumped from the terminal’s 

large, above-ground storage tanks 

through a network of pipes and into a 

storage compartment (tank) on the 

vessel. Emissions occur as vapors are 

displaced from the tank as it is being 

filled. Most marine tank vessel loading 

operations are associated with 

petroleum refineries, synthetic organic 

chemical manufacturers, or are 

independent terminals. 

The primary emission sources of 

displaced vapors at marine vessel 

loading operations include open tank 

hatches and overhead vent systems. 

Other possible emission points are 

hatch covers or domes, pressurevacuum relief valves, seals, and vents. 

Emissions may also occur during 

ballasting (i.e., the process of drawing 

ballast as water into a cargo hold). The 

NESHAP requires control of all 

displaced vapors that occur during 

product loading. Typical control devices 

used to reduce HAP emissions include 

vapor collection systems routed to 

combustion or recovery devices, such as 

flares, incinerators, absorbers, carbon 

adsorbers, and condensers. 

Additional data indicate that 

approximately 800 terminals load HAPcontaining organic liquids. An unknown 

fraction of these are containerized 

liquids that are not subject to the Marine 

Vessel Loading Operations NESHAP. 

Therefore, we estimate up to 800 

facilities may be subject to the Marine 

Vessel Loading Operations NESHAP. 

However, data in the 2002 NEI were 

available for only 135 facilities and our 

analyses are based on these 135 

modeled facilities. We believe the 135 

modeled facilities are representative of 

the source category because we expect 

that generally the same HAP, in the 

same range of quantities, are emitted 

from the 135 modeled facilities as are 

emitted from rest of the facilities in the 

source category. We extrapolated the 

risk results for the 135 modeled 

facilities up to the approximately 800 

facilities in the source category and 

believe the resulting cancer and 

noncancer risks either represent or 

overstate risk from the 800 facilities in 

source category. However, we request 

comment on this approach, additional 

data on pollutant-specific emissions 

from facilities in the NEI, and 

identification of emissions from marine 

vessel loading facilities not included in 

the NEI. 

Marine terminals that are part of the 

petroleum refineries source category are 

not regulated by the Marine Vessel 

Loading Operations NESHAP. 

Therefore, marine terminals that are part 

of the petroleum refineries source 

category were not included in this risk 

assessment. The petroleum refineries 

marine terminals are being addressed in 

a separate RTR rulemaking action. (See 

the proposed RTR for Petroleum 

Refineries, 72 FR 50716, 09/04/2007.) 

Hexane, methanol, toluene, and 

mixed xylenes account for the majority 

of the HAP emissions from the 135 NEI 

facilities (approximately 184 TPY and 

73 percent of the total HAP emissions 

by mass). These facilities also reported 

relatively small emissions of 42 other 

HAP. These emissions are from the 

loading operations at the terminals. 

MACT allowable emission levels from 

this source category could be higher 

than actual emission levels due 

primarily to states requiring controls 

(typically 90 percent reduction) for 

some marine terminals that are not 

controlled by the Marine Vessel Loading 

Operations NESHAP. Based on typical 

state rule emission reduction 

requirements we estimate that the 

MACT allowable emissions from this 

source category would be 10 times the 

actual emissions for terminals not 

controlled by the Marine Vessel Loading 

Operations NESHAP and approximately 


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two times the actual emissions for 

marine terminals that are controlled by 

the Marine Vessel Loading Operations 

NESHAP. 

3. Mineral Wool Production 

The National Emission Standards for 

Mineral Wool Production were 

promulgated on June 1, 1999 (64 FR 

29489). The Mineral Wool Production 

NESHAP applies to major sources of 

HAP. 

Mineral wool is a fibrous, glassy 

substance made from natural rock (such 

as basalt), blast furnace slag, or other 

similar materials. In the mineral wool 

manufacturing process, rock and/or 

blast furnace slag and other raw 

materials (e.g., gravel) are melted in a 

furnace (cupola) using coke as a fuel. 

The molten material is then formed into 

fiber. Mineral wool is manufactured as 

either a ‘‘bonded’’ product that 

incorporates a binder to increase 

structural rigidity or a less rigid 

‘‘nonbonded’’ product. Products made 

from mineral wool are used for 

insulation, sound control and 

attenuation, and fire protection. The 

industry is declining significantly due 

to economic and competitive reasons 

(e.g., availability of alternative products 

such as cellulose insulation). 

Emission sources at mineral wool 

production facilities include the cupola 

furnace where the mineral charge is 

melted; a blow chamber, in which air or 

a binder is drawn over the fibers, 

forming them into a screen; a curing 

oven that bonds the fibers (for bonded 

products); and a cooling chamber. The 

majority of the emissions originate from 

the cupolas and curing ovens. The 

NESHAP requires control of particulate 

matter emissions from the cupolas and 

formaldehyde emissions from the curing 

ovens. Typical control devices used to 

reduce HAP emissions from the cupola 

include baghouses/fabric filters, and 

emissions from the curing ovens are 

generally controlled with thermal 

incinerators. 

We identified eight facilities currently 

subject to the Mineral Wool Production 

NESHAP. Some of these facilities also 

have other HAP-emitting sources that 

are regulated under separate NESHAP, 

which have been or will be addressed in 

separate RTR rulemaking actions. 

Carbonyl sulfide accounts for the 

majority of the HAP emissions from 

these facilities (approximately 416 TPY 

and 87 percent of the total HAP 

emissions by mass). These facilities also 

reported relatively small emissions of 16 

other HAP. The majority of HAP 

emissions are from the cupolas 

(approximately 80 percent of the total 

HAP by mass). The majority of HAP 

emissions (primarily formaldehyde) that 

were significant in evaluating risk are 

from the cooling chambers. We estimate 

that MACT allowable emissions from 

this source category could be as high as 

two times the actual emissions. 

4. Pharmaceuticals Production 

The National Emission Standards for 

Pharmaceuticals Production were 

promulgated on September 21, 1998 (63 

FR 50280). The Pharmaceuticals 

Production NESHAP applies to major 

sources of HAP. 

The pharmaceutical manufacturing 

process consists of chemical production 

operations that produce drugs and 

medication. These operations include 

chemical synthesis (deriving a drug’s 

active ingredient) and chemical 

formulation (producing a drug in its 

final form). 

Emission sources at pharmaceutical 

production facilities include breathing 

and withdrawal losses from chemical 

storage tanks, venting of process vessels, 

leaks from piping and equipment used 

to transfer HAP compounds (equipment 

leaks), and volatilization of HAP from 

wastewater streams. 

Typical control devices used to 

reduce HAP emissions from process 

vents include flares, incinerators, 

scrubbers, carbon adsorbers, and 

condensers. Emissions from storage 

vessels are controlled by floating roofs 

or by routing them to a control device. 

Emissions from wastewater are 

controlled by a variety of methods, 

including equipment modifications 

(e.g., fixed roofs on storage vessels and 

oil water separators; covers on surface 

impoundments containers, and drain 

systems), treatment to remove the HAP 

(steam stripping, biological treatment), 

control devices, and work practices. 

Emissions from equipment leaks are 

typically reduced by leak detection and 

repair work practice programs, and in 

some cases, by equipment 

modifications. 

We identified 27 facilities currently 

subject to the Pharmaceuticals 

Production NESHAP. Some of these 

facilities are located at plant sites that 

also have other HAP-emitting sources 

regulated under separate NESHAP, 

which have been or will be addressed in 

separate rulemaking actions. 

Methylene chloride, methanol, 

acetonitrile, and toluene account for the 

majority of the HAP emissions from 

these facilities (approximately 891 TPY 

and 90 percent of the total HAP 

emissions by mass). These facilities also 

reported relatively small emissions of 65 

other HAP. The majority of HAP 

emissions are from the process vents 

(approximately 70 percent of the total 

HAP by mass emitted from process 

vents, with 20 percent and 10 percent of 

the total HAP by mass emitted from 

equipment leaks and wastewater 

operations, respectively). We estimate 

that MACT allowable emissions from 

this source category could be up to 25 

percent greater than the actual 

emissions, primarily from process vents, 

as it is possible that the control devices 

used at some facilities achieve greater 

emission reductions from these 

emission sources than what is required 

by the NESHAP. 

5. Printing and Publishing Industry 

The National Emission Standards for 

the Printing and Publishing Industry 

were promulgated on May 30, 1996 (61 

FR 27132). The Printing and Publishing 

NESHAP applies to major sources of 

HAP. 

Printing and publishing facilities are 

those facilities that use rotogravure, 

flexography, and other methods, such as 

lithography, letterpress, and screen 

printing, to print on a variety of 

substrates, including paper, plastic film, 

metal foil, and vinyl. The Printing and 

Publishing NESHAP focuses on two 

subcategories: (1) Publication 

rotogravure printing and (2) product and 

packaging rotogravure and wide-web 

flexographic printing. Emissions at 

printing and publishing facilities result 

from the evaporation of solvents in the 

inks and from cleaning solvents. The 

emission points include printing presses 

and associated dryers and ink and 

solvent storage. Control techniques 

include recovery devices, combustion 

devices, and the use of non-HAP/lowHAP inks and cleaning solvents. 

We estimate that approximately 200 

facilities are subject to the Printing and 

Publishing NESHAP based on the 

information we gathered in support of 

the rule development in 1996. As data 

were available for 179 major source 

facilities in the 2002 NEI, our analyses 

are based on these 179 facilities. We 

believe the 179 facilities represent the 

source category because: (1) We have no 

reason to believe that emissions from 

the other facilities are different from the 

facilities we modeled; (2) the difference 

between the number of facilities 

counted in 1996 and 2002 might be 

accounted for by facility closures and by 

some facilities achieving area source 

status for HAP before the first 

compliance date of the Printing and 

Publishing NESHAP; and, (3) we believe 

in most cases data on 90 percent of the 

facilities in a source category will be 

representative of the source category as 

a whole. Some of these facilities are 

located at plant sites that also have 

other HAP-emitting sources regulated 


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under separate NESHAP, which have 

been or will be addressed in separate 

RTR rulemaking actions. 

Toluene accounts for the majority of 

the HAP emissions from these facilities 

(approximately 6,606 TPY or 88 percent 

of the total HAP emissions by mass). 

These facilities also reported relatively 

small emissions of 56 other HAP. These 

emissions are primarily from the 

evaporation of HAP present in the inks 

and other materials applied with 

rotogravure and flexographic processes. 

We estimate that MACT allowable 

emissions from this source category 

could be up to 5 times greater than the 

actual emissions, as it is possible that 

the capture systems and control devices 

used at some facilities achieve greater 

emission reductions than what is 

required by the NESHAP. 

D. How did we estimate risk posed by 

the nine source categories? 

To support the proposed decisions 

presented in today’s notice, EPA 

conducted a risk assessment that 

provided estimates of MIR, maximum 

individual cancer risk distribution 

within the exposed populations, cancer 

incidence, hazard indices for chronic 

exposures to HAP with non-cancer 

health effects, hazard quotients (HQ) for 

acute exposures to HAP with noncancer health effects, and estimates of 

the potential for adverse environmental 

effects. The risk assessment consisted of 

seven primary activities: (1) Establishing 

the nature and magnitude of emissions 

from the source categories, (2) 

identifying the emissions release 

characteristics (e.g., stack parameters), 

(3) conducting dispersion modeling to 

estimate the concentrations of HAP in 

ambient air, (4) estimating long-term 

and short-term inhalation exposures to 

individuals residing within 50 km of the 

modeled sources, (5) estimating 

individual and population-level 

inhalation risks using the exposure 

estimates and quantitative doseresponse information, (6) estimating the 

potential for adverse human health 

multipathway risks and for adverse 

environmental effects, and (7) 

characterizing risk. In general, the risk 

assessment followed a tiered, iterative 

approach, beginning with a conservative 

(worst case) screening-level analysis 

and, where the screening analyses 

indicated the potential for nonnegligible risks, following that with 

more refined analyses. The following 

sections summarize these activities. For 

more information on the risk assessment 

inputs and models, see ‘‘Residual Risk 

Assessment for Nine Source 

Categories,’’ available in the docket. 

We engaged in a consultation with a 

panel from the Science Advisory Board 

(SAB) on the ‘‘Risk and Technology 

Review (RTR) Assessment Plan’’ in 

December of 2006. The results of this 

consultation were transmitted to us in 

June 2007 in a letter from the SAB 

which also contained a summary listing 

of the key messages from the panel. The 

letter is available from the docket and 

from http://yosemite.epa.gov/sab/sab

product.nsf/33152C83D29

530F08525730D006C3ABF/$File/sab07–009.pdf. In developing the risk 

assessments for the nine source 

categories covered by this proposal, we 

followed the RTR Assessment Plan, 

addressing the key messages from the 

panel, where appropriate and relevant 

to these assessments. 

1. Emissions and Emissions Release 

Characteristic Data 

The basic approach taken to obtain 

the most accurate and reliable emissions 

and emissions release characteristic data 

was to compile preliminary data sets 

using readily available information for 

each source category and to share these 

data with the public via an Advanced 

Notice of Proposed Rulemaking 

(ANPRM). The data sets were then 

updated based on comments received 

on the ANPRM and, in some cases, with 

additional information gathered by EPA. 

For the five Polymers and Resins I 

source categories (Epichlorohydrin 

Elastomers Production, HypalonTM 

Production, Nitrile Butadiene Rubber 

Production, Polybutadiene Rubber 

Production, and Styrene Butadiene 

Rubber and Latex Production), we 

collected emissions data and emissions 

release characteristic data directly from 

industry. These data generally formed 

the data sets used in our analyses for 

these source categories. 

For the remaining four source 

categories (Marine Vessel Loading, 

Mineral Wool, Pharmaceuticals, and 

Printing and Publishing), we created the 

preliminary data sets using the data in 

the 2002 NEI Final Inventory, Version 1 

(made publicly available on February 

26, 2006) supplemented by data 

collected directly from industry when 

available. The NEI is a database that 

contains information about sources that 

emit criteria air pollutants and their 

precursors, and HAP. The database 

includes estimates of annual air 

pollutant emissions from point, 

nonpoint, and mobile sources in the 50 

States, the District of Columbia, Puerto 

Rico, and the Virgin Islands. EPA 

collects this information and releases an 

updated version of the NEI database 

every 3 years. 

On March 29, 2007, we published an 

ANPRM (72 FR 29287) specifically to 

request comments and updates to these 

preliminary data sets. We received 

comments on emissions data and 

emissions release characteristics data for 

facilities in these nine source categories. 

These comments were reviewed, 

considered, and the emissions 

information was adjusted where we 

concluded the comments supported 

such adjustment. After incorporation of 

changes to the data sets from this public 

data review process, the final data sets 

were created. These data sets were used 

to conduct the risk assessments and 

other analyses that form the bases for 

these proposed actions. 

In addition to gathering information 

regarding the actual emissions from the 

sources in the nine source categories, 

we also examined the underlying 

NESHAP to determine whether the 

emissions that a source was allowed to 

emit when in compliance with the 

NESHAP would significantly vary from 

the actual emissions data we had 

gathered. Where such ‘‘MACT 

allowable’’ emission levels could be 

higher than the actual emission levels, 

we extrapolated the risks associated 

with the MACT allowable emission 

levels from the risks associated with the 

actual emission levels. 

The data sets for these nine source 

categories and documentation of the 

emissions data sets used for each source 

category are available in the RTR Group 

2A docket. The documentation of the 

emission data sets provides a 

description of the changes in the dataset 

for each source category since the 

ANPRM, describes the data changes 

requested in public comments, and 

documents the analysis of MACT 

allowable emissions for each source 

category. 

2. Dispersion Modeling, Inhalation 

Exposures, and Individual and 

Population Inhalation Risks 

Both long-term and short-term 

inhalation exposure concentrations and 

health risk from each of the nine source 

categories addressed in this proposal 

were estimated using the Human 

Exposure Model (Community and 

Sector HEM–3 version 1.1.0). The HEM– 

3 performs three of the primary risk 

assessment activities listed above: (1) 

Conducting dispersion modeling to 

estimate the concentrations of HAP in 

ambient air, (2) estimating long-term 

and short-term inhalation exposures to 

individuals residing within 50 km of the 

modeled sources, and (3) estimating 

individual and population-level 

inhalation risks using the exposure 


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Federal Register / Vol. 73, No. 198 / Friday, October 10, 2008 / Proposed Rules 60441 

4Environmental Protection Agency. Revision to 

the Guideline on Air Quality Models: Adoption o 

fa Preferred General Purpose (Flat and Complex 

Terrain) Dispersion Model and Other Revisions (70 

FR 68218). November 9, 2005. 

5A typical census block is comprised of 

approximately 40 people or about 10 households. 

6National Academies of Science, 2001. Standing 

Operating Procedures for Developing Acute 

Exposure Levels for Hazardous Chemicals, page 2. 

estimates and quantitative doseresponse information. 

The dispersion model used by HEM– 

3 is AERMOD, which is one of EPA’s 

preferred models for assessing pollutant 

concentrations from industrial 

facilities.4 To perform the dispersion 

modeling and to develop the 

preliminary risk estimates, HEM–3 

draws on three data libraries. The first 

is a library of meteorological data, 

which is used for dispersion 

calculations. This library includes 1 

year of hourly surface and upper air 

observations for 130 meteorological 

stations, selected to provide thorough 

coverage of the United States and Puerto 

Rico. A second library of United States 

Census Bureau census block internal 

point locations and populations 

provides the basis of human exposure 

calculations (Census, 2000). In addition, 

the census library includes the elevation 

and controlling hill height for each 

census block, which are also used in 

dispersion calculations. A third library 

of pollutant unit risk factors and other 

health benchmarks is used to estimate 

health risks. These risk factors and 

health benchmarks are the latest values 

recommended by EPA for HAP and 

other toxic air pollutants. These values 

are available at http://www.epa.gov/ttn/ 

atw/toxsource/summary.html and are 

discussed in more detail later in this 

section. 

In developing the risk assessment for 

chronic exposures, we used the 

estimated annual average ambient air 

concentration of each HAP emitted by 

each source for which we have 

emissions data in the source category at 

each nearby census block 5 centroid as 

a surrogate for the chronic inhalation 

exposure concentration for all the 

people who reside in that census block. 

We calculated the MIR for each facility 

as the risk associated with a lifetime 

(70-year) exposure to the maximum 

concentration at the centroid of an 

inhabited census block. Individual 

cancer risks were calculated as the 

lifetime exposure to the ambient 

concentration of each HAP multiplied 

by its Unit Risk Estimate (URE), which 

is an upper bound estimate of an 

individual’s probability of contracting 

cancer over a lifetime of exposure to a 

concentration of one microgram of the 

pollutant per cubic meter of air. For 

residual risk assessments, we generally 

use URE values from EPA’s Integrated 

Risk Information System (IRIS). For 

carcinogenic pollutants without EPA 

IRIS values, we look to other reputable 

sources of cancer dose-response values, 

often using California Environmental 

Protection Agency (CalEPA) URE 

values, where available. In cases where 

new, scientifically credible doseresponse values have been developed in 

a manner consistent with EPA 

guidelines and have undergone a peer 

review process similar to that used by 

EPA, we may use such dose-response 

values in place of or in addition to other 

values. Total cancer risks were the sum 

of the risks of each carcinogenic HAP 

(including known, probable, and 

possible carcinogens) emitted by the 

modeled source. Air concentrations of 

HAP from sources other than the 

modeled source were not estimated. 

Total cancer incidence and the 

distribution of individual cancer risks 

across the population within 50 

kilometers of any source were also 

estimated as part of these assessments 

by summing individual risks. We are 

using 50 kilometers to be consistent 

with both the analysis supporting the 

1989 Benzene NESHAP (54 FR 38044) 

and the limitations of Gaussian 

dispersion modeling. 

To assess risk of noncancer health 

effects from chronic exposures, we 

summed the HQ for each HAP that 

affects a common target organ system to 

obtain the HI for that target organ 

system (or target organ-specific HI, 

TOSHI). The HQ is the estimated 

exposure divided by the chronic 

reference level, which is either the U.S. 

EPA Reference Concentration (RfC), 

defined as ‘‘an estimate (with 

uncertainty spanning perhaps an order 

of magnitude) of a continuous 

inhalation exposure to the human 

population (including sensitive 

subgroups) that is likely to be without 

an appreciable risk of deleterious effects 

during a lifetime,’’ or in cases where an 

RfC is not available, we use the CalEPA 

Chronic Reference Exposure Level 

(REL), which is defined as ‘‘the 

concentration level at or below which 

no adverse health effects are anticipated 

for a specified exposure duration,’’ or 

the ATSDR Chronic Minimum Risk 

Level (MRL), which is defined as ‘‘an 

estimate of daily human exposure to a 

substance that is likely to be without an 

appreciable risk of adverse effects (other 

than cancer) over a specified duration of 

exposure.’’ In cases where new, 

scientifically credible dose-response 

values have been developed in a manner 

consistent with EPA guidelines and 

have undergone a peer review process 

similar to that used by EPA, we may use 

such dose-response values in place of or 

in addition to other values. 

Screening estimates of acute 

exposures and risks were also evaluated 

for each HAP at any location off-site of 

each facility (i.e., not just the census 

block centroids) assuming the 

combination of a peak (hourly) emission 

rate and hourly dispersion conditions 

for the 1991 calendar year that would 

tend to maximize exposure. In each 

case, acute HQ values were calculated 

using best available short-term health 

threshold values. These acute threshold 

values include REL, Acute Exposure 

Guideline Levels (AEGL), and 

Emergency Response Planning 

Guidelines (ERPG) for 1-hour exposure 

durations. Also, for those pollutants 

where no other threshold values (REL, 

AGEL, or ERPG) were available, we used 

ATSDR MRL values for 24-hour and 

greater exposure durations. 

As described in the California 

Environmental Protection Agency’s ‘‘Air 

Toxics Hot Spots Program Risk 

Assessment Guidelines, Part I, The 

Determination of Acute Reference 

Exposure Levels for Airborne 

Toxicants,’’ an acute REL (http:// 

www.oehha.ca.gov/air/pdf/acuterel.pdf) 

is defined as ‘‘the concentration level at 

or below which no adverse health 

effects are anticipated for a specified 

exposure duration is termed the 

reference exposure level (REL). RELs are 

based on the most sensitive, relevant, 

adverse health effect reported in the 

medical and toxicological literature. 

RELs are designed to protect the most 

sensitive individuals in the population 

by the inclusion of margins of safety. 

Since margins of safety are incorporated 

to address data gaps and uncertainties, 

exceeding the REL does not 

automatically indicate an adverse health 

impact.’’ 

Acute Exposure Guideline Levels, or 

AEGLs, were derived in response to 

recommendations from the National 

Research Council. As described in 

‘‘Standing Operating Procedures (SOP) 

of the National Advisory Committee on 

Acute Exposure Guideline Levels for 

Hazardous Substances’’ (http:// 

www.epa.gov/opptintr/aegl/pubs/ 

sop.pdf), 6 ‘‘the NRC’s previous name for 

acute exposure levels—community 

emergency exposure levels (CEELs)— 

was replaced by the term AEGLs to 

reflect the broad application of these 

values to planning, response, and 

prevention in the community, the 

workplace, transportation, the military, 

and the remediation of Superfund 


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60442 Federal Register / Vol. 73, No. 198 / Friday, October 10, 2008 / Proposed Rules 

7ERP Committee Procedures and 

Responsibilities, 1 November 2006. American 

Industrial Hygiene Association. 

8See ‘‘Screening Procedures for Estimating the 

Air Quality Impact of Stationary Sources’’ 

(Revised); EPA–454/R–92–019; Chapter 4; page 15. 9See http://www.tceq.state.tx.us/compliance/ 

field_ops/eer/index.html or docket to access the 

source of these data. 

sites.’’ This document also states (page 

2) that AEGLs ‘‘represent threshold 

exposure limits for the general public 

and are applicable to emergency 

exposures ranging from 10 min to 8 h.’’ 

The document lays out the purpose and 

objectives of AEGLs by stating (page 21) 

that ‘‘the primary purpose of the AEGL 

program and the NAC/AEGL Committee 

is to develop guideline levels for oncein-a-lifetime, short-term exposures to 

airborne concentrations of acutely toxic, 

high-priority chemicals.’’ In detailing 

the intended application of AEGL 

values, the document states (page 31) 

that ‘‘It is anticipated that the AEGL 

values will be used for regulatory and 

nonregulatory purposes by U.S. Federal 

and State agencies, and possibly the 

international community in conjunction 

with chemical emergency response, 

planning, and prevention programs. 

More specifically, the AEGL values will 

be used for conducting various risk 

assessments to aid in the development 

of emergency preparedness and 

prevention plans, as well as real-time 

emergency response actions, for 

accidental chemical releases at fixed 

facilities and from transport carriers.’’ 

The AEGL–1 value is then specifically 

defined as ‘‘the airborne concentration 

of a substance above which it is 

predicted that the general population, 

including susceptible individuals, could 

experience notable discomfort, 

irritation, or certain asymptomatic 

nonsensory effects. However, the effects 

are not disabling and are transient and 

reversible upon cessation of exposure.’’ 

The document also notes (page 3) that, 

‘‘Airborne concentrations below AEGL– 

1 represent exposure levels that can 

produce mild and progressively 

increasing but transient and 

nondisabling odor, taste, and sensory 

irritation or certain asymptomatic, 

nonsensory effects.’’ Similarly, the 

document defines AEGL–2 values as 

‘‘the airborne concentration (expressed 

as ppm or mg/m3) of a substance above 

which it is predicted that the general 

population, including susceptible 

individuals, could experience 

irreversible or other serious, long-lasting 

adverse health effects or an impaired 

ability to escape.’’ 

ERPG are derived for use in 

emergency response, as described in the 

American Industrial Hygiene 

Association’s document entitled, 

‘‘Emergency Response Planning 

Guidelines (ERPG) Procedures and 

Responsibilities’’ (http://www.aiha.org/ 

1documents/committees/ERPSOPs2006.pdf), which states that, 

‘‘Emergency Response Planning 

Guidelines (ERPGs) were developed for 

emergency planning and are intended as 

health based guideline concentrations 

for single exposures to chemicals.’’ 7

The ERPG–1 value is defined as ‘‘the 

maximum airborne concentration below 

which it is believed that nearly all 

individuals could be exposed for up to 

1 hour without experiencing other than 

mild transient adverse health effects or 

without perceiving a clearly defined, 

objectionable odor.’’ Similarly, the 

ERPG–2 is defined as ‘‘the maximum 

airborne concentration below which it is 

believed that nearly all individuals 

could be exposed for up to one hour 

without experiencing or developing 

irreversible or other serious health 

effects or symptoms which could impair 

an individual’s ability to take protective 

action,’’. 

As can be seen from the definitions 

above, the AEGL and ERPG values 

include the similarly defined severity 

levels 1 and 2. For many chemicals, the 

available information does not allow 

development of a severity level 1 value 

AEGL or ERPG; in these instances, 

higher severity level AEGL–2 or ERPG– 

2 values are compared to our modeled 

exposure levels to screen for potential 

acute concerns. 

Acute REL values for a 1-hour 

exposure duration are typically lower 

than their corresponding AEGL–1 and 

ERPG–1 values. Even though their 

definitions are slightly different, AEGL– 

1 values are often the same as the 

corresponding ERPG–1 values, and 

AEGL–2 values are often equal to 

ERPG–2 values. Maximum HQ values 

from our acute screening risk 

assessments typically result when 

basing them on the acute REL for a 

particular pollutant. In cases where our 

maximum acute HQ value exceeds 1, we 

also report the HQ value based on the 

next highest acute threshold (usually 

the AEGL–1 and/or the ERPG–1). 

In cases where no acute REL, AEGL or 

ERPG value is available for the pollutant 

being assessed, we have calculated HQ 

values based on the Agency for Toxic 

Substances and Disease Registry’s 

Minimal Risk Levels (MRL) to 

determine whether we can clearly assert 

that there is no potential for acute 

impact of concern. The MRL (http:// 

www.atsdr.cdc.gov/mrls/) is defined as 

‘‘an estimate of the daily human 

exposure to a hazardous substance that 

is likely to be without appreciable risk 

of adverse noncancer health effects over 

a specified duration of exposure.’’ Since 

acute exposure is defined by ATSDR in 

the context of MRL as ‘‘exposure that 

occurs for a short time (1 to 14 days),’’ 

and since we are most interested in 

trying to assess the potential impact of 

shorter-duration high-emission events, 

we only use these HQ based on MRL 

values in the context of a screening 

check, wherein we adjust our maximum 

1-hour exposures to estimate potential 

maximum 24-hour exposures using a 

meteorological adjustment factor of 0.4.8

Because these MRL values are based on 

longer exposure durations than our peak 

1-hour exposure estimates, they are 

generally more stringent than 1-hour 

thresholds, and therefore provided a 

very conservative screen. Thus, HQ 

values based on MRL which do not 

exceed 1 provide a strong indication 

that acute impacts are not of potential 

concern. HQ values based on the MRL 

which exceed 1, however, do not 

automatically indicate an adverse health 

impact and may require further analysis. 

To develop screening estimates of 

acute exposures, we developed 

estimates of maximum hourly emission 

rates by multiplying the average annual 

hourly emission rates by a factor of 10. 

The factor of 10 is intended to cover 

routinely variable emissions and 

startup, shutdown, and malfunction 

emissions. We chose to use a factor of 

10 based on: (1) Engineering judgment, 

and (2) an analysis of short-term 

emissions data that compared hourly 

and annual emissions data for volatile 

organic compounds (VOC) for all 

facilities in a heavily-industrialized 4- 

county area (Harris, Galveston, 

Chambers, and Brazoria Counties, TX) 

over an 11-month time period in 2001.9

The analysis is provided in Appendix 4 

of the Draft Residual Risk Assessment 

for 9 Source Categories and is available 

in the docket for this rule. In this study, 

most peak emission events were less 

than twice the annual average hourly 

emission rate and the highest peak 

emission event was 8.5 times the annual 

average hourly emission rate. We 

request comment on the interpretation 

of these data and the appropriateness of 

using a factor of 10 times the average 

annual hourly emission rate in these 

acute exposure screening assessments. 

In cases where all acute HQ values 

from the screening step were less than 

or equal to 1, acute impacts were 

deemed negligible and no further 

analysis was performed. In the cases 

where an acute HQ from the screening 

step was greater than 1, additional sitespecific data were considered to 

develop a more refined estimate of the 


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10Persistent and bioaccumulative (PB) HAP are 

HAP that have the ability to persist in the 

environment for long periods of time and may also 

have the ability to build up in the food chain to 

levels that are harmful to human health and the 

environment. 

11U.S. EPA, 2006. Performing risk assessments 

that include carcinogens described in the 

Supplemental Guidance as having a mutagenic 

mode of action. Science Policy Council Cancer 

Guidelines Implementation Workgroup 

Communication II: Memo from W.H. Farland dated 

14 June 2006. http://epa.gov/osa/spc/pdfs/ 

CGIWGCommunication_II.pdf. 

12U.S. EPA, 2005. Supplemental Guidance for 

Assessing Early-Life Exposure to Carcinogens. EPA/ 

630/R-03/003F. http://www.epa.gov/ttn/atw/ 

childrens_supplement_final.pdf. 

13U.S. EPA, 2005. Science Policy Council Cancer 

Guidelines Implementation Workgroup 

Communication I: Memo from W.H. Farland dated 

4 October 2005 to Science Policy Council. http:// 

www.epa.gov/osa/spc/pdfs/canguid1.pdf. 

potential for acute impacts of concern. 

The data refinements considered 

included using a better representation of 

the peak-to-mean hourly emissions ratio 

(instead of using the default factor of 10) 

and using the site-specific facility layout 

to distinguish facility property from an 

area where the public could be exposed. 

Ideally we would prefer to have 

continuous measurements over time to 

see how the emissions vary by each 

hour over an entire year. Having a 

frequency distribution of hourly 

emission rates over a year would allow 

us to perform a probabilistic analysis to 

estimate potential threshold 

exceedances and their frequency of 

occurrence. We recognize that having 

this level of data is rare, hence our use 

of the factor of 10 multiplier approach. 

Such an evaluation could include a 

more complete statistical treatment of 

the key parameters and elements 

adopted in this screening analysis. 

In the final step of the acute impacts 

screening, HQ values exceeding 1 based 

on REL, AEGL, ERPG, or MRL values are 

interpreted on a case-by-case basis, 

considering the implications of the 

appropriate definitions and the related 

supporting documentation for that 

specific value, as well as the context of 

the HQ based on the next highest acute 

threshold value, where one is available. 

3. Multipathway Human Health Risks 

and Environmental Effects Assessment 

The potential for significant human 

health risks due to exposures via routes 

other than inhalation (i.e., 

multipathway exposures) and the 

potential for adverse environmental 

impacts were evaluated in a two-step 

screening process. In the first step, each 

source category was screened by 

determining whether any sources 

emitted any of the 14 HAP known to be 

persistent and bioaccumulative in the 

environment (also known as PB– 

HAP)10, as identified in EPA’s Air 

Toxics Risk Assessment Library 

(available at http://www.epa.gov/ttn/ 

fera/risk_atra_vol1.html). As a result of 

this screening, we determined that four 

of the RTR Group 2A source 

categories—Marine Vessel Loading 

Operations, Mineral Wool Production, 

Pharmaceuticals Production, and the 

Printing and Publishing Industry—were 

responsible for air emissions of four PB– 

HAP—cadmium compounds, mercury 

compounds, lead compounds, and 

polycyclic organic matter (POM). 

In the second step of the screening 

process, we determined if the facilityspecific emission rates of each of the 

specific PB–HAP were large enough to 

create the potential for significant noninhalation risks. To facilitate this step, 

we developed emission rate thresholds 

for each PB–HAP using a hypothetical 

screening exposure scenario developed 

for use in conjunction with the 

TRIM.FaTE model. The hypothetical 

screening scenario was subjected to a 

sensitivity analysis to ensure that its key 

design parameters were established 

such that environmental media 

concentrations were not underestimated 

(i.e., to minimize the occurrence of false 

positives, or results that suggest that 

risks might be acceptable when, in fact, 

actual risks are high), and to also 

minimize the occurrence of false 

positives for human health endpoints. 

We call this application of the 

TRIM.FaTE model TRIM-Screen. The 

facility-specific emission rates of each 

PB–HAP in each source category were 

compared to the emission threshold 

values for each of the four PB–HAP 

identified in the source category 

datasets. None of the emission rates for 

the facilities source categories addressed 

in this action exceeded the emission 

threshold values; therefore, none of the 

facilities show the potential for causing 

any significant multipathway exposures 

and risks. Had this not been the case, 

the source categories would have been 

further evaluated for potential noninhalation risks and adverse 

environmental impacts through sitespecific refined assessments using 

EPA’s TRIM.FaTE model. For further 

information on the multipathway 

screening see the ‘‘Residual Risk 

Assessment for 9 Source Categories’’ 

document (see Docket EPA–HQ–OAR– 

2008–0008). 

4. Risk Characterization 

The final product of the risk 

assessment is the risk characterization, 

in which the information from the 

previous steps is integrated and an 

overall conclusion about risk is derived. 

Estimates of health risk are considered 

in the context of uncertainties and 

limitations in the data and 

methodology. In general, we have 

attempted to reduce both uncertainty 

and bias to the greatest degree possible 

in these assessments. A brief discussion 

of the major uncertainties associated 

with the derivation of risk estimates is 

provided below. The first section 

discusses the consideration of ‘‘MACT 

allowable’’ emissions in risk 

characterization, followed by a 

discussion of uncertainties in risk 

assessments. Following these sections, 

we have provided summaries of risk 

metrics for each source category 

(including MIR and noncancer hazards, 

as well as cancer incidence estimates). 

We note here that several of the 

carcinogens emitted by these source 

categories (i.e., benzo[a]pyrene, 

dibenz[a,h]anthracene, and vinyl 

chloride) have a mutagenic mode of 

action11, EPA’s ‘‘Supplemental 

Guidance for Assessing Susceptibility 

from Early-Life Exposure to 

Carcinogens’’ 12 was applied to the risk 

estimates for these four compounds. 

This guidance has the effect of adjusting 

the URE by factors of 10 (for children 

aged 0–1), 3 (for children aged 2–15), or 

1.6 (for 70 years of exposure beginning 

at birth), as needed in risk assessments. 

In this case, this has the effect of 

increasing the estimated lifetime risks 

for these pollutants by a factor of 1.6. In 

addition, although only a small fraction 

of the total POM emissions were 

reported as individual compounds, EPA 

expresses carcinogenic potency for 

compounds in this group in terms of 

benzo[a]pyrene equivalence, based on 

evidence that carcinogenic POM have 

the same mutagenic mechanism of 

action as does benzo[a]pyrene. For this 

reason EPA implementation policy 13

recommends applying the Supplemental 

Guidance to all carcinogenic PAHs for 

which risk estimates are based on 

relative potency. Accordingly, we have 

applied the Supplemental Guidance to 

all unspeciated POM mixtures. 

Finally, we screened chronic ambient 

concentration levels of all individual 

HAP against their chronic noncancer 

human health thresholds in an effort to 

gauge the potential for adverse 

environmental impacts, under the 

assumption that chronic human toxicity 

values are generally protective of direct 

inhalation impacts on animals and 

direct contact impacts on plants. We 

believe that this assumption is 

reasonable in most cases, but 

acknowledge that it is an uncertainty. 

Although not verified for many HAP 


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60444 Federal Register / Vol. 73, No. 198 / Friday, October 10, 2008 / Proposed Rules 

14 ‘‘Evaluation of Wildlife Inhalation Exposure 

Pathway from Wood Products Plant Emissions.’’ 

Memorandum to Tim Hunt/AF&PA from David F. 

Mitchell and Julie A.F. Kabel, February 25, 2002. 

This memorandum is in the docket. 

15The mass balance used to determine emissions 

from the publication rotogravure subcategory of the 

Printing and Publishing source category includes 

emissions from startup, shutdown, and malfunction 

events. 

because of lacking environmental 

testing data, this assumption has been 

shown to be valid for some organic 

compounds 14 where such test data are 

available. 

a. Consideration of Actual and MACT 

Allowable Emissions 

We discussed the use of both MACT 

allowable and actual emissions in the 

final Coke Oven Batteries residual risk 

rule (70 FR 19998–19999, April 15, 

2005) and in the proposed and final 

Hazardous Organic NESHAP (HON) 

residual risk rules (71 FR 34428, June 

14, 2006, and 71 FR 76609, December 

21, 2006, respectively). In those 

previous actions, we noted that 

assessing the MACT allowable levels of 

emissions (i.e., the highest emission 

levels that could be emitted while 

maintaining the same activity level and 

still complying with the NESHAP 

requirements) is inherently reasonable 

since they reflect the maximum level 

sources could emit and still comply 

with national emission standards. But 

we also explained that it is reasonable 

to consider actual emissions, where 

such data are available, in both steps of 

the risk analysis, in accordance with the 

Benzene NESHAP. (54 FR 38044, 

September 14, 1989). It is reasonable to 

consider actual emissions because 

sources typically seek to perform better 

then required by emission standards to 

provide an operational cushion to 

accommodate the variability in 

manufacturing processes and control 

device performance. Failure to consider 

actual emissions data in developing risk 

estimates would unrealistically inflate 

estimated risk levels. 

We performed our risk assessments 

based on estimates of actual emission 

levels as developed through the process 

described earlier in the preamble. For 

the nine source categories addressed in 

this action, we do not have detailed 

information regarding MACT allowable 

emission levels. However, we estimated 

the potential differences in MACT 

allowable and actual emission levels for 

each source category and where MACT 

allowable emission levels were greater 

than actual emission levels, we scaled 

the risk results by the ratio of MACT 

allowable to actual emission levels. In 

many cases, the requirements of the 

regulation result in actual emission 

levels being a reasonable approximation 

of or the same as MACT allowable 

emission levels. In section I.E. of this 

preamble, the potential risk based on 

consideration of MACT allowable 

emission levels is discussed for each 

source. 

b. Uncertainties in Risk Assessments 

Uncertainty and the potential for bias 

are inherent in all risk assessments, 

including those performed for the nine 

source categories affected by this 

proposal. We reduced some of these 

uncertainties by soliciting input from 

industry and the public to develop the 

best emissions data sets possible. 

Although uncertainty exists, we believe 

the risk assessments performed for the 

nine source categories most likely 

overestimate the potential for risks due 

to the health-protective assessment 

approach. A brief discussion of the 

uncertainties in the emissions data set, 

dispersion modeling, inhalation 

exposure estimates, and dose-response 

relationships is presented in this section 

of the preamble. A more thorough 

discussion of these uncertainties is 

included in both the ‘‘Residual Risk 

Assessment for 9 Source Categories’’ 

(April 2008) and the ‘‘Risk and 

Technology Review (RTR) Assessment 

Plan’’ (November 2006), both of which 

are available in the docket. 

Uncertainties in the Emissions Data 

Sets. Although the development of the 

RTR data sets involved quality 

assurance/quality control processes, the 

accuracy of emissions values will vary 

depending on the source of the data 

present, incomplete or missing data, 

errors in estimating emissions values, 

and other factors. The emission values 

considered in this analysis are annual 

totals that do not reflect short-term 

fluctuations during the course of a year 

or variations from year to year. These 

annual emissions estimates generally do 

not include operations such as startup/ 

shutdown and malfunctions; 15

however, such emissions are not known 

to contribute significantly to total 

annual emissions. In contrast, the 

estimates of peak hourly emission rates 

for the acute effects screening 

assessment were based on the generally 

health-protective default assumption of 

10 times the annual average hourly rate 

which is intended to account for 

emission fluctuations due to normal 

facility operations as well as emissions 

from startup, shutdown and 

malfunctions events. More refined 

estimates were used for source 

categories where the screening estimates 

did not ‘‘screen out’’ all sources and 

more specific information was available. 

Facilities in seven of the source 

categories (Epichlorohydrin Elastomers 

Production, HypalonTM Production, 

Marine Tank Vessel Loading, 

Pharmaceuticals Production, 

Polybutadiene Rubber Production, 

Printing and Publishing, and Styrene 

Butadiene Rubber and Latex 

Production) emit chlorinated 

compounds and use incineration 

devices, creating the possibility for the 

formation of polychlorinated dioxins. 

However, we have no test reports or 

measurements, conducted by 

manufacturers or anyone else, 

indicating the presence of dioxins in the 

emissions from any of these source 

categories, and EPA’s dioxin inventory 

does not specifically link dioxins 

emissions to any of these source 

categories. Furthermore, in our 

judgment, it is improbable that dioxins 

are emitted in measurable amounts from 

these seven source categories given the 

low quantity of particulate matter 

present. Therefore, we did not consider 

dioxins in our assessment of these 

source categories. 

Overall we believe that the emissions 

data considered in this assessment are 

accurate representations of the actual 

emissions for facilities in the nine 

source categories for the stated purpose. 

Nevertheless, we request comment on 

our emissions data set in general 

(including information on individual 

sources), and specifically on our 

approach for estimating: short-term 

emissions used in assessing acute risk; 

emissions and associated risk from startups, shutdowns, and malfunctions 

(SSM); and on the potential for dioxins 

emissions from the source categories 

affected by this proposal. We also 

request comment on evaluating 

potential emissions mitigation (emission 

limits, work practice standards, and best 

management practices) for SSM events 

and the associated reduction in 

emissions and risks and the associated 

costs. 

Uncertainties in Dispersion Modeling. 

While the analysis employed EPA’s 

suggested regulatory dispersion model, 

AERMOD, there is uncertainty in 

ambient concentration estimates 

associated with EPA’s choice and 

application of the model. Where 

possible, model options (e.g., rural/ 

urban, plume depletion, chemistry) 

were selected to provide an 

overestimate of ambient air 

concentrations. However, because of 

practicality and data limitation reasons, 

some factors (e.g., meteorology, building 

downwash) have the potential in some 

situations to overestimate or 


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16Short-term mobility is movement from one 

microenvironment to another over the course of 

hours or days. Long-term mobility is movement 

from one residence to another over the course of a 

lifetime. 

17National-Scale Air Toxics Assessment for 1996. 

(EPA 453/R–01–003; January 2001; page 85.) 

18 IRIS glossary (http://www.epa.gov/NCEA/iris/ 

help_gloss.htm). 

19An exception to this is the URE for benzene, 

which is considered to cover a range of values, each 

end of which is considered to be equally plausible, 

and which is based on maximum likelihood 

estimates. 

20According to the NRC report Science and 

Judgment in Risk Assessment (NRC, 1994) 

‘‘[Default] options are generic approaches, based on 

general scientific knowledge and policy judgment, 

that are applied to various elements of the riskassessment process when the correct scientific 

model is unknown or uncertain.’’ The 1983 NRC 

report Risk Assessment in the Federal Government: 

Managing the Process defined default option as 

‘‘the option chosen on the basis of risk assessment 

policy that appears to be the best choice in the 

absence of data to the contrary’’ (NRC, 1983a, p. 63). 

Therefore, default options are not rules that bind 

the agency; rather, the agency may depart from 

them in evaluating the risks posed by a specific 

Continued 

underestimate ambient impacts. For 

example, meteorological data were 

taken from a single year (1991), and 

facility locations can be a significant 

distance from the site where these data 

were taken. Despite these uncertainties, 

we believe that at off-site locations and 

census block centroids, the approach 

considered in the dispersion modeling 

analysis should generally yield 

overestimates of ambient 

concentrations. 

Uncertainties in Inhalation Exposure. 

The effects of human mobility on 

exposures were not included in the 

assessment. Specifically, short-term 

mobility and long-term mobility 16

between census blocks in the modeling 

domain were not considered. As a 

result, this simplification will likely 

bias the assessment toward 

overestimating the highest exposures. In 

addition, the assessment predicted the 

chronic exposures at the centroid of 

each populated census block as 

surrogates for the exposure 

concentrations for all people living in 

that block. (On average census blocks 

are populated by approximately 40 

people.) Using the census block centroid 

to predict chronic exposures tends to 

overpredict exposures for people in the 

census block who live further from the 

facility and underpredict exposures for 

people in the census block who live 

closer to the facility. Thus, using the 

census block centroid to predict chronic 

exposures may lead to a potential 

understatement or overstatement of the 

true maximum impact, but is an 

unbiased estimate of average risk and 

incidence. 

The assessments evaluate the cancer 

inhalation risks associated with 

pollutant exposures over a 70-year 

period, the assumed lifetime of 

individuals. In reality, both the length of 

time that modeled emissions sources at 

facilities actually operate (i.e., more or 

less than 70 years), and the domestic 

growth or decline of the modeled 

industry (i.e., the increase or decrease in 

the number or size of United States 

facilities), will influence the risks posed 

by a given source category. Depending 

on the characteristics of the industry, 

these factors will likely result in an 

overestimate (or possibly an 

underestimate in the extreme case 

where a facility maintains or increases 

its emission levels beyond 70 years and 

residents live beyond 70 years at the 

same location) both in individual risk 

levels and in the total estimated number 

of cancer cases. Annual cancer 

incidence estimates from exposures to 

emissions from these sources would not 

be affected by uncertainty in the length 

of time emissions sources operate. 

The exposure estimates used in these 

analyses assume chronic exposures to 

ambient levels of pollutants. Because 

most people spend the majority of their 

time indoors, actual exposures may not 

be the same, depending on 

characteristics of the pollutants 

modeled. For many HAP, indoor levels 

are roughly equivalent to ambient 

levels, but for very reactive pollutants or 

larger particles, these levels are 

typically lower. This factor has the 

potential to result in an overstatement of 

25 to 30 percent of exposures.17

In addition to the uncertainties 

highlighted above, there are several 

factors specific to the acute exposure 

assessment that need to be highlighted. 

The accuracy of an acute inhalation 

exposure assessment depends on the 

simultaneous occurrence of 

independent factors that may vary 

greatly, such as hourly emissions rates, 

meteorology, and human activity 

patterns. In this assessment, we assume 

that individuals remain for 1 hour at the 

point of maximum ambient 

concentration as determined by the cooccurrence of peak emissions and worstcase meteorological conditions. These 

assumptions would tend to overestimate 

actual exposures since it is unlikely that 

a person would be located at the point 

of maximum exposure during the time 

of worst-case impact. 

Uncertainties in Dose-Response 

Relationships. There are uncertainties 

inherent in the development of the 

reference values used in our risk 

assessments for cancer effects from 

chronic exposures and noncancer effects 

from both chronic and acute exposures. 

Some uncertainties may be considered 

quantitatively, and others generally are 

expressed in qualitative terms. We note 

as a preface to this discussion a point 

which pertains to this whole discussion 

on dose-response uncertainty and which 

is brought out in EPA’s 2005 Cancer 

Guidelines; namely, that ‘‘the primary 

goal of EPA actions is protection of 

human health; accordingly, as an 

Agency policy, risk assessment 

procedures, including default options 

that are used in the absence of scientific 

data to the contrary, should be health 

protective.’’ (EPA 2005 Cancer 

Guidelines, pages 1–7) This is the 

approach followed here as summarized 

in the next several paragraphs. A 

complete detailed discussion of 

uncertainties and variabilities in dose 

response relationships is given in the 

risk assessment document. 

Cancer URE values used in our risk 

assessments are those that have been 

developed to generally provide an upper 

bound estimate of risk. That is, they 

represent a ‘‘plausible upper limit to the 

true value of a quantity’’ (although this 

is usually not a true statistical 

confidence limit).18 In some 

circumstances, the true risk could be as 

low as zero; however, in other 

circumstances the risk could also be 

greater.19 When developing an upper 

bound estimate of risk and to provide 

risk values that do not underestimate 

risk, health-protective default 

approaches are generally used. EPA 

typically uses the upper bound 

estimates rather than lower bound or 

central tendency estimates in our risk 

assessments, an approach that can have 

limitations for other uses (e.g., prioritysetting or expected benefits analysis). 

Chronic noncancer reference (RfC and 

RfD) values represent chronic exposure 

levels that are intended to be healthprotective levels. Specifically, these 

values provide an estimate (with 

uncertainty spanning perhaps an order 

of magnitude) of daily oral exposure 

(RfD) or of a continuous inhalation 

exposure (RfC) to the human population 

(including sensitive subgroups) that is 

likely to be without an appreciable risk 

of deleterious effects during a lifetime. 

To derive values that are intended to be 

‘‘without appreciable risk,’’ the 

methodology relies upon an uncertainty 

factor (UF) approach (U.S. EPA, 1993, 

1994) which includes consideration of 

both uncertainty and variability. When 

there are gaps in the available 

information, UF are applied to derive 

reference values that are intended to be 

protective against appreciable risk of 

deleterious effects. Uncertainty factors 

are commonly default values,20 e.g., 


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substance when it believes this to be appropriate. 

In keeping with EPA’s goal of protecting public 

health and the environment, default assumptions 

are used to ensure that risk to chemicals is not 

underestimated (although defaults are not intended 

to overtly overestimate risk). See EPA 2004 An 

examination of EPA Risk Assessment Principles 

and Practices, EPA/100/B–04/001 available at: 

http://www.epa.gov/osa/pdfs/ratf-final.pdf. 

factors of 10 or 3, used in the absence 

of compound-specific data; where data 

are available, uncertainty factors may 

also be developed using compoundspecific information. When data are 

limited, more assumptions are needed 

and more uncertainty factors are used. 

Thus there may be a greater tendency to 

overestimate risk-in the sense that 

further study might support 

development of reference values that are 

higher (i.e., less potent) because fewer 

default assumptions are needed. 

However, for some pollutants it is 

possible that risks may be 

underestimated. 

While collectively termed ‘‘UF’’, these 

factors account for a number of different 

quantitative considerations when 

utilizing observed animal (usually 

rodent) or human toxicity data in the 

development of the reference 

concentration. The UF are intended to 

account for: (1) Variation in 

susceptibility among the members of the 

human population (i.e., inter-individual 

variability); (2) uncertainty in 

extrapolating from experimental animal 

data to humans (i.e., interspecies 

differences); (3) uncertainty in 

extrapolating from data obtained in a 

study with less-than-lifetime exposure 

(i.e., extrapolating from subchronic to 

chronic exposure); (4) uncertainty in 

extrapolating the observed data to 

obtain an estimate of the exposure 

associated with no adverse effects; and 

(5) uncertainty when the database is 

incomplete or there are problems with 

the applicability of available studies. 

Many of the UF used to account for 

variability and uncertainty in the 

development of acute reference values 

are quite similar to those developed for 

chronic durations, but more often using 

individual UF values that may be less 

than 10. UF are applied based on 

chemical-specific or health effectspecific information (e.g., simple 

irritation effects do not vary appreciably 

between human individuals, hence a 

value of 3 is typically used), or based on 

the purpose for the reference value (see 

the following paragraph). The UF 

applied in acute reference value 

derivation include: (1) Heterogeneity 

among humans; (2) uncertainty in 

extrapolating from animals to humans; 

(3) uncertainty in LOAEL to NOAEL 

adjustments; and (4) uncertainty in 

accounting for an incomplete database 

on toxic effects of potential concern. 

Additional adjustments are often 

applied to account for uncertainty in 

extrapolation from observations at one 

exposure duration (e.g., 4 hours) to 

derive an acute reference value at 

another exposure duration (e.g., 1 hour). 

Not all acute reference values are 

developed for the same purpose and 

care must be taken when interpreting 

the results of an acute assessment of 

human health effects relative to the 

reference value or values being 

exceeded. Where relevant to the 

estimated exposures, the lack of 

threshold values at different levels of 

severity should be factored into the risk 

characterization as potential 

uncertainties. Further, when we 

compare our peak 1-hour exposures 

against MRL values (which are derived 

for 1- to 14-day exposure durations), we 

note that peak emission events are 

unlikely to last more than an hour. As 

such, these comparisons are a very 

conservative screen which is only useful 

in ruling out potential exposures of 

concern, limiting our ability to interpret 

situations where MRL values are 

exceeded. 

Although every effort is made to 

identify peer-reviewed reference values 

for cancer and noncancer effects for all 

pollutants emitted by the sources 

included in this assessment, some 

pollutants have no peer-reviewed 

reference values for cancer or chronic 

non-cancer or acute effects. Since 

exposures to these pollutants cannot be 

included in a quantitative risk estimate, 

an understatement of risk for these 

pollutants at environmental exposure 

levels is possible. 

Additionally, chronic reference values 

for 26 of the compounds included in 

this assessment are currently under EPA 

IRIS review and revised assessments 

may determine that these pollutants are 

more or less potent than the current 

value. We will re-evaluate residual risks 

if, as a result of these reviews, a doseresponse metric changes enough to 

indicate that the risk assessment 

supporting today’s notice may 

significantly understate human health 

risk. 

Uncertainties in the Multipathway 

and Environmental Effects Assessment. 

We generally believe that when 

exposure levels are not anticipated to 

adversely affect human health, they also 

are not anticipated to adversely affect 

the environment. While there are 

special considerations for certain HAP, 

we generally rely on the levels of PBHAP emissions to determine whether a 

full assessment of the multipathway and 

environmental effects is necessary. 

Because emissions of these chemicals 

may not be well characterized due to 

lack of testing requirements specific to 

these chemicals (e.g., these compounds 

may be aggregated into testing 

requirements for particulate matter), 

risks may be understated. 

E. What are the results of the risk 

assessment? 

The human health risks estimated for 

the nine source categories are 

summarized in this section of the 

preamble. Details of the assessment are 

located in the docket (Docket EPA–HQ– 

OAR–2008–0008), especially see 

‘‘Residual Risk Assessment for 9 Source 

Categories.’’ We believe that our 

assessment covers all potential health 

risks associated with HAP emissions 

from the nine source categories affected 

by this proposal. 

For each of the nine source categories, 

the cancer MIR from one or more 

exposure routes was greater than 1-in-1 

million and/or the maximum HQ for 

acute exposure was greater than 1. Table 

4 provides an overall summary of the 

inhalation risk assessment results, and 

the sections below provide more 

detailed discussions about the risk 

assessment results for each of the nine 

source categories. 

TABLE 4—SUMMARY OF ESTIMATED INHALATION RISKS FOR THE NINE SOURCE CATEGORIES

Source category Number of 

facilities1

Maximum 

individual 

cancer risk 

(in a million) 2

Population 

at risk ≥ 1- 

in-a-million 

(1,000’s) 

Annual 

cancer 

incidence 

Maximum 

chronic noncancer 

TOSHI 3

Maximum off-site acute noncancer HQ4

Epichlorohydrin Elastomers Production.1 30 4 0.0004 0.2 HQREL = 0.1 epichlorohydrin 

HypalonTM Production .................. 1 1 0.4 0.0004 0.1 HQREL = 0.7 chlorine 


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TABLE 4—SUMMARY OF ESTIMATED INHALATION RISKS FOR THE NINE SOURCE CATEGORIES—Continued 

Source category Number of 

facilities1

Maximum 

individual 

cancer risk 

(in a million) 2

Population 

at risk ≥ 1- 

in-a-million 

(1,000’s) 

Annual 

cancer 

incidence 

Maximum 

chronic noncancer 

TOSHI 3

Maximum off-site acute noncancer HQ4

Nitrile Butadiene Rubber Production.4 60 47 0.004 0.9 HQREL = 0.3 styrene 

Polybutadiene Rubber Production 5 10 16 0.002 0.2 HQREL = 0.3 toluene 

Styrene Butadiene Rubber and 

Latex Production.

9 7 26 0.004 0.1 HQREL = 0.3 styrene 

Marine Vessel Loading Operations.<800 1 2.4 0.01 0.006 HQAEGL–2 = 0.9 chloroform 

Mineral Wool Production .............. 8 30 110 0.008 0.4 HQREL = 8 

HQAEGL–1 = 0.7 formaldehyde 

HQREL = 4 arsenic 

Pharmaceuticals Production ......... 27 10 4.9 0.001 0.2 HQREL = 2 chloroform 

HQAEGL–1 = 0.5 acetonitrile 

Printing and Publishing Industry ... 179 0.05 0 0.000009 0.08 HQREL = 10 

HQAEGL–1 = 0.5 toluene 

1 Number of facilities evaluated in the risk analysis. 

2 Maximum individual excess lifetime cancer risk. 

3 Maximum target organ specific hazard index (TOSHI). Target organ system represented by the TOSHI varies across source categories. Maximum TOSHI is respiratory for the printing and publishing industry, mineral wood production, epichlorohydrin elastomers production, and 

Hypalon production. Maximum TOSHI for marine vessel loading operations is based on immunological effects. Maximum TOSHI for nitrile butadiene rubber production, polybutadiene rubber production, and styrene butadiene rubber and latex production is based on reproductive effects. 

Maximum TOSHI for pharmaceutical production is based on neurological effects. 4The maximum estimated acute exposure concentration was divided by available short-term threshold values to develop an array of hazard 

quotient (HQ) values. HQ values shown use the lowest available acute threshold value, which in most cases is the REL. When HQ values exceed 1, we also show HQ values using the next lowest available acute threshold. For the Mineral Wool Production Category, there were potential 

exceedances of the REL for arsenic (maximum HQ = 4, as noted in the table), but there is no corresponding AEGL–1 value to facilitate further 

interpretation of these exceedances. See Section 2 of this preamble for explanation of acute threshold values. 

As shown in Table 4, we estimate, 

based on actual emissions, that the MIR 

remaining from HAP emissions from 

these nine source categories affected by 

this proposal range from 0.05-in-1 

million to 60-in-1 million. Cancer 

incidence ranged from 0.000009 excess 

cancer cases per year (or nine cases 

every 1,000,000 years) to 0.01 excess 

cancer cases per year (or one excess 

cancer case every 100 years). No chronic 

noncancer inhalation human health 

thresholds were exceeded at off-site 

receptors for any of the nine source 

categories. The maximum acute HQ 

using the REL ranged from 0.1 to 10 and 

were all less than 1 (ranging from 0.3 to 

0.9) for the AEGL or ERPG where 

available. We extrapolated risks based 

on MACT allowable emissions in 

‘‘Estimation of MACT Allowable 

Emission Levels and Associated Risks 

and Impacts for the RTR Group 2A 

Source Categories’’ in Docket No. EPA– 

HQ–OAR–2008–0008). 

For several source categories, no PB– 

HAP emissions were reported, while 

very low levels were reported for other 

source categories. Our analyses, based 

on these low levels of emissions, 

indicate these source categories do not 

pose potential for human health 

multipathway risks or adverse 

environmental impacts. 

1. Epichlorohydrin Elastomers 

Production 

Lifetime maximum individual cancer 

risks associated with emissions modeled 

from the only one epichlorohydrin 

elastomer production facility are 

estimated to be less than 100-in-1 

million. The highest maximum lifetime 

individual cancer risk was estimated at 

30-in-1 million. The total estimated 

cancer incidence from this facility is 

0.0004 excess cancer cases per year. We 

estimate that 4,000 people exposed to 

HAP from this source category may 

experience an increased individual 

lifetime cancer risk of greater than or 

equal to 1-in-1 million. 

We found no significant risk of 

adverse noncancer health effects 

associated with the modeled acute or 

chronic inhalation exposures from the 

Epichlorohydrin Elastomers Production 

source category. The maximum chronic 

noncancer TOSHI value associated with 

emissions from this epichlorohydrin 

elastomer production facility is 0.2, and 

the maximum acute screening HQ value 

was 0.1. There were no reported PB– 

HAP emissions for this source category. 

Our analysis, based on the absence of 

PB–HAP, indicates this source category 

does not pose potential for human 

health multipathway risks or adverse 

environmental impacts. 

These risks are based on reported 

actual emission levels. Our analysis of 

potential differences between actual 

emission levels and emissions allowable 

under the NESHAP indicated that actual 

and MACT allowable emission levels 

are approximately equal. Therefore, we 

expect no appreciable differences in 

risks with consideration of MACT 

allowable emission levels. 

2. HypalonTM Production 

Lifetime maximum individual cancer 

risks associated with emissions modeled 

from the HypalonTM production facility 

are estimated to be less than 100-in-1 

million. The highest maximum lifetime 

individual cancer risk was estimated at 

1-in-1 million. The total estimated 

cancer incidence from this facility is 

0.0004 excess cancer cases per year. We 

estimate that 400 people exposed to 

HAP from this source category may 

experience an increased individual 

lifetime cancer risk of greater than or 

equal to 1-in-1 million. We found no 

significant risk of adverse noncancer 

health effects associated with the 

modeled acute or chronic inhalation 

exposures from the HypalonTM

Production source category. The 

maximum chronic noncancer TOSHI 

value associated with emissions from 

this HypalonTM production facility is 

0.1, and the maximum acute screening 

HQ value was 0.7. There were no 

reported PB HAP emissions for this 

source category. Our analysis, based on 

the absence of PB HAP, indicates this 


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source category does not pose potential 

for human health multipathway risks or 

adverse environmental impacts. 

These risks are based on reported 

actual emission levels. Our analysis of 

potential differences between actual 

emission levels and emissions allowable 

under the NESHAP indicated that actual 

and MACT allowable emission levels 

are approximately equal. Therefore, we 

expect no appreciable differences in 

risks with consideration of MACT 

allowable emission levels. 

3. Nitrile Butadiene Rubber Production 

All lifetime cancer risks associated 

with emissions modeled from the four 

NBR production facilities are estimated 

to be less than 100-in-1 million. The 

highest maximum lifetime individual 

cancer risk was estimated at 60-in-1 

million. We estimate that 47,000 people 

exposed to HAP from this source 

category may experience an increased 

individual lifetime cancer risk of greater 

than or equal to 1-in-1 million. The total 

estimated cancer incidence from these 

facilities is 0.004 excess cancer cases 

per year. We found no significant risk of 

adverse noncancer health effects 

associated with the modeled acute or 

chronic inhalation exposures from the 

Nitrile Butadiene Rubber Production 

source category. The maximum chronic 

noncancer TOSHI value associated with 

emissions from these NBR production 

facilities is 0.9, and the maximum acute 

screening HQ value for styrene is 0.3 

(relative to the acute REL). The 

maximum HQ for acrylonitrile based on 

the highest acute threshold, the AEGL– 

1, was 0.07, so we do not have any 

concerns regarding potential acute 

impacts. There were no reported PB– 

HAP emissions for this source category. 

Our analysis, based on the absence of 

PB–HAP, indicates this source category 

does not pose potential for human 

health multipathway risks or adverse 

environmental impacts. 

These risks are based on reported 

actual emission levels. Our analysis of 

potential differences between actual 

emission levels and emissions allowable 

under the NESHAP indicated that actual 

and MACT allowable emission levels 

are approximately equal. Therefore, we 

expect no appreciable differences in 

risks with consideration of MACT 

allowable emission levels. 

4. Polybutadiene Rubber Production 

All lifetime cancer risks associated 

with emissions modeled from the five 

PBR production facilities are estimated 

to be less than 100-in-1 million. The 

highest maximum lifetime individual 

cancer risk was estimated at 10-in-1 

million. The total estimated cancer 

incidence from these facilities is 0.002 

excess cancer cases per year. We 

estimate that 16,000 people exposed to 

HAP from this source category may 

experience an increased individual 

lifetime cancer risk of greater than or 

equal to 1-in-1 million. We found no 

significant risk of noncancer health 

effects associated with the modeled 

acute or chronic inhalation exposures 

from the Polybutadiene Rubber 

Production source category. The 

maximum chronic noncancer TOSHI 

value associated with emissions from 

these PBR production facilities is 0.2, 

and the maximum acute screening HQ 

value was 0.3. There were no reported 

PB–HAP emissions for this source 

category. Our analysis, based on the 

absence of PB–HAP, indicates this 

source category does not pose potential 

for human health multipathway risks or 

adverse environmental impacts. 

These risks are based on reported 

actual emission levels. While we 

estimate that MACT allowable 

emissions could be as high as five times 

the actual emission levels, we expect no 

appreciable differences in risks between 

actual emission levels and emissions 

allowable under the NESHAP because 

over 99 percent of the HAP comprising 

the additional emissions attributable to 

MACT allowable emission levels have 

no cancer potency estimates and 

because the noncancer risk contribution 

from these additional emissions is 

minimal. 

5. Styrene Butadiene Rubber and Latex 

Production 

All lifetime cancer risks associated 

with emissions modeled from the nine 

styrene butadiene rubber and latex 

production facilities are estimated to be 

less than 100-in-1 million. The highest 

maximum lifetime individual cancer 

risk was estimated at 7-in-1 million. The 

total estimated cancer incidence from 

these facilities is 0.004 excess cancer 

cases per year. We estimate that 26,000 

people exposed to HAP from this source 

category may experience an increased 

individual lifetime cancer risk of greater 

than or equal to 1-in-1 million. We 

found no significant risk of adverse 

noncancer health effects associated with 

the modeled acute or chronic inhalation 

exposures from the Styrene Butadiene 

Rubber and Latex Production source 

category. The maximum chronic 

noncancer TOSHI value associated with 

emissions from these styrene butadiene 

rubber and latex production facilities is 

0.1, and the maximum acute screening 

HQ value was 0.3. There were no 

reported PB–HAP emissions for this 

source category. Our analysis, based on 

the absence of PB–HAP, indicates this 

source category does not pose potential 

for human health multipathway risks or 

adverse environmental impacts. 

These risks are based on reported 

actual emission levels. While we 

estimate that MACT allowable 

emissions could be as high as five times 

the actual emission levels, we expect no 

appreciable differences in risks between 

actual emission levels and emissions 

allowable under the NESHAP because 

over 99 percent of the HAP comprising 

the additional emissions attributable to 

MACT allowable emission levels have 

no cancer potency estimates and 

because the noncancer risk contribution 

from these additional emissions is 

minimal. 

6. Marine Vessel Loading Operations 

All individual lifetime cancer risks 

associated with emissions from the 

marine vessel loading operations 

facilities are estimated to be less than 

100-in-1 million. The highest maximum 

lifetime individual cancer risk was 

estimated at 1-in-1 million. The total 

estimated cancer incidence from these 

facilities is 0.01 excess cancer cases per 

year. We estimate that 2,400 people 

exposed to HAP from this source 

category may experience an increased 

individual lifetime cancer risk of greater 

than or equal to 1-in-1 million. We 

found no significant risk of adverse 

noncancer health effects associated with 

the modeled acute or chronic inhalation 

exposures from the Marine Vessel 

Loading Operations source category. 

The maximum chronic noncancer 

TOSHI value associated with emissions 

from these marine vessel loading 

operations facilities is 0.006, and the 

maximum acute screening HQ value 

was 0.9 (using the REL). There were a 

few reported emissions of small 

amounts of PB–HAP including lead and 

POM. Our screening analysis, based on 

these low emission levels of PB–HAP, 

indicates this source category does not 

pose potential for human health 

multipathway risks or adverse 

environmental impacts. 

These risks are based on reported 

actual emission levels. Our analysis of 

potential differences between actual 

emission levels and emissions allowable 

under the NESHAP indicated that 

MACT allowable emission levels may be 

2 to 10 times greater than actual 

emissions. Considering this difference, 

the highest maximum lifetime 

individual cancer risk could be as high 

as 10-in-1 million, the maximum 

chronic noncancer TOSHI value could 

be up to 0.06, and the maximum acute 

HQ value using the REL could be as 

high as 9. Considering MACT allowable 

emissions, we still do not expect 


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potential for human health 

multipathway risks or adverse 

environmental impacts, based on the 

very low emissions of PB–HAP. 

7. Mineral Wool Production 

All lifetime cancer risks associated 

with emissions modeled from the eight 

mineral wool production facilities are 

estimated to be less than 100-in-1 

million. The highest maximum lifetime 

individual cancer risk was estimated at 

30-in-1 million. The total estimated 

cancer incidence from these facilities is 

0.008 excess cancer cases per year. We 

estimate that 110,000 people exposed to 

HAP from this source category may 

experience an increased individual 

lifetime cancer risk of greater than or 

equal to 1-in-1 million. We found no 

significant risk of adverse noncancer 

health effects associated with the 

modeled chronic inhalation exposures. 

The maximum chronic noncancer 

TOSHI value associated with emissions 

from these mineral wool production 

facilities is 0.4. There were a few 

reported emissions of small amounts of 

PB–HAP including cadmium, lead, and 

mercury. Our screening analysis, based 

on these low emission levels of PB– 

HAP, indicates this source category does 

not pose potential for human health 

multipathway risks or adverse 

environmental impacts. 

Potential acute impacts of concern 

were identified in the acute inhalation 

screening assessment for facilities 

emitting formaldehyde and arsenic. 

Emissions of each of these pollutants 

showed the potential to create 

maximum offsite exceedances of acute 

screening HQ values of 40 and 20 for 

formaldehyde and arsenic, respectively. 

One potential exceedance of the AEGL– 

1 value (HQAGEL¥1 = 3.0) was identified 

for formaldehyde. No AEGL or ERPG 

values at any severity level are available 

for elemental arsenic, and this makes 

the interpretation of any potential 

exceedances of the arsenic REL more 

uncertain than when such values are 

available. Subsequent discussions with 

industry experts indicated that the 

continuous nature of the process would 

not lead to large fluctuations in the 

hourly emission rates, and that a more 

reasonable, yet still health-protective, 

ratio of peak-to-mean hourly emission 

rate is 2, rather than 10. (See emissions 

documentation in the ‘‘Residual Risk for 

9 Source Categories’’ document in EPA 

Docket EPA–HQ–OAR–2008–0008). 

Application of this factor to our 

assessment still indicates the potential 

for acute concerns at two facilities, but 

reduces the maximum potential offsite 

impacts to HQ values of 8 and 4 based 

on the acute REL for formaldehyde and 

arsenic, respectively, and no HQ values 

exceeding 1 based on the AEGL or ERPG 

values for formaldehyde (HQAEGL¥1 = 

HQERPG¥1 = 0.7). Assuming peak hourly 

emissions occur throughout the year, 

meteorological conditions consistent 

with exceedances of the formaldehyde 

acute REL are estimated to occur 9 

percent of the time, and such conditions 

occur roughly 13 percent of the time for 

arsenic exceedances. Details on the 

refined acute assessment can be found 

in Appendix 7 of the ‘‘Residual Risk 

Assessment for 9 Source Categories’’ 

document. Further, under certain 

meteorological conditions, the potential 

to exceed the REL values for 

formaldehyde and arsenic exists even at 

average emission levels; this is 

estimated to potentially occur 7 percent 

of the time for formaldehyde and 4 

percent of the time for arsenic. 

Exceedances of the formaldehyde REL 

indicate the potential for eye irritation; 

exceedances of the arsenic REL indicate 

the potential for effects to reproductive 

and developmental systems. In addition, 

the threshold exceedance was of the 

REL value only and not of the AEGL or 

ERPG values. As noted in the acute REL 

documentation, ‘‘RELs are based on the 

most sensitive, relevant, adverse health 

effect reported in the medical and 

toxicological literature. RELs are 

designed to protect the most sensitive 

individuals in the population by the 

inclusion of margins of safety. Since 

margins of safety are incorporated to 

address data gaps and uncertainties, 

exceeding the REL does not 

automatically indicate an adverse health 

impact.’’ 

These risks are based on reported 

actual emission levels. Our analysis of 

potential differences between actual 

emission levels and emissions allowable 

under the NESHAP indicated that 

MACT allowable emission levels may be 

up to two times greater than actual 

emission levels. Considering this 

difference, the highest maximum 

lifetime individual cancer risk could be 

as high as 60-in-1 million, the maximum 

chronic noncancer TOSHI value could 

be up to 0.8, and the maximum acute 

HQ value could be as high as 16. 

Considering MACT allowable 

emissions, we do not expect potential 

for human health multipathway risks or 

adverse environmental impacts, based 

on the very low emissions of PB–HAP. 

8. Pharmaceuticals Production 

All lifetime cancer risks associated 

with emissions modeled from the 27 

pharmaceuticals production facilities 

are estimated to be less than 100-in-1 

million. The highest maximum lifetime 

individual cancer risk was estimated at 

10-in-1 million. The total estimated 

cancer incidence from these facilities is 

0.001 excess cancer cases per year. We 

estimate that 4,900 people exposed to 

HAP from this source category may 

experience an increased individual 

lifetime cancer risk of greater than or 

equal to 1-in-1 million. We found no 

significant risk of adverse noncancer 

health effects associated with the 

modeled chronic inhalation exposures. 

The maximum chronic noncancer 

TOSHI value associated with emissions 

from these pharmaceuticals production 

facilities is 0.2. There were a few 

reported emissions of small amounts of 

PB–HAP including lead, mercury, 

cadmium, and polynuclear aromatic 

hydrocarbons. Our screening analysis, 

based on these low emission levels of 

PB–HAP, indicates this source category 

does not pose potential for human 

health multipathway risks or adverse 

environmental impacts. 

The acute screening identified three 

facilities with a potential maximum HQ 

value greater than 1 based on REL 

values for three pollutants—methylene 

chloride, methanol, and chloroform— 

with maximum HQ values of 4, 3, and 

2, respectively. We also estimated a 

maximum HQ value of 2 for acetonitrile 

based on the AEGL–1 level. For the 

facilities that exceeded acute thresholds 

in the screening assessment, we refined 

the assessment by plotting receptors on 

facility aerial photographs and 

determining maximum offsite 

concentrations. Once we performed 

these refinements, estimated maximum 

offsite concentrations were seen to 

exceed acute REL values at one facility, 

and there were no exceedances of the 

AEGL–1 levels for acetonitrile 

(HQAEGL¥1 = 0.5). The highest offsite 

concentration of chloroform exceeds the 

REL by a factor of 2 (HQREL = 2, 

HQAEGL¥1 = 0.04). At this facility, 

meteorological conditions leading to 

offsite exceedances of the REL could 

occur as frequently as 13 hours per year, 

or about 0.1 percent of the time. HQ 

values from the refined assessment did 

not exceed 1 for either methylene 

chloride (HQREL = 1, HQAEGL¥1 = 0.03) 

or methanol (HQREL = 0.9, HQAEGL¥1 = 

0.04). The threshold exceedance was of 

the REL value for chloroform only. As 

noted in the acute REL documentation, 

‘‘RELs are based on the most sensitive, 

relevant, adverse health effect reported 

in the medical and toxicological 

literature. RELs are designed to protect 

the most sensitive individuals in the 

population by the inclusion of margins 

of safety. Since margins of safety are 

incorporated to address data gaps and 

uncertainties, exceeding the REL does 


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60450 Federal Register / Vol. 73, No. 198 / Friday, October 10, 2008 / Proposed Rules 

not automatically indicate an adverse 

health impact.’’ Details on the refined 

acute assessment can be found in 

Appendix 7 of the ‘‘Residual Risk 

Assessment for 9 Source Categories’’ 

document. 

These risks are based on reported 

actual emission levels. Our analysis of 

potential differences between actual 

emission levels and emissions allowable 

under the NESHAP indicated that 

MACT allowable emission levels may be 

up to 25 percent greater than actual 

emission levels. Considering this 

difference, the highest maximum 

lifetime individual cancer risk could be 

as high as 13-in-1 million, the maximum 

chronic noncancer TOSHI value could 

be up to 0.3, and the maximum acute 

HQ value could be as high as 3. 

Considering MACT allowable emission 

levels, we do not expect potential for 

human health multipathway risks or 

adverse environmental impacts, based 

on the very low emissions of PB–HAP. 

9. Printing and Publishing Industry 

All lifetime cancer risks associated 

with emissions modeled from the 179 

printing and publishing industry 

facilities are estimated to be less than 

100-in-1 million. The highest maximum 

lifetime individual cancer risk was 

estimated at 0.05-in-1 million. The total 

estimated cancer incidence from these 

facilities is 0.000009 excess cancer cases 

per year. We estimate that no one 

exposed to HAP from this source 

category will experience an increased 

individual lifetime cancer risk of greater 

than or equal to 1-in-1 million. We 

found no significant risk of adverse 

noncancer health effects associated with 

the modeled chronic inhalation 

exposures. The maximum chronic 

noncancer TOSHI value associated with 

emissions from these printing and 

publishing facilities is 0.08. There were 

a few reported emissions of small 

amounts of PB–HAP including 

cadmium, lead, mercury, and POM. Our 

screening analysis, based on these low 

emission levels of PB–HAP, indicates 

this source category does not pose 

potential for human health 

multipathway risks or adverse 

environmental impacts. 

The screening assessment for acute 

impacts suggests that short-term toluene 

concentrations at seven of the 

publication rotogravure facilities 

modeled could exceed the acute REL 

thresholds for toluene, assuming worstcase meteorological conditions are 

present, using our default assumption 

that the maximum hourly emissions of 

toluene exceed the average hourly 

emission rate by a factor of ten, and 

using a default source to receptor 

distance of 100 meters. Emissions of 

toluene showed the potential to create 

maximum hourly concentrations which 

could exceed the acute REL by a factor 

of 20 (HQREL = 20) and potentially reach 

the level of the AEGL–1 (HQAEGL¥1 = 1). 

Additionally, because there is no REL, 

AEGL, or ERPG value available for 

ethylene glycol, which was reported as 

being emitted from this source category, 

we used the acute MRL value as an 

acute reference value for screening. The 

results of this additional assessment 

indicated that 4 facilities showed the 

potential to exceed the MRL for 

ethylene glycol by as much as a factor 

of 3 (HQMRL = 3). As noted in the 

documentation for MRL values, 

‘‘exceeding the MRL does not 

automatically indicate an adverse health 

impact.’’ We also note that, since MRL 

values can be applied to exposure 

durations up to 14 days, these estimated 

MRL exceedances are likely to be 

overestimated. 

For the publication rotogravure 

facilities that exceeded acute toluene 

thresholds in the screening assessment, 

we refined the assessment by plotting 

receptors on facility aerial photographs 

and determining maximum offsite 

concentrations. Once we performed 

these refinements, estimated maximum 

offsite concentrations were seen to 

exceed the acute REL at six publication 

rotogravure facilities. The highest offsite 

concentration exceeds the REL by a 

factor of 10 (HQREL = 10) and is about 

half of the AEGL–1 value (HQAEGL¥1 = 

0.5). This occurs near a public road 

north of a facility. At this facility, 

meteorological conditions leading to 

offsite exceedances of the REL could 

occur as frequently as 90 hours per year, 

or about 1 percent of the time. At the 

facility where we estimate the REL to be 

most frequently exceeded, the 

maximum REL exceedance is by a factor 

of 4 (HQREL = 4), and meteorological 

conditions leading to offsite 

exceedances of the REL could occur as 

frequently as 138 hours per year, or 

about 2 percent of the time. 

Thus, the highest offsite concentration 

exceeds the REL by a factor of 10 

(HQREL = 10) and the threshold 

exceedance was of the REL value only. 

As noted in the acute REL 

documentation, ‘‘RELs are based on the 

most sensitive, relevant, adverse health 

effect reported in the medical and 

toxicological literature. RELs are 

designed to protect the most sensitive 

individuals in the population by the 

inclusion of margins of safety. Since 

margins of safety are incorporated to 

address data gaps and uncertainties, 

exceeding the REL does not 

automatically indicate an adverse health 

impact.’’ Further, based on the extensive 

information we have on this source 

category and on engineering judgment, 

we estimate that a factor of 10 emissions 

multiplier is most likely high for 

publication rotogravure printing. 

Instead of 10, we believe a more 

appropriate multiplier would be 5 or 

less. Using a multiplier of 5 (or less) 

would reduce the estimated acute 

impacts by half or more from the values 

presented. Details on the refined acute 

assessment can be found in Appendix 7 

of the ‘‘Residual Risk for 9 Source 

Categories’’ document (See Docket EPA– 

HQ–OAR–2008–0008). 

These risks are based on reported 

actual emission levels. Our analysis of 

potential differences between actual 

emission levels and emissions allowable 

under the NESHAP indicated that 

MACT allowable emission levels may be 

up to five times greater than actual 

emission levels. Considering this 

difference, the highest maximum 

lifetime individual cancer risk could be 

as high as 0.3-in-1 million, the 

maximum chronic noncancer TOSHI 

value could be up to 0.4, and the 

maximum acute HQ value could be as 

high as 50. Considering MACT 

allowable emission levels, we do not 

expect potential for human health 

multipathway risks or adverse 

environmental impacts, based on the 

very low emissions of PB–HAP. 

F. What are our proposed decisions on 

acceptability and ample margin of 

safety? 

Section 112(f) of the CAA requires 

that EPA promulgate standards for a 

category if promulgation of such 

standards is required to provide an 

ample margin of safety to protect public 

health or to prevent, taking into 

consideration costs, energy, safety, and 

other relevant factors, an adverse 

environmental effect. In determining 

whether standards are required to 

provide an ample margin of safety to 

protect public health, EPA considers 

both maximum individual cancer risk 

and risk of non-cancer health effects 

posed by emissions from the source 

category, as well as any other relevant 

public health-related information or 

factors. With regard to maximum 

individual cancer risk, the CAA states 

that if the MACT standards ‘‘do not 

reduce lifetime excess cancer risks [due 

to HAP emissions] to the individual 

most exposed to emissions from a 

source in the category or subcategory to 

less than one in one million,’’ EPA must 

promulgate residual risk standards for 

the source category (or subcategory) as 

necessary to provide an ample margin of 

safety. 


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As discussed in greater detail below, 

cancer risks to the individual most 

exposed to emissions from the Printing 

and Publishing source category are 

estimated to be below 1-in-1 million. 

After considering this information as 

well as an analysis of non-cancer health 

effects and environmental effects, we 

have determined that the current MACT 

standard provides an ample margin of 

safety to protect public health and 

prevents an adverse environmental 

effect. In reaching this conclusion, we 

did not consider costs. 

For each of the other source categories 

that are the subject of today’s proposed 

rulemaking, we estimated that risks to 

the individual most exposed to 

emissions from the category are 1-in-1 

million or greater. Following our initial 

determination that excess lifetime 

individual cancer risk to the individual 

most exposed to emissions from the 

category considered exceeds 1-in-1 

million, our approach to developing 

residual risk standards is based on a 

two-step determination of acceptable 

risk and ample margin of safety. The 

first step, determining whether risks are 

acceptable, is only a starting point for 

the analysis that determines a final 

standard. The second step determines 

an ample margin of safety, which is the 

level at which the standard is set. 

In the Benzene NESHAP, we 

explained that we will generally 

presume that if the risk to an individual 

exposed to the maximum level of a 

pollutant for a lifetime (the MIR) is no 

higher than approximately 1 in 10 

thousand (100-in-1 million), that risk 

level is considered acceptable. However, 

in determining acceptability we weigh 

the magnitude of the MIR with a series 

of other health measures and factors, 

including overall incidence of cancer or 

other serious health effects within the 

exposed population, the numbers of 

persons exposed within each individual 

lifetime risk range and associated 

incidence within, typically, a 50 km 

exposure radius around facilities, the 

science policy assumptions and 

estimation uncertainties associated with 

the risk measures, weight of the 

scientific evidence for human health 

effects, and other quantified or 

unquantified health effects. Based on 

the maximum individual cancer risk 

estimates and other health factors 

evaluated for the nine source categories, 

we have concluded that the residual risk 

for these source categories is acceptable. 

EPA must consider health and risk 

factors, as well as costs and economic 

impacts, technological feasibility, and 

other factors relevant to each particular 

decision, to complete an overall 

judgment on whether the public health 

is protected with an ample margin of 

safety. Because our analyses suggest 

risks to the individual most exposed to 

emissions equal or exceed 1-in-1 million 

after application of the NESHAP for the 

source categories other than Printing 

and Publishing, we considered the 

feasibility and costs of additional 

controls to reduce emissions and 

associated risks to address whether 

additional controls were necessary to 

provide an ample margin of safety for 

these categories. For each source 

category (with the exception of the 

Printing and Publishing), we identified 

emissions reduction options for each 

emission point contributing 

significantly to the risks and evaluated 

the costs and emission reduction 

benefits of these options. These analyses 

can be found in impacts assessment 

documents for each NESHAP, which are 

available in the docket. 

We did not consider facility-wide 

risk. Although we believe we can 

consider facility-wide risk as a relevant 

factor in determining an ample margin 

of safety, we do not have cost, technical 

feasibility, and other data to analyze 

emission sources at the facility that are 

outside the source category for the nine 

source categories in RTR Group 2A. 

The sections below and the impact 

memos in docket EPA–HQ–OAR–2008– 

0008 provide more detailed discussions 

about the emissions reduction options, 

the impacts of the emissions reduction 

options, and our ample margin of safety 

decision for each of the nine source 

categories. 

1. Epichlorohydrin Elastomers 

Production 

For the Epichlorohydrin Elastomers 

Production source category, we 

identified only one control option to 

address risks from equipment leaks, 

which were shown to drive the 

maximum individual cancer risks for 

this source category. This control option 

would require sources to install leakless 

valves to prevent leaks from those 

components. 

We estimated HAP reduction 

resulting from this control option is 

about 0.4 tons per year from the baseline 

actual emissions level. We estimated 

that achieving these reductions would 

involve a capital cost of about $725,000, 

a total annualized cost of about $99,000, 

and a cost-effectiveness of $244,000 per 

ton of HAP emissions reduced. 

Based on actual emissions, we 

estimate the maximum individual 

lifetime cancer risk is 30-in-1 million, 

the annual cancer incidence is 0.0004, 

and the population exposed to 

individual lifetime cancer risk of greater 

than or equal to 1-in-1 million is 4,000. 

The additional control requirement 

would achieve approximately 10 

percent reduction of all three of these 

cancer risk metrics at a very high cost. 

Further, the analysis based on actual 

emission levels has shown that both the 

chronic and acute noncancer hazards 

are below the threshold value of 1, 

indicating little or no potential for 

noncancer health effects resulting from 

actual emissions from the 

Epichlorohydrin Elastomers Production 

source category. We estimate that the 

MACT allowable emissions from this 

source category are approximately equal 

to the reported, actual emissions. 

Therefore, the estimated emission 

reduction, costs, and risk reduction 

discussed above would also be 

applicable to the MACT allowable 

emissions level. As a result, we propose 

that, based on actual and MACT 

allowable emissions, the existing MACT 

standard provides an ample margin of 

safety (considering cost, technical 

feasibility, and other factors) to protect 

public health. 

We are also required to consider the 

potential for adverse impacts to the 

environment as part of a residual risk 

assessment. We believe that human 

toxicity values for the inhalation 

pathway are generally protective of 

terrestrial mammals. Because the 

maximum cancer and noncancer 

hazards to humans from inhalation 

exposure are relatively low, we expect 

there to be no potential for significant 

and widespread adverse effect to 

terrestrial mammals from inhalation 

exposure to HAP emitted from the 

Epichlorohydrin Elastomers Production 

source category. As this source category 

had no reported PB–HAP emissions, no 

potential for an adverse environmental 

effect exists. Because our results showed 

no potential for any adverse 

environmental effect, we also do not 

believe there is any potential for an 

adverse effect on threatened or 

endangered species or on their critical 

habitat within the meaning of 50 CFR 

402.14(a). With these results, we have 

concluded that a consultation with the 

Fish and Wildlife Service is not 

necessary. 

In summary, we propose that the 

current MACT standard provides an 

ample margin of safety to protect public 

health. The additional control available 

is not cost-effective in light of the 

additional health protection against 

maximum individual cancer risk and 

chronic and acute noncancer hazards 

that the control would provide. In 

addition, we believe that there is no 

potential for adverse environmental 

effects. Thus, we are proposing to reVerDate Aug<31>2005 19:06 Oct 09, 2008 Jkt 217001 PO 00000 Frm 00021 Fmt 4701 Sfmt 4702 E:\FR\FM\10OCP2.SGM 10OCP2

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60452 Federal Register / Vol. 73, No. 198 / Friday, October 10, 2008 / Proposed Rules 

adopt the existing MACT standard to 

satisfy section 112(f) of the CAA. 

2. HypalonTM Production 

For the HypalonTM Production source 

category, we identified only one control 

option to address risks from back-end 

operations, which were shown to drive 

the maximum individual cancer risks 

for this source category. This control 

option would require HAP emissions 

reduction through pollution prevention 

or other measures for these operations. 

We estimated HAP reduction resulting 

from this control option is about 3.7 

tons per year from the baseline actual 

emissions level. We estimated that 

achieving these reductions would 

involve a capital cost of about 

$3,500,000, a total annualized cost of 

about $1,900,000, and a costeffectiveness of $521,000 per ton of HAP 

emissions reduced. 

Based on actual emissions, we 

estimate the maximum individual 

lifetime cancer risk is 1-in-1 million, the 

annual cancer incidence is 0.0004, and 

the population exposed to individual 

lifetime cancer risk of greater than or 

equal to 1-in-1 million is 400. The 

additional control requirement would 

achieve approximately 20 percent 

reduction of all three of these cancer 

risk metrics at a very high cost. Further, 

the analysis based on actual emission 

levels has shown that both chronic and 

acute noncancer hazards are below the 

threshold value of 1, indicating little or 

no potential for noncancer health effects 

resulting from actual emissions from the 

HypalonTM Production source category. 

We estimate that the MACT allowable 

emissions from this source category are 

approximately equal to the reported, 

actual emissions. Therefore, the 

estimated emission reduction, costs, and 

risk reduction discussed above would 

also be applicable to the MACT 

allowable emissions level. As a result, 

we propose that, based on actual and 

MACT allowable emissions, the existing 

MACT standard provides an ample 

margin of safety (considering cost, 

technical feasibility, and other factors) 

to protect public health. 

We are also required to consider the 

potential for adverse impacts to the 

environment as part of a residual risk 

assessment. As previously noted, we 

believe that human toxicity values for 

the inhalation pathway are generally 

protective of terrestrial mammals. 

Because the maximum cancer and 

noncancer hazards to humans from 

inhalation exposure are relatively low, 

we expect there to be no potential for 

significant and widespread adverse 

effect to terrestrial mammals from 

inhalation exposure to HAP emitted 

from the HypalonTM Production source 

category. As this source category had no 

reported PB–HAP emissions, no 

potential for an adverse environmental 

effect exists. Because our results showed 

no potential for an adverse 

environmental effect, we also do not 

believe there is any potential for an 

adverse effect on threatened or 

endangered species or on their critical 

habitat within the meaning of 50 CFR 

402.14(a). With these results, we have 

concluded that a consultation with the 

Fish and Wildlife Service is not 

necessary. 

In summary, we propose that the 

current MACT standard provides an 

ample margin of safety to protect public 

health. The additional control available 

is not cost effective in light of the 

additional health protection against 

maximum individual cancer risk and 

chronic and acute noncancer hazard the 

control would provide. In addition, we 

believe that there is no potential for 

adverse environmental effect. Thus, we 

are proposing to re-adopt the existing 

MACT standard to satisfy section 112(f) 

of the CAA. 

3. Nitrile Butadiene Rubber Production 

For the Nitrile Butadiene Rubber 

Production source category, we 

identified two control options; one to 

address risks from front-end process 

vent emissions and another to address 

risks from equipment leak emissions. 

Emissions from these sources were 

shown to drive the maximum individual 

cancer risk for this source category. The 

control option for front-end process 

vents would require controls to be 

placed on more vents by expanding the 

applicability of the current control 

requirements, and the control option for 

equipment leaks would involve a 

requirement to install leakless valves to 

prevent leaks from those components. 

We estimated HAP reduction resulting 

from additional front-end process vent 

controls is about 14.9 tons per year from 

the baseline actual emissions level. We 

estimated that achieving these 

reductions would involve a capital cost 

of about $310,000, a total annualized 

cost of about $750,000, and a costeffectiveness of $50,000 per ton of HAP 

emissions reduced. We estimated HAP 

reduction resulting from additional 

equipment leak controls is about 3.7 

tons per year from the baseline actual 

emissions level. We estimated that 

achieving these reductions would 

involve a capital cost of about 

$6,600,000, a total annualized cost of 

about $910,000, and a cost-effectiveness 

of $244,000 per ton of HAP emissions 

reduced. 

Based on actual emissions, we 

estimate the maximum individual 

lifetime cancer risk is 60-in-1 million, 

the annual cancer incidence is 0.004, 

and the population exposed to 

individual lifetime cancer risk of greater 

than or equal to 1-in-1 million is 47,000. 

The additional control requirement 

would achieve approximately 25 

percent reduction of all three of these 

cancer risk metrics at a very high cost. 

Further, the analysis based on actual 

emission levels has also shown that 

both the chronic and acute noncancer 

hazards are below the threshold value of 

1, indicating little or no potential for 

noncancer health effects resulting from 

actual emissions from the Nitrile 

Butadiene Rubber source category. We 

estimate that the MACT allowable 

emissions from this source category are 

approximately equal to the reported, 

actual emissions. Therefore, the 

estimated emission reduction, costs, and 

risk reduction discussed above would 

also be applicable to the MACT 

allowable emissions level. As a result, 

we propose that the existing MACT 

standard, based on actual and MACT 

allowable emissions, provides an ample 

margin of safety (considering cost, 

technical feasibility, and other factors) 

to protect public health. 

We are also required to consider the 

potential for adverse impacts to the 

environment as part of a residual risk 

assessment. As previously noted, we 

believe that human toxicity values for 

the inhalation pathway are generally 

protective of direct impacts on 

terrestrial mammals and plants. Because 

the maximum cancer and noncancer 

hazards to humans from inhalation 

exposure are relatively low, we expect 

there to be no potential for significant 

and widespread adverse effect to 

terrestrial mammals from inhalation 

exposure to HAP emitted from the 

Nitrile Butadiene Rubber Production 

source category. As this source category 

had no reported PB–HAP emissions, no 

potential for an adverse effect exists. 

Because our results showed no potential 

for an adverse environmental effect, we 

also do not believe there is any potential 

for an adverse effect on threatened or 

endangered species or on their critical 

habitat within the meaning of 50 CFR 

402.14(a). With these results, we have 

concluded that a consultation with the 

Fish and Wildlife Service is not 

necessary. 

In summary, we propose that the 

current MACT standard provides an 

ample margin of safety to protect public 

health. The additional control available 

is not cost effective in light of the 

additional health protection against 

maximum individual cancer risk and 


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Federal Register / Vol. 73, No. 198 / Friday, October 10, 2008 / Proposed Rules 60453 

chronic and acute noncancer hazard the 

control would provide. In addition, we 

believe that there is no potential for 

adverse environmental effect. Thus, we 

are proposing to re-adopt the existing 

MACT standard to satisfy section 112(f) 

of the CAA. 

4. Polybutadiene Rubber Production 

For the Polybutadiene Rubber 

Production source category, we 

identified two control options; one to 

address risks from front-end process 

vent emissions and another to address 

risks from equipment leak emissions. 

Emissions from these sources were 

shown to drive the maximum individual 

cancer risk for this source category. The 

control option for front-end process 

vents would require controls to be 

placed on more vents by expanding the 

applicability of the current control 

requirements, and the control option for 

equipment leaks would involve a 

requirement to install leakless valves to 

prevent leaks from those components. 

We estimated HAP reduction 

resulting from additional front-end 

process vent controls is about 178 tons 

per year from the baseline actual 

emissions level. We estimated that 

achieving these reductions would 

involve a capital cost of about $310,000, 

a total annualized cost of about 

$750,000, and a cost-effectiveness of 

$4,000 per ton of HAP emissions 

reduced. We estimated HAP reduction 

resulting from additional equipment 

leak controls is about 52 tons per year 

from the baseline actual emissions level. 

We estimated that achieving these 

reductions would involve a capital cost 

of about $93,000,000, a total annualized 

cost of about $13,000,000, and a costeffectiveness of $244,000 per ton of HAP 

emissions reduced. 

Based on actual emissions, we 

estimate the maximum individual 

lifetime cancer risk is 10-in-1 million, 

the annual cancer incidence is 0.002, 

and the population exposed to 

individual lifetime cancer risk of greater 

than or equal to 1-in-1 million is 16,000. 

The additional control requirement 

would achieve approximately 10 

percent reduction of all three of these 

cancer risk metrics at a relatively high 

cost considering that risks are low under 

the current MACT standard and that the 

reduction in risks is relatively small. 

Further, the analysis based on actual 

emissions has shown that both the 

chronic and acute noncancer hazards 

are below the threshold value of 1. 

We estimate that the MACT allowable 

emissions from this source category are 

as high as five times actual emission 

levels. However, the additional 

emissions represented by the MACT 

allowable emissions level are released 

from a part of the production process 

that does not contribute appreciably to 

the risks and for which the control 

option would not affect emission levels. 

Therefore, we believe that the estimated 

emission reductions, costs, and risk 

reduction discuss above would also be 

applicable to the MACT allowable 

emissions level. As a result, we propose 

that, based on actual and MACT 

allowable emission levels, the existing 

MACT standard provides an ample 

margin of safety (considering cost, 

technical feasibility, and other factors) 

to protect public health. 

We are also required to consider the 

potential for adverse impacts to the 

environment as part of a residual risk 

assessment. As previously noted, we 

believe that human toxicity values for 

the inhalation pathway are generally 

protective of terrestrial mammals. 

Because the maximum cancer and 

noncancer hazards to humans from 

inhalation exposure are relatively low, 

we expect there to be no potential for 

significant and widespread adverse 

effect to terrestrial mammals from 

inhalation exposure to HAP emitted 

from the Polybutadiene Rubber 

Production source category. As this 

source category had no reported PB– 

HAP emissions, no potential for an 

adverse effect exists. Because our results 

showed no potential for an adverse 

environmental effect, we also do not 

believe there is any potential for an 

adverse effect on threatened or 

endangered species or on their critical 

habitat within the meaning of 50 CFR 

402.14(a). With these results, we have 

concluded that a consultation with the 

Fish and Wildlife Service is not 

necessary. 

In summary, we propose that the 

current MACT standard provides an 

ample margin of safety to protect public 

health. The additional control available 

is not cost-effective in light of the 

additional health protection against 

maximum individual cancer risk and 

chronic and acute noncancer hazard the 

control would provide. In addition, we 

believe that there is no potential for 

adverse environmental effect. Thus, we 

are proposing to re-adopt the existing 

MACT standard to satisfy section 112(f) 

of the CAA. 

5. Styrene Butadiene Rubber and Latex 

Production 

For the Styrene Butadiene Rubber and 

Latex Production source category, we 

identified one available control option 

to address risks from equipment leaks, 

which were shown to drive the 

maximum individual cancer risks for 

this source category. This control option 

would involve a requirement to install 

leakless valves to prevent leaks from 

those components. 

We estimated HAP reduction 

resulting from installing leakless valves 

is about 6 tons per year from the 

baseline actual emissions level. We 

estimated that achieving these 

reductions would involve a capital cost 

of about $10,600,000, a total annualized 

cost of about $1,500,000, and a costeffectiveness of $244,000 per ton of HAP 

emissions reduced. 

Based on actual emissions, we 

estimate the maximum individual 

lifetime cancer risk is 7-in-1 million, the 

annual cancer incidence is 0.004, and 

the population exposed to individual 

lifetime cancer risk of greater than or 

equal to 1-in-1 million is 26,000. The 

additional control requirement would 

achieve approximately 25 percent 

reduction of all three of these cancer 

risk metrics at a relatively high cost. 

Further, the analysis based on actual 

emissions has shown that both the 

chronic and acute noncancer hazards 

are below the threshold value of 1. 

We estimate that the MACT allowable 

emissions from this source category are 

as high as four times actual emission 

levels. However, the additional 

emissions represented by the MACT 

allowable emissions level are released 

from a part of the production process 

that does not contribute appreciably to 

the risks and for which the control 

option would not affect emission levels. 

Therefore, we believe that the estimated 

emission reductions, costs, and risk 

reduction discussed above would also 

be applicable to the MACT allowable 

emissions level. As a result, we propose 

that, based on actual and MACT 

allowable emission levels, the existing 

MACT standard provides an ample 

margin of safety (considering cost, 

technical feasibility, and other factors) 

to protect public health. 

We are also required to consider the 

potential for adverse impacts to the 

environment (as part of a residual risk 

assessment. As previously noted, we 

believe that human toxicity values for 

the inhalation pathway are generally 

protective of terrestrial mammals. 

Because the maximum cancer and 

noncancer hazards to humans from 

inhalation exposure are relatively low, 

we expect there to be no potential for 

significant and widespread adverse 

effect to terrestrial mammals from 

inhalation exposure to HAP emitted 

from the Styrene Butadiene Rubber and 

Latex Production source category. As 

this source category had no reported 

PB–HAP emissions, no potential for an 

adverse effect was identified. Since our 

results showed no potential for an 


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adverse environmental effect, we also 

do not believe there is any potential for 

an adverse effect on threatened or 

endangered species or on their critical 

habitat within the meaning of 50 CFR 

402.14(a). With these results, we have 

concluded that a consultation with the 

Fish and Wildlife Service is not 

necessary. 

In summary, we propose that the 

current MACT standard provides an 

ample margin of safety to protect public 

health. The additional control available 

is not cost-effective in light of the 

additional health protection against 

maximum individual cancer risk and 

chronic and acute noncancer hazard the 

control would provide. In addition, we 

believe that there is no potential for 

adverse environmental effect. Thus, we 

are proposing to re-adopt the existing 

MACT standard to satisfy section 112(f) 

of the CAA. 

6. Marine Vessel Loading Operations 

For the Marine Vessel Loading 

Operations source category, we 

identified one control option to address 

risks from ethylene dichloride 

emissions, which were shown to drive 

the maximum individual cancer risks 

for this source category. This control 

option would require the same 

performance standard specified in the 

original MACT standard to be used at 

more facilities by lowering the 

applicability limit for ethylene 

dichloride emissions from 10 tons per 

year to approximately 2.6 tons per year. 

We estimated HAP reduction resulting 

from this control option is about 15 tons 

per year from the baseline actual 

emissions level. We estimated that 

achieving these reductions would 

involve a capital cost of about 

$57,000,000, a total annualized cost of 

about $11,000,000, and a costeffectiveness of over $700,000 per ton of 

HAP emissions reduced. 

Based on actual emissions, we 

estimate the maximum individual 

lifetime cancer risk is 1-in-1 million, the 

annual cancer incidence is 0.01, and the 

population exposed to individual 

lifetime cancer risk of greater than or 

equal to 1-in-1 million is 2,400. The 

additional control requirement would 

achieve approximately 5 percent 

reduction of all three of these cancer 

risk metrics at a very high cost. The 

analysis based on actual emission levels 

has also shown that both the chronic 

and acute noncancer risks are below the 

threshold value of 1. 

We estimate that the MACT allowable 

emissions from this source category 

could be 10 times the reported actual 

emissions, which could potentially 

result in risk impacts up to 10 times 

those estimated for the actual emissions 

level. Assuming all impacts were 

proportional to those predicted for 

actual emissions, this control option 

would result in an emission reduction 

of around 150 tons per year (based on 

a factor of 10). The risk reduction would 

still be minimal. The cost would not 

differ, resulting in a cost effectiveness of 

around $700,000 per ton based on 

MACT allowable emissions. 

As a result, we propose that, based on 

actual and MACT allowable emissions, 

the existing MACT standard provides an 

ample margin of safety (considering 

cost, technical feasibility, and other 

factors) to protect public health. 

We are also required to consider the 

potential for adverse impacts to the 

environment as part of a residual risk 

assessment. As previously noted, we 

believe that human toxicity values for 

the inhalation pathway are generally 

protective of terrestrial mammals. 

Because the maximum cancer and 

noncancer hazards to humans from 

inhalation exposure are relatively low, 

we expect there to be no significant and 

widespread adverse effect to terrestrial 

mammals from inhalation exposure to 

HAP emitted from the Marine Vessel 

Loading Operations source category. To 

assess the potential for adverse effect to 

other wildlife, we have carried out a 

screening-level assessment of adverse 

environmental effects via exposure to 

PB–HAP emissions. This source 

category reported PB–HAP emissions, 

but, based on our application of the 

screening scenario developed for 

TRIM.FaTE model, no potential for an 

adverse environment effect via 

multipathway exposures was identified. 

Because our results showed no potential 

for an adverse environmental effect, we 

also do not believe there is any potential 

for an adverse effect on threatened or 

endangered species or on their critical 

habitat within the meaning of 50 CFR 

402.14(a). With these results, we have 

concluded that a consultation with the 

Fish and Wildlife Service is not 

necessary. 

In summary, we propose that the 

current MACT standard provides an 

ample margin of safety to protect public 

health. The additional control available 

is not cost-effective in light of the 

additional health protection against 

maximum individual cancer risk and 

chronic and acute noncancer hazard the 

control would provide. In addition, we 

believe that there is no potential for 

adverse environmental effect. Thus, we 

are proposing to re-adopt the existing 

MACT standard to satisfy section 112(f) 

of the CAA. 

7. Mineral Wool Production 

For the Mineral Wool Production 

source category, we identified one 

available control option to address risks 

from fiber collection and cooling 

chambers, the emission points which 

were shown to drive the maximum 

individual cancer risks for this source 

category. This control option would 

require sources to add thermal 

incinerators to control emissions from 

these areas. 

We estimated HAP reduction 

resulting from this control option is 

about 48 tons per year from the baseline 

actual emissions level. We estimated 

that achieving these reductions would 

involve a capital cost of about 

$65,000,000, a total annualized cost of 

about $13,000,000, and a costeffectiveness of $270,000 per ton of HAP 

emissions reduced. 

Based on actual emissions, we 

estimate the maximum individual 

lifetime cancer risk is 30-in-1 million, 

the annual cancer incidence is 0.008, 

and the population exposed to 

individual lifetime cancer risk of greater 

than or equal to 1-in-1 million is 

110,000. The additional control 

requirement would achieve less than 10 

percent reduction of all three of these 

cancer risk metrics at a very high cost. 

The analysis has also shown that the 

chronic noncancer hazards are low 

based on actual emissions. While the 

refined assessment for acute impacts 

using actual emission suggests that 

short-term arsenic and formaldehyde 

concentrations at five modeled facilities 

could exceed their acute REL values by 

as much as factors of 4 and 8, 

respectively, if worst-case 

meteorological conditions (which occur 

roughly 10 percent of the time) are 

present at the same time that maximum 

hourly emissions of these chemicals 

exceed the average hourly emission rate 

by a factor of 2. However, as noted 

earlier in this preamble, exceedances of 

these REL values may occur even at 

average emission rates for roughly 10 

percent of the hours in a year. In 

addition, the threshold exceedance was 

of the REL value only. As noted in the 

acute REL documentation, ‘‘RELs are 

based on the most sensitive, relevant, 

adverse health effect reported in the 

medical and toxicological literature. 

RELs are designed to protect the most 

sensitive individuals in the population 

by the inclusion of margins of safety. 

Since margins of safety are incorporated 

to address data gaps and uncertainties, 

exceeding the REL does not 

automatically indicate an adverse health 

impact.’’ 


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We estimate that the MACT allowable 

emissions from this source category 

could be as high as two times the 

reported actual emissions, which could 

potentially result in risk impacts double 

those estimated for the actual emissions 

level. Assuming all impacts were 

proportional to those predicted for 

actual emissions, this incinerator 

control option would result in an 

emission reduction of around 96 tons 

per year and a risk reduction of 

approximately 20 percent. The cost 

would not differ, resulting in a cost 

effectiveness of around $135,000 per ton 

based on MACT allowable emissions. 

Finally, the REL value for arsenic is 

designed for a four hour exposure 

whereas the exposure duration used in 

the modeling scenario was one hour, 

making the use of the REL in this 

application more protective of human 

health than if the exposure durations 

were the same. Considering these 

factors, although we cannot completely 

rule out the potential for acute impacts 

from formaldehyde or arsenic at these 

facilities, we believe it to be unlikely 

any acute health impacts would actually 

occur. As a result, we propose that, 

based on actual and MACT allowable 

emissions levels, the existing MACT 

standard, provides an ample margin of 

safety (considering cost, technical 

feasibility, and other factors) to protect 

public health. 

We are also required to consider the 

potential for adverse impacts to the 

environment as part of a residual risk 

assessment. As previously noted, we 

believe that human toxicity values for 

the inhalation pathway are generally 

protective of terrestrial mammals. 

Because the maximum cancer and 

noncancer hazards to humans from 

inhalation exposure are relatively low, 

we expect there to be no potential for 

significant and widespread adverse 

effect to terrestrial mammals from 

inhalation exposure to HAP emitted 

from the Mineral Wool Production 

source category. To evaluate the 

potential for adverse effects to other 

wildlife, we carried out a screeninglevel assessment of adverse 

environmental effects via exposure to 

PB–HAP emissions. This source 

category reported PB–HAP emissions, 

but, based on our application of the 

screening scenario developed for 

TRIM.FaTE model, no potential for an 

adverse environment effect via 

multipathway exposures was identified. 

Because our results showed no potential 

for an adverse environmental effect, we 

also do not believe there is any potential 

for an adverse effect on threatened or 

endangered species or on their critical 

habitat within the meaning of 50 CFR 

402.14(a). With these results, we have 

concluded that a consultation with the 

Fish and Wildlife Service is not 

necessary. 

In summary, we propose that the 

current MACT standard provides an 

ample margin of safety to protect public 

health. The additional control available 

is not cost-effective in light of the 

additional health protection against 

maximum individual cancer risk and 

chronic and acute noncancer hazard the 

control would provide. In addition, we 

believe that there is no potential for 

adverse environmental effect. Thus, we 

are proposing to re-adopt the existing 

MACT standard to satisfy section 112(f) 

of the CAA. 

8. Pharmaceuticals Production 

For the Pharmaceuticals Production 

source category, we identified one 

available control option to address risks 

from equipment leaks, which were 

shown to drive the maximum individual 

cancer risks for this source category. 

This control option would involve a 

work practice requirement to monitor 

valves monthly until fewer than 0.5 

percent of valves are leaking. 

We estimated HAP reduction 

resulting from this control option is 

about 107 tons per year from the 

baseline actual emissions level. We 

estimated that achieving these 

reductions would involve no capital 

costs, a total annualized cost of about 

$820,000, and a cost-effectiveness of 

$7,600 per ton of HAP emissions 

reduced. 

Based on actual emissions, we 

estimate the maximum individual 

lifetime cancer risk is 10-in-1 million, 

the annual cancer incidence is 0.001, 

and the population exposed to 

individual lifetime cancer risk of greater 

than or equal to 1-in-1 million is 4,900. 

The application of the additional 

control option would reduce all three of 

these relatively low cancer risks metrics 

by less than 10 percent. We propose that 

the costs for this option are 

disproportionate to the limited cancer 

health benefit potentially achievable 

with the controls. Further, the analysis 

has also shown that both the chronic 

and acute noncancer hazards are low, 

based on actual emissions. While the 

assessment for acute impacts using 

actual emissions suggests that shortterm chloroform concentrations at one 

modeled facility could exceed the acute 

threshold, this is only if worst-case 

meteorological conditions are present 

(estimated at roughly 0.1 percent of the 

year) at the same time that maximum 

hourly emissions of these chemicals 

exceed the average actual hourly 

emission rate by a factor of 5. In 

addition, the threshold exceedance was 

of the REL value only. As noted in the 

acute REL documentation, ‘‘RELs are 

based on the most sensitive, relevant, 

adverse health effect reported in the 

medical and toxicological literature. 

RELs are designed to protect the most 

sensitive individuals in the population 

by the inclusion of margins of safety. 

Since margins of safety are incorporated 

to address data gaps and uncertainties, 

exceeding the REL does not 

automatically indicate an adverse health 

impact.’’ Finally, the REL value for 

chloroform (the only HAP with the 

potential for acute impacts in the 

refined analysis) is designed for a 7- 

hour exposure, whereas the exposure 

duration used in the modeled scenario 

was 1 hour, making the uses of the REL 

in this application more protective of 

human health than if the exposure 

durations were the same. Considering 

these factors, we believe it to be 

unlikely any acute health impacts 

would actually occur. 

We estimate that the MACT allowable 

emissions from this source category 

could be as much as 25 percent higher 

than the reported actual emissions, 

which could potentially result in risk 

impacts 25 percent higher than those 

estimated for the actual emissions level. 

Assuming all impacts are proportional 

to those predicted for actual emissions, 

this equipment leak control option 

would result in an emission reduction 

of around 130 tons per year. The risk 

reduction would still be minimal. The 

cost would not differ, although the cost 

effectiveness would be somewhat lower 

at over $6,000 per ton when based on 

MACT allowable emissions. As a result, 

we propose that, based on actual and 

MACT allowable emissions, the existing 

MACT standard provides an ample 

margin of safety (considering cost, 

technical feasibility, and other factors) 

to protect public health. 

We are also required to consider the 

potential for adverse impacts to the 

environment as part of a residual risk 

assessment. As previously noted, we 

believe that human toxicity values for 

the inhalation pathway are generally 

protective of terrestrial mammals. 

Because the maximum cancer and 

noncancer hazards to humans from 

inhalation exposure are relatively low, 

we expect there to be no potential for 

significant and widespread adverse 

effect to terrestrial mammals from 

inhalation exposure to HAP emitted 

from the Pharmaceuticals Production 

source category. To evaluate the 

potential for adverse effect to other 

wildlife, we carried out a screeninglevel assessment of adverse 


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60456 Federal Register / Vol. 73, No. 198 / Friday, October 10, 2008 / Proposed Rules 

environmental effects via exposure to 

PB–HAP emissions. This source 

category reported PB–HAP emissions, 

but, based on our application of the 

screening scenario developed for 

TRIM.FaTE model, no potential for an 

adverse environment effect via 

multipathway exposures was identified. 

Since our results showed no potential 

for an adverse environmental effect, we 

also do not believe there is any potential 

for an adverse effect on threatened or 

endangered species or on their critical 

habitat within the meaning of 50 CFR 

402.14(a). With these results, we have 

concluded that a consultation with the 

Fish and Wildlife Service is not 

necessary. 

In summary, we propose that the 

current MACT standard provides an 

ample margin of safety to protect public 

health. The additional control available 

is not cost-effective in light of the 

additional health protection against 

maximum individual cancer risk and 

chronic and acute noncancer hazard the 

control would provide. In addition, we 

believe that there is no potential for 

adverse environmental effect. Thus, we 

are proposing to re-adopt the existing 

MACT standard to satisfy section 112(f) 

of the CAA. 

9. Printing and Publishing Industry 

The Printing and Publishing source 

category emits HAP which are known, 

probable, or possible carcinogens. EPA 

evaluated the emissions of these HAP 

and determined that they pose 

maximum individual cancer risks less 

than 1-in-1 million to the individual 

most exposed. Because these risks are 

less than 1-in-1 million, EPA is not 

required to promulgate standards under 

112(f)(2) for the Printing and Publishing 

source category unless promulgation of 

standards is required to prevent an 

adverse environmental effect. 

Accordingly, EPA undertook further 

analysis to assess whether 

environmental effects might result from 

emissions from this source category. 

Our analysis demonstrated that 

chronic noncancer risks are expected to 

be low, based on actual and MACT 

allowable emissions. We determined 

that emissions from the Printing and 

Publishing category would result in 

chronic noncancer target organ-specific 

HI less than or equal to 1 for the 

individual most exposed. Thus we do 

not anticipate that actual or MACT 

allowable emissions would result in 

adverse chronic noncancer health 

effects. 

While the refined assessment for 

acute impacts suggests that short-term 

toluene concentrations at six modeled 

facilities could exceed acute thresholds, 

we believe it unlikely that acute impacts 

would occur. Acute impacts of policy 

significance are unlikely because we 

based the refined assessment on worstcase meteorological conditions 

(estimated to occur up to 2 percent of 

the time) being present at the same time 

that maximum hourly emissions of 

toluene exceed the average hourly 

emission rate by a factor of 10, 

coincident with individuals being in the 

location of maximum impact. This set of 

assumptions results in an estimate of a 

10-fold exceedance of the toluene REL. 

As noted in the acute REL 

documentation, ‘‘RELs are based on the 

most sensitive, relevant, adverse health 

effect reported in the medical and 

toxicological literature. RELs are 

designed to protect the most sensitive 

individuals in the population by the 

inclusion of margins of safety. Since 

margins of safety are incorporated to 

address data gaps and uncertainties, 

exceeding the REL does not 

automatically indicate an adverse health 

impact.’’ 

We are also required to consider the 

potential for adverse impacts to the 

environment as part of a residual risk 

assessment. As previously noted, we 

believe that human toxicity values for 

the inhalation pathway are generally 

protective of terrestrial mammals. 

Because the maximum cancer and 

noncancer hazards to humans from 

inhalation exposure are low, we expect 

there to be no potential for significant 

and widespread adverse effect to 

terrestrial mammals from inhalation 

exposure to HAP emitted from the 

Printing and Publishing Industry source 

category. To evaluate the potential for 

adverse effect to other wildlife, we 

carried out a screening-level assessment 

of adverse environmental effects via 

exposure to PB–HAP emissions. This 

source category reported PB–HAP 

emissions, but, based on our application 

of the screening scenario developed for 

TRIM.FaTE model, no potential for an 

adverse environment effect via 

multipathway exposures was identified. 

Because our results showed no potential 

for an adverse environmental effect, we 

also do not believe there is any potential 

for an adverse effect on threatened or 

endangered species or on their critical 

habitat within the meaning of 50 CFR 

402.14(a). With these results, we have 

concluded that a consultation with the 

Fish and Wildlife Service is not 

necessary. 

In summary, we propose that the 

current MACT standard provides an 

ample margin of safety to protect public 

health because the maximum individual 

cancer risk is below 1-in-1 million, the 

chronic noncancer risks are low, and the 

acute noncancer hazards are below a 

level of concern. In addition, we believe 

that there is no potential for adverse 

environmental effect. In reaching this 

conclusion, we did not consider costs. 

Thus, we are proposing to re-adopt the 

existing MACT standard to satisfy 

section 112(f) of the CAA. 

G. What are the results of the technology 

review? 

Section 112(d)(6) of the CAA requires 

us to review and revise MACT 

standards, as necessary, every 8 years, 

taking into account developments in 

practices, processes, and control 

technologies that have occurred during 

that time. This authority provides us 

with broad discretion to revise the 

MACT standards as we determine 

necessary, and to account for a wide 

range of relevant factors. We interpret 

CAA section 112(d)(6) as requiring us to 

consider developments in pollution 

control in the industry ‘‘taking into 

account developments in practices, 

processes, and control technologies,’’ 

and to assess the costs of potentially 

stricter standards reflecting those 

developments (69 FR 48351). We 

consider ‘‘developments in practices, 

processes, and control technologies’’ to 

be: 

• Any add-on control technology or 

other equipment (e.g., floating roofs for 

storage tanks) that was not identified 

and considered during MACT 

development for the source category, 

• Any improvements in add-on 

control technology or other equipment 

(that was identified and considered 

during MACT development for the 

source category) that could result in 

significant additional emission 

reduction, 

• Any work practice or operational 

procedure that was not identified and 

considered during MACT development 

for the source category, and 

• Any process change or pollution 

prevention alternative that could be 

broadly applied that was not identified 

and considered during MACT 

development for the source category. 

For the source categories in RTR 

Group 2A, our review of developments 

in practices, processes, and control 

technologies has been on-going since 

promulgation of the five NESHAP. In 

the years since the RTR Group 2A 

NESHAP were promulgated, EPA has 

developed air toxics regulations for a 

number of source categories that emit 

HAP from the same type of emission 

sources and have evaluated practices, 

processes, and control techniques for 

each rulemaking. Thus, the first source 

of information about practices, 

processes, and control technologies is 


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our own data and experience with the 

various industry sectors and source 

categories. 

The second source of information is 

EPA’s RACT/BACT/LAER 

clearinghouse. The RACT/BACT/LAER 

clearinghouse is an EPA-maintained 

central data base of case-specific 

information on the ‘‘Best Available’’ air 

pollution technologies that have been 

required to reduce the emissions of air 

pollutants from stationary sources (e.g., 

power plants, steel mills, chemical 

plants, etc.). The third source of 

information is information received 

directly from the industry regarding any 

developments in practices, processes, or 

controls. 

The sections below provide more 

discussion about the technology review 

analyses and results for each of the nine 

source categories. More detail about the 

technology review can be found in the 

technology review documents written 

for each source category. The 

technology review documents are in the 

RTR Group 2A docket. 

1. Polymers and Resins I 

In the decade since the Polymers and 

Resins I NESHAP was promulgated, 

EPA has developed 18 air toxics 

regulations for source categories that 

emit organic HAP from the same type of 

emission sources that are present in the 

five Polymers and Resins source 

categories in RTR Group 2A. We 

reviewed the regulatory requirements 

and/or technical analyses for these 18 

regulations for new practices, processes, 

and control techniques. We also 

conducted a search of the BACT/RACT/ 

LAER clearinghouse for controls for 

VOC- and HAP-emitting processes in 

the Polymers and Resins and the 

Synthetic Organic Chemical 

Manufacturing Industry (SOCMI) 

categories with permits dating back to 

1997. In addition to these two sources 

of information, we obtained information 

directly from the industry regarding any 

developments in practices, processes, or 

controls. 

We identified no advancements in 

practices, processes, and control 

technologies applicable to the emission 

sources in the Polymers and Resins I 

source categories in our technology 

review. 

2. Marine Vessel Loading Operations 

In the decade since the Marine Vessel 

Loading NESHAP was promulgated, 

EPA has developed eight air toxics 

regulations for source categories that 

emit organic HAP from the same type of 

emission sources that are present in the 

marine vessel loading source category. 

We reviewed the regulatory 

requirements and/or technical analyses 

for these eight regulations for new 

practices, processes, and control 

techniques. We also conducted a search 

of the BACT/RACT/LAER clearinghouse 

for controls for VOC- and HAP-emitting 

loading processes in the Organic Liquid 

Storage and Marketing categories with 

permits dating back to 1997. In addition 

to these two sources of information, we 

also obtained information from 

industries with similar emissions 

sources with potentially transferable 

controls to determine if they have any 

developments in practices, processes, or 

controls that could be applied here. 

We identified no advancements in 

practices, processes, and control 

technologies applicable to the emission 

sources in the Marine Vessel Loading 

source category in our technology 

review. 

3. Mineral Wool Production 

Since the Mineral Wool NESHAP was 

promulgated, EPA has developed 

several air toxics regulations for source 

categories that emit organic HAP from 

similar types of emission sources that 

are present in the mineral wool source 

category. These similar types of 

emissions sources include both melting 

furnaces and curing ovens. We reviewed 

the regulatory requirements and/or 

technical analyses associated with each 

of the subsequent regulatory actions to 

identify any practices, processes, and 

control techniques considered in these 

efforts that could possibly be applied to 

the Mineral Wool Production source 

category. In addition to the review of 

subsequent regulatory actions for 

similar emissions types such as melting 

furnaces and curing ovens, EPA 

conducted a review for other VOC- and 

organic HAP-emitting processes that 

have similar technology-transferable 

controls. 

We also conducted a search of the 

BACT/RACT/LAER clearinghouse for 

the Mineral Wool Production source 

category and found the following 

processes, practices, and control 

technologies: wet scrubbers for 

particulate matter (PM); baghouse dust 

collectors for PM; electrostatic 

precipitators for PM; and thermal 

oxidizer for VOC. These practices, 

processes, and control technologies are 

all examples of the types of emission 

reduction techniques that were 

considered in the development of the 

Mineral Wool MACT standard. In 

addition to the search for similar 

processes such as cupolas, melting 

ovens or furnaces, and curing ovens, we 

conducted a search for other PM, HAP 

metals, VOC, and organic HAP 

processes that have similar, technologytransferable controls. No developments 

in practices, processes, or control 

technologies were revealed as a result of 

that search. 

In addition to these two sources of 

information, we also obtained 

information from industries with 

technology transferable controls 

regarding developments in practices, 

processes, or controls. 

We identified no advancements in 

practices, processes, and control 

technologies applicable to the emission 

sources in the Mineral Wool Production 

source category in our technology 

review. 

4. Pharmaceuticals Production 

In the decade since the 

Pharmaceutical NESHAP was 

promulgated, EPA has developed 10 air 

toxics regulations for source categories 

that emit organic HAP from the same 

type of emission sources that are present 

in the pharmaceutical source category. 

We reviewed the regulatory 

requirements and/or technical analyses 

for these 10 regulations for new 

practices, processes, and control 

techniques. We also conducted a search 

of the BACT/RACT/LAER clearinghouse 

for controls for VOC- and HAP-emitting 

processes in the Pharmaceuticals source 

category. 

We identified no advancements in 

practices, processes, and control 

technologies applicable to the emission 

sources in the Pharmaceuticals 

Production source categories in our 

technology review. 

5. Printing and Publishing Industry 

In the twelve years since the Printing 

and Publishing NESHAP was 

promulgated, EPA has developed three 

air toxics regulations that emit organic 

HAP from emission sources that are 

similar to those addressed in the 

Printing and Publishing NESHAP. We 

reviewed the regulatory requirements 

and/or technical analyses associated 

with each of three subsequent regulatory 

actions to identify any practices, 

processes, and control techniques 

considered in these efforts that could 

possibly be applied to the Printing and 

Publishing Industry source category. We 

also conducted a search of the BACT/ 

RACT/LAER clearinghouse for permits 

dating back to 1990 for controls for 

VOC- and HAP-emitting processes in 

the Printing and Publishing Industry 

and four additional source categories 

with emission sources similar to those 

in the Printing and Publishing Industry 

source category. 

In addition to these two sources of 

information, we obtained information 

directly from the printing and 


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publishing industry and the closely 

related paper, film, and foil coating 

industry regarding developments in 

practices, processes, or controls. 

We identified no advancements in 

practices, processes, and control 

technologies applicable to the emission 

sources in the Printing and Publishing 

source category in our technology 

review. 

II. Proposed Action 

We propose that each of the five 

MACT standards for the nine source 

categories evaluated in RTR Group 2A— 

Epichlorohydrin Elastomers Production, 

HypalonTM Production, Nitrile 

Butadiene Rubber Production, 

Polybutadiene Rubber Production, and 

Styrene Butadiene Rubber and Latex 

Production, Marine Vessel Loading 

Operations, Mineral Wool Production, 

Pharmaceuticals Production, and the 

Printing and Publishing Industry— 

provide an ample margin of safety to 

protect public health and adverse 

environmental effect. Thus, we are 

proposing to re-adopt each of these 

standards for purposes of meeting the 

requirements of CAA section 112(f)(2). 

In addition, we propose that there are 

no developments in practices, 

processes, or control technologies that 

support revision of the five MACT 

standards pursuant to CAA section 

112(d)(6). 

A. What is the rationale for our 

proposed action under CAA Section 

112(f)? 

Section 112(f) of the CAA requires 

that EPA promulgate standards for a 

category if promulgation of such 

standards is required to provide an 

ample margin of safety to protect public 

health or to prevent, taking into 

consideration costs, energy, safety, and 

other relevant factors, an adverse 

environmental effect. The approach we 

use to make this determination is that 

set forth in the preamble to the Benzene 

NESHAP. First, we exclusively evaluate 

health risk measures and information in 

determining whether risks are 

acceptable. Second, we may consider 

costs and other factors in deciding 

whether further emission reductions are 

necessary to provide an ample margin of 

safety to protect public health. The EPA 

is not required to promulgate standards 

for a source category under CAA section 

112(f) if the emissions standards protect 

public health with an ample margin of 

safety and prevent an adverse 

environmental effect. 

We determined for the printing and 

publishing industry that the maximum 

individual cancer risks were less than 1- 

in-1 million to the individual most 

exposed, and that emissions were 

unlikely to cause other adverse human 

health or environmental effects. For the 

other eight source categories addressed 

in this proposal, Epichlorohydrin 

Elastomers Production, Hypalon TM

Production, Nitrile Butadiene Rubber 

Production, Polybutadiene Rubber 

Production, Styrene-Butadiene Rubber 

and Latex Production, Marine Vessel 

Loading Operations, Mineral Wool 

Production, and Pharmaceuticals 

Production, we determined that 

maximum individual cancer risks were 

between 1-in-1 million and 100-in-1 

million to the individual most exposed. 

Because the risks to the individual most 

exposed are greater than 1-in-1 million 

for these source categories, we 

considered whether the existing 

NESAHP provides an ample margin of 

safety to protect public. In doing so, we 

took into account chronic non-cancer 

risks, acute risks, and environmental 

risks. For each of these eight source 

categories, we evaluated one or more 

control options and considered the cost 

of such controls, the emission 

reductions that would achieve and the 

impacts of those options on public 

health. We determined that the existing 

NESHAP for each source category 

provides an ample margin of safety to 

protect public health and prevents 

adverse environmental effects. 

Therefore, we determined that changes 

to the NESHAP are not required to 

satisfy section 112(f) of the CAA. This 

finding considers the additional costs of 

further control compared with the 

relatively small reductions in health 

risks achieved by the options for further 

control for each source category. 

B. What is the rationale for our 

proposed action under CAA Section 

112(d)(6)? 

As explained in section I.F. of this 

preamble, there have been no significant 

developments in practices, processes, or 

control technologies since promulgation 

of the NESHAP. Because there have 

been no such significant developments 

and because existing standards provide 

an ample margin of safety to protect 

public health, we conclude that no 

further revisions to the standards 

affected by this proposal are needed 

under section 112(d)(6) of the CAA. 

III. Request for Comments 

We request comment on all aspects of 

the proposed action. All significant 

comments received during the comment 

period will be considered. In addition to 

general comments on the proposed 

actions, we are also interested in 

additional data to reduce the 

uncertainties of the risk assessments. 

Comments must provide supporting 

documentation in sufficient detail to 

allow characterization of the quality and 

representativeness of the data or 

information. 

The facility-specific data for each 

source category are available for 

download on the RTR Web page at 

http://www.epa.gov/ttn/atw/rrisk/

rtrpg.html. The nine source categories 

affected by this proposal are referred to 

as Group 2A of RTR Phase 2. These data 

files include detailed information for 

each emissions release point at each 

facility in the source category. For large 

integrated facilities with multiple 

processes representing multiple source 

categories, it is often difficult to clearly 

distinguish the source category to which 

each emission point belongs. For this 

reason, the data available for download 

for each source category include all 

emission points for each facility in the 

source category, though only the 

emission points marked as belonging to 

the specific source category in question 

were included in the analysis for that 

source category. 

The data files for each source category 

must be downloaded from the RTR Web 

page to be viewed (http://www.epa.gov/ 

ttn/atw/rrisk/rtrpg.html). These are 

Microsoft Access files, which require 

Microsoft Access to be viewed (if you 

do not have Microsoft Access, contact 

us by e-mail at RTR@epa.gov). Each file 

contains the following information from 

the NEI for each facility in the source 

category: 

Facility data Emissions data 

EPA Region .............................................................................................. Pollutant Code. 

Tribal Code ............................................................................................... Pollutant Code Description. 

Tribe Name ............................................................................................... HAP Category Name. 

State Abbreviation .................................................................................... Emissions (TPY). 

Control Measure in Place (Y/N). 

County Name ............................................................................................ MACT Code. 

State County FIPS .................................................................................... MACT Source Category Name.


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Facility data Emissions data 

NEI Site ID ................................................................................................ MACT Flag. 

Facility Name ............................................................................................ MACT Compliance Status Code. 

Location Address ...................................................................................... SCC Code. 

City Name ................................................................................................. SCC Code Description.

State Name ............................................................................................... Emission Unit ID. 

Zip Code ................................................................................................... Process ID. 

Facility Registry Identifier ......................................................................... Emission Release Point ID.

State Facility Identifier .............................................................................. Emission Release Point Type Code. 

SIC Code .................................................................................................. Emission Release Point Type. 

SIC Code Description ............................................................................... Stack Default Flag. 

NAICS Code ............................................................................................. Stack Default Flag Description. 

Facility Category Code ............................................................................. Stack height. 

Facility Category ....................................................................................... Exit Gas Temperature. 

Stack Diameter. 

Exit Gas Velocity. 

Exit Gas Flow Rate. 

Fugitive Length. 

Fugitive Width. 

Fugitive Angle. 

Longitude. 

Latitude. 

Location Default Flag. 

Data Source Code. 

Data Source Description. 

HAP Emissions Performance Level Code. 

HAP Emissions Performance Level Description. 

Start Date. 

End Date. 

More information on these NEI data 

fields can be found in the NEI 

documentation at http://www.epa.gov/

ttn/chief/net/2002inventory.html#

documentation. 

IV. How do I submit suggested data 

corrections? 

If you believe that the data are not 

representative or are inaccurate, please 

identify the data in question, provide 

your reason for concern, and provide 

improved data, if available. When 

submitting data, we ask that you 

provide documentation of the basis for 

the revised values to support any 

suggested changes. 

To submit comments on the data 

downloaded from the RTR Web page, 

complete the following steps: 

1. Within this downloaded file, enter 

suggested revisions in the data fields 

appropriate for that information. The 

data fields that may be revised include 

the following: 

Facility data Emissions data 

REVISED Tribal Code .............................................................................. REVISED Emissions (TPY). 

REVISED County Name ........................................................................... Emissions Calculation Method Code. 

REVISED Facility Name ........................................................................... REVISED MACT Code. 

REVISED Location Address ..................................................................... REVISED SCC Code. 

REVISED City Name ................................................................................ REVISED Emission Release Point Type. 

REVISED State Name .............................................................................. REVISED Start Date. 

REVISED Zip Code .................................................................................. REVISED End Date. 

REVISED Facility Registry Identifier ........................................................ REVISED Pollutant Code. 

REVISED Control Measure in Place (Y/N). 

Control Measure. 

REVISED Facility Category Code ............................................................ REVISED Stack height. 

REVISED Exit Gas Temperature. 

REVISED Stack Diameter. 

REVISED Exit Gas Velocity. 

REVISED Exit Gas Flow Rate. 

REVISED Longitude. 

REVISED Latitude. 

North American Datum. 

REVISED HAP Emissions Performance Level. 

2. Fill in the following commenter 

information fields for each suggested 

revision: 

• Commenter Name 

• Commenter Organization 

• Commenter E-Mail Address 

• Commenter Phone Number 

• Revision Comments 

3. Gather documentation for any 

suggested emissions revisions (e.g., 

performance test reports, material 

balance calculations, etc.). 

4. Send the entire downloaded file 

with suggested revisions in Microsoft 

Access format and all accompanying 

documentation to Docket ID No. EPA– 

HQ–OAR–2008–0008 (through one of 

the methods described in the ADDRESSES

section of this preamble). To answer 

questions on navigating through the 


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data and to help expedite review of the 

revisions, it would also be helpful to 

submit revisions to EPA directly at 

RTR@epa.gov in addition to submitting 

them to the docket. 

5. If you are providing comments on 

a facility with multiple source 

categories, you need only submit one 

file for that facility, which should 

contain all suggested changes for all 

source categories at that facility. 

We strongly urge that all data revision 

comments be submitted in the form of 

updated Microsoft Access files, which 

are provided on the http://www.epa.gov/ 

ttn/atw/rrisk/rtrpg.html Web page. Data 

in the form of written descriptions or 

other electronic file formats will be 

difficult for EPA to translate into the 

necessary format in a timely manner. 

V. Statutory and Executive Order 

Reviews 

A. Executive Order 12866: Regulatory 

Planning and Review 

Under Executive Order 12866 (58 FR 

51735, October 4, 1993), this action is a 

significant regulatory action. This action 

is a significant regulatory action because 

it raises novel legal and policy issues. 

Accordingly, EPA submitted this action 

to the Office of Management and Budget 

(OMB) for review under Executive 

Order 12866 and any changes made in 

response to OMB recommendations 

have been documented in the docket for 

this action. 

B. Paperwork Reduction Act 

This action does not impose any new 

information collection burden. This 

action is proposing no changes to the 

existing regulations affecting the nine 

source categories affected by this 

proposal and will impose no additional 

information collection burden. 

C. Regulatory Flexibility Act 

The Regulatory Flexibility Act (RFA) 

generally requires an agency to prepare 

a regulatory flexibility analysis of any 

rule subject to notice and comment 

rulemaking requirements under the 

Administrative Procedure Act or any 

other statute unless the agency certifies 

that the rule will not have a significant 

economic impact on a substantial 

number of small entities. Small entities 

include small businesses, small 

organizations, and small governmental 

jurisdictions. 

For purposes of assessing the impact 

of this rule on small entities, small 

entity is defined as: (1) A small business 

as defined by the Small Business 

Administration’s regulations at 13 CFR 

121.201; (2) a small governmental 

jurisdiction that is a government of a 

city, county, town, school district, or 

special district with a population of less 

than 50,000; and (3) a small 

organization that is any not-for-profit 

enterprise which is independently 

owned and operated and is not 

dominant in its field. 

After considering the economic 

impact of this rule on small entities, I 

certify that this action will not have a 

significant economic impact on a 

substantial number of small entities. 

This proposed rule will not impose any 

requirements on small entities. EPA is 

proposing no further action at this time 

to revise the NESHAP. 

We continue to be interested in the 

potential impacts of the proposed rule 

on small entities and welcome 

comments on issues related to such 

impacts. 

D. Unfunded Mandates Reform Act 

This proposed rule contains no 

Federal mandates under the provisions 

of Title II of the Unfunded Mandates 

Reform Act (UMRA), 2 U.S.C. 1531– 

1538 for State, local, or tribal 

governments or the private sector. The 

rule imposes no enforceable duty on 

State, local, or tribal governments, or the 

private sector. Therefore, this proposed 

rule is not subject to the requirements 

of sections 202 or 205 of the UMRA. 

This proposed rule is also not subject 

to the requirements of section 203 of the 

UMRA because it contains no regulatory 

requirements that might significantly or 

uniquely affect small governments 

because it contains no requirements that 

apply to such governments nor does it 

impose obligations upon them. 

E. Executive Order 13132: Federalism 

Executive Order 13132, entitled 

Federalism (64 FR 43255, August 10, 

1999), requires EPA to develop an 

accountable process to ensure 

meaningful and timely input by State 

and local officials in the development of 

regulatory policies that have federalism 

implications. ‘‘Policies that have 

federalism implications’’ is defined in 

the Executive Order to include 

regulations that have substantial direct 

effects on the States, on the relationship 

between the national government and 

the States, or on the distribution of 

power and responsibilities among the 

various levels of government. 

This proposed rule does not have 

federalism implications. It will not have 

substantial direct effects on the States, 

on the relationship between the national 

government and the States, or on the 

distribution of power and 

responsibilities among the various 

levels of government, as specified in 

Executive Order 13132. None of the 

facilities in the RTR Group 1 source 

categories are owned or operated by 

State governments, and, because no new 

requirements are being promulgated, 

nothing in this proposal will supersede 

State regulations. Thus, Executive Order 

13132 does not apply to this proposed 

rule. 

In the spirit of Executive Order 13132, 

and consistent with EPA policy to 

promote communications between EPA 

and State and local governments, EPA 

specifically solicits comment on this 

proposed rule from State and local 

officials. 

F. Executive Order 13175: Consultation 

and Coordination With Indian Tribal 

Governments 

This proposed rule does not have 

tribal implications, as specified in 

Executive Order 13175 (65 FR 67249, 

November 9, 2000). It will not have 

substantial direct effect on tribal 

governments, on the relationship 

between the Federal government and 

Indian tribes, or on the distribution of 

power and responsibilities between the 

Federal government and Indian tribes, 

as specified in Executive Order 13175. 

Thus, Executive Order 13175 does not 

apply to this rule. 

EPA specifically solicits additional 

comment on this proposed rule from 

tribal officials. 

G. Executive Order 13045: Protection of 

Children From Environmental Health 

Risks and Safety Risks 

The proposed rule is not subject to 

Executive Order 13045 (62 FR 19885, 

April 23, 1997) because it is not 

economically significant as defined in 

Executive Order 12866, and because the 

Agency does not believe the 

environmental health or safety risks 

addressed by this action present a 

disproportionate risk to children. This 

action’s health and risk assessments are 

contained in section I.D., E., and F. of 

this preamble. 

H. Executive Order 13211: Actions 

Concerning Regulations That 

Significantly Affect Energy Supply, 

Distribution, or Use 

This proposed rule is not a 

‘‘significant energy action’’ as defined in 

Executive Order 13211, (66 FR 28355, 

May 22, 2001) because it is not likely to 

have a significant adverse effect on the 

supply, distribution, or use of energy. It 

does not impose any new energy 

requirements. Further, we have 

concluded that this rule will not have 

any adverse energy effects. 


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I. National Technology Transfer and 

Advancement Act 

Section 12(d) of the National 

Technology Transfer and Advancement 

Act of 1995 (NTTAA), Public Law 104– 

113, 12(d) (15 U.S.C. 272 note) directs 

EPA to use voluntary consensus 

standards (VCS) in its regulatory 

activities, unless to do so would be 

inconsistent with applicable law or 

otherwise impractical. VCS are 

technical standards (e.g., materials 

specifications, test methods, sampling 

procedures, and business practices) that 

are developed or adopted by VCS 

bodies. NTTAA directs EPA to provide 

Congress, through OMB, explanations 

when the Agency decides not to use 

available and applicable VCS. 

The proposed rulemaking does not 

involve technical standards. Therefore, 

EPA is not considering the use of any 

VCS. 

J. Executive Order 12898: Federal 

Actions To Address Environmental 

Justice in Minority Populations and 

Low-Income Populations 

Executive Order 12898 (59 FR 7629, 

February 16, 1994) establishes Federal 

executive policy on environmental 

justice. Its main provision directs 

Federal agencies, to the greatest extent 

practicable and permitted by law, to 

make environmental justice part of their 

mission by identifying and addressing, 

as appropriate, disproportionately high 

and adverse human health or 

environmental effects of their programs, 

policies, and activities on minority 

populations and low-income 

populations in the United States. 

EPA has determined that this 

proposed rule will not have 

disproportionately high and adverse 

human health or environmental effects 

on minority or low-income populations 

because it does not affect the level of 

protection provided to human health or 

the environment. This proposed rule 

would not relax the control measures on 

sources regulated by the rule and, 

therefore, would not cause emissions 

increases from these sources. 

List of Subjects in 40 CFR Part 63 

Environmental protection, 

Administrative practice and procedures, 

Air pollution control, Hazardous 

substances, Intergovernmental relations, 

Reporting and recordkeeping 

requirements. 

Dated: September 29, 2008. 

Stephen L. Johnson, 

Administrator. 

[FR Doc. E8–23373 Filed 10–9–08; 8:45 am] 

BILLING CODE 6560–50–P 


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