9450 Federal Register / Vol. 76, No. 33 / Thursday, February 17, 2011 / Rules and Regulations 

ENVIRONMENTAL PROTECTION 

AGENCY 

40 CFR Parts 9 and 63 

[EPA–HQ–OAR–2010–0239; FRL–9242–3] 

RIN 2060–AP48 

National Emission Standards for 

Hazardous Air Pollutants: Gold Mine 

Ore Processing and Production Area 

Source Category; and Addition to 

Source Category List for Standards 

AGENCY: Environmental Protection 

Agency (EPA). 

ACTION: Final rule. 

SUMMARY: EPA is adding the gold mine 

ore processing and production area 

source category to the list of source 

categories to be regulated under Section 

112(c)(6) of the Clean Air Act due to its 

mercury emissions. EPA is also 

promulgating national emission 

standards for hazardous air pollutants to 

regulate mercury emissions from this 

source category. 

DATES: This final rule is effective on 

February 17, 2011. The incorporation by 

reference of certain publications listed 

in the final rule is approved by the 

Director of the Federal Register as of 

February 17, 2011. 

ADDRESSES: EPA has established a 

docket for this action under Docket ID 

No. EPA–HQ–OAR–2010–0239. All 

documents in the docket are listed on 

the http://www.regulations.gov Web 

site. Although listed in the index, some 

information is not publicly available, 

e.g., Confidential Business Information 

(CBI) or other information whose 

disclosure is restricted by statute. 

Certain other material, such as 

copyrighted material, is not placed on 

the Internet and will be publicly 

available only in hard copy form. 

Publicly available docket materials are 

available either electronically through 

www.regulations.gov or in hard copy at 

the EPA Headquarters Library, Room 

Number 3334, EPA West Building, 1301 

Constitution Ave., NW., Washington, 

DC. The EPA/DC Public Reading Room 

hours of operation are 8:30 a.m. to 4:30 

p.m. Eastern Standard Time (EST), 

Monday through Friday. The telephone 

number for the Public Reading Room is 

(202) 566–1744, and the telephone 

number for the Air and Radiation 

Docket and Information Center is (202) 

566–1742. 

FOR FURTHER INFORMATION CONTACT: Mr. 

Chuck French, Sector Policies and 

Program Division, Office of Air Quality 

Planning and Standards (D243–02), 

Environmental Protection Agency, 

Research Triangle Park, North Carolina 

27711, telephone number (919) 541– 

7912; fax number (919) 541–3207, 

e-mail address: french.chuck@epa.gov. 

SUPPLEMENTARY INFORMATION: The 

information presented in this preamble 

is organized as follows: 

I. General Information 

A. Does this action apply to me? 

B. Where can I get a copy of this 

document? 

C. Judicial Review 

II. Addition to Section 112(c)(6) Source 

Category List 

III. What is the statutory authority and 

regulatory approach for the proposed 

standards? 

IV. Summary of Significant Changes Since 

Proposal 

A. Applicability 

B. Final Emission Standards 

C. Compliance Dates 

D. Compliance Requirements 

E. Monitoring Requirements 

F. Definitions 

V. Summary of Responses to Major 

Comments 

A. Statutory Requirements 

B. Applicability 

C. MACT Floors 

D. Compliance Determinations 

E. Monitoring Requirements 

F. Definitions 

VI. Summary of Environmental, Economic 

and Health Benefits 

VII. 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 

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 

K. Congressional Review Act 

I. General Information 

A. Does this action apply to me? 

The regulated categories and entities 

potentially affected by this final rule 

include: 

Category NAICS code 1 Examples of regulated entities 

Industry: 

Gold Ore Mining ........... 212221 Establishments primarily engaged in developing the mine site, mining, and/or beneficiating (i.e., 

preparing) ores valued chiefly for their gold content. Establishments primarily engaged in 

transformation of the gold into bullion or dore bar in combination with mining activities are included in this industry. 

1 North American Industry Classification System. 

This table is not intended to be 

exhaustive, but rather provides a guide 

for readers regarding entities likely to be 

affected by this action. To determine 

whether your facility would be 

regulated by this action, you should 

examine the applicability criteria in 40 

CFR 63.11640 of subpart EEEEEEE 

(National Emission Standards for 

Hazardous Air Pollutants (NESHAP): 

Gold Mine Ore Processing and 

Production Area Source Category). If 

you have any questions regarding the 

applicability of this action to a 

particular entity, consult either the air 

permit authority for the entity or your 

EPA Regional representative, as listed in 

40 CFR 63.13 of subpart A (General 

Provisions). 

B. Where can I get a copy of this 

document? 

In addition to being available in the 

docket, an electronic copy of this final 

action will also be available on the 

Worldwide Web (WWW) through the 

EPA Technology Transfer Network 

(TTN). Following signature, a copy of 

this final 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. 

C. Judicial Review 

Under Section 307(b)(1) of the Clean 

Air Act (CAA), judicial review of this 

final rule is available only by filing a 

petition for review in the U.S. Court of 


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1The new test data used in final MACT standard 

calculations can be found in the docket as docket 

items: EPA–HQ–OAR–2010–0239–0359 and EPA– 

HQ–OAR–2010–0239–0360. 

2Analyses for the final MACT standards can be 

found in the docket in the document titled: 

‘‘Development of the MACT Floors and MACT for 

the Final NESHAP for Gold Mine Ore Processing 

and Production’’ (also known as the ‘‘MACT 

Development Document’’). 

Appeals for the District of Columbia 

Circuit by April 18, 2011. Under section 

307(d)(7)(B) of the CAA, only an 

objection to this final rule that was 

raised with reasonable specificity 

during the period for public comment 

can be raised during judicial review. 

Moreover, under section 307(b)(2) of the 

CAA, the requirements established by 

this final rule may not be challenged 

separately in any civil or criminal 

proceedings brought by EPA to enforce 

these requirements. 

Section 307(d)(7)(B) also provides a 

mechanism for us to convene a 

proceeding for reconsideration, ‘‘[i]f the 

person raising an objection can 

demonstrate to EPA that it was 

impracticable to raise such objection 

within [the period for public comment] 

or if the grounds for such objection 

arose after the period for public 

comment (but within the time specified 

for judicial review) and if such objection 

is of central relevance to the outcome of 

the rule.’’ Any person seeking to make 

such a demonstration to us should 

submit a Petition for Reconsideration to 

the Office of the Administrator, U.S. 

EPA, Room 3000, Ariel Rios Building, 

1200 Pennsylvania Ave., NW., 

Washington, DC 20460, with a copy to 

the person listed in the preceding FOR

FURTHER INFORMATION CONTACT section. 

II. Addition to Section 112(c)(6) Source 

Category List 

For reasons stated in the preamble to 

the proposed rule (75 FR 22470, April 

28, 2010), we are adding the gold mine 

ore processing and production area 

source category to the list of source 

categories under section 112(c)(6) on the 

basis of its mercury emissions. The 

preamble for the proposed rule provides 

a description of this industry including 

the processes used and the typical 

control technologies applied. 

III. What is the statutory authority and 

regulatory approach for the proposed 

standards? 

As explained in the preamble to the 

proposed rule, CAA section 112(c)(6) 

requires that EPA set standards under 

section 112(d)(2) or (d)(4). The mercury 

standards for the gold mine ore 

processing and production area source 

category are being established under 

CAA section 112(d)(2), which requires 

maximum available control technology 

(MACT) level of control. Under CAA 

section 112(d), the MACT standards for 

existing sources must be at least as 

stringent as the average emissions 

limitation achieved by the best 

performing 12 percent of existing 

sources (for which the administrator has 

emissions information) for source 

categories and subcategories with 30 or 

more sources, or the best performing 5 

sources for categories and subcategories 

with fewer than 30 sources (CAA 

section 112(d)(3)(A) and (B)). This level 

of minimum stringency is called the 

MACT floor. For new sources, MACT 

standards must be at least as stringent 

as the emission control that is achieved 

in practice by the best controlled similar 

source (CAA section 112(d)(3)). EPA 

also must consider more stringent 

‘‘beyond-the-floor’’ control options. 

When considering beyond-the-floor 

options, EPA must consider not only the 

maximum degree of reduction in 

emissions of HAP, but must take into 

account costs, energy, and nonair 

quality health and environmental 

impacts when doing so. 

IV. Summary of Significant Changes 

Since Proposal 

This section summarizes the 

significant changes to the rule since 

proposal. Additional information on the 

basis for these changes and other 

changes can be found in the Summary 

of Responses to Major Comments in 

section V of this preamble and in the 

Summary of Comments and Responses 

document which is available in the 

docket for this action. 

A. Applicability 

We have clarified in § 63.11651 of the 

final rule that the term ‘‘gold mine ore 

processing and production facility’’ does 

not include individual prospectors and 

very small pilot scale mining 

operations. These types of operations 

are very small and were not included in 

the section 112(c)(6) inventory that was 

the basis for the listing of the gold mine 

ore processing and production source 

category. 

B. Final Emission Standards 

We have made changes to all of the 

proposed emission standards as the 

result of the following developments: 

(1) Inclusion of additional emissions 

test data received since proposal; 1

(2) additional analyses in response to 

public comments on the proposed rule; 2

and (3) further review of the data used 

to develop the standards for the 

proposed rule. The changes are 

summarized below and described in 

more detail in section V of this 

preamble. We estimate the final MACT 

standards will reduce mercury 

emissions from gold mine ore 

processing and production down to a 

level of about 1,180 pounds per year, 

which will be an estimated 77 percent 

reduction from the 2007 emissions level 

(5,000 lb/yr), a 95 percent reduction 

from year 2001 emissions level (about 

23,000 lb/yr), and more than 97 percent 

reduction from uncontrolled emissions 

levels (more than 37,000 lb/yr). 

Ore Pretreatment Processes 

In the proposed rule, the proposed 

mercury emission standards for both 

existing and new ore pretreatment 

processes were 149 pounds per million 

tons of ore processed (lb/million tons of 

ore). In the final rule, the emission 

standard for existing sources is 127 lb/ 

million tons of ore; and for new sources 

the emission standard is 84 lb/million 

tons of ore. The final emission standards 

are based on several changes to the data 

set used in the MACT analysis. Since 

we issued the proposed rule, we 

collected emissions data from more 

recent tests that were not available at 

proposal. Further, we learned that two 

emissions tests that we used to develop 

the MACT floor in our proposed rule 

had been invalidated by the Nevada 

Division of Environmental Protection 

(NDEP), and we removed those test 

results from the database. Information 

on the specific tests invalidated and the 

rationale are available in the docket 

(docket item number EPA–HQ–OAR– 

2010–0239–0061). We also discovered 

that the test data for a unit within the 

ore pretreatment affected source at a 

facility should have been included as 

part of a different unit at the same 

facility. We have also dropped the data 

for one facility from the analysis 

because their autoclave was shut down 

in 2007 and dismantled, and the only 

test data we had for them was one test 

of the autoclave when it was operating 

in 2006. Moreover, we conducted 

additional beyond-the-floor analyses for 

the ore pretreatment affected source. 

The new information and analyses 

described above are discussed in more 

detail in section V.C of this preamble 

and in the MACT Development 

Document which is available in the 

docket for this rulemaking. 

The resulting data set included 

emissions data for four facilities that 

ranged from 45 to 165 lb/million tons of 

ore. Based on these data, and using the 

same upper prediction limit (UPL) 

approach used for proposal to account 

for variability, we determined the 

MACT floor to be 158 lb/million tons of 

ore for existing sources of ore 

pretreatment processes and 84 lb/ 


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million tons of ore for new sources. As 

explained in the proposed rule (75 FR 

at 22482), the technologies that we 

estimate are needed to achieve the 

MACT floor level of performance for 

existing ore pretreatment processes 

include calomel-based mercury 

scrubbers on roasters and venturi 

scrubbers on autoclaves and ancillary 

roaster operations. The preamble to the 

proposed rule provides a description of 

the UPL and the approach and 

calculations used to derive the UPL. The 

UPL is also discussed further in section 

V. 

In our beyond-the-floor analysis, we 

evaluated the potential to add 

condensers and carbon adsorbers to 

control autoclaves, and the potential to 

add carbon adsorbers to control the ore 

pre-heaters. Based on this beyond-thefloor analysis, we concluded that it is 

feasible and cost-effective to establish 

the MACT standard for existing sources 

at a level lower than the MACT floor. 

Based on the analysis, we determined 

the MACT standard for existing sources 

to be 127 lb/million tons of ore. For new 

sources, we determined that it was not 

feasible and cost-effective to establish a 

standard lower than the new source 

MACT Floor (of 84 lb/million tons); 

therefore the MACT standard for new 

sources was determined to be 84 lb/ 

million tons. 

The technologies needed to achieve 

the new source MACT floor will depend 

on the types of ore processed, amount 

of mercury in the ore, and specific 

process units used. Nevertheless, we 

conclude that, at a minimum, the 

controls that would be needed would 

include calomel-based mercury 

scrubbers on roasters and venturi 

scrubbers on autoclaves and ancillary 

roaster operations. Additional controls 

that will likely be needed to achieve 

emissions at or below the new source 

MACT floor level include condensers 

and carbon adsorbers on autoclaves, and 

carbon adsorbers on ore preheaters. 

Table 1 summarizes the MACT floor 

analysis for existing and new ore 

pretreatment processes. The beyond-thefloor analyses are explained further in 

section V of this preamble and in more 

detail in the MACT Development 

document. 

TABLE 1—MACT FLOOR RESULTS FOR

ORE PRETREATMENT PROCESSES

Facility 

Average 

performance 

(lb/million 

tons of ore) 

A ............................................. 45 

C ............................................. 56 

E ............................................. 71 

TABLE 1—MACT FLOOR RESULTS FOR

ORE PRETREATMENT PROCESSES— 

Continued 

Facility 

Average 

performance 

(lb/million 

tons of ore) 

D ............................................. 165 

Average of the 4 facilities ....... 84 

99% UPL for existing sources 

(i.e., the MACT Floor for existing sources) ..................... 158 

99% UPL for new sources 1

(i.e., the MACT Floor for 

new sources) ....................... 84 

1The MACT Floor for new sources is based 

on the average performance of Facility A (i.e., 

45) plus an amount to account for variability 

(i.e., 45 + 39 = 84). 

Carbon Processes 

Under the proposed rule, all carbon 

processes were subject to the same 

proposed mercury emissions limits of 

2.6 pounds per ton of concentrate (lb/ 

ton of concentrate) for existing sources 

and, for new sources, either 0.14 lb/ton 

of concentrate or 97 percent reduction 

in uncontrolled mercury emissions. 

These limits would have applied to 

facilities that operate mercury retorts 

and facilities that do not operate 

mercury retorts. In the final rule, we 

distinguish between carbon processes 

with mercury retorts and carbon 

processes without mercury retorts 

because we believe there are unique 

differences in these two types of 

processes. Therefore, the final rule 

specifies separate emission standards 

for these two types of processes. 

Moreover, the final emission standards 

for carbon processes reflect inclusion of 

new test data that were not available at 

proposal. We also revised our data set 

based on new information that we 

received since proposal which impacted 

which sources were among the best 

performing sources. Based on the data 

that we have, there are 10 facilities that 

have carbon processes with mercury 

retorts, and we have mercury emissions 

data for all 10 of these facilities. There 

are approximately 7 facilities that have 

carbon processes without mercury 

retorts, and we have comprehensive and 

reliable mercury emissions data for 2 of 

these facilities. These 2 facilities are the 

best controlled facilities within that 

group based on the information we 

have. (See section V for further details.) 

For carbon processes with mercury 

retorts, the emission standard in the 

final rule is 2.2 lb/ton of concentrate for 

existing sources and 0.8 lb/ton of 

concentrate for new sources. For carbon 

processes without mercury retorts, the 

emission standard in the final rule is 

0.17 lb/ton of concentrate for existing 

sources and 0.14 lb/ton of concentrate 

for new sources. 

For carbon processes, regardless of 

whether the facility operates a mercury 

retort, we estimate that to meet the 

MACT floor facilities would generally 

need to have mercury condensers and 

carbon adsorbers to control mercury 

emissions. We also considered beyondthe-floor options for both existing and 

new sources for these process groups, 

which were based on the addition of a 

second carbon adsorber; however, we 

rejected those options because they are 

not cost effective. Additional 

information on the analyses performed 

can be found in the MACT Development 

document in the docket for this 

rulemaking. 

We also eliminated in the final rule 

the compliance alternative of 97 percent 

reduction for new carbon processes. 

After reviewing the comments received 

on this proposed alternative standard 

and giving further consideration to the 

practicality of how it would be 

measured, we concluded that this 

option would be difficult to implement, 

particularly when multiple processes 

that are operated at different times vent 

to a single control device and stack. In 

addition, we have limited data 

supporting this compliance alternative. 

In proposing this alternative for 

comment, we had hoped to, but did not, 

receive additional data indicating that 

the 97 percent reduction option would 

be equivalent to the proposed new 

source limit of 0.14 pounds of mercury 

per ton of concentrate. For the reasons 

stated above, we eliminated the 97 

percent control efficiency option for 

new carbon processes in the final rule. 

Table 2 summarizes the results of the 

MACT floor analysis for carbon 

processes with mercury retorts, and 

Table 3 summarizes the analysis for 

carbon processes without mercury 

retorts. 

TABLE 2—MACT FLOOR RESULTS FOR

CARBON PROCESSES WITH MERCURY RETORTS

Facility 

Average 

performance 

(lb/ton of 

concentrate) 

N ........................................... 0 .53 

J ............................................ 0 .74 

I ............................................. 1 .06 

A ........................................... 1 .47 

H ........................................... 1 .67 

D ........................................... 2 .20 

C ........................................... 3 .71 

G ........................................... 8 .17 

E ........................................... 14 .49 

B ........................................... 20 .60 


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TABLE 2—MACT FLOOR RESULTS FOR

CARBON PROCESSES WITH MERCURY RETORTS—Continued 

Facility 

Average 

performance 

(lb/ton of 

concentrate) 

Average of top 5 ................... 1 .1 

99% UPL for existing 

sources (i.e., MACT Floor 

for existing sources) .......... 2 .2 

99% UPL for new sources 

(i.e., MACT Floor for new 

sources) ............................ 0 .8 

TABLE 3—MACT FLOOR RESULTS FOR

CARBON PROCESSES WITHOUT

MERCURY RETORTS

Facility 

Average 

performance 

(lb/ton of 

concentrate) 

M ........................................... 0 .058 

F ............................................ 0 .098 

Average of top 2 facilities ..... 0 .078 

99% UPL for existing 

sources (i.e., MACT Floor 

for existing sources) .......... 0 .17 

99% UPL for new sources 

(i.e., MACT Floor for new 

sources) ............................ 0 .14 

Non-Carbon Concentrate Processes 

Under the proposed rule, the mercury 

emission standards for non-carbon 

concentrate processes were 0.25 lb/ton 

of concentrate for existing sources and 

0.2 lb/ton of concentrate for new 

sources. In the final rule, the emission 

standards for these sources are 0.2 lb/ 

ton of concentrate for existing sources 

and 0.1 lb/ton of concentrate for new 

sources. These standards are based on 

using new emissions data that were not 

available when we developed the 

proposal, along with the data that were 

used for the proposal. For non-carbon 

concentrate processes, we estimate that 

to meet the MACT floors, for both 

existing and new sources, facilities 

would generally need to control 

mercury emissions using mercury 

condensers and carbon adsorbers. As 

explained in the proposed rule, we 

considered beyond-the-floor controls for 

these processes (which were based on 

adding a second carbon adsorber to the 

MACT floor level controls) but 

concluded those controls would not be 

a cost-effective option. There are 

approximately 3 facilities in the U.S. 

that use these types of processes. We 

have emissions tests data for 2 of these 

facilities. 

Table 4 summarizes the results of the 

MACT floor analysis for non-carbon 

concentrate processes. 

TABLE 4—MACT FLOOR RESULTS FOR

NON-CARBON CONCENTRATE PROCESSES

Facility 

Average 

performance 

(lb/ton of 

concentrate) 

K ........................................... 0 .047 

L ............................................ 0 .078 

Average of 2 facilities ........... 0 .062 

99% UPL for existing 

sources (i.e., MACT Floor 

for existing sources) .......... 0 .2 

99% UPL for new sources 

(i.e., MACT Floor for new 

sources) ............................ 0 .1 

C. Compliance Dates 

In the final rule, we provide in 

§ 63.11641 that the compliance date for 

existing sources is 3 years after 

promulgation of the final rule as 

opposed to 2 years as proposed. We 

reviewed the information provided in 

public comments on the challenges of 

installing new controls, especially for 

autoclaves, which, although the controls 

have not yet been demonstrated, have 

been proposed by facilities with 

autoclaves in their Nevada Mercury 

Control Program (NMCP) permit 

applications. We also considered the 

installation of new controls on the 

roaster preheaters, which also have not 

yet been demonstrated, but have been 

proposed by these facilities in their 

NMCP permit applications. We 

concluded that allowing 3 years for 

existing sources to comply is 

appropriate, given the complexity of the 

sources, the combinations of control 

devices that are needed in many cases, 

and the amount of time necessary for 

designing, installing, testing, and 

commissioning additional emission 

controls for mercury. 

D. Compliance Requirements 

Section 63.11646(a)(1) of the final rule 

does not include Method 30A, as was 

proposed, as an appropriate method for 

determining mercury concentration 

because it is not yet in general use. This 

paragraph further clarifies that the use 

of ASTM D6784–02 and Method 30B are 

allowed for compliance tests only if 

approved by the permit authority as 

opposed to automatically being allowed 

as in the proposal. The final rule also 

does not include the requirement to 

follow the acetone rinse procedures and 

the absence of cyclonic flow 

determination requirement, which were 

in subparagraphs (v) and (vi) 

respectively of our proposed 

§ 63.11646(a)(1). Method 29 already 

includes requirements for the acetone 

rinse, so there is no need to specify 

those procedures in the rule; and 

Method 1, which is required by the rule, 

addresses the issue of cyclonic flow. 

In § 63.11646(a)(2), we changed the 

minimum sample volume when Method 

29 is used to determine compliance 

from the proposed 60 dry standard 

cubic feet (dscf) to 30 dscf. We believe 

this volume is adequate for detecting 

mercury in the samples and determining 

mercury emissions for this industry. We 

have also expanded this section to 

address non-detect values. If the 

emission testing results for any of the 

emission points yield a non-detect 

value, the final rule requires that the 

minimum detection limit (MDL) be used 

to calculate the mass of emissions (in 

pounds of mercury) for that emission 

point that would subsequently be used 

in the calculations to determine if the 

source is in compliance with the MACT 

standard. If the resulting calculations 

indicate that mercury emissions are 

greater than the MACT emission 

standard, the owner or operator may 

repeat the mercury emissions testing 

one additional time for any emission 

point for which the measured result was 

below the MDL using procedures that 

produce lower MDL results. If this 

additional testing is performed, the 

results from that testing must be used to 

determine compliance. 

For sources with multiple emission 

units (e.g., two roasters) ducted to a 

common control device and stack, we 

have clarified in § 63.11646(a)(3) that 

compliance testing must either be 

performed with all affected emissions 

units in operation, if this is possible, or 

units must be tested separately. We also 

clarified that the establishment of 

operating limits for units that share a 

common stack can be based on 

emissions when all process units are 

operating together, or based on testing 

units separately. However, this 

requirement does not affect the 

frequency and schedule for monitoring, 

which are specified in the rule. If 

facilities have batch type processes that 

cannot be operated simultaneously, then 

the facility can test some or all of the 

units individually. 

In § 63.11646(a)(6) and (7), we clarify 

that the production data used in 

compliance determinations are based on 

full calendar months. For the initial 

compliance test, data for all the full 

calendar months between publication of 

the final rule and the initial compliance 

test must be used. This initial 

compliance determination must include 

at least one full month of production 


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data (e.g., hours of operation, and 

million tons of ore processed or tons of 

concentrate processed) including the 

month the test was conducted. For 

subsequent annual compliance tests, 

data for the 12 full calendar months 

prior to the annual compliance test must 

be used to demonstrate compliance. In 

addition, we clarify in paragraphs 

§ 63.11646(a)(5), (6) and (7) that 

compliance determinations are based on 

the number of 1-hour periods each 

process unit operates. By using the 1- 

hour period terminology, the final rule 

language is consistent with the 

terminology used in the General 

Provisions to part 63. 

Because the final rule does not 

include the 97 percent reduction option 

that was in § 63.11645(e)(2) of the 

proposed rule, we have removed from 

the final rule the compliance 

requirement for that option that was in 

§ 63.11646(b) of the proposed rule, 

which addressed testing the inlets and 

outlets for sources choosing that 

proposed option. 

E. Monitoring Requirements 

Section 63.11647(a) of the final rule 

includes an additional option for 

monitoring mercury emissions from 

roasters. The proposed rule specified 

two options for monitoring mercury 

emissions: Paragraph (a)(1) specified 

weekly sampling using PS 12B; and 

paragraph (a)(2) specified continuous 

monitoring using a mercury continuous 

emissions monitoring system (CEMS). In 

the final rule, we added paragraph (a)(3) 

to provide a third option of continuous 

sampling using PS 12B. In addition, 

paragraph (a)(1) in the final rule was 

changed to require sampling at least 

twice per month using either PS 12B or 

Method 30B rather than weekly. We 

believe that Method 30B is an 

acceptable alternative method for 

monitoring purposes and allows owners 

and operators more flexibility in how 

they monitor roaster emissions. We also 

believe that sampling twice per month 

coupled with extensive parametric 

monitoring of control devices (as 

explained below) is sufficient for the 

monitoring option in paragraph (a)(1). 

Section 63.11647(a)(4)(iii) of the 

proposed rule would have required 

additional compliance testing if the 

mercury concentration in the ore fed to 

the roaster was higher than any 

concentration measured in the previous 

12 months. We have removed this 

requirement from the final rule because 

it is not clear that the mercury content 

of the ore has a significant effect on the 

performance of mercury scrubbers 

applied to roasters, which are designed 

to handle and operate efficiently for a 

range of mercury inlet concentrations. 

In addition, condensers are used to 

recover liquid elemental mercury prior 

to the mercury scrubber, and any 

increase in mercury loading would 

likely result in an increase in the 

recovery of elemental mercury. 

The final rule incorporates several 

changes to § 63.11647(b), which 

addresses monitoring of calomel-based 

mercury scrubbers (i.e., mercury 

scrubbers) that are used to control 

emissions from roasters. The proposed 

rule required monitoring of the scrubber 

liquid flow, liquid chemistry, scrubber 

pressure drop, and scrubber inlet gas 

temperature hourly. The final rule does 

not include the requirement to monitor 

pressure drop across calomel-based 

scrubbers because we conclude that 

pressure drop is not related to mercury 

emission control performance by this 

type of control device. In addition, the 

final rule allows hourly monitoring of 

the line pressure in the scrubber liquid 

supply line as an alternative to hourly 

monitoring of scrubber liquid flow rate. 

Line pressure monitoring is already in 

practice at some facilities and provides 

the same type of information as does 

liquid flow rate. As was proposed, the 

final rule allows the operating limit for 

scrubber liquid flow rate (or line 

pressure) and inlet gas temperature to be 

based on the minimum flow rate (or line 

pressure) or maximum inlet gas 

temperature established during the 

initial performance test. It also includes 

two additional options for setting these 

operating limits: (1) Based on the 

manufacturer’s specifications if certain 

types of systems are designed to operate 

within a specified range of flow rates or 

temperatures; and (2) based on limits 

established by the permitting authority. 

If the facility chooses the option to 

establish the limits during initial 

compliance, the final rule requires the 

scrubber flow rate operating limit to be 

based on either the lowest value for any 

run of the initial compliance test or 10 

percent less than the average value 

measured during the compliance test 

and the inlet gas temperature operating 

limit to be based on either the highest 

value for any run of the initial 

compliance test or 10 percent higher 

than the average value measured during 

the compliance test. This requirement 

takes into account the fact that, although 

initially the system may exhibit little 

variability from test run to test run, the 

short-term variability in performance 

may increase with time. Additional 

discussion of these changes can be 

found in section V.E of this preamble 

and in the Summary of Public 

Comments and Responses document in 

the docket for this rulemaking. 

In response to comments, we have 

revised the requirements for corrective 

action following control device 

monitoring parameter exceedances 

specified in § 63.11647(d). Under the 

final rule, if the corrective actions taken 

following an exceedance do not result in 

the parameter value (e.g., liquid flow 

rate, line pressure, or inlet gas 

temperature) being returned to within 

the parameter range or limit within 48 

hours, a mercury concentration 

measurement must be made to 

determine if the operating limit for 

mercury concentration is being 

exceeded. The measurement must be 

performed and the concentration 

determined within 48 hours after the 

initial 48 hours, or a total of 96 hours 

from the time the parameter was 

exceeded. If the measured mercury 

concentration meets the operating limit 

for mercury concentration, the 

corrective actions are deemed 

successful. In addition, the owner or 

operator may request approval from the 

permitting authority to change the 

parameter range or limit based on 

measurements of the parameter at the 

time the mercury concentration 

measurement was made. If, on the other 

hand, the measured mercury 

concentration indicates the operating 

limit for mercury concentration is 

exceeded, the exceedance must be 

reported as a deviation within 24 hours 

to the permitting authority, and the 

facility must perform a compliance test 

(pursuant to § 63.11647(d)) within 40 

days to determine whether the source is 

in compliance with the MACT standard. 

We believe 40 days is appropriate 

because it may take 3 to 4 weeks to 

schedule and have the testing contractor 

on site, and, following completion of the 

test, another week or so to receive the 

final test results, and allows sufficient 

time to notify the permitting authority. 

We also removed the requirement that 

roasters must be shut down if a 

parameter is out of range. 

In § 63.11647(a)(1)(ii) of the final rule, 

we require these same corrective actions 

described above (i.e., measuring 

mercury concentration within 48 hours, 

reporting a deviation if the data show 

the operating limit was exceeded within 

24 hours, and conducting a compliance 

test within 40 days) for exceedances of 

mercury concentration operating limits 

indicated by the results of the twice 

monthly monitoring using PS 12B or 

Method 30B, CEMS, or continuous 

monitoring using PS 12B. In such cases, 

the owner or operator must use the 

results of the compliance test to 

determine if the ore pretreatment 


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process affected source is in compliance 

with the emission standard. If the 

source is determined to be in 

compliance, the owner or operator may 

use this compliance test to establish a 

new operating limit for mercury 

concentration for the roaster. We also 

removed the requirement that roasters 

must be shut down if the mercury 

concentration is out of range. 

In the final rule, § 63.11647(f)(1) 

requires monthly sampling of the 

exhaust stream of carbon adsorbers 

using Method 30B. The duration of 

sampling must be at least the minimum 

sampling time specified in Method 30B 

and up to one week. The proposed rule 

required a full week of such sampling, 

but, as pointed out by one of the 

commenters, breakthrough of the 

sampling trap from exhaust streams 

with high mercury concentrations could 

occur before a week had elapsed. 

Section 63.11647(f)(2) of the final rule 

clarifies that sampling of the carbon bed 

must be collected from the inlet and 

outlet of the bed. This paragraph also 

specifies that, for carbon adsorbers with 

multiple carbon columns or beds, the 

sampling should be performed in the 

first and last column or bed rather than 

at the inlet or outlet. 

We have deleted § 63.11647(f)(3) in 

the proposed rule, which allowed the 

carbon bed change-out rate to be 

determined based on historical data and 

the estimated life of the carbon. We 

have concluded that this method would 

not be adequate to ensure that 

breakthrough does not occur earlier than 

expected. 

We have clarified § 63.11647(h) with 

respect to the monitoring of scrubbers 

(other than the calomel-based mercury 

scrubbers described above). Under the 

final rule, owners or operators are 

required to monitor and record water 

flow rate (or line pressure) and scrubber 

pressure drop once per shift; they also 

must record any occurrences when the 

water flow rate (line pressure) or 

pressure drop are outside the operating 

range, take corrective actions to return 

the water flow rate (line pressure) or 

pressure drop back in range, and record 

the corrective actions taken. At 

proposal, the water flow rate and 

pressure drop were to be monitored 

continuously. However, measuring the 

water flow rate (line pressure) and 

pressure drop once per shift will 

provide two to three measurements per 

day, and we believe that is sufficient to 

assure proper operations of the wet 

scrubber, and thus assure compliance 

with the emission standards. We have 

also added the option of monitoring the 

line pressure in the scrubber liquid 

supply line as an alternative to 

monitoring scrubber liquid flow rate 

because line pressure monitoring is 

already in practice at some facilities and 

provides the same type of information 

as does liquid flow rate. As was 

proposed, the final rule allows the 

operating limit for water flow rate and 

pressure drop to be based on the 

minimum value during the initial 

performance test. It also includes two 

additional options for setting the 

operating limit: (1) Based on the 

manufacturer’s specifications; and (2) 

based on limits established by the 

permitting authority. We have also 

clarified that, for scrubbers on 

autoclaves, the pressure drop parameter 

range should be established from 

manufacturer’s specifications only. 

F. Definitions 

We have added a definition of carbon 

adsorber to § 63.11651 to clarify that 

this term, as used in the final rule, 

includes control devices consisting of a 

single fixed carbon bed, multiple carbon 

beds or columns, carbon filter packs or 

modules, and other variations of carbon 

adsorber design. 

The definition of ‘‘gold mine ore 

processing and production facility’’ in 

§ 63.11651 of the rule has been clarified 

to state that small operations, such as 

prospectors and very small pilot scale 

mining operations, that process or 

produce less than 100 pounds of 

concentrate per year are excluded from 

the source category. These prospectors 

and very small pilot-scale operations 

(that process at or below this level) were 

not included in the section 112(c)(6) 

inventory that was the basis for the 

listing of gold mine ore processing and 

production source category. These types 

of very small operations were not 

intended to be subject to the final rule, 

and we do not expect any significant 

emissions from them. We also clarified 

that the source category does not 

include facilities at which 95 percent or 

more of the metals produced are metals 

other than gold. For example, if other 

non-ferrous metals (such as copper, 

lead, nickel, or zinc) comprise 95 

percent or more of the product, the 

facility is not part of the gold ore 

processing and production source 

category. 

V. Summary of Responses to Major 

Comments 

A. Statutory Requirements 

1. Listing of the Gold Mine Ore 

Processing and Production Source 

Category Under Section 112(c)(6) 

Comment: One commenter stated that 

adding the gold mine ore processing and 

production category to the list of 

categories required by Clean Air Act 

(CAA) section 112(c)(6) was correct and 

required because gold mines accounted 

for a significant portion of the aggregate 

emissions of mercury in the baseline 

year (1990) and because they still do so 

today. Other commenters stated that 

EPA does not have the authority to list 

gold mining processing and production 

as a source category under section 

112(c)(6) and noted that section 

112(c)(6) requires EPA to list, by 1995, 

categories of sources that make up 90 

percent of the 1990 emissions for a 

subset of hazardous air pollutants 

(HAP), including mercury. The 

commenters said that EPA concluded its 

statutory listing obligation for mercury 

in 1998 with the publication of a list of 

source categories constituting 90 

percent of aggregate mercury emissions, 

and that gold mining was not included 

on that list in 1998. In addition, the 

commenters said that the CAA requires 

EPA to list all categories under section 

112(c)(6) by 1995 and complete issuance 

of standards for all listed sources by 

2000, a task that would be impossible if 

EPA had the authority to add source 

categories ad infinitum. 

Response: We appreciate the 

commenter’s support in listing the gold 

mine processing and production area 

source category pursuant to section 

112(c)(6). We disagree, however, with 

the commenters that assert that EPA is 

precluded from listing additional 

categories pursuant to section 112(c)(6). 

The commenters appear to be arguing 

that EPA is limited to a single listing 

opportunity under section 112(c)(6) and, 

having not listed gold mine ore 

processing and production in the initial 

1998 listing effort, EPA is now 

foreclosed from doing so. There is 

nothing in the language of section 

112(c)(6), however, that precludes EPA 

from listing additional source categories 

to the extent EPA determines that those 

categories are needed to meet the 90 

percent requirement in section 

112(c)(6). Indeed, the commenter’s 

reading is contrary to the fundamental 

purpose of section 112(c)(6). 

The core requirement of section 

112(c)(6) is that EPA ‘‘shall * * * list 

categories and subcategories of sources 

assuring that sources accounting for not 

less than 90 per centum of the aggregate 

emissions of each such pollutant’’ are 

subject to standards under either 

11217FE0(d)(2) or (d)(4). EPA 

reasonably interprets section 112(c)(6) 

as allowing it to revise the list to add 

categories, where, as here, it determines 

that it needs the additional categories to 

meet the 90 percent requirement in 

section 112(c)(6). Indeed, EPA has 

previously revised the section 112(c)(6) 


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list to add a source category, where EPA 

determined that category was needed to 

meet its 90 percent requirement for 

mercury. See 72 FR 74087 (Dec. 28, 

2007) (adding area source electric arc 

furnaces to the section 112(c)(6) list). 

As explained in the proposed rule, we 

have a 1990 baseline emissions 

inventory, and it is against this baseline 

that we assess compliance with the 90 

percent requirement for each of the 

pollutants specified in section 112(c)(6). 

EPA explained in the initial 1998 listing 

notice that it was using 1990 as the 

baseline year for assessing compliance 

with the 90 percent requirement. As 

EPA has developed emission standards 

for the sources included on the initial 

section 112(c)(6) list, it has acquired 

additional information on those sources 

and their emissions in 1990, which has 

resulted in some revisions to the 1990 

baseline emissions inventory estimates. 

These revisions resulted in the need to 

regulate an additional source category. 

See 72 FR 74087 (setting standards for 

area source electric arc furnaces). 

In addition to obtaining additional 

information concerning the source 

categories on the initial list, EPA has 

obtained additional information 

concerning the 1990 emissions of other 

sources. As explained in the preamble 

to the proposed rule, at the time of the 

initial section 112(c)(6) listing, there 

was very little available information on 

mercury emissions from gold mine ore 

processing and production. See 75 FR 

22471. Because EPA lacked emissions 

information on mercury emissions from 

this source category at the time of the 

listing decision, EPA was unable to 

estimate the 1990 baseline mercury 

emissions from the gold mine ore 

processing and production source 

category and include this category in the 

first listing effort. Based on information 

that became available after the initial 

listing, EPA now finds that regulation of 

the area source gold mine ore processing 

and production category is needed to 

meet the 90 percent requirement for 

mercury. 75 FR 22471. Under the 

commenters’ view, EPA cannot add any 

additional categories to the section 

112(c)(6) list following the initial listing. 

If true, EPA could not meet its section 

112(c)(6) obligation—a result Congress 

could not have intended. EPA 

reasonably interprets section 112(c)(6) 

in a manner that allows the Agency to 

achieve that provision’s core 

requirement. EPA repeats that it sees 

nothing in the language or purpose of 

section 112(c)(6) that precludes it from 

listing additional source categories as 

needed. 

Finally, Congress left to EPA’s 

discretion which categories and 

subcategories of sources to include on 

the section 112(c)(6) list. We have 

determined that we need the gold mine 

ore processing and production source 

category to meet the 90 percent 

requirement in section 112(c)(6) for 

mercury and are therefore now setting 

standards for that category. 

We also reject the comment that the 

task of completing standards by 2000 

would be impossible if EPA had the 

authority to add source categories. 

Nevertheless, EPA is under a court 

ordered deadline to complete section 

112(c)(6) standards by January 16, 2011. 

(Sierra Club v. EPA, Consolidated Case 

No. 01–1537, D.D.C). 

Comment: Some commenters claimed 

that EPA did not provide an adequate 

basis for its 1990 emissions estimate for 

gold mining processing and production. 

Specifically, they questioned EPA’s 

estimated emissions of 4.4 tons from 

this source category in the 1990 baseline 

year. 

Response: Although the commenters 

question EPA’s estimated emissions of 

4.4 tons from this source category in the 

1990 baseline year, they did not provide 

an alternative method for calculating 

such emissions or alternative data or 

assumptions that should be used. They 

also did not explain what they think the 

1990 baseline emissions should have 

been. EPA continues to maintain that its 

baseline emissions estimate is 

reasonable. The methodology EPA used 

to derive that estimate is described in 

docket item EPA–HQ–OAR–2010–0239– 

0175. 

Comment: Several commenters stated 

that Phase 2 permits under the Nevada 

Mercury Control Program (NMCP), 

which are scheduled for issuance by the 

end of 2010, will result in MACT-level 

controls on all thermal units at Nevada 

gold mines. According to the 

commenters, these permits are the 

culmination of a 7-year collaborative 

effort between NDEP and the gold 

mining industry to substantially reduce 

mercury emissions from gold mine 

processes. The commenters said that the 

proposal does not address how the 

NESHAP will result in reductions in 

mercury at gold mines in areas of the 

country other than Nevada, where the 

mercury content of the ore in gold 

mines is non-existent or only a fraction 

of the amount found in Nevada, and 

Nevada accounted for 99 percent of 

mercury emissions associated with gold 

mining operations in the United States. 

According to the commenters, this 

shows that if Nevada has an equivalent 

mercury control program for the gold 

mining industry, then there is nothing 

to be gained from imposing a Federal 

program, and if EPA acknowledges that 

the mines in Nevada are already well 

controlled, then the listing of gold 

mining and the promulgation of an 

additional layer of regulation at 

substantial cost to industry, but with 

little environmental benefit, is both 

legally indefensible and practically 

unsupportable. 

Response: As explained above, we are 

regulating the gold mine ore processing 

and production source category to meet 

the 90 percent requirement in section 

112(c)(6) for mercury and are therefore 

setting standards for that category. 

Based on our 1990 baseline inventory 

for section 112(c)(6) and other emissions 

information for subsequent years, we 

estimate that this industry was among 

the top ten highest emitting categories of 

mercury emissions in the U.S. in 1990 

and has remained in the top 10 since 

that time. Moreover, even though most 

emissions are from facilities located in 

Nevada, several commenters expressed 

serious concerns about the potential for 

mercury emissions from new gold mines 

in other States (e.g., Alaska). We share 

these concerns about potential 

emissions from new gold mine facilities. 

Finally, Congress left to EPA’s 

discretion which categories and 

subcategories of sources to include on 

the section 112(c)(6) list. We are 

regulating the gold mine ore processing 

and production source category to meet 

the 90 percent requirement in section 

112(c)(6) for mercury and are therefore 

now promulgating a Federal NESHAP 

for existing and new gold mine ore 

processing and production facilities. 

2. Emission Standards for HAP Other 

Than Mercury 

Comment: One commenter stated that 

CAA section 112(c)(6) provides that 

EPA must ‘‘list categories and 

subcategories of sources assuring that 

sources accounting for not less than 90 

percent of each [enumerated] pollutant 

are subject to standards under 

subsection (d)(2) or (d)(4) of this 

section.’’ The commenter also stated that 

the D.C. Circuit has held repeatedly that 

when EPA sets standards for a category 

or subcategory of sources under section 

112(d)(2), EPA has a statutory duty to 

set emission standards for each HAP 

that the sources in that category or 

subcategory emit (e.g., National Lime 

Ass’n v. EPA, 233 F.3d 625, 633–634 

(D.C. Cir. 2000)). The commenter 

concluded that when EPA sets 

standards for gold mines under section 

112(d)(2), as section 112(c)(6) requires it 

to do, EPA must set section 112(d)(2) 

emission standards for all the HAP that 

gold mines emit. 

The commenter said that EPA appears 

to believe that because gold mines are 


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3EPA acknowledges that major sources regulated 

under section 112 must be subject to MACT 

standards for all HAP emitted from the source 

category consistent with National Lime. 

needed only to reach the section 

112(c)(6) requirement of 90 percent for 

mercury and not for the other pollutants 

enumerated in section 112(c)(6), EPA’s 

only obligation under section 112(c)(6) 

is to set section 112(d)(2) standards for 

mercury. The commenter said that 

section 112(c)(6) expressly requires EPA 

to issue section 112(d)(2) standards for 

the ‘‘sources’’ in the categories listed 

under section 112(c)(6), not some subset 

of the pollutants that those sources emit, 

and that section 112(d)(2) standards 

must include emission standards for 

each HAP that a source category emits. 

The commenter continued by stating 

that nothing in the CAA exempts EPA 

from this requirement. The commenter 

concluded that, had Congress wished to 

give EPA discretion to set standards for 

only some of the pollutants emitted by 

a category listed under section 112(c)(6), 

it would have done so expressly. 

Response: EPA disagrees with the 

comment that, even though EPA lists a 

category under section 112(c)(6) due to 

the emissions of one or more HAP 

specified in that section, EPA must 

issue emission standards for all HAP 

(including HAP not listed in section 

112(c)(6)) that sources in that category 

emit. The commenter cited in support 

the opinion by the United States Court 

of Appeals for the DC Circuit in 

National Lime Ass’n v. EPA, 233 F.3d 

625, 633–634 (D.C. Cir. 2000)). The part 

of the National Lime opinion referenced 

in the comment dealt with EPA’s failure 

to set emission standards for certain 

HAPs emitted by major sources of 

cement manufacturing because the 

Agency found no sources using control 

technologies for those HAP. In rejecting 

EPA’s argument, the court stated that 

EPA has ‘‘a statutory obligation to set 

emission standards for each listed 

HAP.’’ Id. at 634. The Court noted the 

list of HAP in section 112(b) and stated 

that section 112(d)(1) requires that EPA 

‘‘promulgate regulations establishing 

emission standards for each category or 

subcategory of major sources * * * of 

hazardous air pollutants listed for 

regulation. * * *’’ Id. (Emphasis added). 

For the reasons stated below, we do not 

believe that today’s final rule is 

controlled by or otherwise conflicts 

with the National Lime decision. 

National Lime did not involve section 

112(c)(6). That provision is ambiguous 

as to whether standards for listed source 

categories must address all HAP or only 

the section 112(c)(6) HAP for which the 

source category was listed. Section 

112(c)(6) requires that ‘‘sources 

accounting for not less than 90 per 

centum of the aggregate emissions of 

each such [specific] pollutant are 

subject to standards under subsection 

(d)(2) or (d)(4).’’ This language can 

reasonably be read to mean standards 

for the section 112(c)(6) HAP or 

standards for all HAP emitted by the 

source. Under either reading, the source 

would be subject to a section 112(d)(2) 

or (d)(4) standard. 

The commenter insists that once a 

section 112(d)(2) standard comes into 

play, all HAP must be controlled (per 

National Lime). But this result is not 

compelled by the pertinent provision, 

section 112(c)(6). That provision is 

obviously intended to ensure controls 

for specific persistent, bioaccumulative 

HAP, and this purpose is served by a 

reading which compels regulation under 

section 112(d)(2) only of the HAP for 

which a source category is listed under 

section 112(c)(6), rather than for all 

HAP. 

The facts here support the 

reasonableness of EPA’s approach. Gold 

mine ore processing is an area source 

category listed under section 112(c)(6) 

for regulation under section 112(d)(2) 

solely due to its mercury emissions. 

There is special statutory sensitivity to 

regulation of area source categories in 

section 112. For example, an area source 

category may be listed for regulation 

under section 112 if EPA makes an 

adverse effects finding pursuant to 

Section 112(c)(3) or if EPA determines 

that the area source category is needed 

to meet its section 112(c)(3) obligations 

to regulate urban HAP or its section 

112(c)(6) obligations to regulate certain 

persistent bioaccumulative HAP. 

Therefore, unless an area source 

category emits a section 112(c)(3) urban 

HAP or a section 112(c)(6) HAP and 

EPA determines that such category is 

needed to meet the 90 percent 

requirement set forth in section 

112(c)(3) and (c)(6), findings related to 

adverse human health or environmental 

effects are required before EPA can 

regulate that area source category— 

findings EPA is unable to make for nonmercury HAP emitted from the gold 

mine ore processing and production 

source category at this time. Moreover, 

to the extent EPA lists an area source 

category pursuant to section 112(c)(3) 

(whether that finding is based on 

adverse effects to human health or the 

environment or a finding that the source 

is needed to meet the 90 percent 

requirement in section 112(c)(3), the 

statute gives EPA discretion to set 

generally available control technology 

(‘‘GACT’’) standards for such sources. 42 

U.S.C. 7412(d)(5). 

EPA does not interpret section 

112(c)(6) to create a means of 

automatically compelling regulation of 

all HAP emitted by area sources 

unrelated to the core object of section 

112(c)(6), which is control of the 

specific persistent, bioaccumulative 

HAP, and thereby bypassing these 

otherwise applicable preconditions to 

setting section 112(d) standards for area 

sources. Nor does National Lime 

address the issue, since the case dealt 

exclusively with major sources.3 233 F. 

3d at 633. Consequently, EPA disagrees 

with the comment that it is compelled 

to promulgate section 112(d)(2) MACT 

standards for all HAP emitted by gold 

mine ore processors. 

3. Emission Standards for Fugitive 

Emissions 

Comment: One commenter stated that 

gold mines have significant fugitive 

emissions of mercury, but that EPA did 

not propose standards for these 

emissions or mention them in its 

proposal. The commenter said that EPA 

has a statutory obligation to set 

standards for gold mine mercury 

emissions under section 112(d)(2) and 

(3), and must set emission standards for 

all the mercury emissions from the 

listed category. Another commenter 

described a recent preliminary study at 

two facilities in Nevada that found 

fugitive mercury air emissions from 

various non-point sources at those two 

mining operations such as from leach 

pads and tailings ponds. 

One commenter stated that means to 

control fugitive emissions are available, 

such as enclosing their leaching 

operations. By enclosing the leaching 

process, the commenter believes that 

mines could eliminate this source of 

fugitive emissions. The commenter also 

stated that mines should not send 

tailings into open tailing ponds, but into 

closed treatment facilities that would 

remove mercury and other HAP from 

the tailings and prevent their release to 

the air. The commenter recommended 

that EPA evaluate the use of sulfurbased complexing agents for removing 

mercury during cyanidization of gold. 

According to the commenter, research 

indicates that these products appear 

useful for substantially reducing 

mercury in process solution during heap 

leaching. 

Response: Due to the lack of 

information, we have not included 

fugitive mercury emissions at gold mine 

facilities in our 1990 baseline emission 

estimate (or in our more recent 

emissions estimates) for the gold mine 

ore processing and production area 

source category. Accordingly, these 

fugitive emissions are not part of the 


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source category we are listing and 

regulating in this final rule. Other than 

the recent preliminary research at two 

facilities, we have no data on fugitive 

mercury emissions at gold mine 

facilities. The recent preliminary 

research suggests that some fugitive 

emissions may be occurring at these 

facilities from large non-point sources 

such as tailings ponds, leach fields and 

waste rock piles. However, it is our 

understanding that this preliminary 

research has not yet been published or 

peer-reviewed. Thus, at this juncture, 

we do not have sufficient information 

on fugitive emissions. 

Furthermore, we have very little 

information on how these fugitive 

mercury emissions might be controlled. 

A few commenters suggested that 

certain compounds were available that 

may be useful for limiting these 

emissions. However, as far as we know, 

there has been no demonstration that 

these compounds would work 

effectively to limit the emissions, and 

we do not know the costs or potential 

adverse impacts of applying these 

chemicals. Therefore, we question the 

feasibility and practicality of applying 

these chemicals to limit fugitive 

mercury emissions from these non-point 

sources. We also question the feasibility 

and practicality of enclosing the 

leaching operations or the tailings 

ponds, as suggested by some 

commenters. 

As explained in the proposed rule, the 

gold mine ore processing and 

production area source category covers 

the thermal processes that occur after 

ore crushing, including roasting 

operations (i.e., ore dry grinding, ore 

preheating, roasting, and quenching), 

autoclaves, carbon kilns, 

electrowinning, preg tanks, mercury 

retorts, and furnaces. The data and 

calculations used to derive the 

estimated 4.4 tons of mercury emissions 

for this source category for the 1990 

baseline inventory for section 112(c)(6) 

reflect emissions from the thermal 

processes described above, and the final 

MACT standards address all of these 

processes. 

4. Major Source Determination 

Comment: One commenter noted that 

the proposal stated that the gold mining 

processing and production source 

category consists of only area sources; 

however, the proposal indicated that 

actual emissions of hydrogen cyanide 

(HCN) at a few facilities were near the 

major source threshold. The commenter 

concluded that EPA violates both the 

CAA and its own regulations by basing 

its evaluation of whether gold mines are 

major sources on their actual emissions 

instead of their potential emissions. 

The commenter further noted that the 

proposal requested comment on a 

certification process that would allow 

gold mines to avoid major source status 

whereby companies could certify that 

they are area sources by implementing 

certain ‘‘management practices’’ and 

then certifying to EPA that they had 

done so. The commenter stated that 

such a certification process would be 

unlawful in calculating a sources 

‘‘potential to emit’’ because the 

management practices are not ‘‘control 

equipment,’’ ‘‘restrictions on hours of 

operation or on the type or amount of 

material combusted, stored, or 

processed,’’ and would not be ‘‘federally 

enforceable.’’ 

Other commenters supported EPA’s 

conclusion and determination that the 

gold mines are area sources of HAP. 

According to the commenters, EPA’s 

methodology in making this 

determination was extremely 

conservative because EPA did not apply 

what the commenters believe to be a key 

correction factor. Application of this 

correction factor would have reduced 

the HCN emissions estimates from by 

approximately 40–50%. The 

commenters also stated that fence line 

testing at selected gold mine operations 

demonstrated that these levels of HCN 

were below all applicable public health 

standards. 

The commenters believe that, because 

the gold mines are area sources of HCN, 

they should not be subject to section 

112 work practice standards or newly 

developed certification requirements. 

The commenters noted that it is not 

technically practical to set systematic 

work practice standards to reduce HCN 

emissions for every gold mining 

operation to follow because each mine 

is unique in its mineralogy and cyanide 

leaching processes, and different 

process solution pH values are 

necessary to enhance gold recovery. 

The commenters explained that for 

economic, health, and safety reasons, 

they already implement work practice 

standards designed to minimize HCN. 

The commenter concluded that the 

combination of these work practice 

standards and the annual TRI reporting 

more than adequately ensure that gold 

mining operations will remain area 

sources of HCN. 

Response: Contrary to the assertions 

of one of the commenter’s, EPA did not 

state in the preamble to the proposed 

rule that the sources at issue had actual 

emissions ranging from 5 to 9 tons. By 

contrast, EPA stated that ‘‘a few facilities 

are close to the major source threshold 

due to hydrogen cyanide (HCN).’’ 75 FR 

22479. EPA failed to clarify in the 

preamble to the proposed rule that the 

range of 5 to 9 tons represented 

potential to emit calculations for the 

largest-emitting sources. Specifically, as 

explained in the document ‘‘Estimated 

Emissions of HCN from Gold Mine 

Facilities in the U.S.’’ (which is 

available in the docket for this 

rulemaking), EPA estimated the 

potential to emit for the five largest 

sources assuming that these sources 

would be operating every day of the 

year, 24 hours a day, at 100 percent of 

its current capacity. These assumptions 

and calculations resulted in a potential 

to emit estimate of 5 tons of HCN per 

year for the largest source. EPA then 

completed a second set of calculations, 

using the same assumptions (i.e., 

operating every day of the year, 24 

hours a day, at full capacity), but 

without applying the surface area 

correction factor, and those calculations 

resulted in a conservative potential to 

emit estimate of 9 tons of HCN per year 

for the largest source. The emission 

estimates for the remaining large 

facilities were all below 9 tons. 

The commenters correctly point out 

that in determining whether a source is 

a ‘‘major source’’ under CAA section 

112, we must consider the source’s 

potential to emit, as well as its actual 

emissions. See CAA section 112(a)(1) 

and 40 CFR 63.2. As noted above, we 

specifically examined the sources’ 

potential to emit and concluded that all 

sources’ potential to emit were below 

the major source thresholds. 

Some commenters allege that EPA 

significantly overestimated HCN 

emissions from the larger sources by not 

accounting for certain correction factors. 

They assert that if one were to account 

for the appropriate correction factors in 

developing the potential to emit values, 

HCN emissions would ‘‘range from 3.7– 

4.5 tpy for the larger mines compared to 

the 5–9 tpy estimate’’ (See document 

titled ‘‘PTE Emission Estimates for HCN’’ 

by the Nevada Mining Association, 

which is available in the docket for this 

action). Other commenters make a 

blanket, unsupported assertion that the 

Agency has underestimated HCN 

emissions from the source category 

because they believe that without the 

management practices currently 

employed by sources in the category, 

HCN emissions would exceed the major 

source thresholds at the larger sources. 

These latter commenters, however, 

made only conclusory statements and 

did not demonstrate that HCN emissions 

from the larger sources would exceed 

the major source thresholds if the 

management practices were not 

employed. 


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In sum, EPA has developed 

conservative estimates of the sources’ 

potential to emit HCN. At one end of the 

range EPA estimates potential emissions 

of 5 tons per year of HCN for the largest 

source, which is well below the major 

source threshold of 10 tons per year of 

a single HAP. At the other end of the 

range EPA estimates potential emissions 

of 9 tons per year for that same largest 

source, which is a conservative estimate 

and is still below the major source 

threshold. The emission estimates for 

the remaining large facilities were all 

below 9 tons. We understand that the 

sources at issue implement various 

management practices as part of their 

operations to minimize the use and 

emissions of cyanide to protect workers, 

to comply with Mine Safety and Health 

Administration (MSHA) standards, to 

comply with their agreements to the 

International Cyanide Code, and for 

economic reasons (to reduce operational 

and supply costs). We currently do not 

have sufficient information to explicitly 

quantify emissions reductions achieved 

through these management practices, 

but nothing in the record suggests that 

the facilities would be major sources if 

they failed to employ the management 

practices. Accordingly, we are taking 

final action today to list the gold mine 

ore processing and production area 

source category and regulate its mercury 

emissions pursuant to CAA section 

112(c)(6). 

Although not required, we intend to 

send letters to various Gold Mining 

Processing and Production companies 

pursuant to Section 114 of the Clean Air 

Act to confirm our conclusion that the 

sources’ potential to emit remain below 

major source thresholds. 

5. Title V Permit Exemption 

Comment: In the proposal preamble, 

EPA solicited comment on whether a 

title V exemption ‘‘is appropriate under 

section 502(a) for any particular sources 

in this category.’’ One commenter 

offered the following reasons for not 

exempting gold mines from title V 

permitting requirements: 

• EPA did not properly determine 

whether some or all sources in the 

category are major sources by 

determining each source’s potential to 

emit. 

• The CAA allows EPA to exempt 

area sources from title V permitting only 

if it establishes that compliance with the 

title V permitting requirements would 

be ‘‘impracticable, infeasible or 

unnecessarily burdensome.’’ However, 

EPA does not claim that such 

requirements are ‘‘impracticable,’’ 

‘‘infeasible,’’ or ‘‘unnecessarily 

burdensome’’ for gold mines. 

• It is feasible and within the gold 

mining companies’ financial means to 

comply with title V permitting 

requirements. 

The commenter believes that the text 

and legislative history of the CAA make 

plain that Congress intended ordinary 

citizens to be able to get emissions and 

compliance information about air toxics 

sources and to be able to use that 

information in enforcement actions and 

in public policy decisions on a State 

and local level. According to the 

commenter, Congress did not think that 

enforcement by States or other 

government entities was enough; if it 

had, Congress would not have enacted 

the citizen suit provisions. The 

commenter said that, if a source does 

not have a title V permit, it is difficult 

or impossible for a member of the public 

to obtain relevant information about its 

emissions and compliance status or to 

bring enforcement actions. The 

commenter stated that to the extent the 

informational and enforcement benefits 

provided by title V permits can be 

considered a burden, these benefits far 

outweigh that burden. 

The commenter also noted that title V 

provides important monitoring benefits 

and that title V permits are necessary to 

provide adequate monitoring. The 

commenter concluded by stating that 

the legislative history of the CAA shows 

that Congress did not intend EPA to 

exempt source categories from 

compliance with title V unless doing so 

would not adversely affect public 

health, welfare, or the environment; 

however, exempting gold mines from 

title V would adversely affect public 

health, welfare and the environment by 

depriving the public of important 

informational and enforcement benefits. 

One State agency commented that 

additional title V permitting would 

subject both the source and the State 

agency to additional resource burdens. 

The commenter points out that major 

sources of criteria pollutant emissions 

are currently subject to title V permit 

requirements in Nevada and that 

sources not subject to major source 

permitting requirements are subject to 

Nevada’s minor source permitting 

program. In addition, the NMCP 

requires all mining sources to obtain 

mercury-specific operating permits to 

construct. The commenter believes that 

these permit programs would provide a 

strong basis for implementing and 

enforcing any Federal MACT 

requirements for the gold mining 

industry, and there would be nothing 

gained by subjecting these sources to 

title V permitting. 

Several commenters stated that EPA 

should exercise its discretion and 

exempt the gold mine ore processing 

and production industry from the title V 

requirements as impracticable, 

infeasible, and unnecessarily 

burdensome. The commenters said that, 

in light of EPA’s findings in other 

similar rulemakings for area sources, the 

four factors set forth in the Exemption 

Rule support a finding that title V 

permitting is ‘‘unnecessarily 

burdensome’’ for the gold mine ore 

processing and production area source 

category. 

In discussing the first factor of the 

Exemption Rule, whether title V would 

result in significant improvements to 

the compliance requirements, the 

commenters said that the proposed 

NESHAP for the gold mine ore 

processing and production area source 

category includes extensive monitoring, 

recordkeeping, and reporting 

requirements that are more 

comprehensive than title V 

requirements. The commenters believe 

that Nevada regulations and permits 

provide an additional layer of 

compliance assurance on the Federal 

NESHAP that obviates the need for title 

V permitting. The commenters claimed 

that the additional layering of title V 

does not ‘‘significantly improve’’ upon 

the proposed and existing compliance 

requirements. 

Regarding the second factor in the 

Exemption Rule, whether title V 

permitting would impose significant 

burdens on the area source category and 

whether the burdens would be 

aggravated by any difficulty the sources 

may have in obtaining assistance from 

permitting agencies, the commenters 

said that there are extensive 

administrative burdens and costs 

associated with the title V permitting 

process, including mandatory activities 

that have been previously identified by 

EPA. The commenters claimed that 

many of the area source gold mines are 

owned and operated by small entities 

that are already required to comply with 

comprehensive State permitting 

requirements for mercury emissions and 

that requiring title V permits for them 

would result in resources being 

redirected away from more useful and 

necessary efforts. 

The commenters explained that the 

third factor in the Exemption Rule 

examines whether the costs of title V 

permitting for the area source category 

would be justified, taking into 

consideration any potential gains in 

compliance likely to occur for such 

sources. The commenters claim that 

there do not appear to be any gains in 

compliance to justify the additional 

costs that would be imposed on these 

area sources from title V permitting 


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based on the lack of significant 

improvements in compliance 

requirements and the substantial 

additional costs and burdens associated 

with title V compliance. 

The commenters noted that the fourth 

factor in the Exemption Rule analysis is 

whether there are implementation and 

enforcement programs in place that are 

sufficient to assure compliance with the 

NESHAP for the area source category, 

without relying on title V permits. The 

commenters claimed that the proposed 

rule includes all necessary monitoring 

to effectively implement its 

requirements, and the area sources for 

the gold mine ore processing and 

production are already permitted under 

State permit programs. According to the 

commenters, all non-title V sources in 

Nevada are required to hold ‘‘Class II’’ 

operating permits that must contain, 

among other things, all applicable 

emission limitations and standards. The 

commenters said that other States where 

gold mine ore processing and 

production area source are located 

either would be covered by a 

comparable delegated State air program 

or by EPA. 

The commenters stated that EPA 

regularly provides title V exemptions for 

area sources similar to gold mine ore 

processing and production area sources 

and cited examples from the past year. 

The commenters claim that the existing 

and proposed compliance and 

monitoring requirements for the gold 

mines are generally more stringent than 

those found in the other NESHAPs for 

which EPA has granted a title V permit 

exemption. 

The commenters stated that 

exempting the gold mine ore processing 

and production area source category 

from title V permitting will not 

adversely affect public health, welfare, 

or the environment because title V 

permits do not generally impose 

substantive air quality control 

requirements. According to the 

commenters, requiring title V permits 

also carries the potential of adversely 

affecting public health, welfare, or the 

environment by shifting State agency 

resources away from ensuring 

compliance with a program that is 

reducing mercury emissions from gold 

mines. 

The commenters stated that EPA 

should exempt the gold mine ore 

processing and production area source 

category from title V permitting 

requirements, and at a minimum, 

should exempt area source gold mines 

that are subject to Nevada’s 

comprehensive mercury control 

program. 

Response: After reviewing the 

comments, we continue to believe that 

it is appropriate that all gold mine ore 

processing and production facilities be 

required to obtain title V permits. Most 

of the other area source categories for 

which we have provided title V permit 

exemptions have hundreds or thousands 

of facilities that are mostly owned by 

small businesses. In contrast, there are 

an estimated 21 facilities that are subject 

to this final rule, and, based on our 

research and analyses, none of the 

facilities are owned by small businesses; 

most of these facilities are owned by 

large, and in some cases, multi-national, 

corporations. Therefore, we conclude 

that the argument of financial burden, 

which has supported title V exemption 

for other source categories, does not 

apply to the gold mining industry (see 

Economic and Small Business Analysis, 

which is available in the docket). 

Currently, it is our understanding that 

7 of the 21 facilities that will be subject 

to the final rule already have title V 

permits (5 in Nevada and 2 in other 

states). Further, there are approximately 

5 facilities in all other States (i.e., except 

Nevada) that do not currently have title 

V permits that will be subject to this 

final rule, so title V permitting will 

apply to no more than a few facilities in 

any one of these other States. Therefore, 

we do not believe the requirement for 

title V permitting will be overly 

burdensome to the permitting 

authorities in those States. Although 

there are more facilities in Nevada that 

will be subject to the final rule, as the 

commenters point out, Nevada already 

has an effective permitting system in 

place. Five of the 14 gold mine facilities 

in Nevada already have title V permits. 

Because of Nevada’s existing permitting 

system and experience with title V 

permitting, we do not think that it is an 

undue burden on the State of Nevada to 

require title V permits from the other 

gold mine facilities located within the 

State. We also think it is important for 

the public in States where these 

facilities are located to have access to 

emissions and monitoring data and the 

opportunity for public involvement in 

the permitting of these facilities that is 

provided by title V permitting. 

6. Reconstruction 

Comment: Several commenters 

believe it is appropriate to group under 

each of the umbrella ‘‘affected sources’’ 

all the equipment associated with each 

particular process in order to ensure a 

reasonable application of the 

reconstruction provisions found in the 

General Provisions. The commenters 

asked that EPA reaffirm that the 50 

percent fixed capital cost trigger for 

determining reconstruction would be 

measured against all equipment 

components needed for the defined 

processes, and that reconstruction at 

one affected source as defined in the 

standard will not affect or result in 

reconstruction at another affected 

source. 

The commenters also noted that the 

definition of ‘‘reconstruction’’ authorizes 

EPA to establish special provisions in a 

particular standard for the application 

of the reconstruction criteria to the 

affected source. The commenters said 

that the ‘‘carbon processes’’ affected 

source illustrates that the affected 

source can consist of several pieces of 

interconnected equipment that together 

constitute the process line, and it can be 

anticipated that production needs will 

give rise to the need to add more pieces 

of equipment to an existing carbon 

process line or even to install a whole 

new carbon process line. The 

commenters provided three examples: 

Adding a new component to an existing 

carbon processes group; construction of 

a new carbon group due to expansion at 

a facility that has an existing carbon 

group; and installation of new pollution 

control equipment. The commenter said 

that consideration of whether or where 

new MACT requirements should apply 

in these examples warrants the 

development of special reconstruction 

provisions in this standard, or EPA 

should clarify that the three examples 

would not be considered reconstruction 

under the proposed rule. 

The commenters asked that EPA 

either clarify that the three examples 

would not be considered reconstruction, 

or alternatively, add the following 

provisions to the proposed rule: (1) An 

addition of a new piece of equipment to 

address production requirements is not 

considered a reconstruction, (2) the 

expansion of a facility by the 

construction of a completely new 

process line will not be considered a 

reconstruction of an existing process 

line, and (3) the installation of air 

pollution control equipment to comply 

with this standard is not considered a 

reconstruction. 

Response: The determination of what 

constitutes a reconstruction is directly 

tied to the definition of the affected 

source and the definition of 

reconstruction in the part 63 General 

Provisions: 

Reconstruction, unless otherwise defined 

in a relevant standard, means the 

replacement of components of an affected or 

a previously nonaffected source to such an 

extent that: 

(1) The fixed capital cost of the new 

components exceeds 50 percent of the fixed 

capital cost that would be required to 


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construct a comparable new [affected] source; 

and 

(2) It is technologically and economically 

feasible for the reconstructed source to meet 

the relevant standard(s) established by the 

Administrator (or a State) pursuant to section 

112 of the Act. Upon reconstruction, an 

affected source, or a stationary source that 

becomes an affected source, is subject to 

relevant standards for new sources, including 

compliance dates, irrespective of any change 

in emissions of hazardous air pollutants from 

that source. 

For each of the four affected sources 

in the final rule, we have defined the 

affected source as the collection of 

processes associated within each 

affected source. Consequently, if one 

process within the affected source is 

upgraded or replaced with a new 

process, the 50 percent fixed capital cost 

criterion would be based on the fixed 

capital cost of replacing all processes in 

the affected source, not just the capital 

cost of the process being upgraded or 

replaced. For example, if a new carbon 

kiln is added to an existing group of 

carbon processes with mercury retorts, 

the capital cost of the new carbon kiln 

would be divided by the fixed capital 

cost of constructing a comparable new 

affected source containing all of the 

processes within the existing affected 

source of carbon processes with 

mercury retorts to calculate the percent 

for comparison to the 50 percent 

criterion. 

With regard to the scenario where a 

new carbon process with a mercury 

retort is installed, the affected source is 

defined as the collection of all 

applicable processes within the affected 

source, and because of this, a facility 

could not have two carbon processes 

with mercury retorts affected sources, 

such as the commenter suggested, where 

one group is new and the other is 

existing. For example, if a new group of 

carbon processes with mercury retorts is 

installed at a facility in addition to an 

existing group of carbon processes with 

mercury retorts, the two groups (all 

carbon processes with mercury retorts at 

the facility) collectively would be a 

single affected source. In this case, the 

fixed capital cost criterion would be 

based on the fixed capital cost of 

replacing the existing affected source 

with a comparable new affected source, 

and if the new processes exceed 50 

percent of that cost, all of the carbon 

processes with mercury retorts would be 

subject to the new source limit for 

carbon processes. There would not be 

separate and different emission 

standards for the two sets of carbon 

sources with mercury retorts (the older 

group and newer group) because the 

collection of all of these processes is the 

affected source. 

We do not see a necessity to provide 

criteria for this final rule that are 

different from the requirements in the 

General Provisions for determining what 

constitutes a reconstruction. We also 

think it is appropriate to exclude the 

cost of emission control equipment from 

the cost calculation for reconstruction 

determinations. 

B. Applicability 

Comment: Several commenters stated 

the rule should exempt individuals 

(prospectors), laboratories, small mining 

operations, and non-leaching 

operations. The commenters urged EPA 

to include in the final rule all of the 

following exemptions to avoid the 

problem of unintended regulation of 

sources that were not meant to be 

included in the source category: Gold 

mining operations that produce less 

than 100 pounds of concentrate per 

year, which would exempt analytical 

labs that perform small bench scale 

processing tests on gold ores; gold 

mining operations that do not leach or 

dissolve gold, which would exempt 

placer and other non-leaching operators, 

including both small commercial efforts 

as well as individual recreation-type 

prospectors; and gold mining operations 

that process less than 1,000 tons per 

year of gold ore, which would exempt 

certain small scale pilot plants and 

related testing operations. The 

commenters said that the exemptions 

suggested above will not reduce in any 

way the effectiveness of the proposed 

rule in controlling mercury emissions 

from the targeted larger mines, nor will 

they lead to increased mercury 

emissions, but they will exclude 

regulation of a large number of small 

operators who do not emit any 

significant mercury. 

Response: Section 63.11640(c) of the 

proposed rule provides that the 

emissions standards for this area source 

category do not apply to research and 

development facilities, as that term is 

defined under CAA section 112(c)(7). 

We did not receive any adverse 

comments concerning this provision, 

and are finalizing the provision in this 

rule. 

Further, as mentioned above in 

section IV, we are clarifying in this final 

rule that this area source category does 

not include individual prospectors and 

very small pilot scale mining 

operations. Prospectors and other very 

small pilot-scale operations (e.g., 

operations that produce or process less 

than 100 pounds of concentrate per 

year) are very small and were not 

included in the section 112(c)(6) 

inventory that was the basis for the 

listing of gold mine ore processing and 

production source category. We believe 

that emissions from the very small scale 

operations described above to be very 

minimal. 

By contrast, the commenter’s 

suggested 1,000 tons/yr ore threshold 

may include operations beyond the very 

small scale pilot operations discussed 

above. We believe that the 100 pounds 

of concentrate per year more 

appropriately reflect these very small 

scale operations. 

We are not making the suggested 

change of excluding operations that do 

not leach or dissolve gold because 

certain gold mine facilities in the source 

category use flotation or gravity flotation 

processes and perform thermal 

processing of concentrate in melt 

furnaces, which can have significant 

emissions of mercury. However, as 

mentioned above we are clarifying that 

this final rule does not apply to these 

very small scale operations. 

C. MACT Floors 

1. Consideration of Variability in 

Determining Floors 

Comment: One commenter 

acknowledged that EPA may consider 

variability in calculating the best 

sources’ performance, but stated that 

EPA’s method of considering variability 

seeks to assure that none of the sources 

among those identified as best 

performers would ever exceed the floor 

level. The commenter claims that such 

an approach ignores the reality that 

sources’ emission levels are largely 

within their control, and although a 

great deal of variability may be 

statistically conceivable if EPA chooses 

a high enough prediction limit (in this 

case the 99th percentile) that does not 

mean that a well-operated source 

actually would experience such 

variability. The commenter said that one 

of the main points of having emission 

standards is to ensure that sources not 

only deploy the appropriate control 

measures, but also use those control 

measures consistently to minimize 

emissions. 

The commenter said that using an 

upper prediction limit to set standards 

reflecting the statistical worst 

performance these sources could have 

in a purely statistical sense does not 

yield an accurate picture of the best 

sources actual performance, and it is 

especially arbitrary in the absence of 

any explanation of why EPA thinks that 

the relevant best sources’ performance 

would ever be so bad, other than the fact 

that it is statistically possible. 

Response: As described previously, 

the MACT floor limits are calculated 

based on the performance of the lowest 


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4Run-to-run variability is essentially within-test 

variability, and encompasses variability in 

individual runs comprising the compliance test, 

and includes uncertainties in correlation of 

monitoring parameters and emissions, and 

imprecision of stack test methods and laboratory 

analysis. 72 FR at 54877 (Sept. 27, 2007). Test-totest variability results from variability in pollution 

device control efficiencies over time. Test-to-test 

variability can be termed long-term variability. 72 

FR at 54878. 

emitting sources in each of the MACT 

floor pools. We ranked all of the sources 

for which we had data based on their 

emissions and identified the lowest 

emitting sources. 

As the commenter concedes, EPA can 

consider variability in assessing sources’ 

performance when setting MACT 

standards. See Brick MACT, 479 F.3d at 

881–82; and Mossville Envt’l Action 

Now v. EPA, 370 F.3d 1232, 1241–42 

(D.C. Cir 2004) (reaffirming that EPA 

can assess variability in determining the 

level of emissions control achieved by 

the best performing sources). 

Variability in facilities’ performance 

has various causes. One source of 

variability for these facilities is the 

differing mercury concentrations in the 

input materials. Another source of 

variability is due to normal variations in 

performance of the control devices for 

which both run-to-run and test-to-test 

variability must be accounted.4 A 

review of the run-by-run emissions data 

in the record shows that emission rates 

from one run to the next for welloperated sources can vary by as much 

as a factor of 8. We need to account for 

sources’ variability (both due to control 

device performance and variability in 

inputs) in assessing sources’ 

performance when developing 

technology-based standards. 

Accordingly, EPA accounts for variance 

in test data, between units, and among 

facilities when developing the MACT 

standard. 

In determining the MACT floor limits, 

we first determine the average emissions 

of the top performers based on available 

data. We then assess variability of the 

best performers by using a statistical 

formula designed to estimate a MACT 

floor level that is equivalent to the 

average of the best performing sources 

based on future compliance tests. 

Specifically, the MACT floor limit is an 

upper prediction limit (UPL) calculated 

with the Student’s t-test. The Student’s 

t-test has also been used in other EPA 

rulemakings (e.g., NESHAP for Cement 

Manufacturing, NSPS for Hospital/ 

Medical/Infectious Waste Incinerators, 

and NESHAP for Industrial, 

Commercial, and Institutional Boilers 

and Process Heaters) in accounting for 

variability. A prediction interval for a 

future observation is an interval that 

will, with a specified degree of 

confidence, contain the next (or some 

other pre-specified) randomly selected 

observation from a population. In other 

words, the prediction interval estimates 

what the upper bound of future values 

will be, based upon present or past 

background samples taken. The UPL 

consequently represents the value 

which we can expect the mean of future 

observations (i.e., emission test runs) to 

fall below within a specified level of 

confidence, based upon the results of an 

independent sample from the same 

population. In other words, if we were 

to randomly select a future test 

condition from any of these sources 

(e.g., average of 3 runs) we can be 99 

percent confident that the reported level 

will fall at or below the 99 percent UPL 

value. We note that the methodology 

accounts for both short-term and longterm variability and encompasses runto-run and test-to-test variability. 

For this rule, we used the 99 percent 

UPL analysis on the emissions data for 

the top performing sources to account 

for the variance. In the context of 

determining the MACT floor, the 99 

percent UPL represents the value below 

which the mean of future compliance 

tests (based on, for example, a 3-run 

average) would fall 99 percent of the 

time. A 99 percent level of confidence 

means that a facility, whose emissions 

are consistent with the best performing 

sources, has one chance in 100 of 

exceeding the emission standard. 

We believe that using the 99 percent 

UPL is appropriate for this rule. As 

noted above, this approach is consistent 

with several other previous 

rulemakings. It also makes sense from a 

practical standpoint. If we selected a 

lower number (e.g., 95 percent UPL) this 

would mean that a best performing 

source that is performing at the MACT 

level of control would potentially 

exceed the limit 5 percent of the time— 

which we do not believe is a reasonable 

approach for this rule. See Mossville, 

379 F.3d at 1241–42); see also 70 FR at 

59438 (Oct. 12, 2005) (explaining use of 

99th percentile). With regard to the 

commenter’s statement that no sources 

among the best performers would ever 

exceed the MACT standard, we believe 

this is incorrect. The commenter 

provided no basis for this statement, 

and we do not believe the commenter 

based this statement on an analysis of 

the variability in the data. 

We do not believe that the UPL 

analysis reflects the statistical worst 

performance the top five performing 

sources could have. The UPL 

calculation is dependent on the data 

that we have, and reflects the actual 

variability in the test data for the best 

performing sources. It does not reflect 

worst-case performance. We continue to 

believe that the UPL does yield an 

accurate picture of the best sources’ 

performance as best as possible with 

taking into account variance between 

the facilities, units at the facilities, and 

between test runs for the different units 

(including variability in input 

materials). 

Furthermore, although the average of 

several data sets may show a top 

performing source meeting the emission 

standard by a significant margin, the 

variability in emissions inherent in any 

one compliance test could easily 

indicate much higher emissions, and, in 

some cases, an exceedance of the 

emission standard. We continue to 

believe that the UPL analysis evaluated 

at 99 percent confidence is appropriate 

for this source category. 

Moreover, we believe the data we 

used to calculate the MACT standards 

are representative of the normal 

performance of the best performing 

sources for several reasons. First, the 

test results that we are using in our 

MACT database are tests conducted 

under Nevada’s mercury emission 

control program, and are conducted to 

determine whether a facility is in 

compliance with State requirements. 

Facilities typically try to perform as 

well as they can during such tests. State 

(and often EPA) permitting authority 

staff are notified before a performance 

test is conducted to provide an 

opportunity to attend and observe the 

test, and they often attend to ensure the 

source is operating properly and that the 

testing is performed according to the 

strict requirements in the codified test 

methods. 

Test reports are carefully reviewed by 

the permitting authority, and any failure 

to follow the test method or abnormal 

operation of a source is flagged. These 

data are usually invalidated, and 

invalidated tests are not used in our 

MACT standard calculations. For 

example, several tests from these 

facilities were invalidated by the NDEP 

because the specified testing procedures 

were not followed or the emission 

control device was not operating 

properly, and we have not used those 

results in our analysis for those reasons. 

We have collected additional data from 

test reports not available at the time of 

proposal, and one of those tests was 

invalidated because NDEP 

representatives discovered that the 

emission control device was not 

operating properly during the test. 

Therefore, we also did not use those test 

data. 

The commenter believes that floors 

must be set at the average emission level 


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achieved by the best performers when 

they are operating properly. We agree 

that the performance data characterizing 

the emission level achieved by the top 

performers must be data obtained when 

they are operating properly, and we 

believe that is the case for our current 

database for this source category. 

As described above, the MACT floor 

is based on the average performance of 

the top performers plus an amount to 

account for variability. We have 

appropriately developed a MACT 

standard based on emissions from the 

top 5 best performing sources that 

accounts for variability because, over an 

extended period of time, the emissions 

from each of these best performing 

facilities (even the best controlled) will 

vary above and below the facility 

average. For example, we expect that 

about half of the duration of the year the 

emissions from a best performing 

facility would be somewhat below their 

average and that about half of the 

duration of the year their emissions 

would be somewhat higher than their 

average. If we set the MACT limit 

exactly equal to the average emissions 

level achieved by the best performers 

(without accounting for variability), and 

we had a source that was performing at 

exactly the MACT level over the course 

of the year, the measured emissions 

level on roughly half the days of the 

year would suggest that the source is 

emitting at levels above the MACT limit, 

and on about half of the other days of 

the year the measured emissions level 

would suggest that the source is 

emitting at levels less than the MACT 

limit. We reasonably and appropriately 

accounted for variability in the data 

consistent with established statistical 

theory and practice and judicial 

precedent. Finally, ignoring variability 

of the best performing sources and using 

only the average performance would 

virtually guarantee that some of even 

the best performers would exceed the 

floor limit at least some of the time. 

Thus, we developed a MACT standard 

based on the average of the best 

performing sources that accounts for 

variability. We accomplished this by 

calculating the MACT standard from 

this average performance and 

accounting for variability by using the 

99 percent UPL. The specific 

calculations are presented in the MACT 

floor document in the docket for this 

rulemaking. Furthermore, we agree with 

the comment that one of the points of 

having emission standards is to ensure 

that sources not only deploy the 

appropriate control measures, but also 

use those control measures consistently 

to minimize emissions. We believe that 

the MACT standards established in this 

rule along with the requirements to 

monitor and maintain control device 

parameters within certain ranges will 

ensure control measures are applied 

consistently to minimize emissions. 

Comment: Another commenter stated 

that consideration should be given to 

defining the inherent range of 

measurement error and requiring more 

test runs in order to reduce variability 

due to process variation. The 

commenter said that this would also 

better clarify when variability was due 

to operational controls, which could be 

addressed, rather than due to factors 

that cannot be controlled, such as 

mercury content in the ore. The 

commenter asked for clarification on 

how inconsistent runs should be 

treated, what defines an acceptable set 

of runs, and at what point more runs 

would be required to provide reliable 

data. 

The commenter also stated that the 

degree of variability allowed in the 

development of the new source limit for 

ore pretreatment appears to be out of 

line with the new source limits for 

carbon processes and non-carbon 

processes. The commenter believes that 

ore pretreatment variability for new 

sources is higher than existing sources 

because low thermal units were 

included in the same category, high 

emissions were allowed in the data set, 

and variable emissions were allowed in 

data set. The commenter recommended 

that, if EPA continues to use Goldstrike 

as the best performing source for new 

source MACT, then they should reevaluate and reduce the variability to be 

equal to or less than the variability for 

existing sources. 

Response: We agree with the 

commenter that the testing process 

would be more accurate if the number 

of test runs was increased. However, we 

balance several factors in determining 

the minimum number of runs required, 

and because the compliance testing is 

supplemented by various types of 

continuous or periodic parametric 

monitoring, we have concluded that 

three test runs are appropriate for this 

final rule. Although we have not 

proposed a formal procedure to assess 

the consistency of test runs, the 

permitting authority performs routine 

reviews of compliance test data to 

identify potential outliers and results 

that suggest further investigation is 

needed. For example, a routine review 

tracks trends in performance, and in 

particular, flags any trends in 

deteriorating performance over time. An 

unusually high run among the three 

runs also attracts attention and would 

be examined to determine if it might 

have been caused by a problem with the 

process, control device, sampling, or 

analysis. If the permitting authority 

identifies inconsistent runs, they have 

the authority to invalidate any or all 

runs. A source would be required to 

perform more runs to provide reliable 

data if two to three runs were 

invalidated. 

We agree with the commenter that the 

degree of variability used in the 

development of the proposed new 

source MACT standard for the ore 

pretreatment group appeared to be 

inconsistent with the degree of 

variability used in the development of 

the proposed new source MACT 

standard for carbon processes and noncarbon concentrate processes. We agree 

with the commenter that the ore 

pretreatment degree of variability at 

proposal for new sources was higher 

than the degree of variability for existing 

sources. We do not believe that the 

variability was higher because low 

thermal units (i.e., autoclaves) were 

included in the same category, but 

because two tests of the ore preheater/ 

dry grinding processes at Goldstrike 

were allowed in the data set. These tests 

had, as the commenter identified, 

inconsistently high emissions (as 

compared to other tests at other times 

for the same units) and inconsistent 

variability between the runs. We have 

determined that the tests the commenter 

is referring to are not representative of 

normal operation, and those tests have 

been removed from our database 

because the NDEP invalidated the tests 

due to possible sample contamination. 

(See the MACT Floor Document in the 

docket for the final rulemaking for more 

details). We continue to use Goldstrike 

as the best performing source for the ore 

pretreatment new source MACT, and 

the variability for new source MACT is 

now less than that of the variability for 

existing source MACT, and is less than 

the variability calculated at the time of 

proposal. 

2. General Comments on MACT 

Comment: Some commenters stated 

that the MACT floor already represents 

installation and operation of MACT 

controls, and the use of emissions data 

from facilities that are already 

controlling their mercury emissions 

creates an artificially low MACT floor. 

The commenters said that the low 

MACT floor penalizes facilities that 

voluntarily invested in pollution control 

technology and creates a substantial 

disincentive for industry and States to 

move ahead of EPA in reducing 

emissions of HAP. 

Response: We acknowledged at 

proposal that many gold mine facilities 

are already well controlled for many 


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reasons, including participation in the 

NMCP. We also acknowledge that the 

top performing facilities that are the 

basis for the MACT floor calculation are 

the top performers because they have 

installed controls. CAA section 

112(d)(3)(B) requires that, for a category 

with fewer than 30 sources, the MACT 

floor not be less stringent than ‘‘the 

average emission limitation achieved by 

the best performing 5 sources (for which 

the Administrator has or could 

reasonably obtain emission 

information).’’ (Emphasis added). EPA 

has information on the well-controlled 

facilities and used the information to 

conduct MACT floor analysis, as 

required by the CAA. Although the 

MACT floor may be considered more 

stringent in comparison to floors that 

would have been established if no 

facilities had mercury emission 

controls, we do not consider the floor to 

be ‘‘artificially low’’ because consistent 

with the statute, it reflects the level 

achieved in practice by the best 

performing sources. See 112(d)(3). We 

do not believe that the MACT floor 

penalizes facilities that invested in 

pollution control technology because 

those facilities will be able to meet the 

MACT standards. We do not consider 

that this final rule creates a disincentive 

for industry and States to move ahead 

of EPA in reducing HAP emissions 

because as facilities reduce mercury 

emissions by adding controls required 

by State programs, they will be able to 

meet the NESHAP. Most of the facilities 

that will not meet the current final 

standards have already proposed to add 

controls to their units in their Phase 2 

applications for the NMCP. 

3. MACT for the Ore Pretreatment 

Group 

Comment: Several commenters 

supported EPA’s general approach to 

establish three groups of affected 

sources in the proposal. On the other 

hand, several commenters suggested 

that EPA develop separate emission 

standards for roasters and autoclaves for 

existing and new sources. One 

commenter stated that roaster and 

autoclave processes are different from 

each other based on the mercury species 

released, controls utilized, and their 

rates of mercury emissions. The 

commenter said that roasters commonly 

reach temperatures of 400° to 700°C, 

releasing gaseous elemental mercury, 

whereas autoclaves commonly reach 

temperatures of 175° to 230°C producing 

reactive gaseous mercury and sulfate 

and forming mercury sulfate. According 

to the commenter, autoclaves are 

expected to be able to improve 

efficiency over time. The commenter 

noted that roasters produce one to two 

orders of magnitude higher emissions 

than do autoclaves. The commenter 

believes that facilities that only use 

autoclaves should not be allowed the 

leeway to emit at the rate that facilities 

employing roasters are allowed. The 

commenter recommends that the ore 

pretreatment group be divided into high 

temperature pretreatment processes 

(roasters) and low temperature 

pretreatment processes (autoclaves and 

ancillary roaster processes, such as dry 

grinding, pre-heating, and quenching). 

Response: We discussed in section 

V.A. of the preamble to the proposed 

rule our rationale for establishing the 

different affected sources, including the 

ore pretreatment processes affected 

source. We believe it is appropriate to 

maintain the ore pretreatment group 

affected source, as we had proposed. We 

do not agree with the comment that 

roasters necessarily have higher 

emissions that are one to two orders of 

magnitude higher than emission from 

autoclaves. The available data show a 

wide range in emissions from autoclaves 

(from 0.4 to 115 lb/million tons of ore). 

This range overlaps the range for 

roasters and their ancillary equipment, 

which have combined emissions 

between 42 to 71 lb/million tons of ore. 

Regardless of the mercury species 

released, controls utilized, operating 

temperatures, or control efficiency over 

time, autoclaves and roasters process 

the same input material (i.e., ore) and 

are intended for the same purpose (i.e., 

to oxidize the ore). Therefore, we 

believe that it is appropriate to maintain 

the ore pretreatment affected source as 

we had proposed, keeping roasting 

operations and autoclaves together. 

Comment: One commenter stated that 

EPA failed to consider beyond-the-floor 

standards for roasters and that if 

additional reductions are achievable at 

roasters, then EPA must set additional 

beyond-the-floor standards for roasters. 

A commenter also stated that 

although EPA’s standard for new ore 

pretreatment facilities is as high as its 

standard for existing facilities, EPA does 

not propose or discuss setting beyondthe-floor standards for new sources. The 

commenter claims that EPA has a 

statutory obligation to ensure that its 

new source standards reflect the 

maximum achievable reduction in 

emissions. 

Response: Following proposal, we 

continued to investigate the 

performance of facilities with ore 

pretreatment processes and 

opportunities for additional control. We 

collected data from more recent tests 

that were not available at proposal, and 

these new data show that emission 

control performance at these facilities 

has continued to improve. We identified 

two previous tests in the proposal 

database that were suspect, and we 

confirmed with NDEP that these tests 

should be invalidated and not used in 

the analysis because of possible sample 

contamination. We have also dropped 

the data for one facility from the 

analysis because their autoclave was 

shutdown in 2007 and dismantled, and 

we only had one test of the autoclave 

when it was operating in 2006. For these 

reasons, we did not include data for that 

facility in the analysis, which is now 

based on the only four facilities 

currently operating. 

Based on the addition and change 

described above with respect to our 

available data, we revised the MACT 

floor analysis for the ore pretreatment 

processes. The revised MACT floor for 

existing sources decreased from 175 lb/ 

million tons at proposal to 158 lb/ 

million tons, and the new source MACT 

floor dropped from 163 lb/million tons 

to 84 lb/million tons. 

The MACT floor limit for existing ore 

pretreatment processes is based on the 

use of calomel-based mercury scrubbers 

on roasters and wet scrubbers on 

autoclaves and ancillary roaster 

operations. We conducted a beyond-thefloor analysis during the development of 

the proposed rule. The roasters were 

already equipped with very good 

mercury controls (condensers and 

calomel-based mercury scrubbers), and 

we did not identify any beyond-thefloor options for the roasters. However, 

we identified as a beyond-the-floor 

control for autoclaves the installation of 

both a refrigeration unit (or condenser) 

and a carbon adsorber. We continue to 

believe that the roasters stacks are well 

controlled, but since our proposal, we 

have identified a beyond-the-floor 

control option (carbon adsorption) for 

the ore pre-heaters/dryers (ancillary 

roaster operation) that could achieve 

additional emissions reductions of 

approximately 70 percent (or more) for 

those units. Two of the three facilities 

with roasters have already proposed in 

their NMCP Phase 2 permit applications 

to apply controls to their preheaters/ore 

dryers, and these two companies have 

submitted cost estimates for applying a 

carbon adsorption system. Using the 

cost estimates submitted by the affected 

facilities, we estimate the capital costs 

for control of roaster preheaters/dryers 

for the three facilities with roasters as $3 

million with a total annualized cost of 

$1.6 million per year. We also estimate 

a reduction of 118 lb/yr of mercury 

emissions would be achieved at an 

overall cost effectiveness of about 

$13,800 per pound of mercury. We 


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believe that these costs and cost 

effectiveness are reasonable. As required 

under CAA section 112(d)(2), we have 

also considered non-air quality health 

and environmental impacts and energy 

requirements of this additional control. 

We conclude that this is an acceptable 

beyond-the-floor control technology for 

existing roaster preheaters/ore dryers. 

Therefore, we included the beyond-thefloor control for ore preheaters/dryers, 

as well as the beyond-the-floor control 

for autoclaves, in determining the 

MACT standard in this final rule for 

existing sources of ore pre-treatment 

processes. After applying the 

appropriate variability analyses to the 

data, we determined that the MACT 

standard for existing sources is 127 lb/ 

million tons of ore. 

As mentioned above, we have revised 

the new source MACT floor. We also 

did a beyond-the-floor analysis for new 

sources in the ore pre-treatment 

processes group. However, we did not 

establish the MACT standard for new 

sources based on this beyond-the-floor 

analysis because we did not identify a 

feasible and cost-effective option to 

achieve reductions greater than the new 

source MACT floor. Therefore, for new 

sources of ore pretreatment processes, 

the MACT ‘‘floor’’ is the MACT standard 

for the affected source. The final new 

source MACT standard is 84 lb/million 

tons of ore, which is considerably more 

stringent compared to the proposed 

standard of 149 lb/million tons of ore 

and reflects the maximum achievable 

reduction in emissions. 

Comment: One commenter stated that 

the proposed estimated capital costs of 

$890,000 and total annualized cost of 

$720,000 for beyond-the-floor autoclave 

controls are not representative of actual 

costs of installing a refrigeration unit (or 

condenser) and a carbon adsorber on 

autoclaves. The commenter estimates 

that capital costs for autoclave controls 

will range from $18 million to at least 

$30 million, and annual operating costs 

could range from $2 million to $60 

million, depending on which controls, if 

any, are determined to be technically 

feasible. The commenter believes that 

based on these cost estimates, beyondthe-floor MACT controls would be cost 

prohibitive and are not justified for the 

ore pretreatment affected source group. 

Another commenter estimated that for 

the installation of carbon adsorbers on 

their autoclaves to control mercury 

emissions, the capital costs would range 

from $30 million to $35 million, annual 

operating costs would be $2 million per 

year, and the annual energy 

requirements would be 11,400 

megawatt-hours per year with an annual 

energy cost of $900,000. 

Response: After reviewing the new 

cost estimates provided by the 

commenters, we agree that capital and 

total annualized cost estimates of the 

beyond-the-floor controls on autoclaves 

in the proposal were underestimated. 

We evaluated the detailed cost estimate 

based on an engineering study for a 

carbon adsorption system provided by 

one of the commenters (see details in 

the comment above on capital, 

operating, and energy costs), and our 

review of these details indicates it to be 

a reasonable cost estimate and more 

representative. Therefore, we have used 

this estimate as the basis for our 

estimate of the costs of the beyond-thefloor mercury emission controls for 

autoclaves. Our revised estimates are 

that the capital cost for installing carbon 

adsorbers on autoclaves would be $29.3 

million, with a total annualized cost of 

$4.9 million per year, which would 

result in an estimated reduction of 431 

lb/yr of mercury emissions per year and 

an overall cost effectiveness of about 

$11,000 per pound of mercury. Based on 

these new costs and estimated 

reductions we conclude that the beyond 

the floor controls are affordable and 

justified for the ore pretreatment 

affected source. 

Comment: Several commenters noted 

that, at the proposed new source MACT 

limit of 149 pounds/million tons of ore, 

the proposed new source Donlin Creek 

Mine, located in Alaska, would be 

allowed to emit 3,200 lb/yr of mercury 

based on a projected production rate of 

22 million tons/yr of ore. 

Response: With respect to this 

proposed new gold mine in Alaska, the 

commenters’ estimate of 3,200 lb/yr of 

mercury emissions is inaccurate and a 

significant overestimate for a number of 

reasons. The two primary reasons are 

that, based on available information, if 

the facility is built, only an estimated 

15 percent of the ore mined will be 

processed in autoclaves (not 100 percent 

as assumed by the commenters), and 

that the commenters’ estimate is based 

on assuming that the average emissions 

level for the facility throughout the year 

would be at the maximum allowed at 

the proposed new source limit (149 lb/ 

million tons of ore), which has been 

significantly reduced since proposal. 

With the new source MACT standard 

in the final rule that is about two times 

more stringent (i.e., lower) than the 

proposed MACT standard, along with 

corrections described above, we 

estimate that far less than 3,200 lb/yr 

would be emitted from this new source 

if it is ever built. Assuming continuous 

operation for 365 days per year, an 

estimated 21.5 million tons/yr of ore 

mined, about 3.2 million tons/yr 

processed in autoclaves (15 percent), 

and assuming the source would emit at 

the average emission level used to 

calculate the revised new source MACT 

(45 lb/million tons of ore), we calculate 

that mercury emissions would be about 

144 lb/yr, which is about 5 percent of 

the estimate provided by the 

commenters. Considering that the 

facility has yet to go through the 

permitting process and that, if it is built, 

it will likely include emissions controls 

that would reduce the emissions below 

45 lb/million tons of ore, we believe 

that, if the facility is built, emissions 

would quite likely be lower than 

144 lb/yr. 

4. MACT for Carbon Processes 

Comment: Several commenters 

objected to including Facility M in the 

MACT floor determination for new and 

existing sources in the carbon processes 

affected source because it is not 

representative of, or similar to, other 

sources, because it has unusually low 

mercury concentrations in its ore, and 

no need for a retort to remove and 

recover mercury. They noted that, 

because the mercury content of the gold 

ore is fixed, the only way for other 

facilities to reduce emissions of mercury 

is to apply mercury emission controls, 

but, for many facilities, emission 

controls will not be enough to meet the 

proposed MACT standard. The 

commenters stated they were aware that 

the DC Circuit Court had constrained 

EPA’s discretion to set floors that fail to 

consider material inputs, but they said 

gold mines were different from the 

remanded source categories (brick kilns 

and cement kilns) because gold mining 

operations process very large quantities 

of ore, and the ore is the only material 

input that results in mercury emissions. 

The commenters stated that, in adopting 

section 112, Congress expressly 

cautioned EPA against setting standards 

that would require mining operations to 

change the ore used as essential 

feedstock. The commenters said that, by 

ignoring the mercury content in the ore 

being mined and processed at the 

facilities in the MACT floor 

determination, EPA is requiring 

facilities to consider the substitution of, 

or changes in, the ore that is processed 

because there is no other way to achieve 

the standard. The commenters 

recommended that EPA address, as a 

threshold matter, the differences in 

processing and emissions across 

facilities that result from the variable 

concentration of mercury in ore. The 

commenters recommended that Facility 

M not be considered the ‘‘best controlled 

similar source’’ for purposes of setting 

the new source MACT floor because the 


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facility is not similar to other sources. 

The commenters stated that, if EPA does 

not exclude from the source category 

facilities that do not use retorts to 

process concentrate, then they should 

subcategorize them. 

Response: After consideration of 

comments and a re-examination of the 

design of the facilities at issue, the 

emission controls, and other factors 

affecting emissions from the carbon 

processes at Facility M, we agree that 

this facility is quite different and unique 

compared to most other gold mine ore 

processing and production facilities, 

including other facilities in Nevada, in 

its carbon process. The difference is 

manifested in the processing train in 

that mercury retorts are not needed or 

used at Facility M to recover mercury. 

As the commenter notes, the CAA 

allows EPA to ‘‘distinguish among 

classes, types and sizes of sources 

within a category’’ in developing MACT 

emission standards, and gold mine 

facilities without mercury retorts are 

different in both class and type from 

those with mercury retorts. Accordingly, 

in the final rule, we identify and set 

separate MACT standards for these two 

different types of carbon processes: 

those that use mercury retorts; and 

those, such as the carbon process at 

Facility M, that do not use mercury 

retorts. 

As part of our re-analysis of the 

MACT floor and the MACT for sources 

that are in the carbon processes with 

mercury retorts group and sources that 

are in the carbon processes without 

mercury retorts group, we considered 

new data that were not available at the 

time of proposal. Over the past one to 

two years since our data collection effort 

for the proposal, facilities in Nevada 

have continued to add controls and 

improve emission control as part of the 

NMCP. The new data indicate there 

were two facilities with carbon 

processes without mercury retorts 

operating in 2009. Using the data from 

these two facilities, we determined that 

the MACT floor limits for carbon 

processes without mercury retorts are 

0.17 lb/ton of concentrate for existing 

sources and 0.14 lb/ton of concentrate 

for new sources (based on the best 

performing facility, Facility M). 

In our beyond-the-floor analysis, we 

considered the addition of a carbon 

adsorber on an uncontrolled emission 

unit within an existing affected source. 

We estimate the capital cost as $210,000 

with a total annualized cost of $72,000 

per year, an emission reduction of 1.63 

lb/yr of mercury, and a cost 

effectiveness of $44,000/lb of mercury. 

We do not believe that the small 

emission reduction that this control 

option would achieve is justified in 

light of its cost. We therefore decided 

not to go beyond-the-floor. We also 

considered possible beyond-the-floor 

options for new carbon processes 

without mercury retorts, but concluded 

these options were not cost-effective or 

feasible. Therefore, for new and existing 

sources of carbon processes without 

mercury retorts, the MACT floor limit is 

the MACT standard for this affected 

source. 

As part of our re-analysis for the 

carbon group processes with mercury 

retorts, we collected and evaluated 

additional data. As discussed above, 

several of the facilities have improved 

emission control over the levels 

observed in the database we used at 

proposal. Two facilities with newlyinstalled controls replaced two higheremitting facilities that were in the top 5 

at proposal, and all three of the other 

facilities that remained in the top 5 had 

lower levels of emissions after 

considering the new data. The results 

are that the MACT floor limits for 

carbon processes with mercury retorts 

are 2.2 lb/ton of concentrate for existing 

sources and 0.8 lb/ton of concentrate for 

new sources (based on the best 

performing facility, Facility N). In the 

beyond-the-floor analysis, we evaluated 

the impacts of adding a second carbon 

adsorber in series with the controls 

applied to achieve the MACT floor level 

of control. We estimate the capital cost 

would be $3 million with a total 

annualized cost of $1.3 million per year, 

an emission reduction of 9 lb/yr of 

mercury, and a cost effectiveness of 

$150,000/lb of mercury. Because of the 

small emission reduction and high cost 

effectiveness associated with this 

additional control, we decided not to go 

beyond the floor. Therefore, for existing 

sources of carbon processes with 

mercury retorts, the MACT floor limit is 

the MACT standard for this affected 

source. We also considered possible 

beyond-the-floor options for new carbon 

processes with mercury retorts, but 

concluded these options were not costeffective or feasible. 

5. Compliance Alternative for New 

Carbon Process Sources 

Comment: One commenter noted that 

the compliance ‘‘alternative’’ of 97 

percent would be unlawful unless EPA 

specified that carbon sources had to 

meet the more stringent of either the 

floor standard or a 97 percent reduction 

standard. The commenter stated that 

because floors must reflect the emission 

level achieved by the best performing 

sources, allowing sources to meet a 97 

percent reduction standard that was less 

stringent than the emission level 

actually achieved by the relevant best 

sources would contravene section 

112(d)(3) and well-established D.C. 

Circuit court precedent. 

One commenter supported EPA’s use 

of the percent control alternative to the 

new source MACT for the carbon group. 

The commenter believes that the 

percent control alternative for new 

source carbon group MACT should also 

be available as an alternative to the 

existing source MACT for the carbon 

group. 

Another commenter stated that 

another facility, which has an average 

mercury reduction efficiency level of 

99.995 percent, represents the ‘‘best 

controlled’’ similar source for the carbon 

process group and should be the basis 

for the alternative limits for new carbon 

processes. 

Several commenters requested 

clarification of the way in which 

compliance with the alternative for 

percent reduction would be 

demonstrated for new sources when 

there are multiple control devices on an 

emission unit. 

Response: We eliminated in the final 

rule the compliance alternative of 97 

percent reduction for new carbon 

processes. After reviewing the 

comments received on this standard and 

giving further consideration to the 

practicality of how it would be 

measured, we concluded that this 

option would be difficult to implement, 

particularly when multiple processes 

that are operated at different times vent 

to a single control device and stack. In 

addition, we have limited data 

supporting this compliance alternative. 

In proposing this alternative for 

comment, we had hoped to, but did not 

receive additional data indicating that 

the 97 percent reduction option would 

be equivalent in stringency to the 

proposed new source limit of 0.14 

pounds of mercury per ton of 

concentrate. Largely due to the reasons 

stated above, we have eliminated the 97 

percent control efficiency option for 

new carbon processes in the final rule. 

In addition we are not allowing this 

percent reduction to be used for existing 

carbon sources. We also note that the 

facility that one commenter identified as 

having an average mercury reduction 

efficiency level of 99.995 percent is now 

being used as the ‘‘best controlled’’ 

similar source for the final MACT 

standard for new carbon processes with 

mercury retorts. 


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D. Compliance Determinations 

1. Timing for Compliance 

Determinations 

Comment: Several commenters 

requested that the compliance deadline 

for existing sources be 3 years after the 

effective date of the rule, rather than the 

2 years proposed. The commenters 

noted that several facilities will have to 

install control devices to achieve the 

MACT floor limits that have been 

proposed. The commenters explained 

that the controls must be custom 

designed for the unique characteristics 

of each process and associated process 

streams at each facility and stated that 

it can be time consuming and difficult 

to design, procure, construct, and 

implement emission controls to ensure 

effective operation for the particular 

source. 

Response: After reviewing the 

information provided in public 

comments on the challenges of 

retrofitting new controls, we believe that 

allowing 3 years for existing sources to 

comply is appropriate. Given the 

complexity of the sources, the 

combinations of control devices that are 

needed in many cases, and the amount 

of time necessary for designing, 

installing, testing, and commissioning 

additional emission controls for 

mercury, we conclude that 2 years may 

not provide adequate time for existing 

sources to comply with the final 

emission standards. 

Comment: Several commenters 

recommended that the rule specify that 

source testing results be used to 

determine compliance for the calendar 

year in which the test was conducted 

rather than to determine compliance for 

the prior 12 months. The commenters 

suggested that the source test results be 

applied to the hours of operation at the 

end of the calendar year to determine 

the source’s compliance with the MACT 

standard on an annual basis, as required 

in the NMCP. The commenters 

suggested that, if more than one source 

test is conducted in a year, the facility 

should average the mercury emission 

test results to determine compliance for 

the calendar year in which the tests 

were conducted. 

Another commenter commented that 

the annual compliance testing should 

not be constrained to the same calendar 

quarter each year. The commenter stated 

that this can lead to testing during 

periods of operation that may not 

represent normal production capacities. 

The commenter believes that mercury 

emissions testing should be scheduled 

for the most appropriate time interval 

throughout the calendar year. 

Response: The permitting authority 

needs to be able to determine 

compliance with the NESHAP as soon 

as possible after the tests are completed 

and test results are available. 

Consequently, the final rule requires 

that initial compliance be determined 

based on production data and operating 

hours for all full calendar months 

between the date the rule is published 

in the Federal Register and the date of 

the compliance test, and subsequently, 

annual compliance must be based on 

production data and operating hours for 

the 12 full calendar months preceding 

the compliance test. This allows the 

permitting authority to determine if the 

affected source is in compliance in a 

timely manner. (This is consistent with 

the way compliance determinations are 

made in another MACT rule that uses a 

similar format—National Emission 

Standards for Hazardous Air Pollutants 

for Primary Lead Smelting, 40 CFR part 

63, subpart TTT.) If compliance was 

based on a calendar year, as suggested 

by the commenter, then we would not 

know if a source is in compliance until 

after December each year. For example, 

if a source conducted its compliance 

test in March, we would have to wait 

about 9 more months before we could 

determine if that source was actually in 

compliance. After those 9 months, if the 

source was not in compliance, it would 

mean that the source could have been 

out of compliance for the previous 9 

months. 

Moreover, we do not believe that 

compliance with the NESHAP based on 

the production data from the 12 months 

prior to the compliance test would 

cause problems with reporting under 

the State program. It is our 

understanding that the emissions limits 

in the Nevada State Phase 2 permits are 

(or will be) based on concentration in 

the stacks (e.g., micrograms per cubic 

meter (μg/m3)). The limits in this final 

rule are based either on pounds of 

mercury per million tons of ore or 

pounds of mercury per tons of 

concentrate. Therefore, the companies 

can continue to report the annual 

emissions as required under the TRI 

program and the State program without 

conflict with this rule. 

If multiple compliance tests are 

conducted during the year, then a 

compliance determination must be 

made for each separate compliance test 

based on the production data and hours 

of operation for the 12 full calendar 

months preceding each test (i.e., the 

results of multiple compliance tests 

conducted throughout the year are not 

averaged to provide a single compliance 

determination for the year). 

We understand that the rule, as 

proposed, may have required all 

existing sources to conduct their 

subsequent annual compliance tests in 

the same calendar quarter, and this may 

pose a scheduling problem because of 

the large number of facilities located in 

the same State (e.g., Nevada). Our 

concern was that subsequent annual 

compliance tests, if not separated in 

time, could be conducted for two 

different years with little time between 

the two tests (e.g., only a few days apart 

for the extreme case where the first test 

is conducted in late December and the 

second one in early January of the 

following year). We are providing 

scheduling flexibility by requiring that 

annual compliance tests be at least 3 

months apart and no more than 15 

months apart, and we are providing a 

similar separation for the period 

between the initial compliance test and 

the first annual compliance test. We do 

not believe that tracking multiple 

compliance dates is a particular 

problem for the permitting authority 

because that is the case for many other 

source categories subject to annual 

compliance testing. 

2. Test Methods 

Comment: Several commenters 

supported EPA’s proposal of alternate 

Methods 30A and 30B for demonstrating 

compliance. One commenter supported 

EPA’s requirement to use Method 29 as 

an emission test method, but 

recommended two revisions: Requiring 

a determination of the absence of 

cyclonic flow before sampling, and a 

minimum sampling time of 90 minutes 

for each test run. The commenter also 

stated that they do not support the use 

of the Ontario Hydro Method (ASTM 

D6784–02), Method 30A, or Method 30B 

as mercury test methods. The 

commenter believes that the methods of 

demonstrating compliance with the 

emissions standards should be 

consistent with the methods utilized to 

establish the emission standards, which 

were based mainly on Method 29 data. 

The commenter said that the typical gas 

streams associated with the gold mining 

industry have high particulate loadings, 

high mercury concentrations, sulfur 

dioxide (SO2), and contain particulatebound mercury. The commenter also 

stated that the alternative methods were 

not developed specifically for the gold 

mining industry and their typical gas 

streams and concluded that the results 

from the various alternative methods 

will yield varying results, will not be 

comparable, and will provide 

inconsistent reporting of overall 

mercury emissions. 


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Response: Method 29 references 

Method 1, which requires cyclonic flow 

checks under certain circumstances. 

Consequently, in the final rule, we have 

removed the specific requirements for 

cyclonic flow checks prior to every 

stack test that were in 

§ 63.11646(a)(1)(vi) of the proposed rule. 

Owners or operators should follow the 

requirements in the applicable EPA 

reference method and any additional 

requirements specified by the 

permitting authority. 

When specifying the minimum 

requirements for compliance tests, it is 

more important to specify a minimum 

sampling volume than a minimum 

sampling time because the detection of 

a regulated pollutant is a function of the 

volume of the sample rather than the 

length of time taken to collect the 

sample. Thus, the final rule does not 

specify a minimum sampling time. We 

are also changing the required minimum 

sampling volume to be 30 dscf rather 

than the 60 dscf as proposed in 

§ 63.11646(a)(2) because we believe that 

30 dscf generally will be adequate for 

detecting mercury emissions for this 

industry. Affected facilities should be 

aware, however, that the minimum 

sample volume may sometimes result in 

a failure to detect any mercury (a nondetect) emitted from a process unit 

subject to the emission standard (for the 

group of process units within the 

affected source) because of a mercury 

concentration at the outlet lower than 

expected. If the emission testing results 

for any of the emission points yield a 

non-detect value, then the minimum 

detection limit (MDL) must be used in 

calculating the emissions for that 

emission point and, in turn, for 

calculating the sum of the mass 

emissions for all emission points subject 

to the emission standard for 

determining compliance. If the resulting 

mercury emissions (in pounds of 

mercury per ton of concentrate, or 

pounds of mercury per million tons of 

ore) for the affected source are greater 

than the MACT emission standard, the 

owner or operator may use procedures 

that produce lower MDL results and 

repeat the mercury emissions testing 

one additional time for any emission 

point for which the measured result was 

below the MDL. If this additional testing 

is performed, the results from that 

testing must be used to determine 

compliance (i.e., there are no additional 

opportunities allowed to lower the 

MDL). 

After reviewing the information 

provided by the commenter about 

Method 29, we agree with the 

commenter that Method 29 is the most 

appropriate method for compliance 

determinations for this source category 

because of the unique characteristics of 

these sources. Therefore, we are 

promulgating Method 29 as the main 

method for compliance in this rule. 

Alternative methods, such as 30B and 

the Ontario Hydro method (OHM; 

ASTM D6784–02), could be used to 

demonstrate compliance for this source 

category if approved by the permitting 

authority. These alternative methods 

(such as 30B and OHM) may prove to 

be more appropriate under certain 

circumstances. However, we have 

omitted Method 30A as an option in the 

final rule, as it is not yet in general use. 

E. Monitoring 

1. Compliance Assurance 

Comment: One commenter noted that 

EPA’s proposed mercury standards are 

expressed in a format of pounds of 

mercury per million tons of ore 

processed and observed that the 

proposed rule requires stack testing only 

once a year. The commenter claims that 

EPA’s proposed monitoring 

requirements would not demonstrate 

whether sources are in compliance with 

their emission standards, which renders 

the rule unenforceable. According to the 

commenter, the once-a-year stack test 

would provide no indication as to what 

a mine’s emissions were the rest of the 

year. The commenter said that a source 

that failed its stack test would have only 

one violation of emission standards, 

even if that test showed that the source 

likely violated its emission standard 

throughout the year. The commenter 

believes that EPA’s proposed 

monitoring requirements would not 

assure compliance with the proposed 

emission standards. The commenter 

also noted that EPA proposed to require 

sources to monitor their mercury 

emissions either with CEMs, sampling, 

or various types of parametric 

monitoring; however, these methods do 

not provide direct information about the 

pounds of mercury emitted. 

Consequently, none of these monitoring 

methods could be used to demonstrate 

whether a source is in or out of 

compliance with the proposed emission 

standards. 

According to another commenter, all 

three affected source categories should 

be required to use CEMS at all times and 

at all emission points. The commenter 

stated that the ore pretreatment group 

especially needs CEMS because of 

variable levels of mercury in the ore and 

different operational measures within 

the control of the facility. 

Other commenters supported a 

requirement for continuous monitoring 

and said that the CEMS should be 

incorporated into the compliance 

regime as well. The commenters believe 

that, if the monitoring results indicate 

that the mine is consistently out of 

compliance for a period of one week 

without correction, the process unit 

should be subject to compliance-based 

penalties and/or shut down until 

corrections are made and the process 

unit is back in compliance. According to 

the commenters, quarterly stack testing 

should still be required to demonstrate 

that the CEMS is working. 

Response: We recognize the 

importance of requiring adequate 

monitoring to assure compliance with 

the emission standards. Because of the 

higher mercury emitting potential of the 

roaster, we proposed the option of 

mercury monitoring using CEMS or 

weekly monitoring with PS 12B with 

associated parametric monitoring as 

well. We are including in the final rule 

the option to perform continuous PS 

12B monitoring, and, as with the CEMS, 

associated parametric monitoring would 

not be required. We are changing the 

frequency of the proposed weekly 

concentration monitoring approach for 

roasters to twice per month (at least 11 

days apart) and would allow a facility 

to conduct a Method 30B test (as an 

alternative to a PS 12B test), 

supplemented with continuous 

parametric monitoring. We changed the 

frequency because we believe that 

sampling twice per month, coupled 

with continuous parametric monitoring, 

is sufficient for determining that the 

roaster control devices are operating 

properly. We added the alternative of 

using Method 30B because this method 

directly measures mercury 

concentration and is a valid means of 

determining whether the concentration 

is below the operating limit established 

during the initial performance test. The 

twice per month Method 30B 

measurements will provide a 

concentration value that can be 

compared to that operating limit to 

determine if an exceedance of the 

operating limit has occurred. Also, if the 

twice monthly sampling shows repeated 

deviations over time, EPA could decide 

at a later date that CEMS or continuous 

monitoring with PS 12B are appropriate 

and necessary for roasters. 

We disagree with the commenter that 

the proposed monitoring requirements 

render the rule unenforceable. Although 

the mercury concentrations monitoring 

for roasters along with the parametric 

monitoring of all control devices on all 

units do not directly measure pounds of 

mercury per ton of input, we believe 

that these actions, along with the annual 

emissions compliance tests, is still an 

acceptable approach to assure 


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compliance with the emission standards 

all year long. Parametric monitoring of 

control devices assures that the control 

devices are operating properly (and 

reducing emissions) on an ongoing 

basis. Any exceedance of the parameter 

limits or operating limits triggers 

corrective action. If corrective action 

does not return the mercury 

concentration within the established 

limits, the plant must conduct a full 

compliance test and determine if the 

source is meeting the mass-based 

(lb/million tons of ore) emission 

standard. 

We do not believe that we should 

include CEMS as a monitoring option 

for the non-roaster sources. These 

sources have less potential mercury 

emissions, and requiring CEMS on all 

these other units would be quite costly 

and burdensome. Moreover, most of 

these other units are, or will be, 

controlled with carbon adsorbers, and 

the carbon adsorber monitoring required 

by the final rule is an effective means of 

ensuring the controls are working 

effectively on a continuing basis. We 

consider that either frequent testing of 

carbon beds to monitor for breakthrough 

using Method 30B, or frequent 

adsorbent sampling for mercury content, 

is an effective way to ensure these 

mercury control systems are operating 

properly on a continuing basis. The 

final rule also requires parametric 

monitoring of wet scrubbers that are 

considered the final mercury control 

(i.e., not followed by a carbon adsorber 

or calomel mercury scrubber). We 

believe that annual tests coupled with 

appropriate parametric monitoring of 

the wet scrubbers are sufficient to 

ensure emissions are properly 

controlled on a continuing basis. 

With regard to the comment that 

quarterly stack testing should be 

required for facilities using a CEMS, we 

believe that following the Quality 

Assurance (QA) procedures detailed in 

40 CFR 60, Appendix F, are sufficient to 

ensure the CEMS continues to operate 

as designed, and in this case, additional 

stack sampling is not necessary. 

2. Operating Limits 

Comment: One commenter stated that 

the operating limits for roasters and for 

carbon adsorbers are inappropriate and 

set up a second set of MACT standards. 

The commenter claimed that the 

operating limits do not take into account 

the effects of: Hours of operation of a 

process unit on mercury emissions; 

reduction in performance of a process 

unit offset by an improvement in 

performance of another process unit; 

variability in the exhaust gas flow rates 

with no appreciable effect on the 

corresponding mercury emission rate; 

and variability in the inlet mercury 

concentrations to a carbon adsorber. 

These factors all result in variability in 

the outlet mercury concentration. The 

commenter also noted that the proposed 

operating limit for carbon adsorbers 

could result in premature carbon change 

out, resulting in the generation of more 

waste. The commenter recommended 

that EPA defer to the Nevada state 

monitoring requirements and only 

provide for monitoring of throughput 

and annual mercury emission testing to 

demonstrate compliance with the 

MACT emission standard. The 

commenter believes that any operating 

limit parameters must be established 

based on manufacturer specifications 

and recommendations in coordination 

with the permitting authority and not 

based on values measured during source 

compliance testing. 

Response: We proposed the mercury 

operating limits as a monitoring tool to 

ensure that the processes within 

individual affected sources and their 

associated control devices are 

functioning properly on a continuing 

basis and not as a second set of MACT 

standards. We developed emission 

standards for four affected sources, and 

the emission standard for an affected 

source applies to the sum of emissions 

from all process units within the 

affected source. One unit could have an 

upward fluctuation in mercury 

concentration, but the group of process 

units could still meet the MACT limit. 

We see the value of the operating limit 

approach as sufficient to detect 

significant increases in emissions and as 

a valuable tool to ensure the control 

devices are operating effectively and 

provide quick notification of a potential 

problem with controls or emissions. The 

monitoring parameters are used as 

compliance indicators, and the relevant 

mercury operating limits are the main 

‘‘triggers’’ of a possible emissions 

increase and are set to alert facility 

operators when emissions are greater 

than the corresponding mercury 

operating limit. We believe it is 

important to have such monitoring in 

the rule to ensure the control devices 

are working properly. 

Regarding specific comments about 

monitoring the carbon adsorber, the 

State of Nevada has had good results 

with conducting sampling of the carbon 

adsorber to maintain its performance. 

The final rule offers an additional 

option of measuring the mercury 

concentration exiting the carbon 

adsorber that also achieves the same 

objective of avoiding breakthrough of 

the bed. We do not expect sudden 

dramatic failures of this technology. 

Instead, we expect to obtain close 

control of performance by ensuring that 

the carbon is changed in a way that 

prevents breakthrough. This monitoring 

methodology should also prevent 

premature replacement of the bed. 

We disagree with the comments that 

only monitoring for throughput and 

annual emissions testing are sufficient 

to demonstrate compliance with the 

MACT standards. Such an approach 

does not yield sufficient data to assure 

compliance with the emission standards 

either directly or indirectly by assuring 

that the control devices are operating 

properly. The parametric monitoring 

and operating limits specified in this 

final rule provide assurance that control 

devices are properly operated and 

maintained between emissions tests, 

and exceedances of the operating limit 

require corrective action. With regard to 

the comment that any operating limit 

parameters should be based solely on 

manufacturer specifications and/or in 

consultation with the permitting 

authority, we have provided various 

options in this rule for establishing 

control device parameter limits. Control 

device operating parameter values 

sometimes are site-specific and are 

associated with a level of emissions 

from the source. Therefore, it is 

generally preferable for certain control 

device parameter limits to be associated 

with an emissions test that demonstrates 

compliance with the emissions 

standards. However, we agree that 

certain parameters for mercury 

scrubbers applied to roasters, such as 

the ranges associated with ensuring the 

proper chemistry of the scrubber, are 

best provided by the system’s 

manufacturer. Guarantees of 

performance are usually conditioned by 

requiring that the system be operated as 

designed and specified by the 

manufacturer, and there is no assurance 

that a potentially narrow range that 

would be established during a short 

performance test reflects the full 

applicable range of proper operation. 

We also realize that it may be preferable 

that the permit authority establish the 

parameter limits for some of the control 

devices in this industry because of some 

of the unique characteristics of the 

processes and control devices used in 

this industry and the experience of the 

permit authority with addressing these 

sources. Therefore, this final rule allows 

three options for establishing parameter 

limits: (1) Based on the initial 

compliance test; (2) according to the 

manufacturer’s specifications; or (3) 

based on limits established by the 

permitting authority. 

Comment: Some commenters stated 

that their established parametric 


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monitoring programs are sufficient to 

confirm that mercury emission controls 

are functioning properly for roasters. 

The commenters also stated that the 

NMCP permits have required parametric 

limits and that additional CEMS for 

mercury would neither improve the 

operation of these current controls, nor 

reduce mercury emissions. The 

commenters concluded that the 

operating parameters monitored on a 

regular basis are key parameters for 

measuring the efficiency and operation 

of the mercury controls and that 

operating each of these units within the 

optimum ranges ensures that mercury 

emissions are being effectively 

controlled. 

Response: As discussed above, we do 

not believe parametric monitoring alone 

is sufficient for roasters because of the 

very high mercury emission potential, 

unless the facility has adequately 

demonstrated that the mercury 

emissions from the roasters are 

consistently very low (e.g., less than 10 

pounds per million tons). We have 

concluded that the combined approach 

of annual stack compliance testing along 

with the mercury concentration 

monitoring and parametric monitoring 

requirements and options outlined in 

this rule are necessary to detect excess 

emissions and to ensure controls are 

working effectively on a continuous 

basis. We note that for facilities that 

choose to monitor the mercury 

concentration from the roaster with 

CEMS or continuous PS 12B sampling, 

they do not have to do parametric 

monitoring. For facilities that can 

demonstrate their mercury emissions 

are less than 10 lbs per million tons of 

ore, they only have to do parametric 

monitoring, no mercury concentration 

monitoring. 

3. Mercury Concentration Monitoring 

for Roasters 

Comment: One commenter stated that 

the proposed provisions for monitoring 

mercury concentrations in roaster 

emissions are not based on roaster 

process and pollution control device 

operational parameters and would not 

yield reliable information that can be 

used for detecting and correcting 

problems. The commenter also stated 

that the formula for establishing the 

mercury operation limit for roasters is 

not appropriate because it uses an 

emission limit that is based on emission 

test data from several process units in 

addition to the roaster. The commenter 

recommended using the methods 

proposed for parametric monitoring of 

roaster emission control devices for all 

roasters. The commenter also has 

concerns about utilizing PS 12A 

(mercury CEMS) and PS 12B for 

emissions monitoring purposes because 

there are terms and conditions listed in 

the proposed rule that are not fully 

defined. The commenter also 

recommended deleting the emissions 

monitoring requirements for mercury 

concentration for carbon adsorbers for 

the same reasons described above for 

roasters. 

Response: We disagree with the 

comment that monitoring the mercury 

concentration in roaster emissions 

would not yield reliable information 

that can be used for detecting and 

correcting problems. An elevated 

mercury concentration in the roaster 

stack gas indicates that there could be 

a problem with either the process or the 

control device, which could result in 

excess mercury emissions from that 

unit. Monitoring the mercury 

concentration in roaster emissions 

provides a direct measure of the 

regulated pollutant (mercury). The 

commenter is correct that the formula 

for establishing the mercury operating 

limit for roasters is based on emission 

tests performed on several processes 

units in addition to the roaster. 

However, for the facilities with roasters 

that will be subject to the requirements 

to monitor mercury concentration, the 

roaster is the biggest source of potential 

mercury emissions within the affected 

source. Therefore, we conclude that 

changes in the mercury concentration in 

the roaster exhaust gases provide a 

reasonable indication of overall 

emissions from the affected source. In 

addition, the operating limit is not used 

directly to determine compliance with 

the MACT emission standard. As 

mentioned above, it is designed to 

detect elevated mercury concentrations 

in the roaster stack gas, which could 

indicate a problem with either the 

process or the control device. We 

continue to believe that it is necessary 

and appropriate to monitor mercury 

concentration for the largest source of 

potential mercury emissions in the 

source category (i.e., the roaster) to 

detect excursions in emissions that must 

be addressed when the operating limit 

is exceeded. By developing the mercury 

operating limit from the emission 

standard and compliance test results, an 

exceedance of the mercury operating 

limit will indicate a potential increase 

in emissions and that corrective actions 

are needed. 

As described above, we believe that 

either continuous mercury sampling or 

mercury sampling twice per month 

(coupled with continuous parametric 

monitoring of the control device) should 

be required for the roaster emissions. If 

a CEMS is used, the daily average 

mercury concentration is calculated by 

averaging the hourly emissions 

concentrations during that day. The 

final rule includes continuous sampling 

with PS 12B as an option for monitoring 

roasters. If PS 12B is used for 

continuous integrated sampling (i.e., 

without parametric monitoring), the 

daily average concentration is 

determined by assigning the mercury 

concentration measured by the sorbent 

trap monitoring system (total mass of 

mercury collected during the sampling 

period divided by the sample volume) 

as the daily average value to each of the 

days covered by the integrated sample. 

A third option is based on short-term 

sampling twice per month (at least 11 

days apart) for mercury concentration 

using either PS 12B or Method 30B, and 

if this option is chosen, continuous 

parametric monitoring of the mercury 

scrubber must also be performed. For 

this short-term sampling option (twice 

per month sampling) each measured 

mercury concentration must be 

compared to the operating limit to 

determine if an exceedance has 

occurred. For the contents of the 

monitoring plan, see 40 FR 63.8(d)(3) 

and 40 CFR part 60, Appendix F. 

We also disagree that parametric 

monitoring alone is sufficient for carbon 

adsorbers. For carbon adsorbers, 

measuring the mercury concentration 

exiting the carbon bed is also a direct 

measure of the pollutant of interest. 

(The other option as established for 

years in NDEP operating permits 

involves sampling the carbon for 

mercury content.) An elevated mercury 

concentration indicates that there could 

be a problem with either the process or 

the control device, which could result 

in excess mercury emissions from that 

unit. We have established exit 

concentration monitoring requirements 

in many rules for emissions of organic 

compounds exiting carbon adsorbers. 

That monitoring has proven to be 

effective to prevent or detect 

breakthrough, and the same principles 

apply here for mercury. 

Comment: Commenters stated that 

CEMS for gold mining operations are 

not capable of accurately measuring 

mercury emissions and that there are 

three major challenges with the 

feasibility of mercury CEMS for the gold 

mining industry: Mercury CEMS 

calibration, sample transport, and 

system operability and reliability. The 

commenters are concerned with the 

unavailability of a means to calibrate the 

CEMS for roasters because existing 

calibrator designs are simply not 

capable of generating mercury 

concentrations high enough to provide 

meaningful upscale calibration points 


jlentini on DSKJ8SOYB1PROD with RULES2
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that correspond to gold mining source 

characteristics. The commenters noted 

the unavailability of National Institute 

of Standards and Technology (NIST) 

traceable calibration gases and stated 

that the current calibration standards 

traceable to NIST do not apply to the 

full range of mercury concentrations 

that can be present in the exhaust gases 

of roasters. The commenters concluded 

that the lack of a NIST-traceable 

standard is a fatal flaw that precludes 

using mercury CEMS to monitor roaster 

emissions. Regarding sample transport, 

the commenters said that current 

designs of mercury CEMS for coal-fired 

electric generating units require high 

temperature umbilical lines to transport 

the sample from the stack to the 

analyzer and that CEMS on coal-fired 

electric generating units have seen 

umbilical failures occur, representing 

another challenge to having CEMS 

function consistently for the continuous 

monitoring of mercury from industrial 

sources. The commenters were also 

concerned with the CEMS operability 

and reliability because mercury CEMS 

must contain some type of converter to 

reduce oxidized mercury to elemental 

mercury and premature catalytic 

failures periodically occur in these units 

resulting in several days of missing data. 

The commenters continued by stating 

that users reported mercury CEMS to be 

unavailable as much as 30 to 40 percent 

of the electric generating unit operating 

time. The commenters believe the 

amount of downtime to be expected 

from these systems on roasters would 

likely be even higher. The commenter 

concluded that the breakdown events, 

combined with the other types of 

failures, result in data availability that is 

substantially inferior to parametric 

monitoring and cannot justify the 

significant cost and resource investment 

necessary to install, operate, and 

maintain these devices. 

The commenters are concerned that 

continuous data reports of mercury 

emissions that are not accurate, reliable, 

or credible could be offered as ‘‘credible 

evidence’’ to assert a violation. The 

commenter concluded by stating that 

this concern was particularly troubling 

in Nevada, where there are separate 

mercury limits established pursuant to 

State law. 

Response: Regarding the feasibility of 

using CEMS to monitor mercury 

emissions from roasters, CEMS have 

been demonstrated for process units 

similar to roasters (e.g., coal-fired power 

plants), and we believe there is no 

technical reason why they will not work 

for the roasters. (See NESCAUM, 2010. 

Technologies for Control and 

Measurement of Mercury Emissions 

from Coal-Fired Power Plants in the 

United States: A 2010 Status Report 

Northeast States for Coordinated Air 

Use Management (NESCAUM) July 

2010). 

Many of the issues with mercury 

CEMS have been resolved as facilities 

have gained experience with their use. 

However, we realize that mercury 

concentrations in the exhaust gases from 

roasters can be higher than the range of 

concentrations for coal-fired power 

plants, and that the calibration 

standards traceable to NIST, that have 

been available in the past, have not 

applied to the full range of mercury 

concentrations that can be present in the 

exhaust gases from roasters. 

Nevertheless, as we discussed in the 

proposal preamble, CEMS 

manufacturers supply calibration 

standards for the ranges of 

concentrations seen at roasters. 

In addition, the NIST has recently 

completed certification of a ‘NIST 

Prime’ elemental mercury gas generator 

at concentrations of 41, 68, 85, 105, 140, 

185, 230, 287, and 353 μg/m3. Mercury 

gas generator vendors may now submit 

elemental mercury gas generators for 

certification to serve as ‘Vendor Primes’ 

in a wide range of concentrations. 

Therefore NIST traceable mercury gas 

standards can now be made available in 

concentrations that cover the full range 

of the concentrations typically 

measured from roasters. 

After consideration of public 

comments, we continue to believe 

CEMS are a valuable tool and a 

reasonable option for monitoring 

mercury concentrations and comparing 

those concentrations to the operating 

limit that is established by CEMS 

measurements made during the 

compliance test. However, we also point 

out that the final rule does not require 

the use of CEMS; instead, the final rule 

includes CEMS as one of the three 

monitoring options. The other two 

options that we are promulgating for 

monitoring mercury from roasters are: 

(1) Continuous monitoring using PS 

12B; and (2) twice per month sampling 

using PS 12B or Method 30B coupled 

with parametric monitoring. All three of 

these monitoring options are intended 

to ensure that emissions from the 

roasters are not exceeding operating 

limits, or if they do exceed the operating 

limits, that corrective actions are taken 

in a timely manner to bring the 

emissions down to within the operating 

limits. If these corrective actions are not 

successful then the facility must 

perform a complete compliance test 

using the methods in section 63.11646 

to determine whether the affected 

source is in compliance with the MACT 

standard. The CEMs can also be used to 

help identify problems with control 

systems and ensure that corrective 

actions are taken immediately to fix 

such problems. The exceedance of the 

operating limit is not intended to 

determine if the source in violation of 

the MACT standard. Rather, it would be 

the subsequent compliance test 

pursuant to section 63.11646 that would 

be used to determine if the source is in 

compliance with the MACT standard. 

We understand the commenter’s 

concerns regarding the transport of 

samples and converter failures. 

However, we have revised the final rule 

to give facilities 3 years to comply with 

the rule which will allow extra time to 

successfully set-up and operate controls 

and monitoring equipment to be able to 

comply with the MACT standards. We 

believe this will provide sufficient time, 

for facilities that choose the CEMs 

monitoring option, to identify and 

resolve issues with the transport of 

samples and converters. 

Comment: One commenter stated that 

the regulated industry has no 

experience with direct measurements of 

mercury concentrations at the roaster 

exhaust gas stream. As a result, the 

commenter believes that there will be 

problems in collecting data, establishing 

appropriate timeframes for sampling 

under PS 12B, maintaining instrument 

reliability for CEMS, and in establishing 

confidence in the accuracy of the results 

reported by these methods. The 

commenter claimed that the calculated 

operating limit based on source testing 

and simultaneous direct measurements 

may not be reflective of the future daily 

operations of all the stack emissions. 

The commenter noted that flow rate 

measurements are critical in verifying 

compliance with actual emission limits 

because sometimes lower flow rates of 

the stack exhaust gas flow can 

artificially elevate the mercury 

concentration in the gas stream with no 

real effect on emissions. The commenter 

concluded that any exceedance in 

mercury concentration should be 

verified first with a compliance test 

before halting the roaster production. 

Response: We have learned from the 

comments received that there may be a 

learning curve for facilities to 

implement the concentration 

monitoring procedures. As described in 

section V.D. of this preamble, we have 

established in the final rule a 

compliance date that is 3 years after the 

effective date of the final rule for 

existing sources, partly to allow sources 

time to ensure they can successfully 

comply with the monitoring 

requirements, but mainly to allow time 

to install new mercury emission 


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controls that we believe will be 

necessary to meet the emission 

standards in the final rule. 

We agree that mercury concentration 

measurements are not direct 

measurements of the emissions rate 

from the affected source and that flow 

rate, production, and other factors need 

to be considered. These are some of the 

reasons that the operating limit is not 

being used as a direct measure of 

compliance with the MACT standards. 

However, concentration measurements 

above the operating limit should 

indicate that either controls are not 

working effectively or other problems 

are occurring. In either case, 

exceedances of the operating limit 

require investigation and may require 

corrective actions. The requirement to 

shut down the roaster has been removed 

from this final rule. However an 

exceedance of the mercury 

concentration does trigger corrective 

action, and if not corrected requires a 

compliance test. 

Comment: One commenter requested 

that EPA reduce the weekly Method 12B 

monitoring frequency to quarterly or at 

most monthly. The commenter also 

requested that EPA include a provision 

that allows for a source to demonstrate 

a correlation or consistency of 

performance such that the Method 12B 

sampling frequency can be further 

reduced based on the permitting 

authority’s acceptance of the 

demonstration. The commenter 

suggested that if multiple Method 12B 

samples are collected in a single day or 

over multiple days in the calendar 

week, then the samples should be 

averaged, and this average concentration 

should be compared to the operating 

limit. The commenter said that, for 

stacks with high mercury concentration, 

the sample collection time may be only 

an hour or two, and in this case, it may 

be important to collect more than one 

sample in a single day or over multiple 

days to obtain a representative mercury 

concentration measurement. 

Response: After taking into 

consideration the commenter’s 

rationale, under this monitoring option, 

the final rule requires the sampling of 

mercury concentration at least twice per 

month (with 2 samples taken at least 11 

days apart) instead of weekly sampling 

as proposed. If multiple samples are 

taken during the twice per month 

period, each result must be compared to 

the operating limit separately (i.e., not 

averaged). Otherwise, a high result from 

a sample taken near the end of the 

sampling period might not trigger 

corrective actions to correct a problem 

that developed at that time if the results 

are averaged with previous samples 

during periods of good performance. We 

do not agree with the suggestion to 

allow the monitoring frequency to be 

reduced if the monitoring results 

demonstrate consistency over the long 

term. We believe that monitoring the 

mercury concentration at least twice per 

month is necessary for roasters to ensure 

that potential problems with control 

systems are identified quickly and 

corrective actions are taken in a timely 

manner. 

4. Parametric Monitoring of Control 

Device for Roasters 

Comment: Some commenters 

recommended that EPA remove the 

provisions requiring monitoring of the 

mercury scrubber liquor flow rate and 

scrubber pressure drop because each 

facility that has a roaster has a unique 

sequence of air pollution control 

devices, and monitoring parameters that 

may be appropriate for one roaster may 

not be applicable to another. One of the 

commenters said that the scrubber 

liquor flow rate is not currently 

monitored, nor is it considered a critical 

parameter in the daily operation of the 

scrubber mercury removal tower 

associated with roasters at their facility. 

The commenter further explained that 

the scrubber is not a spray tower, but 

instead the liquor is recirculated in the 

tower, so the pump is monitored to 

insure it is operational. The commenter 

stated that the pressure drop across the 

mercury removal tower at its roasters is 

monitored, but is not considered a 

critical parameter and that the mercuric 

ion and chloride ion concentrations that 

they monitor are the critical parameters 

that define the effectiveness of the 

mercury scrubber. 

Another commenter added that, for 

the calomel-based mercury scrubbers, 

the key parameter is the reagent 

concentration in the solution exiting the 

scrubber and that maintaining the exit 

reagent concentration ensures there is 

sufficient reagent to react with the 

mercury vapor. The commenter noted 

that low exit concentrations indicate 

that either the liquor flow rate is too 

low, or the fresh reagent addition rate is 

too low. Thus, liquor flow rate does not 

need to be monitored in addition to 

reagent exit concentration. The 

commenter stated that if EPA continues 

to require them, the ranges should be 

based on the manufacturer’s 

specification or an alternative value 

approved by the permitting authority, as 

opposed to the three test runs from the 

initial compliance test. One commenter 

recommended that the corresponding 

range or limit for parametric deviations 

be applied to a daily average value 

rather than continuous instantaneous 

values or single samples. 

Another commenter also stated that 

the requirement to establish the 

minimum water flow rate and pressure 

drop of the wet scrubber on readings 

taken during the performance test 

should not apply to scrubbers on 

roasters. The commenter noted that 

these parameters were intended to 

monitor for physical processes, and the 

scrubbers on roasters often include 

chemical reactions, which are not 

monitored. 

Response: We agree that pressure 

drop is not relevant to mercury 

scrubbers because, unlike venturi 

scrubbers applied to control PM 

emissions, it is not related to its 

mercury emission control performance. 

We have removed pressure drop 

monitoring from the final rule for 

mercury scrubbers. However, we 

continue to believe that it is important 

to monitor the scrubber flow rate to 

ensure the scrubber solution is being 

delivered to the system and that the 

flow is adequate, which is related to the 

system’s performance. We understand 

that some facilities monitor mercury 

scrubber solution line pressure (solution 

header pressure) as an indicator of flow 

rate, and we agree this is adequate to 

ensure proper flow. Consequently, the 

final rule requires hourly monitoring of 

scrubber flow rate (or line pressure) for 

mercury scrubbers on roasters. As with 

the inlet temperature operating range, 

the minimum flow rate or line pressure 

must be established by one of the 

following three ways: (1) During the 

initial compliance test, (2) from the 

manufacturer’s specifications, or (3) 

based on the limits established by the 

permitting authority. If the facility 

chooses the option to establish the 

limits during initial compliance, the 

final rule requires the scrubber flow rate 

operating limit to be based on either the 

lowest value for any run of the initial 

compliance test or 10 percent less than 

the average value measured during the 

compliance test and the inlet gas 

temperature operating limit to be based 

on either the highest value for any run 

of the initial compliance test or 10 

percent higher than the average value 

measured during the compliance test. 

The final rule requires hourly 

monitoring and that corrective action is 

triggered if the flow rate or line pressure 

falls below the established parameter 

limit. 

Regarding the acceptability of 

scrubber flow rate and inlet gas 

temperature parameter values that were 

approved by permitting authorities prior 

to this final rule, such values must be 

established as specified in the final rule 


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and are not presumed in advance to be 

acceptable. Note that the monitoring 

requirements for wet scrubbers in 

§ 63.11647 of the final rule would not 

apply to the mercury scrubbers on 

roasters, or any wet scrubber prior to the 

mercury scrubber on the roasters. 

Comment: One commenter believes 

that establishing a maximum operating 

temperature for inlet gas concentrations 

by artificially increasing this 

temperature during compliance testing 

may destroy the control equipment, 

conflict with recommended operating 

temperatures, and artificially increase 

the reported mercury emissions. The 

commenter concluded that these 

parameters are not deemed critical in 

the effective operation of a mercury 

calomel scrubber. Another commenter 

added that their Compliance Assurance 

Monitoring (CAM) plan provides for an 

inlet gas temperature range of 32° to 

134 °F to prevent water freezing 

problems or extremely hot gas 

temperatures that could damage the 

mercury scrubber. The commenter 

stated that mercury scrubbers remove 

mercury from the gas stream through a 

chemical reaction and not a 

condensation mechanism and that lower 

temperatures will not remove (via 

condensation) additional mercury. The 

commenter explained that, although 

mercury scrubber inlet gas temperature 

is not a relevant control performance 

parameter, their facility maintains the 

inlet gas temperature below 134 °F and 

monitors the temperature daily to 

prevent damage to the controls system 

from excessively low or high gas 

temperatures. 

Response: After additional review of 

operating permits and consideration of 

public comments, we have found that 

the inlet temperature of the mercury 

scrubber is monitored and maintained 

within a range to provide operational 

flexibility with the lower end bounded 

to prevent freezing and the upper end 

bounded to prevent damage to 

equipment, which in turn could lead to 

excess emissions. In addition, we have 

learned that this temperature is 

dependent on the cooling tower water 

temperature used in the process, and 

this water temperature can vary quite 

widely from winter to summer. 

Facilities may not be able to address the 

issues described above if they can only 

use initial compliance testing to 

establish the inlet temperature operating 

range, as we proposed. Consequently, 

the final rule provides the following 

three ways for a facility with a roaster 

to establish an operating range for inlet 

temperature: (1) Based on the maximum 

inlet temperature during the initial 

compliance test; (2) from the 

manufacturer’s specifications; or 

(3) based on the limits established by 

the permitting authority. If the facility 

chooses the option to establish the 

limits during initial compliance, the 

final rule requires the inlet gas 

temperature operating limit to be based 

on either the highest value for any run 

of the initial compliance test or 10 

percent higher than the average value 

measured during the compliance test. 

The facility must monitor the 

temperature hourly, and any exceedance 

of the upper limit for temperature 

would trigger corrective action. 

5. Exceeding the Operating Limits for 

Roasters 

Comment: One commenter was 

concerned about the consequences of 

exceeding a parametric monitoring 

limit. The commenter remarked that 

shutting down the roaster for exceeding 

a monitoring parameter without 

evidence of an ongoing emission limit 

exceedance is arbitrary and capricious, 

unnecessarily punitive, and threatens 

the economic viability of the regulated 

sources. The commenter pointed out 

that the ranges of parameters measured 

during source testing are not necessarily 

the only ranges within which the unit 

can operate effectively. The parameters 

proposed by EPA are not the best 

parameters for monitoring roaster 

emissions and do not directly correlate 

to mercury emissions or proper control 

system operation. The commenter also 

objected to the period of only 45 

minutes to investigate and take 

corrective action. 

One commenter recommended that 

the corrective action response time be 

extended minimally to 48 hours after 

daily average values are processed, plus 

an additional 24 hours to verify the 

daily average parametric value was 

within limits. For facilities that conduct 

PS 12B sampling and a daily average 

parametric deviation persists for 96 

hours, the commenter recommended 

requiring sampling of the roaster’s 

exhaust using PS 12B within the next 24 

hours, then evaluating the mercury 

concentration results. If the mercury 

concentration is below the operating 

limit, then, within 10 days of receiving 

the analytical results, the facility should 

be required to either petition the 

permitting authority for a change in the 

parametric limits, or provide the 

permitting authority with a compliance 

plan that details corrective actions taken 

to date and the plan and schedule for 

bringing the parameter back within 

range. The commenter said that, if the 

mercury concentration is above the 

operating limit, the facility will be 

required to schedule an independent 

source testing firm to perform a 

compliance test within 45 days using 

one of the approved methods described 

in the rule. The commenter noted that 

the Nevada State agency requires 30 

days to review the testing protocol, and 

source testing companies typically 

require 30 days or more advanced 

notice. 

For roasters where direct 

concentration measurements are not 

required and a daily average parametric 

deviation persists for 96 hours, the 

commenter recommended that within 

48 hours, the facility should: (1) Provide 

the permitting authority with a 

compliance plan that details corrective 

actions taken to date and the plan and 

schedule for bringing the parameter 

back within the limits; or (2) schedule 

an independent source testing firm to 

perform a compliance test within 45 

days using one of the approved methods 

described in the rule. The commenter 

concluded that, if the test results show 

that the source has exceeded the 

threshold of 10 lb/million tons of ore, 

the facility would be required to 

implement direct mercury concentration 

measurements. 

One commenter requested that EPA 

provide an exception from the 

shutdown requirement when it can be 

demonstrated that, notwithstanding an 

exceedance of the parametric operating 

range, the roaster mercury emissions are 

less than the operating limit for mercury 

concentration. The commenter stated 

that the mercury concentration 

measurement is a more direct indication 

of the ultimate mercury emissions that 

the parametric monitors are designed to 

address. 

Response: We have investigated in 

greater detail the issues associated with 

monitoring roasters, and we have 

consulted with NDEP and the owners 

and operators of roasters to learn more 

about appropriate roaster monitoring. 

We understand that sometimes the 

ranges of parameters measured during 

source testing are not necessarily the 

only ranges within which the unit can 

operate effectively, that is why in the 

final rule we are offering two other 

options for establishing the ranges: 

(1) Based on manufacturer’s 

specifications; and (2) ranges approved 

by the permitting authority. We believe 

that monitoring the scrubber flow rate, 

inlet gas temperature, and scrubber 

liquid chemistry, as required in the final 

rule, are appropriate parameters to 

monitor. We have also revised the 

requirements of this final rule to 

provide assurance that timely corrective 

actions are taken when a monitoring 

parameter is exceeded, and we have 

included requirements for testing for 


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mercury concentrations to determine if 

the corrective actions were successful or 

if a deviation has occurred. The final 

rule includes parametric monitoring of 

the mercury scrubbers applied to 

roasters to control mercury. If a 

parameter is outside of the established 

range or limit, corrective actions are 

triggered. If corrective actions do not 

result in the parameter reading being 

corrected and verified within 48 hours, 

a mercury concentration measurement 

(using CEMs, Method 30B, 29, OHM, or 

PS 12B) must be made to determine if 

the operating limit for mercury 

concentration is being exceeded. The 

measurement must be performed and 

the concentration determined within 48 

hours (after the initial 48 hours, or a 

total of 96 hours). If the measured 

mercury concentration meets the 

operating limit for mercury 

concentration, the corrective actions are 

deemed successful. In addition, the 

owner or operator may request approval 

from the permitting authority to change 

the parameter range or limit based on 

measurements of the parameter at the 

time the mercury concentration 

measurement was made. If, on the other 

hand, the operating limit is exceeded, 

the exceedance must be reported as a 

deviation and the facility must conduct 

a full compliance test within 40 days to 

determine if the source is in compliance 

with the MACT limit. See § 63.11647(d) 

of final rule. 

Comment: For facilities that monitor 

roasters with a CEMS, one commenter 

proposed that corrective action be 

required within 48 hours of receiving 

and processing the results from the 

CEMS data, plus an additional 24 hours 

should be allowed to collect verification 

data to see if the daily average 

concentration was restored below the 

operating limit. The commenter 

recommended that, if the exceedance 

persists, the facility should be required 

to schedule an independent source 

testing firm to perform a compliance test 

within 45 days. 

For facilities that choose PS 12B 

monitoring, the commenter 

recommended that a deviation be 

considered an exceedance of the 

operating limit if the average of three 

consecutive sampling results (three 

weeks) were above the established limit. 

The commenter proposed that the 

facility should then have one week to 

take corrective actions, an additional 

week to take the verification sample 

using PS 12B, with receipt of results the 

following week (three weeks total). The 

commenter stated that if the exceedance 

persists, the facility should be required 

to schedule an independent source 

testing firm to perform a compliance test 

within 45 days using one of the 

approved methods described in the 

proposed rule. 

Response: After considering these 

comments on the mercury concentration 

operating limit and the above discussion 

on parametric monitoring of roasters, we 

have made several clarifications in the 

final rule. If a mercury concentration 

operating limit is exceeded from either 

daily average measurements from a 

CEMS, continuous sampling using PS 

12B, or from sampling twice per month 

(at least 11 days apart) using PS 12B or 

Method 30B, the exceedance must be 

reported to the permit authority as a 

deviation and corrective actions must be 

implemented within 48 hours upon 

receipt of the sampling results that show 

the deviation. Moreover, within 96 

hours of the exceedance, the owner or 

operator must measure the 

concentration again (with the CEMS, PS 

12B, Method 30B, Method 29, or OHM) 

and demonstrate to the permit authority 

that the operating limit for mercury 

concentration has been met, or inform 

the permit authority that the limit 

continues to be exceeded. If the 

operating limit is still exceeded after 

these 96 hours, the owner or operator 

must conduct a full compliance test for 

the ore pretreatment affected source 

within 40 days to determine if the 

affected source is in compliance with 

the MACT emission standard. If the 

source is determined to be in 

compliance, the compliance test may 

also be used to establish a new 

operating limit for mercury 

concentration. See § 63.11647(a)(1)(ii), 

(a)(2)(ii), and (a)(3)(ii) of the final rule. 

Comment: One commenter requested 

that EPA provide an exception to the 

shutdown requirement for facilities that 

have well-controlled roasters and elect 

to monitor under the proposed Option 

3. The commenter believes a facility 

should have time (45 days) to 

demonstrate that the roaster’s mercury 

emissions remain less than 10 lbs of 

mercury per million tons of ore. The 

commenter stated that this would be 

achieved by scheduling an independent 

source testing firm to perform a 

compliance test using methods 

described in the rule, and calculations 

that demonstrate compliance with the 

limit of 10 lbs per million tons of ore. 

Response: As we have discussed 

above, the final rule relies in part on 

parametric monitoring of mercury 

scrubbers used on roasters to assure 

compliance with the applicable 

emission standards, and when the 

measured parametric values are out of 

the established operating range, 

corrective actions must be taken. This is 

no different for facilities that qualify for 

the exemption described in 

§ 63.11647(a)(5) of the final rule (i.e., 

facilities exempt from mercury 

concentration monitoring by having 

demonstrated that their roaster 

emissions are less than 10 lb/million 

tons of ore). For these facilities, the final 

rule similarly requires that corrective 

actions be taken to restore the scrubber 

operating parameters to the established 

operating range. If the parameters are 

not restored to the established range 

within 48 hours of triggering the 

corrective actions, the owner or operator 

must perform mercury concentration 

sampling of the roaster emissions using 

PS 12B, Method 30B, Method 29, CEMS 

or OHM and determine the mercury 

concentration within 48 hours following 

the initial 48 hours (or a total of 96 

hours from the time the parameter range 

was exceeded). The measured 

concentration must be compared to a 

mercury concentration operating limit 

that is based on Equation 2 in the final 

rule, where the value for ‘‘Ctrap’’ in 

Equation 2 is based on the mercury 

concentration for the roaster measured 

during the most recent compliance test. 

If the measured mercury concentration 

meets the operating limit for mercury 

concentration, the corrective actions are 

deemed successful. In addition, the 

owner or operator may request approval 

from the permitting authority to change 

the parameter range or limit based on 

measurements of the parameter at the 

time the mercury concentration 

measurement was made. If the operating 

limit is exceeded, the facility must take 

corrective actions and report it to the 

permit authority as a deviation. The 

owner or operator must also conduct a 

compliance test within 40 days to 

determine if the roaster operations are 

in compliance with the emission 

standard. See § 63.11647(d) of the final 

rule. We also note that the requirement 

to shut down the roaster has been 

removed from this final rule. 

6. Carbon Adsorber Temperature 

Monitoring 

Comment: Several commenters stated 

their concern with the proposed 

requirement of monitoring gas stream 

temperature at the inlet to the carbon 

adsorber and maintaining the inlet 

temperature below the maximum 

temperature established during the 

compliance test. They noted that the 

primary purpose for monitoring the 

inlet gas stream temperature of carbon 

adsorbers is to prevent spontaneous 

combustion of the sulfidized carbon in 

the adsorber, not to detect excursions in 

mercury emissions. The commenters 

also stated that some carbon adsorption 

systems heat the gas stream prior to the 


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carbon adsorber to prevent moisture 

buildup and/or subsequent 

condensation in the carbon. The 

commenters explained that the NMCP 

already requires that the exit gas 

temperature of condensers prior to the 

carbon adsorbers be established to 

minimize mercury emissions from the 

condenser. The commenters believe that 

an increase in inlet gas temperature to 

a carbon adsorption unit is not 

indicative of an increase in inlet gas 

stream mercury emissions because the 

high operating temperatures of the 

processes volatilize approximately 100 

percent of mercury. The commenters 

stated that establishing a maximum 

operating temperature for inlet gas 

concentrations by artificially increasing 

this temperature during compliance 

testing may destroy mercury control 

equipment; conflict with NMCP 

requirements and/or manufacturer’s 

recommended operating temperatures; 

artificially increase the reported 

mercury emissions; or artificially 

decrease the allowable operating limit 

for mercury concentration. 

The commenters continued by stating 

that, if EPA persisted in requiring the 

monitoring of the gas stream inlet 

temperature, the maximum inlet 

temperature limit should be established 

by either the manufacturer’s 

recommendation and/or concurrence 

with the permitting authority. The 

commenters proposed monitoring the 

inlet temperature once per shift as an 

option to continuously monitoring the 

inlet temperature and comparing the 

daily averages rather than the hourly 

averages to the operating limit. The 

commenters noted that many facilities 

do not have digital acquisition systems 

capable of recording continuous data, 

and monitoring once per shift is 

sufficient to maintain control 

performance. The commenters 

suggested that, if corrective action is 

needed, the facility should be allowed 

to sample the carbon loading to 

demonstrate that the effectiveness of the 

carbon adsorber has not been adversely 

impacted. 

Response: The purpose of monitoring 

the inlet temperature to carbon 

adsorbers is not to provide an indication 

of higher mercury concentrations in the 

inlet stream as suggested by the 

commenters. The purpose is related to 

the fact that temperature is a 

fundamental parameter that affects the 

efficiency and capacity of carbon 

adsorbers. Generally, higher 

temperatures result in lower capacity 

and earlier breakthrough and, in fact, 

high temperatures are used to desorb 

adsorbed pollutants to regenerate 

carbon. In the extreme of temperature, 

the carbon adsorber might actually be 

desorbing rather than acting as a control 

device. This is particularly important 

for those carbon adsorbers applied to 

high temperature thermal processes, 

such as carbon kilns and melt furnaces, 

where it is possible for the exhaust 

temperature to rise above the normal 

operating temperature or above the 

temperature at which the carbon 

adsorber was designed to operate. For 

high temperature processes (such as 

furnaces), and not those such as 

electrowinning where the temperature 

may be near ambient conditions, we 

continue to require monitoring the inlet 

temperature. Owners or operators must 

establish an operating limit for 

temperature based on one of the 

following: (1) The maximum 

temperature during the initial 

compliance test; (2) from the 

manufacturer’s specifications; or 

(3) based on limits established by the 

permitting authority. If this established 

operating limit is exceeded corrective 

action must be taken and the 

exceedance reported as a deviation to 

the permit authority. Further, the final 

rule requires facilities to monitor inlet 

temperature once per shift rather than 

continuously, as was proposed. Because 

inlet temperatures should not vary 

greatly over the course of an 8- to 12- 

hour period, we believe monitoring 

once per shift is adequate. We also 

conclude that if a temperature 

exceedance has occurred, the carbon 

bed should be sampled or the outlet 

concentration determined, depending 

on the monitoring option chosen, within 

48 hours to ensure no permanent 

damage to the carbon adsorber occurred 

as a result of the deviation. We believe 

the temperature exceedance should be 

reported as a deviation even if the 

subsequent monitoring shows that the 

carbon bed is operating properly 

because the subsequent monitoring 

would not necessarily detect if mercury 

had been desorbed and excess emissions 

occurred. 

7. Monitoring of Wet Scrubbers 

Comment: One commenter proposed 

that only the scrubber water flow rate 

monitoring be required for wet 

scrubbers on the quenching circuits 

associated with the roaster. The 

commenter wanted to confirm that wet 

scrubber monitoring does not apply to 

wet scrubbers or condensers on roasters. 

Another commenter asked that EPA 

confirm that the term ‘‘wet scrubbers’’ 

does not include condensers, which are 

used throughout the mining processes 

for gas cooling to condense water or (in 

the case of retorts) mercury. Another 

commenter asked EPA to confirm that 

wet scrubber monitoring does not apply 

to wet scrubbers associated with ore 

preheaters. 

One commenter noted that 

continuous readings on wet scrubbers 

are unreliable and proposed monitoring 

the water flow rate and pressure drop 

once per shift. The commenter noted 

that if any water flow rate or pressure 

drop reading exceeds the operating 

limit, the facility should follow the 

procedures for operating limit 

exceedances. The commenter stated that 

many facilities do not have data 

acquisition systems capable of recording 

continuous data and that wet scrubbers 

are primarily used to control 

particulates. The commenter concluded 

by stating that wet scrubbers are not key 

mercury controls and monitoring once 

per shift is sufficient to maintain control 

performance on a continuing basis. 

One commenter wanted to confirm 

that the limits established during testing 

would not be more stringent than the 

requirements set forth in the Standards 

of Performance for New Stationary 

Sources for Metallic Mineral Processing 

Plants, which allows for plus or minus 

30 percent. Another commenter 

recommended that the operating limit 

for wet scrubber monitoring be based on 

either the lowest average value during 

any test run or no lower than 10 percent 

below the average value measured 

during the test. 

Response: We are clarifying in the 

final rule that § 63.11647(h) applies only 

to wet scrubbers not followed by a 

mercury control system (i.e., carbon 

adsorber, calomel mercury scrubber, 

etc.). It is necessary to monitor the 

primary mercury emission control 

device, which is the last stage of the 

exhaust gas cleaning treatment train, to 

ensure it is operating properly and 

controlling mercury emissions, and the 

rule does not require that wet scrubbers 

in the gas treatment train (typically used 

for control of PM and/or SO2) prior to 

the primary mercury emission control 

device be monitored under this rule for 

mercury emissions. However, if there is 

no carbon adsorber or mercury scrubber, 

and the wet scrubber in question is the 

only control device for mercury 

emissions, the final rule requires that it 

be monitored once per shift per 

operating day (e.g., minimum of two 

times per day) for pressure drop and 

flow rate with operating limits that are 

either established during the initial 

compliance test, from the 

manufacturer’s specifications, or based 

on approval from the permitting 

authority (except for pressure drop for 

autoclaves as discussed above). This 

applies to wet scrubbers on ore 

preheaters and quenching if there is no 


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9476 Federal Register / Vol. 76, No. 33 / Thursday, February 17, 2011 / Rules and Regulations 

carbon adsorber or mercury scrubber in 

the exhaust gas treatment train. As 

discussed above, the scrubber 

monitoring for roasters applies to the 

mercury scrubber (located at or near the 

end of the exhaust gas treatment train) 

and does not apply to the wet scrubbers 

that are used to remove PM and SO2

prior to the mercury scrubber. 

We are clarifying in the final rule that 

condensers, such as those found at 

roasters and mercury retorts, are not wet 

scrubbers. We agree that monitoring and 

recording the pressure drop once per 

shift is adequate for monitoring these 

wet scrubbers to ensure they are 

operating properly. We disagree that a 

buffer of ± 30 percent based on a certain 

New Source Performance Standard 

(NSPS) subpart is appropriate for this 

NESHAP for mercury. The comment 

suggesting an option of a ± 10 percent 

buffer around the average value during 

the performance test has merit as an 

option to only using the lowest value 

during any individual run as the 

operating limit. If the system is so stable 

that it shows very minimal variability 

during the performance test, we agree 

that it is appropriate to add ± 10 percent 

to account for potential future 

variability. Consequently, we are 

incorporating this option in the final 

rule, as suggested by the commenter. 

However, we are using ± 10 percent 

rather than ± 30 percent. We are also 

clarifying for the final rule for wet 

scrubbers on an autoclave, that facilities 

must establish the pressure drop range 

according to manufacturer’s 

specifications. 

8. Monitoring of Multiple Units Ducted 

to One Stack 

Comment: Commenters requested 

clarification that, for facilities that have 

two roasters ducted together through a 

shared mercury control system, the 

mercury concentration monitoring 

would be conducted on the combined 

exhaust stream. The commenters also 

requested clarification that the mercury 

concentration operating limit for two 

roasters that share a control system 

would be established during the 

simultaneous operation of the roasters 

in order to account for the combined 

mercury emissions from both roasters. 

Commenters also requested 

clarification that, for facilities with 

multiple process units ducted together 

through a shared carbon adsorber, the 

mercury concentration monitoring 

would be conducted on the combined 

exhaust stream. The commenters also 

requested clarification that the mercury 

concentration operating limit for a 

carbon adsorber for multiple units that 

share the carbon adsorber would be 

established during the simultaneous 

operations of all process units in order 

to account for the combined mercury 

emissions. 

Response: We agree with the 

commenters in general and have made 

the following clarifications in the final 

rule. If two roasters share a common 

control device and stack, the mercury 

concentration operating limit can be 

based on both roasters operating if 

possible. However, monitoring for 

mercury concentration must be 

performed at the frequency specified in 

the final rule whether only one or both 

roasters are operating. We also have 

clarified that, for multiple process units 

vented to a common carbon adsorber, 

the mercury concentration operating 

limit can be based on all units operating 

if possible. However, the ongoing 

mercury concentration monitoring must 

be performed at the frequency specified 

in the final rule for whatever units are 

operating at the time. 

9. Monitoring Mercury Concentration in 

Roaster Ore 

Comment: One commenter objected to 

the proposed requirement to conduct 

additional compliance testing if the 

mercury concentration in the ore fed to 

the roaster is higher than any 

concentration measured in the previous 

12 months. The commenter stated that 

there would not be an increase in the 

mercury emissions from their roasters 

because of the extensive series of 

mercury controls, some of which 

operate more efficiently at higher 

mercury loadings with unchanged stack 

emissions. In addition, the commenter 

noted that the rule does not provide 

details on how to measure the mercury 

ore concentration or what threshold of 

significance would be used to show an 

increase in ore mercury content 

occurred. The commenter concluded 

that the requirement would only 

provide extra cost and burden without 

any environmental benefit. 

Response: We agree with the 

commenter and have removed this 

requirement (§ 63.11647(a)(4)(iii) of 

proposed rule) from the final rule. We 

have no data showing that the mercury 

content of the ore has a significant effect 

on the performance of mercury 

scrubbers applied to roasters, which are 

designed to handle and operate 

efficiently for a range of mercury inlet 

concentrations. In addition, roasters 

condense and recover elemental 

mercury prior to the mercury scrubber, 

and any increase in mercury loading 

would likely result in an increase in the 

recovery of liquid elemental mercury. 

We have identified and require the 

monitoring of parameters associated 

with the scrubber chemistry, and 

maintaining these parameters within the 

established range for which the mercury 

scrubber was designed. This monitoring 

approach helps ensure that the mercury 

scrubbers are controlling mercury 

emission independent of variations in 

ore mercury content. 

VI. Summary of Environmental, 

Economic and Health Benefits 

For proposal, we estimated baseline 

mercury emissions to be 3,119 lb/yr 

based on the available emissions data 

and average process data for the period 

2007 to 2009. To estimate the impacts 

of the final rule, we have revised our 

baseline mercury emissions estimate to 

account for the recent installation of 

new mercury emission controls at two 

facilities and additional test data 

received since proposal. As a result of 

these changes, we now estimate baseline 

mercury emissions to be 2,636 lb/yr. We 

estimate the final MACT standard will 

reduce mercury emissions from gold 

mine ore processing and production by 

1,461 lb/yr from the baseline emissions 

levels of 2,636 lb/yr down to a level of 

1,176 lb/yr once this NESHAP is fully 

implemented. The annual emissions 

expected after the MACT standards are 

implemented (1,176 lb/yr) represent an 

estimated 77 percent reduction from 

2007 emissions (5,000 lb/yr), a 95 

percent reduction from the emissions 

level in 2001 (about 23,000 lb/yr), and 

more than 97 percent reduction from 

uncontrolled emissions levels (more 

than 37,000 lb/yr). The capital cost of 

emission controls is estimated as $36 

million with a total annualized cost of 

$8 million per year. The capital costs for 

monitoring, reporting, and 

recordkeeping are estimated as $0.5 to 

$1.0 million with a total annualized cost 

of $0.7 to $1.5 million per year, 

depending on the monitoring option 

that is chosen. The overall cost 

effectiveness is estimated to be about 

$6,300 per pound of mercury reduced. 

The cost of compliance is estimated to 

be less than 0.8 percent of sales for all 

affected firms. We therefore believe that 

the economic impact on an affected 

company would be insignificant. 

Electricity consumption is expected to 

increase by about 12,600 megawatthours per year due to increased fan 

capacity for carbon adsorbers and the 

installation of refrigeration units or 

condensers on a few process units. Nonhazardous solid waste (spent carbon 

containing mercury that must be 

regenerated or disposed of) would 

increase by about 7 tons per year. 


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Federal Register / Vol. 76, No. 33 / Thursday, February 17, 2011 / Rules and Regulations 9477 

VII. Statutory and Executive Order 

Reviews 

A. Executive Order 12866: Regulatory 

Planning and Review 

This action is a ‘‘significant regulatory 

action’’ under the terms of Executive 

Order 12866 (58 FR 51735, October 4, 

1993) because it may raise novel legal or 

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 

The information collection 

requirements in this final rule have been 

submitted for approval to OMB under 

the Paperwork Reduction Act, 44 U.S.C. 

3501 et seq. The Information Collection 

Request (ICR) document prepared by 

EPA has been assigned EPA ICR No. 

2383.01. 

The recordkeeping and reporting 

requirements in this final rule are based, 

in large part, on the information 

collection requirements in EPA’s 

NESHAP General Provisions (40 CFR 

part 63, subpart A). The recordkeeping 

and reporting requirements in the 

General Provisions are specifically 

authorized by section 114 of the CAA 

(42 U.S.C. 7414). All information other 

than emissions data submitted to EPA 

pursuant to the information collection 

requirements for which a claim of 

confidentiality is made is safeguarded 

according to CAA section 114(c) and 

EPA’s implementing regulations at 40 

CFR part 2, subpart B. 

This final NESHAP will require 

applicable one-time notifications 

according to the NESHAP General 

Provisions. In addition, owners or 

operators must submit annual 

notifications of compliance status and 

report any deviations in each 

semiannual reporting period. Records of 

all performance tests, measurements of 

feed input rates, monitoring data, and 

corrective actions will be required. 

The average annual burden for this 

information collection averaged over the 

first 3 years of this ICR is estimated to 

total 483 labor hours per year at a cost 

of approximately $26,847 per year for 

the 21 facilities that will be subject to 

this final rule, or approximately 23 

hours per year per facility. Capital costs 

are estimated as $1.0 million, operation 

and maintenance costs are estimated as 

$52,000 per year, and total annualized 

cost (including capital recovery) is 

estimated as $360,210 per year for this 

final rule’s information collection 

requirements. No costs or burden hours 

are estimated for new sources because 

none is projected for the next 3 years. 

Burden is defined at 5 CFR 1320.3(b). 

An agency may not conduct or 

sponsor, and a person is not required to 

respond to, a collection of information 

unless the collection displays a 

currently valid OMB control number. 

The OMB control numbers for EPA’s 

regulations in 40 CFR part 63 are listed 

in 40 CFR part 9. In addition, EPA is 

amending the table in 40 CFR part 9 of 

currently approved OMB control 

numbers for various regulations to list 

the regulatory citations for the 

information requirements contained in 

this final rule. 

C. Regulatory Flexibility Act 

The Regulatory Flexibility Act 

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 this rule would not have a 

significant economic impact on a 

substantial number of small entities. 

Small entities include small businesses, 

small not-for-profit enterprises, and 

small governmental jurisdictions. 

For the purposes of assessing the 

impacts of this final NESHAP on small 

entities, a small entity is defined as: 

(1) A small business whose parent 

company meets the Small Business 

Administration size standards for small 

businesses found at 13 CFR 121.201 

(less than 500 employees for gold mine 

ore processing and production 

facilities—NAICS 212221); (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 notfor-profit enterprise that is 

independently owned and operated and 

is not dominant in its field. 

After considering the economic 

impacts of this final rule on small 

entities, I certify that this action will not 

have a significant economic impact on 

a substantial number of small entities. 

This final rule is estimated to impact 

about 21 gold mine ore processing and 

production facilities, none of which are 

owned by small entities. Thus, there are 

no impacts to small entities from this 

final rule. Although this final rule will 

contain requirements for new sources, 

EPA expects few, if any, new sources to 

be constructed in the next several years. 

Therefore, EPA did not estimate the 

impacts for new affected sources for this 

final rule. 

Although this final rule will not have 

a significant economic impact on a 

substantial number of small entities, 

EPA nonetheless has tried to reduce the 

impact of this final rule on small and 

large entities. These standards establish 

emission limits that reflect practices and 

controls that are used throughout the 

industry and in many cases are already 

required by State operating permits. 

These standards also require only the 

essential monitoring, recordkeeping, 

and reporting needed to verify 

compliance. These final standards were 

developed based on information 

obtained from industry representatives 

in our surveys, consultation with 

business representatives and their trade 

association and other stakeholders. 

D. Unfunded Mandates Reform Act 

This final rule does not contain a 

Federal mandate that may result in 

expenditures of $100 million or more 

for State, local, and tribal governments, 

in the aggregate, or to the private sector 

in any one year. This final rule is not 

expected to impact State, local, or tribal 

governments. The total nationwide 

annualized cost of this final rule for 

affected industrial sources is $9.1 

million/yr. Thus, this final rule is not 

subject to the requirements of sections 

202 and 205 of the Unfunded Mandates 

Reform Act (UMRA). 

This final rule is also not subject to 

the requirements of section 203 of 

UMRA because it contains no regulatory 

requirements that might significantly or 

uniquely affect small governments. This 

final rule will not apply to such 

governments and will not impose any 

obligations upon them. 

E. Executive Order 13132: Federalism 

This action does not have federalism 

implications. It will not have substantial 

direct effects on the States, on the 

relationship between the national 

government and the States, or on the 

distribution of power and 

responsibilities among the various 

levels of government, as specified in 

Executive Order 13132. This final rule 

does not impose any requirements on 

state and local governments. Thus, 

Executive Order 13132 does not apply 

to this action. 

In the spirit of Executive Order 13132, 

and consistent with EPA policy to 

promote communications between EPA 

and State and local governments, EPA 

specifically solicited comment on this 

proposed action from State and local 

officials. 


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9478 Federal Register / Vol. 76, No. 33 / Thursday, February 17, 2011 / Rules and Regulations 

F. Executive Order 13175: Consultation 

and Coordination With Indian Tribal 

Governments 

This action does not have tribal 

implications, as specified in Executive 

Order 13175 (65 FR 67249, November 9, 

2000). This final rule imposes no 

requirements on tribal governments; 

thus, Executive Order 13175 does not 

apply to this action. Although EPA 

requested comment from tribal officials 

in developing this action, no comments 

on the proposal were received from 

tribal governments. However, the 

reductions in mercury emissions to the 

environment, which will be achieved by 

this final rule, will certainly benefit 

tribal populations within the vicinity of 

affected gold mine ore processing and 

production facilities. 

G. Executive Order 13045: Protection of 

Children From Environmental Health 

and Safety Risks 

EPA interprets Executive Order 13045 

(62 FR 19885, April 22, 1997) as 

applying only to those regulatory 

actions that are based on health or safety 

risks, such that the analysis required 

under section 5–501 of the Executive 

Order has the potential to influence the 

regulation. This action is not subject to 

Executive Order 13045 because it is 

based solely on technology 

performance. However, we note that the 

final rule will result in significant 

reductions in emissions of mercury, and 

thus will provide benefits to children’s 

health. 

H. Executive Order 13211: Actions 

Concerning Regulations That 

Significantly Affect Energy Supply, 

Distribution, or Use 

This action 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. We have 

concluded that this final rule will not 

likely have any significant adverse 

energy effects because energy 

consumption would increase by only 

12,600 megawatt-hours per year. 

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 (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, business practices) that are 

developed or adopted by voluntary 

consensus standards bodies. NTTAA 

directs EPA to provide Congress, 

through OMB, explanations when the 

Agency decides not to use available and 

applicable VCS. 

This final rulemaking involves 

technical standards. EPA decided to use 

ASME PTC 19.10–1981, ‘‘Flue and 

Exhaust Gas Analyses,’’ for its manual 

methods of measuring the oxygen or 

carbon dioxide content of the exhaust 

gas. These parts of ASME PTC 19.10– 

1981 are acceptable alternatives to EPA 

Method 3B. This standard is available 

from the American Society of 

Mechanical Engineers (ASME), Three 

Park Avenue, New York, NY 10016– 

5990. 

Another VCS, ASTM D6784–02, 

‘‘Standard Test Method for Elemental, 

Oxidized, Particle-Bound and Total 

Mercury in Flue Gas Generated from 

Coal-Fired Stationary Sources (Ontario 

Hydro Method)’’ is an acceptable 

alternative to EPA Method 29 for this 

NESHAP if approved by the permit 

authority. This performance test method 

is available from ASTM International. 

See http://www.astm.org/. 

EPA has also decided to use EPA 

Methods 1, 1A, 2, 2A, 2C, 2D, 2F, 2G, 

3, 3A, 3B, 4, 12A, 12B, 29, 30B, SW–846 

Method 7471B, ‘‘Mercury in Solid or 

Semisolid Waste (Manual Cold-Vapor 

Technique),’’ (incorporated by 

reference—see § 63.14) and ASTM 

D6784–02, ‘‘Standard Test Method for 

Elemental, Oxidized, Particle-Bound 

and Total Mercury in Flue Gas 

Generated from Coal-Fired Stationary 

Sources,’’ (incorporated by reference— 

see § 63.14). Although the Agency has 

identified 14 VCS as being potentially 

applicable to these methods cited in this 

rule, we have decided not to use these 

standards in this final rulemaking. The 

use of these VCS would have been 

impractical because they do not meet 

the objectives of the standards cited in 

this rule. The search and review results 

are in the docket for this final rule. 

Under section 63.7(f) and section 

63.8(f) of Subpart A of the General 

Provisions, a source may apply to EPA 

for permission to use alternative test 

methods or alternative monitoring 

requirements in place of any required 

testing methods, performance 

specifications, or procedures in the final 

rule. 

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 final 

rule will not have disproportionately 

high and adverse human health or 

environmental effects on minority or 

low-income populations because it will 

increase the level of environmental 

protection for all affected populations 

without having any disproportionately 

high and adverse human health or 

environmental effects on any 

population, including any minority or 

low-income population. 

Additionally, the Agency has 

reviewed this rule to determine if there 

were any existing disproportionately 

high and adverse human health or 

environmental effects on minority or 

low-income populations that could be 

mitigated by this rulemaking. An 

analysis of demographic data showed 

that the areas in closest proximity to 

gold mines are very rural, with low total 

populations. The population total for 

block groups which centers are within 

3 miles of a gold mine facility is 1,580. 

At the three mile radius, minority 

populations and children’s populations 

are underrepresented when compared to 

national averages, while populations 

living below poverty are 

overrepresented. The aggregate average 

percentages for these groups are 26.3 

percent, 30.5 percent, and 26 percent for 

minority populations, populations 

living below poverty, and children’s 

populations, respectively. These 

averages are compared to national 

averages across block groups for these 

populations which are 31.8 percent, 

12.5 percent, and 25.7 percent. There 

were only two block groups with centers 

within 3 miles of any gold mine, and the 

total population living below poverty 

was found to be 492. 

In determining the aggregate 

demographic makeup of the 

communities near affected sources, EPA 

used census data at the block group 

level to identify demographics of the 

populations considered to be living near 

affected sources, such that they have 

notable exposures to current emissions 

from these sources. In this approach, 

EPA reviewed the distributions of 

different socio-demographic groups in 

the locations of the expected emission 

reductions from this rule. The review 


jlentini on DSKJ8SOYB1PROD with RULES2
Federal Register / Vol. 76, No. 33 / Thursday, February 17, 2011 / Rules and Regulations 9479 

5U.S. GAO (Government Accountability Office). 

Demographics of People Living Near Waste 

Facilities. Washington, DC: Government Printing 

Office; 1995. 

6Mohai P, Saha R. ‘‘Reassessing Racial and Socioeconomic Disparities in Environmental Justice 

Research’’. Demography. 2006;43(2):383–399. 

7Mennis J. ‘‘Using Geographic Information 

Systems to Create and Analyze Statistical Surfaces 

of Populations and Risk for Environmental Justice 

Analysis’’. Social Science Quarterly, 

2002;83(1):281–297. 

8Bullard RD, Mohai P, Wright B, Saha R, et al. 

Toxic Waste and Race at Twenty 1987–2007. United 

Church of Christ. March 2007. 

9The results of the demographic analysis are 

presented in ‘‘Review of Environmental Justice 

Impacts for Gold Mines’’, December 2010, a copy of 

which is available in the docket. 

identified those census block groups 

within a circular distance of a 1, 3, and 

5 miles of affected sources and 

determined the demographic and socioeconomic composition (e.g., race, 

income, education, etc.) of these census 

block groups. The radius of 3 miles (or 

approximately 5 kilometers) has been 

used in other demographic analyses 

focused on areas around potential 

sources.5678 Gold mine facilities were 

assumed to have an average area of 7 

square miles and buffered distances 

were calculated beyond the 7 square 

mile area to count populations not 

within the mine boundaries. EPA’s 

demographic analysis has shown that 

these areas have an overrepresentation 

of populations below poverty, and an 

underrepresentation of minority and 

children’s populations.9

This action establishes national 

emission standards for new and existing 

gold mines. The EPA estimates that 

there are approximately 23 such 

locations covered by this rule. The rule 

will reduce emissions of mercury (Hg), 

and as a result have positive health and 

welfare benefits to sustenance fishing 

communities, many of which are often 

considered to have environmental 

justice concerns. 

EPA defines ‘‘Environmental Justice’’ 

to include meaningful involvement of 

all people regardless of race, color, 

national origin, or income with respect 

to the development, implementation, 

and enforcement of environmental laws, 

regulations, and policies. To promote 

meaningful involvement, EPA has 

developed a communication and 

outreach strategy to ensure that 

interested communities have access to 

this rule and are aware of its content. 

EPA will publicize the rulemaking via 

EJ newsletters, Tribal newsletters, EJ 

listservs, and the Internet, including 

EPA’s Office of Policy’s Rulemaking 

Gateway Web site (http:// 

yosemite.epa.gov/opei/RuleGate.nsf/). 

EPA will also conduct targeted outreach 

to EJ communities as appropriate. 

Outreach activities may include 

providing general rulemaking fact sheets 

(e.g., why is this important for my 

community) for EJ community groups 

and conducting conference calls with 

interested communities. In addition, 

State and Federal permitting 

requirements will provide State and 

local governments and members of 

affected communities the opportunity to 

provide comments on the permit 

conditions associated with permitting 

the sources affected by this rulemaking. 

Overall, this final rule is expected to 

reduce mercury emissions from gold 

mine ore processing and production 

facilities and thus decrease the amount 

of such emissions to which all affected 

populations are exposed. 

K. Congressional Review Act 

The Congressional Review Act, 5 

U.S.C. 801 et seq., as added by the Small 

Business Regulatory Enforcement 

Fairness Act of 1996, generally provides 

that before a rule may take effect, the 

agency promulgating the rule must 

submit a rule report, which includes a 

copy of the rule, to each House of the 

Congress and to the Comptroller General 

of the United States. EPA will submit a 

report containing this final rule and 

other required information to the U.S. 

Senate, the U.S. House of 

Representatives, and the Comptroller 

General of the United States prior to 

publication of this final rule in the 

Federal Register. A major rule cannot 

take effect until 60 days after it is 

published in the Federal Register. This 

action is not a ‘‘major rule’’ as defined 

by 5 U.S.C. 804(2). This final rule will 

be effective on February 17, 2011. 

List of Subjects 

40 CFR Part 9 

Environmental protection, Reporting 

and recordkeeping requirements. 

40 CFR Part 63 

Environmental protection, Air 

pollution control, Hazardous 

substances, Incorporation by reference, 

Reporting and recordkeeping 

requirements. 

Dated: December 16, 2010. 

Lisa P. Jackson, 

Administrator. 

For the reasons stated in the 

preamble, title 40, chapter I, of the Code 

of Federal Regulations is amended as 

follows: 

PART 9—[AMENDED] 

■ 1. The authority citation for part 9 

continues to read as follows: 

Authority: 7 U.S.C. 135, et seq., 136–136y; 

15 U.S.C. 2001, 2003, 2005, 2006, 2601–2671; 

21 U.S.C. 331j, 346a, 348; 31 U.S.C. 9701; 33 

U.S.C. 1251, et seq., 1311, 1313d, 1314, 1318, 

1321, 1326, 1330, 1342, 1344, 1345(d) and 

(e), 1361; E.O. 11735, 38 FR 21243, 3 CFR, 

1971–1975 Comp. p. 973; 42 U.S.C. 241, 

242b, 243, 246, 300f, 300g, 300g–1, 300g–2, 

300g–3, 300g–4, 300g–5, 300g–6, 300j–1, 

300j–2, 300j–3, 300j–4, 300j–9, 1857, et seq., 

6901–6992k, 7401–7671q, 7542, 9601–9657, 

11023, 11048. 

Subpart A—[Amended] 

* * * * * 

■ 2. The table in § 9.1 is amended by 

adding an entry in numerical order for 

‘‘63.11647–63.11648’’ under the heading 

‘‘National Emission Standards for 

Hazardous Air Pollutants for Source 

Categories’’ to read as follows: 

§ 9.1 OMB Approvals under the Paperwork 

Reduction Act. 

* * * * * 

40 CFR citation OMB control 

No. 

* * * * * 

National Emission Standards for Hazardous 

Air Pollutants for Source Categories 3

* * * * * 

63.11647–63.11648 .................. 2060–NEW 

* * * * * 

*****

3The ICRs referenced in this section of the 

table encompass the applicable general provisions contained in 40 CFR part 63, subpart A, 

which are not independent information collection requirements. 

* * * * * 

PART 63—[AMENDED] 

■ 3. The authority citation for part 63 

continues to read as follows: 

Authority: 42 U.S.C. 7401 et seq. 

Subpart A—[Amended] 

■ 4. Section 63.14 is amended by adding 

paragraph (b)(66), revising paragraph 

(i)(1), and adding paragraph (k)(1)(v) to 

read as follows: 

§ 63.14 Incorporation by reference. 

* * * * * 

(b) * * * 

(66) ASTM D6784–02 (Reapproved 

2008), Standard Test Method for 

Elemental, Oxidized, Particle-Bound 

and Total Mercury in Flue Gas 

Generated from Coal-Fired Stationary 

Sources (Ontario Hydro Method), 


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approved April 1, 2008, IBR approved 

for § 63.11646(a)(1)(vi), 

§ 63.11647(a)(1)(ii), § 63.11647(a)(3)(ii), 

and § 63.11647(d). 

* * * * * 

(i) * * * 

(1) ANSI/ASME PTC 19.10–1981, 

Flue and Exhaust Gas Analyses [Part 10, 

Instruments and Apparatus], issued 

August 31, 1981 IBR approved for 

§§ 63.309(k)(1)(iii), 63.865(b), 

63.3166(a)(3), 63.3360(e)(1)(iii), 

63.3545(a)(3), 63.3555(a)(3), 

63.4166(a)(3), 63.4362(a)(3), 

63.4766(a)(3), 63.4965(a)(3), 

63.5160(d)(1)(iii), 63.9307(c)(2), 

63.9323(a)(3), 63.11148(e)(3)(iii), 

63.11155(e)(3), 63.11162(f)(3)(iii) and 

(f)(4), 63.11163(g)(1)(iii) and (g)(2), 

63.11410(j)(1)(iii), 63.11551(a)(2)(i)(C), 

63.11646(a)(1)(iii), table 5 to subpart 

DDDDD of this part, and table 1 to 

subpart ZZZZZ of this part. 

* * * * * 

(k) * * * 

(1) * * * 

(v) SW–846 Method 74741B, Revision 

2, ‘‘Mercury in Solid or Semisolid Waste 

(Manual Cold-Vapor Technique)’’ 

February 2007, IBR approved for 

§ 63.11647(f)(2). 

* * * * * 

■ 5. Part 63 is amended by adding 

subpart EEEEEEE to read as follows: 

Subpart EEEEEEE—National Emission 

Standards for Hazardous Air Pollutants: 

Gold Mine Ore Processing and Production 

Area Source Category 

Applicability and Compliance Dates 

Sec. 

63.11640 Am I subject to this subpart? 

63.11641 What are my compliance dates? 

Standards and Compliance Requirements 

63.11645 What are my mercury emission 

standards? 

63.11646 What are my compliance 

requirements? 

63.11647 What are my monitoring 

requirements? 

63.11648 What are my notification, 

reporting, and recordkeeping 

requirements? 

Other Requirements and Information 

63.11650 What General Provisions apply to 

this subpart? 

63.11651 What definitions apply to this 

subpart? 

63.11652 Who implements and enforces 

this subpart? 

63.11653 [Reserved] 

Tables to Subpart EEEEEEE of Part 63 

Table 1 to Subpart EEEEEEE of Part 63— 

Applicability of General Provisions to 

Subpart EEEEEEE 

Subpart EEEEEEE—National Emission 

Standards for Hazardous Air 

Pollutants: Gold Mine Ore Processing 

and Production Area Source Category 

Applicability and Compliance Dates 

§ 63.11640 Am I subject to this subpart? 

(a) You are subject to this subpart if 

you own or operate a gold mine ore 

processing and production facility as 

defined in § 63.11651, that is an area 

source. 

(b) This subpart applies to each new 

or existing affected source. The affected 

sources are each collection of ‘‘ore 

pretreatment processes’’ at a gold mine 

ore processing and production facility, 

each collection of ‘‘carbon processes 

with mercury retorts’’ at a gold mine ore 

processing and production facility, each 

collection of ‘‘carbon processes without 

mercury retorts’’ at a gold mine ore 

processing and production facility, and 

each collection of ‘‘non-carbon 

concentrate processes’’ at a gold mine 

ore processing and production facility, 

as defined in § 63.11651. 

(1) An affected source is existing if 

you commenced construction or 

reconstruction of the affected source on 

or before April 28, 2010. 

(2) An affected source is new if you 

commenced construction or 

reconstruction of the affected source 

after April 28, 2010. 

(c) This subpart does not apply to 

research and development facilities, as 

defined in section 112(c)(7) of the Clean 

Air Act (CAA). 

(d) If you own or operate a source 

subject to this subpart, you must have 

or you must obtain a permit under 40 

CFR part 70 or 40 CFR part 71. 

§ 63.11641 What are my compliance 

dates? 

(a) If you own or operate an existing 

affected source, you must comply with 

the applicable provisions of this subpart 

no later than February 17, 2014. 

(b) If you own or operate a new 

affected source, and the initial startup of 

your affected source is on or before 

February 17, 2011, you must comply 

with the provisions of this subpart no 

later than February 17, 2011. 

(c) If you own or operate a new 

affected source, and the initial startup of 

your affected source is after February 

17, 2011, you must comply with the 

provisions of this subpart upon startup 

of your affected source. 

Standards and Compliance 

Requirements 

§ 63.11645 What are my mercury emission 

standards? 

(a) For existing ore pretreatment 

processes, you must emit no more than 

127 pounds of mercury per million tons 

of ore processed. 

(b) For existing carbon processes with 

mercury retorts, you must emit no more 

than 2.2 pounds of mercury per ton of 

concentrate processed. 

(c) For existing carbon processes 

without mercury retorts, you must emit 

no more than 0.17 pounds of mercury 

per ton of concentrate processed. 

(d) For existing non-carbon 

concentrate processes, you must emit no 

more than 0.2 pounds of mercury per 

ton of concentrate processed. 

(e) For new ore pretreatment 

processes, you must emit no more than 

84 pounds of mercury per million tons 

of ore processed. 

(f) For new carbon processes with 

mercury retorts, you must emit no more 

than 0.8 pounds of mercury per ton of 

concentrate processed. 

(g) For new carbon processes without 

mercury retorts, you must emit no more 

than 0.14 pounds of mercury per ton of 

concentrate processed. 

(h) For new non-carbon concentrate 

processes, you must emit no more than 

0.1 pounds of mercury per ton of 

concentrate processed. 

(i) The standards set forth in this 

section apply at all times. 

§ 63.11646 What are my compliance 

requirements? 

(a) Except as provided in paragraph 

(b) of this section, you must conduct a 

mercury compliance emission test 

within 180 days of the compliance date 

for all process units at new and existing 

affected sources according to the 

requirements in paragraphs (a)(1) 

through (a)(13) of this section. This 

compliance testing must be repeated 

annually thereafter, with no two 

consecutive annual compliance tests 

occurring less than 3 months apart or 

more than 15 months apart. 

(1) You must determine the 

concentration of mercury and the 

volumetric flow rate of the stack gas 

according to the following test methods 

and procedures: 

(i) Method 1 or 1A (40 CFR part 60, 

appendix A–1) to select sampling port 

locations and the number of traverse 

points in each stack or duct. Sampling 

sites must be located at the outlet of the 

control device (or at the outlet of the 

emissions source if no control device is 

present) and prior to any releases to the 

atmosphere. 

(ii) Method 2, 2A, 2C, 2D, 2F (40 CFR 

part 60, appendix A–1), or Method 2G 

(40 CFR part 60, appendix A–2) to 

determine the volumetric flow rate of 

the stack gas. 

(iii) Method 3, 3A, or 3B (40 CFR part 

60, appendix A–2) to determine the dry 


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molecular weight of the stack gas. You 

may use ANSI/ASME PTC 19.10, ‘‘Flue 

and Exhaust Gas Analyses’’ 

(incorporated by reference-see § 63.14) 

as an alternative to EPA Method 3B. 

(iv) Method 4 (40 CFR part 60, 

appendix A–3) to determine the 

moisture content of the stack gas. 

(v) Method 29 (40 CFR part 60, 

appendix A–8) to determine the 

concentration of mercury, except as 

provided in paragraphs (a)(1)(vi) and 

(vii) of this section. 

(vi) Upon approval by the permitting 

authority, ASTM D6784; ‘‘Standard Test 

Method for Elemental, Oxidized, 

Particle-Bound and Total Mercury in 

Flue Gas Generated from Coal-Fired 

Stationary Sources (Ontario Hydro 

Method)’’ (incorporated by reference— 

see § 63.14) may be used as an 

alternative to Method 29 to determine 

the concentration of mercury. 

(vii) Upon approval by the permitting 

authority, Method 30B (40 CFR part 60, 

appendix A–8) may be used as an 

alternative to Method 29 to determine 

the concentration of mercury for those 

process units with relatively low 

particulate-bound mercury as specified 

in Section 1.2 of Method 30B. 

(2) A minimum of three test runs must 

be conducted for each performance test 

of each process unit. Each test run 

conducted with Method 29 must collect 

a minimum sample volume of 0.85 dry 

standard cubic meters (30 dry standard 

cubic feet). If conducted with Method 

30B or ASTM D6784, determine sample 

time and volume according to the 

testing criteria set forth in the relevant 

method. If the emission testing results 

for any of the emission points yields a 

non-detect value, then the minimum 

detection limit (MDL) must be used to 

calculate the mass emissions rate (lb/hr) 

used to calculate the emissions factor 

(lb/ton) for that emission point and, in 

turn, for calculating the sum of the 

emissions (in units of pounds of 

mercury per ton of concentrate, or 

pounds of mercury per million tons of 

ore) for all emission points subject to 

the emission standard for determining 

compliance. If the resulting mercury 

emissions are greater than the MACT 

emission standard, the owner or 

operator may use procedures that 

produce lower MDL results and repeat 

the mercury emissions testing one 

additional time for any emission point 

for which the measured result was 

below the MDL. If this additional testing 

is performed, the results from that 

testing must be used to determine 

compliance (i.e., there are no additional 

opportunities allowed to lower the 

MDL). 

(3) Performance tests shall be 

conducted under such conditions as the 

Administrator specifies to the owner or 

operator based on representative 

performance of the affected source for 

the period being tested. Upon request, 

the owner or operator shall make 

available to the Administrator such 

records as may be necessary to 

determine the conditions of 

performance tests. Performance tests 

must be conducted under operating 

conditions (including process or 

production throughputs) that are based 

on representative performance. Record 

and report to the permit authority the 

process throughput for each test run. 

For sources with multiple emission 

units (e.g., two roasters, or a furnace, 

electrowinning circuit and a mercury 

retort) ducted to a common control 

device and stack, compliance testing 

must be performed either by conducting 

a single compliance test with all 

affected emissions units in operation or 

by conducting a separate compliance 

test on each emissions unit. 

Alternatively, the owner or operator 

may request approval from the permit 

authority for an alternative testing 

approach. If the units are tested 

separately, any emissions unit that is 

not tested initially must be tested as 

soon as is practicable. If the 

performance test is conducted when all 

affected units are operating, then the 

number of hours of operation used for 

calculating emissions pursuant to 

paragraphs (a)(6) and (7) of this section 

must be the total number of hours for 

the unit that has the greatest total 

operating hours for that period of time, 

or based on an appropriate alternative 

method approved by the permit 

authority to account for the hours of 

operation for each separate unit in these 

calculations. 

(4) Calculate the mercury emission 

rate (lb/hr), based on the average of 3 

test run values, for each process unit (or 

combination of units that are ducted to 

a common stack and are tested when all 

affected sources are operating pursuant 

to paragraph (a)(3) of this section) using 

Equation (1) of this section: 

Where: 

E = mercury emissions in lb/hr; 

Cs = concentration of mercury in the stack 

gas, in grains per dry standard cubic foot 

(gr/dscf); 

Qs = volumetric flow rate of the stack gas, in 

dry standard cubic feet per hour; and 

K = conversion factor for grains (gr) to 

pounds (lb), 1.43 × 10-4. 

(5) Monitor and record the number of 

one-hour periods each process unit 

operates during each month. 

(6) For the initial compliance 

determination for both new and existing 

sources, determine the total mercury 

emissions for all the full calendar 

months between the compliance date 

and the date of the initial compliance 

test by multiplying the emission rate in 

lb/hr for each process unit (or 

combination of units ducted to a 

common stack that are tested together) 

by the number of one-hour periods each 

process unit (or the unit that had the 

greatest total operating hours among the 

combination of multiple units with one 

stack that are tested together, or an 

alternative method approved by the 

permit authority, pursuant to paragraph 

(a)(3) of this section) operated during 

those full calendar months prior to the 

initial compliance test. This initial 

period must include at least 1 full 

month of operations. After the initial 

compliance test, for subsequent 

compliance tests, determine the 

mercury mass emissions for the 12 full 

calendar months prior to the 

compliance test in accordance with the 

procedures in paragraph (a)(7) of this 

section. Existing sources may use a 

previous emission test for their initial 

compliance determination in lieu of 

conducting a new test if the test was 

conducted within one year of the 

compliance date using the methods 

specified in paragraphs (a)(1) through 

(a)(4) of this section, and the tests were 

representative of current operating 

processes and conditions. If a previous 

test is used for their initial compliance 

determination, 3 to 12 full months of 

data on hours of operation and 

production (i.e., million tons of ore or 

tons of concentrate), including the 

month the test was conducted, must be 

used to calculate the emissions rate (in 

units of pounds of mercury per million 

tons of ore for the ore pretreatment 

affected sources, or in units of pounds 

of mercury per tons of concentrate for 

the other affected sources). 

(7) For compliance determinations 

following the initial compliance test for 

new and existing sources, determine the 

total mercury mass emissions for each 

process unit for the 12 full calendar 


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months preceding the performance test 

by multiplying the emission rate in lb/ 

hr for each process unit (or combination 

of units ducted to a common stack that 

are tested together) by the number of 

one-hour periods each process unit (or 

the unit that had the greatest total 

operating hours among the combination 

of multiple units with one stack that are 

tested together, or an alternative method 

approved by the permit authority, 

pursuant to paragraph (a)(3) of this 

section) operated during the 12 full 

calendar months preceding the 

completion of the performance tests. 

(8) You must install, calibrate, 

maintain and operate an appropriate 

weight measurement device, mass flow 

meter, or densitometer and volumetric 

flow meter to measure ore throughput 

for each roasting operation and 

autoclave and calculate hourly, daily 

and monthly totals in tons of ore 

according to paragraphs (a)(8)(i) and 

(a)(8)(ii) of this section. 

(i) Measure the weight or the density 

and volumetric flow rate of the oxidized 

ore slurry as it exits the roaster 

oxidation circuit(s) and before the 

carbon-in-leach tanks. Alternatively, the 

weight of the ore can be measured ‘‘as 

fed’’ if approved by the permit authority 

as an acceptable equivalent method to 

measure amount of ore processed. 

(ii) Measure the weight or the density 

and volumetric flow rate of the ore 

slurry as it is fed to the autoclave(s). 

Alternatively, the weight or the density 

and volumetric flow rate of the oxidized 

ore slurry can be measured as it exits 

the autoclave and before the carbon-inleach tanks if approved by the permit 

authority as an acceptable equivalent 

method to measure amount of ore 

processed. 

(9) Measure the weight of concentrate 

(produced by electrowinning, Merrill 

Crowe process, gravity feed, or other 

methods) using weigh scales for each 

batch prior to processing in mercury 

retorts or melt furnaces. For facilities 

with mercury retorts, the concentrate 

must be weighed in the same state and 

condition as it is when fed to the 

mercury retort. For facilities without 

mercury retorts, the concentrate must be 

weighed prior to being fed to the melt 

furnace before drying in any ovens. For 

facilities that ship concentrate offsite, 

measure the weight of concentrate as 

shipped offsite. You must keep accurate 

records of the weights of each batch of 

concentrate processed and calculate, 

and record the total weight of 

concentrate processed each month. 

(10) You must maintain the systems 

for measuring density, volumetric flow 

rate, and weight within ± 5 percent 

accuracy. You must describe the 

specific equipment used to make 

measurements at your facility and how 

that equipment is periodically 

calibrated. You must also explain, 

document, and maintain written 

procedures for determining the accuracy 

of the measurements and make these 

written procedures available to your 

permitting authority upon request. You 

must determine, record, and maintain a 

record of the accuracy of the measuring 

systems before the beginning of your 

initial compliance test and during each 

subsequent quarter of affected source 

operation. 

(11) Record the weight in tons of ore 

for ore pretreatment processes and 

concentrate for carbon processes with 

mercury retorts, carbon processes 

without mercury retorts, and for noncarbon concentrate processes on a daily 

and monthly basis. 

(12) Calculate the emissions from 

each new and existing affected source 

for the sum of all full months between 

the compliance date and the date of the 

initial compliance test in pounds of 

mercury per ton of process input using 

the procedures in paragraphs (a)(12)(i) 

through (a)(12)(iv) of this section to 

determine initial compliance with the 

emission standards in § 63.11645. This 

must include at least 1 full month of 

data. Or, if a previous test is used 

pursuant to paragraph (a)(6) of this 

section for the initial compliance test, 

use a period of time pursuant to 

paragraph (a)(6) of this section to 

calculate the emissions for the affected 

source. After this initial compliance test 

period, determine annual compliance 

using the procedures in paragraph 

(a)(13) of this section for existing 

sources. 

(i) For ore pretreatment processes, 

divide the sum of mercury mass 

emissions (in pounds) from all roasting 

operations and autoclaves during the 

number of full months between the 

compliance date and the initial 

compliance test by the sum of the total 

amount of gold mine ore processed (in 

million tons) in these process units 

during those same full months following 

the compliance date. Or, if a previous 

test is used to determine initial 

compliance, pursuant to paragraph 

(a)(6) of this section, then the same 3 to 

12 full months of production data (i.e., 

million tons of ore) and hours of 

operation referred to in paragraph (a)(6) 

of this section, must be used to 

determine the emissions in pounds of 

mercury per million tons of ore. 

(ii) For carbon processes with 

mercury retorts, divide the sum of 

mercury mass emissions (in pounds) 

from all carbon kilns, preg tanks, 

electrowinning, mercury retorts, and 

melt furnaces during the initial number 

of full months between the compliance 

date and the initial compliance tests by 

the total amount of concentrate (in tons) 

processed in these process units during 

those same full months following the 

compliance date. If a previous test is 

used to determine initial compliance, 

pursuant to paragraph (a)(6) of this 

section, then the same 3 to 12 full 

months of production data (i.e., tons of 

concentrate) and hours of operation 

referred to in paragraph (a)(6) of this 

section, must be used to determine the 

emissions in pounds of mercury per 

tons of concentrate. 

(iii) For carbon processes without 

mercury retorts, divide the sum of 

mercury mass emissions (in pounds) 

from all carbon kilns, preg tanks, 

electrowinning, and melt furnaces 

during the initial number of full months 

between the compliance date and the 

initial compliance tests by the total 

amount of concentrate (in tons) 

processed in these process units during 

those same full months following the 

compliance date. If a previous test is 

used to determine initial compliance, 

pursuant to paragraph (a)(6) of this 

section, then the same 3 to 12 full 

months of production data (i.e., tons of 

concentrate) and hours of operation 

referred to in paragraph (a)(6) of this 

section, must be used to determine the 

emissions in pounds of mercury per 

tons of concentrate. 

(iv) For non-carbon concentrate 

processes, divide the sum of mercury 

mass emissions (in pounds) from 

mercury retorts and melt furnaces 

during the initial number of full months 

between the compliance date and the 

initial compliance tests by the total 

amount of concentrate (in tons) 

processed in these process units during 

those same full months following the 

compliance date. If a previous test is 

used to determine initial compliance, 

pursuant to paragraph (a)(6) of this 

section, then the same 3 to 12 full 

months of production data (i.e., tons of 

concentrate) and hours of operation 

referred to in paragraph (a)(6) of this 

section, must be used to determine the 

emissions in pounds of mercury per 

tons of concentrate. 

(13) After the initial compliance test, 

calculate the emissions from each new 

and existing affected source for each 

12-month period preceding each 

subsequent compliance test in pounds 

of mercury per ton of process input 

using the procedures in paragraphs 

(a)(13)(i) through (iv) of this section to 

determine compliance with the 

emission standards in § 63.11645. 

(i) For ore pretreatment processes, 

divide the sum of mercury mass 


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emissions (in pounds) from all roasting 

operations and autoclaves in the 

12-month period preceding a 

compliance test by the sum of the total 

amount of gold mine ore processed (in 

million tons) in that 12-month period. 

(ii) For carbon processes with 

mercury retorts, divide the sum of 

mercury mass emissions (in pounds) 

from all carbon kilns, preg tanks, 

electrowinning, mercury retorts, and 

melt furnaces in the 12-month period 

preceding a compliance test by the total 

amount of concentrate (in tons) 

processed in these process units in that 

12-month period. 

(iii) For carbon processes without 

mercury retorts, divide the sum of 

mercury mass emissions (in pounds) 

from all carbon kilns, preg tanks, 

electrowinning, and melt furnaces in the 

12-month period preceding a 

compliance test by the total amount of 

concentrate (in tons) processed in these 

process units in that 12-month period. 

(iv) For non-carbon concentrate 

processes, divide the sum of mercury 

mass emissions (in pounds) from 

mercury retorts and melt furnaces in the 

12-month period preceding a 

compliance test by the total amount of 

concentrate (in tons) processed in these 

process units in that 12-month period. 

(b) At all times, you must operate and 

maintain any affected source, including 

associated air pollution control 

equipment and monitoring equipment, 

in a manner consistent with safety and 

good air pollution control practices for 

minimizing emissions. Determination of 

whether such operation and 

maintenance procedures are being used 

will be based on information available 

to the Administrator which may 

include, but is not limited to, 

monitoring results, review of operation 

and maintenance procedures, review of 

operation and maintenance records, and 

inspection of the source. 

§ 63.11647 What are my monitoring 

requirements? 

(a) Except as provided in paragraph 

(a)(5) of this section, you must monitor 

each roaster for mercury emissions 

using one of the procedures in 

paragraphs (a)(1), (a)(2), or (a)(3) of this 

section and establish operating limits 

for mercury concentration as described 

in paragraph (a)(4) of this section. 

(1) Perform sampling and analysis of 

the roaster’s exhaust for mercury 

concentration using EPA Performance 

Specification 12B (40 CFR part 60, 

appendix B and Procedure 5 of 

appendix F) or EPA Method 30B (40 

CFR part 60, appendix A–8) at least 

twice per month. A minimum of two 

measurements must be taken per month 

that are at least 11 days apart from other 

consecutive tests. The mercury 

concentration must be maintained 

below the operating limit established in 

paragraph (a)(4) of this section. The 

results of the sampling must be obtained 

within 72 hours of the time the sample 

is taken. 

(i) To determine the appropriate 

sampling duration, you must review the 

available data from previous stack tests 

to determine the upper 99th percentile 

of the range of mercury concentrations 

in the exit stack gas. Based on this 

upper end of expected concentrations, 

select an appropriate sampling duration 

that is likely to provide a valid sample 

and not result in breakthrough of the 

sampling tubes. If breakthrough of the 

sampling tubes occurs, you must resample within 7 days using a shorter 

sampling duration. 

(ii) If any mercury concentration 

measurement from the twice per month 

sampling with PS 12B or Method 30B is 

higher than the operating limit, the 

exceedance must be reported to the 

permit authority as a deviation and 

corrective actions must be implemented 

within 48 hours upon receipt of the 

sampling results. Moreover, within 96 

hours of the exceedance, the owner or 

operator must measure the 

concentration again (with PS 12B (40 

CFR part 60, appendix B and Procedure 

5 of appendix F), Method 30B or 

Method 29 (40 CFR part 60, appendix 

A–8), or ASTM D6784(incorporated by 

reference—see § 63.14)) and 

demonstrate to the permit authority that 

the mercury concentration is no higher 

than the operating limit, or inform the 

permit authority that the limit continues 

to be exceeded. If the measured mercury 

concentration exceeds the operating 

limit for mercury concentration after 

these 96 hours, the exceedance must be 

reported as a deviation within 24 hours 

to the permitting authority. The owner 

or operator must conduct a full 

compliance test pursuant to 

§ 63.11646(a) for the roaster operations 

within 40 days to determine if the 

affected source is in compliance with 

the MACT emission standard. For 

facilities that have roasters and 

autoclaves, the owner or operator can 

use the results of the previous 

compliance test for the autoclaves to 

determine the emissions for those 

process units to be used in the 

calculations of the emissions for the 

affected source. If the source is 

determined to be in compliance, the 

compliance test may also be used to 

establish a new operating limit for 

mercury concentration (in accordance 

with paragraph (e) of this section). 

(2) Install, operate, calibrate, and 

maintain a continuous emissions 

monitoring system (CEMS) to 

continuously measure the mercury 

concentration in the final exhaust 

stream from each roaster according to 

the requirements of Performance 

Specification 12A (40 CFR part 60, 

appendix B) except that calibration 

standards traceable to the National 

Institute of Standards and Technology 

are not required. You must perform a 

data accuracy assessment of the CEMS 

according to section 5 of Appendix F in 

part 60 and follow the applicable 

monitoring requirements in § 63.8 as 

provided in Table 1 to subpart 

EEEEEEE. 

(i) You must continuously monitor 

the daily average mercury concentration 

from the roaster and maintain the daily 

average concentration below the 

operating limit established in paragraph 

(a)(4) of this section. 

(ii) If the daily average mercury 

concentration from the CEMs is higher 

than the operating limit, the exceedance 

must be reported to the permit authority 

as a deviation and corrective actions 

must be implemented within 48 hours 

upon receipt of the sampling results. 

Moreover, within 96 hours of the 

exceedance, the owner or operator must 

measure the concentration again (with 

the CEMs (40 CFR part 60, appendix B 

and Procedure 5 of appendix F) and 

demonstrate to the permit authority that 

the mercury concentration is no higher 

than the operating limit, or inform the 

permit authority that the limit continues 

to be exceeded. If the measured mercury 

concentration exceeds the operating 

limit for mercury concentration after 

these 96 hours, the exceedance must be 

reported as a deviation within 24 hours 

to the permitting authority, and the 

owner or operator must conduct a full 

compliance test pursuant to 

§ 63.11646(a) for the roaster operations 

within 40 days to determine if the 

affected source is in compliance with 

the MACT emission standard. For 

facilities that have roasters and 

autoclaves, the owner or operator can 

use the results of the previous 

compliance test for the autoclaves to 

determine the emissions for those 

process units to be used in the 

calculations of the emissions for the 

affected source. If the source is 

determined to be in compliance, the 

compliance test results may also be used 

to establish a new operating limit for 

mercury concentration (in accordance 

with paragraph (e) of this section). 

(iii) You must submit a monitoring 

plan that includes quality assurance and 

quality control (QA/QC) procedures 

sufficient to demonstrate the accuracy of 


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the CEMS to your permitting authority 

for approval 180 days prior to your 

initial compliance test. At a minimum, 

the QA/QC procedures must include 

daily calibrations and an annual 

accuracy test for the CEMS. 

(3) Continuously measure the mercury 

concentration in the final exhaust 

stream from each roaster using EPA 

Performance Specification 12B (40 CFR 

part 60 appendix B and Procedure 5 of 

appendix F). 

(i) You must continuously measure 

the mercury concentration in the roaster 

exhaust and maintain the average daily 

mercury concentration below the 

operating limit established in paragraph 

(a)(4) of this section. To determine the 

appropriate sampling duration, you 

must review the available data from 

previous stack tests to determine the 

upper 99th percentile of the range of 

mercury concentrations in the exit stack 

gas. Based on this upper end of 

expected concentrations, select an 

appropriate sampling duration that is 

likely to provide a valid sample and not 

result in breakthrough of the sampling 

tubes. If breakthrough of the sampling 

tubes occurs, you must re-sample within 

7 days using a shorter sampling 

duration. 

(ii) If the daily average mercury 

concentration is higher than the 

operating limit, the exceedance must be 

reported to the permit authority as a 

deviation and corrective actions must be 

implemented within 48 hours upon 

receipt of the sampling results. 

Moreover, within 96 hours of the 

exceedance, the owner or operator must 

measure the concentration again with 

PS 12B (40 CFR part 60, appendix B and 

Procedure 5 of appendix F), Method 30B 

or Method 29 (40 CFR part 60, appendix 

A–8), or ASTM D6784(incorporated by 

reference—see § 63.14) and demonstrate 

to the permit authority that the mercury 

concentration is no higher than the 

operating limit, or inform the permit 

authority that the limit continues to be 

exceeded. If the measured mercury 

concentration exceeds the operating 

limit for mercury concentration after 

these 96 hours, the exceedance must be 

reported as a deviation within 24 hours 

to the permitting authority and the 

owner or operator must conduct a full 

compliance test pursuant to 

§ 63.11646(a) for the roaster operations 

within 40 days to determine if the 

affected source is in compliance with 

the MACT emission standard. For 

facilities that have roasters and 

autoclaves, the owner or operator can 

use the results of the previous 

compliance test for the autoclaves to 

determine the emissions for those 

process units to be used in the 

calculations of the emissions for the 

affected source. If the source is 

determined to be in compliance, the 

compliance test results may also be used 

to establish a new operating limit for 

mercury concentration (in accordance 

with paragraph (e) of this section). 

(4) Use Equation (2) of this section to 

establish an upper operating limit for 

mercury concentration as determined by 

using the procedures in paragraphs 

(a)(1), (a)(2), or (a)(3) of this section 

concurrently while you are conducting 

your annual compliance performance 

stack tests according to the procedures 

in § 63.11646(a). 

Where: 

OLR = mercury concentration operating limit 

for the roaster (or roasters that share a 

common stack) (in micrograms per cubic 

meter); 

Ctest = average mercury concentration 

measured by the monitoring procedures 

(PS 12A or PS 12B or 30B) during the 

compliance performance stack test (in 

micrograms per cubic meter); 

EL = emission standard for ore pretreatment 

processes (in lb/million tons of ore); 

CT = compliance test results for ore 

pretreatment processes (in lb/million 

tons of ore). 

(5) For roasters that utilize calomelbased mercury control systems for 

emissions controls, you are not required 

to perform the monitoring for mercury 

emissions in paragraphs (a)(1), (a)(2), or 

(a)(3) of this section if you demonstrate 

to the satisfaction of your permitting 

authority that mercury emissions from 

the roaster are less than 10 pounds of 

mercury per million tons of ore 

throughput. If you make this 

demonstration, you must conduct the 

parametric monitoring as described 

below in paragraphs (b) and (c) of this 

section. 

(i) The initial demonstration must 

include three or more consecutive 

independent stack tests for mercury at 

least one month apart on the roaster 

exhaust stacks. Subsequent 

demonstrations may be based upon the 

single stack test required in paragraph 

(a) of section § 63.11646. The results of 

each of the tests must be less than 10 

pounds of mercury per million tons of 

ore. The testing must be performed 

according to the procedures in 

§ 63.11646(a)(1) through (a)(4) to 

determine mercury emissions in pounds 

per hour. 

(ii) Divide the mercury emission rate 

in pounds per hour by the ore 

throughput rate during the test 

expressed in millions of tons per hour 

to determine the emissions in pounds 

per million tons of ore. 

(b) For facilities with roasters and a 

calomel-based mercury control system 

that choose to monitor for mercury 

emissions using the procedures in 

paragraph (a)(1) of this section or that 

qualify for and choose to follow the 

requirements in paragraph (a)(5) of this 

section, you must establish operating 

parameter limits for scrubber liquor 

flow (or line pressure) and scrubber 

inlet gas temperature and monitor these 

parameters. You may establish your 

operating parameter limits from the 

initial compliance test, according to the 

manufacturer’s specifications, or based 

on limits established by the permitting 

authority. If you choose to establish 

your operating parameter limits from 

the initial compliance test, monitor the 

scrubber liquor flow (or line pressure) 

and scrubber inlet gas temperature 

during each run of your initial 

compliance test. The minimum 

operating limit for scrubber liquor flow 

rate (or line pressure) is either the 

lowest value during any run of the 

initial compliance test or 10 percent less 

than the average value measured during 

the compliance test, and your maximum 

scrubber inlet temperature limit is the 

highest temperature measured during 

any run of the initial compliance test or 

10 percent higher than the average value 

measured during the compliance test. 

You must monitor the scrubber liquor 

flow rate (or line pressure) and scrubber 

inlet gas temperature hourly and 

maintain the scrubber liquor flow (or 

line pressure) at or above the 

established operating parameter and 

maintain the inlet gas temperature 

below the established operating 

parameter limit. 

(c) For facilities with roasters and a 

calomel-based mercury control system 

that choose to monitor for mercury 

emissions using the procedures in 

paragraph (a)(1) of this section or that 

qualify for and follow the requirements 

in paragraph (a)(5) of this section, you 

must establish operating parameter 

ranges for mercuric ion and chloride ion 

concentrations or for oxidation 

reduction potential and pH using the 


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procedures in paragraph (c)(1) or (c)(2) 

of this section respectively. 

(1) Establish the mercuric ion 

concentration and chloride ion 

concentration ranges for each calomelbased mercury control system. The 

mercuric ion concentration and chloride 

ion concentration ranges for each 

calomel-based mercury control system 

must be based on the manufacturer’s 

specifications, or based on approval by 

your permitting authority. Measure the 

mercuric ion concentration and chloride 

ion concentrations at least once during 

each run of your initial compliance test. 

The measurements must be within the 

established concentration range for 

mercuric ion concentration and chloride 

ion concentration. Subsequently, you 

must sample at least once daily and 

maintain the mercuric ion concentration 

and chloride ion concentrations within 

their established range. 

(2) Establish the oxidation reduction 

potential and pH range for each 

calomel-based mercury control system. 

The oxidation reduction potential and 

pH range for each calomel-based 

mercury control system must be based 

on the manufacturer’s specifications, or 

based on approval by your permitting 

authority. Install monitoring equipment 

to continuously monitor the oxidation 

reduction potential and pH of the 

calomel-based mercury control system 

scrubber liquor. Measure the oxidation 

reduction potential and pH of the 

scrubber liquor during each run of your 

initial compliance test. The 

measurements must be within the 

established range for oxidation 

reduction potential and pH. 

Subsequently, you must monitor the 

oxidation reduction potential and pH of 

the scrubber liquor continuously and 

maintain it within the established 

operating range. 

(d) If you have an exceedance of a 

control device operating parameter 

range provided in paragraphs (b) or (c) 

of this section, you must take corrective 

action and bring the parameters back 

into the established parametric ranges. If 

the corrective actions taken following an 

exceedance do not result in the 

operating parameter value being 

returned within the established range 

within 48 hours, a mercury 

concentration measurement (with PS 

12B or PS 12A CEMS (40 CFR part 60, 

appendix B and Procedure 5 of 

appendix F), Method 30B or Method 29 

(40 CFR part 60, appendix A–8), or 

ASTM D6784 (incorporated by 

reference—see § 63.14)) must be made to 

determine if the operating limit for 

mercury concentration is being 

exceeded. The measurement must be 

performed and the mercury 

concentration determined within 48 

hours (after the initial 48 hours, or a 

total of 96 hours from the time the 

parameter range was exceeded). If the 

measured mercury concentration meets 

the operating limit for mercury 

concentration established under 

§ 63.11647(a)(4), the corrective actions 

are deemed successful, and the owner or 

operator can request the permit 

authority to establish a new limit or 

range for the parameter. If the measured 

mercury concentration exceeds the 

operating limit for mercury 

concentration after these 96 hours, the 

exceedance must be reported as a 

deviation within 24 hours to the 

permitting authority and the owner or 

operator must conduct a full compliance 

test pursuant to § 63.11646(a) for the 

roaster operations within 40 days to 

determine if the affected source is in 

compliance with the MACT emission 

standard. For facilities that have roasters 

and autoclaves, the owner or operator 

can use the results of the previous 

compliance test for the autoclaves to 

determine the emissions for those 

process units to be used in the 

calculations of the emissions for the 

affected source. If the source is 

determined to be in compliance with 

the MACT emission standard, the 

compliance test may also be used to 

establish a new operating limit for 

mercury concentration (see paragraph 

(e) of this section). 

(e) You may submit a request to your 

permitting authority for approval to 

change the operating limits established 

under paragraph (a)(4) of this section for 

the monitoring required in paragraph 

(a)(1),(a)(2), or (a)(3) of this section. In 

the request, you must demonstrate that 

the proposed change to the operating 

limit detects changes in levels of 

mercury emission control. An approved 

change to the operating limit under this 

paragraph only applies until a new 

operating limit is established during the 

next annual compliance test. 

(f) You must monitor each process 

unit at each new and existing affected 

source that uses a carbon adsorber to 

control mercury emissions using the 

procedures in paragraphs (f)(1) or (f)(2) 

of this section. A carbon adsorber may 

include a fixed carbon bed, carbon filter 

packs or modules, carbon columns, and 

other variations. 

(1) Continuously sample and analyze 

the exhaust stream from the carbon 

adsorber for mercury using Method 30B 

(40 CFR part 60, appendix A–8) for a 

duration of at least the minimum 

sampling time specified in Method 30B 

and up to one week that includes the 

period of the annual performance test. 

(i) Establish an upper operating limit 

for the process as determined using the 

mercury concentration measurements 

from the sorbent trap (Method 30B) as 

calculated from Equation (3) of this 

section. 

Where: 

OLC = mercury concentration operating limit 

for the carbon adsorber control device on 

the process as measured using the 

sorbent trap, (micrograms per cubic 

meter); 

Ctrap = average mercury concentration 

measured using the sorbent trap during 

the week that includes the compliance 

performance test, (micrograms per cubic 

meter); 

EL = emission standard for the affected 

sources (lb/ton of concentrate); 

CT = compliance test results for the affected 

sources (lb/ton of concentrate). 

(ii) Sample and analyze the exhaust 

stream from the carbon adsorber for 

mercury at least monthly using Method 

30B (40 CFR part 60, appendix A–8). 

When the mercury concentration 

reaches 75 percent of the operating 

limit, begin weekly sampling and 

analysis. When the mercury 

concentration reaches 90 percent of the 

operating limit, replace the carbon in 

the carbon adsorber within 30 days. If 

mercury concentration exceeds the 

operating limit, change the carbon in the 

carbon adsorber within 30 days and 

report the deviation to your permitting 

authority. 

(2) Conduct an initial sampling of the 

carbon in the carbon bed for mercury 90 

days after the replacement of the carbon. 

A representative sample must be 

collected from the inlet of the bed and 

the exit of the bed and analyzed using 

SW–846 Method 7471B (incorporated 

by reference—see § 63.14). The depth to 

which the sampler is inserted must be 

recorded. The design capacity is 

established by calculating the average 

carbon loading from the inlet and outlet 

measurements. Sampling and analysis 


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of the carbon bed for mercury must be 

performed quarterly thereafter. When 

the carbon loading reaches 50 percent of 

the design capacity of the carbon, 

monthly sampling must be performed 

until 90 percent of the carbon loading 

capacity is reached. The carbon must be 

removed and replaced with fresh carbon 

no later than 30 days after reaching 90 

percent of capacity. For carbon designs 

where there may be multiple carbon 

columns or beds, a representative 

sample may be collected from the first 

and last column or bed instead of the 

inlet or outlet. If the carbon loading 

exceeds the design capacity of the 

carbon, change the carbon within 30 

days and report the deviation to your 

permitting authority. 

(g) You must monitor gas stream 

temperature at the inlet to the carbon 

adsorber for each process unit (i.e., 

carbon kiln, melt furnace, etc.) equipped 

with a carbon adsorber. Establish a 

maximum value for the inlet 

temperature either during the annual 

performance test (required in 

§ 63.11646(a)), according to the 

manufacturer’s specifications, or as 

approved by your permitting authority. 

If you choose to establish the 

temperature operating limit during the 

performance test, establish the 

temperature operating limit based on 

either the highest reading during the test 

or at 10°F higher than the average 

temperature measured during the 

performance test. Monitor the inlet 

temperature once per shift. If an inlet 

temperature exceeds the temperature 

operating limit, you must take corrective 

actions to get the temperature back 

within the parameter operating limit 

within 48 hours. If the exceedance 

persists, within 144 hours of the 

exceedance, you must sample and 

analyze the exhaust stream from the 

carbon adsorber using Method 30B (40 

CFR part 60, appendix A–8) and 

compare to an operating limit 

(calculated pursuant to (f)(1)(i)) or you 

must conduct carbon sampling pursuant 

to (f)(2) of this section. If the 

concentration measured with Method 

30B is below 90 percent of the operating 

limit or the carbon sampling results are 

below 90 percent of the carbon loading 

capacity, you may set a new 

temperature operating limit 10°F above 

the previous operating limit or at an 

alternative level approved by your 

permit authority. If the concentration is 

above 90 percent of the operating limit 

or above 90 percent of the carbon 

loading capacity you must change the 

carbon in the bed within 30 days and 

report the event to your permitting 

authority, and reestablish an 

appropriate maximum temperature limit 

based on approval of your permit 

authority. 

(h) For each wet scrubber at each new 

and existing affected source not 

followed by a mercury control system, 

you must monitor the water flow rate (or 

line pressure) and pressure drop. 

Establish a minimum value as the 

operating limit for water flow rate (or 

line pressure) and pressure drop either 

during the performance test required in 

§ 63.11646(a), according to the 

manufacturer’s specifications, or as 

approved by your permitting authority. 

If you choose to establish the operating 

limit based on the results of the 

performance test, the new operating 

limit must be established based on 

either the lowest value during any test 

run or 10 percent less than the average 

value measured during the test. For wet 

scrubbers on an autoclave, establish the 

pressure drop range according to 

manufacturer’s specifications. You must 

monitor the water flow rate and 

pressure drop once per shift and take 

corrective action within 24 hours if any 

daily average is less than the operating 

limit. If the parameters are not in range 

within 72 hours, the owner or operator 

must report the deviation to the 

permitting authority and perform a 

compliance test for the process unit(s) 

controlled with the wet scrubber that 

has the parameter exceedance within 40 

days to determine if the affected source 

is in compliance with the MACT limit. 

For the other process units included in 

the affected source, the owner or 

operator can use the results of the 

previous compliance test to determine 

the emissions for those process units to 

be used in the calculations of the 

emissions for the affected source. 

(i) You may conduct additional 

compliance tests according to the 

procedures in § 63.11646 and reestablish the operating limits required 

in paragraphs (a) through (c) and (f) 

through (h) of this section at any time. 

You must submit a request to your 

permitting authority for approval to reestablish the operating limits. In the 

request, you must demonstrate that the 

proposed change to the operating limit 

detects changes in levels of mercury 

emission control. An approved change 

to the operating limit under this 

paragraph only applies until a new 

operating limit is established during the 

next annual compliance test. 

§ 63.11648 What are my notification, 

reporting, and recordkeeping 

requirements? 

(a) You must submit the Initial 

Notification required by § 63.9(b)(2) no 

later than 120 calendar days after the 

date of publication of the final rule in 

the Federal Register or within 120 days 

after the source becomes subject to the 

standard. The Initial Notification must 

include the information specified in 

§ 63.9(b)(2)(i) through (b)(2)(iv). 

(b) You must submit an initial 

Notification of Compliance Status as 

required by § 63.9(h). 

(c) If a deviation occurs during a 

semiannual reporting period, you must 

submit a deviation report to your 

permitting authority according to the 

requirements in paragraphs (c)(1) and 

(2) of this section. 

(1) The first reporting period covers 

the period beginning on the compliance 

date specified in § 63.11641 and ending 

on June 30 or December 31, whichever 

date comes first after your compliance 

date. Each subsequent reporting period 

covers the semiannual period from 

January 1 through June 30 or from July 

1 through December 31. Your deviation 

report must be postmarked or delivered 

no later than July 31 or January 31, 

whichever date comes first after the end 

of the semiannual reporting period. 

(2) A deviation report must include 

the information in paragraphs (c)(2)(i) 

through (c)(2)(iv) of this section. 

(i) Company name and address. 

(ii) Statement by a responsible 

official, with the official’s name, title, 

and signature, certifying the truth, 

accuracy and completeness of the 

content of the report. 

(iii) Date of the report and beginning 

and ending dates of the reporting 

period. 

(iv) Identification of the affected 

source, the pollutant being monitored, 

applicable requirement, description of 

deviation, and corrective action taken. 

(d) If you had a malfunction during 

the reporting period, the compliance 

report required in § 63.11648(b) must 

include the number, duration, and a 

brief description for each type of 

malfunction which occurred during the 

reporting period and which caused or 

may have caused any applicable 

emission limitation to be exceeded. The 

report must also include a description of 

actions taken by an owner or operator 

during a malfunction of an affected 

source to minimize emissions in 

accordance with § 63.11646(b), 

including actions taken to correct a 

malfunction. 

(e) You must keep the records 

specified in paragraphs (e)(1) through 

(e)(3) of this section. The form and 

maintenance of records must be 

consistent with the requirements in 

section 63.10(b)(1) of the General 

Provisions. 

(1) As required in § 63.10(b)(2)(xiv), 

you must keep a copy of each 


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notification that you submitted to 

comply with this subpart and all 

documentation supporting any Initial 

Notification, Notification of Compliance 

Status, and semiannual compliance 

certifications that you submitted. 

(2) You must keep the records of all 

performance tests, measurements, 

monitoring data, and corrective actions 

required by §§ 63.11646 and 63.11647, 

and the information identified in 

paragraphs (c)(2)(i) through (c)(2)(vi) of 

this section for each corrective action 

required by § 63.11647. 

(i) The date, place, and time of the 

monitoring event requiring corrective 

action; 

(ii) Technique or method used for 

monitoring; 

(iv) Operating conditions during the 

activity; 

(v) Results, including the date, time, 

and duration of the period from the time 

the monitoring indicated a problem to 

the time that monitoring indicated 

proper operation; and 

(vi) Maintenance or corrective action 

taken (if applicable). 

(3) You must keep records of 

operating hours for each process as 

required by § 63.11646(a)(5) and records 

of the monthly quantity of ore and 

concentrate processed or produced as 

required by § 63.11646(a)(10). 

(f) Your records must be in a form 

suitable and readily available for 

expeditious review, according to 

§ 63.10(b)(1). As specified in 

§ 63.10(b)(1), you must keep each record 

for 5 years following the date of each 

recorded action. You must keep each 

record onsite for at least 2 years after the 

date of each recorded action according 

to § 63.10(b)(1). You may keep the 

records offsite for the remaining 3 years. 

(g) After December 31, 2011, within 

60 days after the date of completing 

each performance evaluation conducted 

to demonstrate compliance with this 

subpart, the owner or operator of the 

affected facility must submit the test 

data to EPA by entering the data 

electronically into EPA’s WebFIRE data 

base through EPA’s Central Data 

Exchange. The owner or operator of an 

affected facility shall enter the test data 

into EPA’s data base using the 

Electronic Reporting Tool or other 

compatible electronic spreadsheet. Only 

performance evaluation data collected 

using methods compatible with ERT are 

subject to this requirement to be 

submitted electronically into EPA’s 

WebFIRE database. 

Other Requirements and Information 

§ 63.11650 What General Provisions apply 

to this subpart? 

Table 1 to this subpart shows which 

parts of the General Provisions in 

§§ 63.1 through 63.16 apply to you. 

§ 63.11651 What definitions apply to this 

subpart? 

Terms used in this subpart are 

defined in the Clean Air Act, in § 63.2, 

and in this section as follows: 

Autoclave means a pressure oxidation 

vessel that is used to treat gold ores 

(primarily sulfide refractory ore) and 

involves pumping a slurry of milled ore 

into the vessel which is highly 

pressurized with oxygen and heated to 

temperatures of approximately 350° to 

430° F. 

Calomel-based mercury control 

system means a mercury emissions 

control system that uses scrubbers to 

remove mercury from the gas stream of 

a roaster or combination of roasters by 

complexing the mercury from the gas 

stream with mercuric chloride to form 

mercurous chloride (calomel). These 

scrubbers are also referred to as 

‘‘mercury scrubbers.’’ 

Carbon adsorber means a control 

device consisting of a single fixed 

carbon bed, multiple carbon beds or 

columns, carbon filter packs or 

modules, and other variations that uses 

activated carbon to remove pollutants 

from a gas stream. 

Carbon kiln means a kiln or furnace 

where carbon is regenerated by heating, 

usually in the presence of steam, after 

the gold has been stripped from the 

carbon. 

Carbon processes with mercury retorts 

means the affected source that includes 

carbon kilns, preg tanks, electrowinning 

cells, mercury retorts, and melt furnaces 

at gold mine ore processing and 

production facilities that use activated 

carbon, or resins that can be used as a 

substitute for activated carbon, to 

recover (adsorb) gold from the pregnant 

cyanide solution. 

Carbon processes without mercury 

retorts means the affected source that 

includes carbon kilns, preg tanks, 

electrowinning cells, and melt furnaces, 

but has no retorts, at gold mine ore 

processing and production facilities that 

use activated carbon, or resins that can 

be used as a substitute for activated 

carbon, to recover (adsorb) gold from the 

pregnant cyanide solution. 

Concentrate means the sludge-like 

material that is loaded with gold along 

with various other metals (such as 

silver, copper, and mercury) and various 

other substances, that is produced by 

electrowinning, the Merrill-Crowe 

process, flotation and gravity separation 

processes. Concentrate is measured as 

the input to mercury retorts, or for 

facilities without mercury retorts, as the 

input to melt furnaces before any drying 

takes place. For facilities without 

mercury retorts or melt furnaces, 

concentrate is measured as the quantity 

shipped. 

Deviation means any instance where 

an affected source subject to this 

subpart, or an owner or operator of such 

a source: 

(1) Fails to meet any requirement or 

obligation established by this subpart, 

including but not limited to any 

emissions limitation or work practice 

standard; 

(2) Fails to meet any term or condition 

that is adopted to implement an 

applicable requirement in this subpart 

and that is included in the operating 

permit for any affected source required 

to obtain such a permit; or 

(3) Exceeds any operating limit 

established under this subpart. 

Electrowinning means a process that 

uses induced voltage on anode and 

cathode plates to remove metals from 

the continuous flow of solution, where 

the gold in solution is plated onto the 

cathode. Steel wool is typically used as 

the plating surface. 

Electrowinning Cells means a tank in 

which the electrowinning takes place. 

Gold mine ore processing and 

production facility means any industrial 

facility engaged in the processing of 

gold mine ore that uses any of the 

following processes: Roasting 

operations, autoclaves, carbon kilns, 

preg tanks, electrowinning, mercury 

retorts, or melt furnaces. Laboratories 

(see CAA section 112(c)(7)), individual 

prospectors, and very small pilot scale 

mining operations that processes or 

produces less than 100 pounds of 

concentrate per year are not a gold mine 

ore processing and production facility. 

A facility that produces primarily 

metals other than gold, such as copper, 

lead, zinc, or nickel (where these metals 

other than gold comprise 95 percent or 

more of the total metal production) that 

may also recover some gold as a 

byproduct is not a gold mine ore 

processing and production facility. 

Those facilities whereby 95 percent or 

more of total mass of metals produced 

are metals other than gold, whether final 

metal production is onsite or offsite, are 

not part of the gold mine ore processing 

and production source category. 

Melt furnace means a furnace 

(typically a crucible furnace) that is 

used for smelting the gold-bearing 

material recovered from mercury 

retorting, or the gold-bearing material 

from electrowinning, the Merrill-Crowe 


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process, or other processes for facilities 

without mercury retorts. 

Mercury retort means a vessel that is 

operated under a partial vacuum at 

approximately 1,100 ° to 1,300 °F to 

remove mercury and moisture from the 

gold bearing sludge material that is 

recovered from electrowinning, the 

Merrill-Crowe process, or other 

processes. Mercury retorts are usually 

equipped with condensers that recover 

liquid mercury during the processing. 

Merrill-Crowe process means a 

precipitation technique using zinc oxide 

for removing gold from a cyanide 

solution. Zinc dust is added to the 

solution, and gold is precipitated to 

produce a concentrate. 

Non-carbon concentrate processes 

means the affected source that includes 

mercury retorts and melt furnaces at 

gold mine ore processing and 

production facilities that use the 

Merrill-Crowe process or other 

processes and do not use carbon (or 

resins that substitute for carbon) to 

recover (adsorb) gold from the pregnant 

cyanide solution. 

Ore dry grinding means a process in 

which the gold ore is ground and heated 

(dried) prior to additional preheating or 

prior to entering the roaster. 

Ore preheating means a process in 

which ground gold ore is preheated 

prior to entering the roaster. 

Ore pretreatment processes means the 

affected source that includes roasting 

operations and autoclaves that are used 

to pre-treat gold mine ore at gold mine 

ore processing and production facilities 

prior to the cyanide leaching process. 

Pregnant solution tank (or preg tank) 

means a storage tank for pregnant 

solution, which is the cyanide solution 

that contains gold-cyanide complexes 

that is generated from leaching gold ore 

with cyanide solution. 

Pregnant cyanide solution means the 

cyanide solution that contains goldcyanide complexes that are generated 

from leaching gold ore with a dilute 

cyanide solution. 

Quenching means a process in which 

the hot calcined ore is cooled and 

quenched with water after it leaves the 

roaster. 

Roasting operation means a process 

that uses an industrial furnace in which 

milled ore is combusted across a 

fluidized bed to oxidize and remove 

organic carbon and sulfide mineral 

grains in refractory gold ore. The 

emissions points of the roasting 

operation subject to this subpart include 

ore dry grinding, ore preheating, the 

roaster stack, and quenching. 

§ 63.11652 Who implements and enforces 

this subpart? 

(a) This subpart can be implemented 

and enforced by the U.S. EPA or a 

delegated authority, such as your state, 

local, or tribal agency. If the U.S. EPA 

Administrator has delegated authority to 

your state, local, or tribal agency, then 

that agency has the authority to 

implement and enforce this subpart. 

You should contact your U.S. EPA 

Regional Office to find out if this 

subpart is delegated to your state, local, 

or tribal agency. 

(b) In delegating implementation and 

enforcement authority of this subpart to 

a state, local, or tribal agency under 40 

CFR part 63, subpart E, the authorities 

contained in paragraph (c) of this 

section are retained by the 

Administrator of the U.S. EPA and are 

not transferred to the state, local, or 

tribal agency. 

(c) The authorities that will not be 

delegated to state, local, or tribal 

agencies are listed in paragraphs (c)(1) 

through (4) of this section. 

(1) Approval of alternatives to the 

applicability requirements in 

§ 63.11640, the compliance date 

requirements in § 63.11641, and the 

applicable standards in § 63.11645. 

(2) Approval of an alternative 

nonopacity emissions standard under 

§ 63.6(g). 

(3) Approval of a major change to a 

test method under § 63.7(e)(2)(ii) and (f). 

A ‘‘major change to test method’’ is 

defined in § 63.90(a). 

(4) Approval of a major change to 

monitoring under § 63.8(f). A ‘‘major 

change to monitoring’’ is defined in 

§ 63.90(a). 

(5) Approval of a waiver of 

recordkeeping or reporting requirements 

under § 63.10(f), or another major 

change to recordkeeping/reporting. A 

‘‘major change to recordkeeping/ 

reporting’’ is defined in § 63.90(a). 

§ 63.11653 [Reserved] 

Tables to Subpart EEEEEEE of Part 63 

TABLE 1 TO SUBPART EEEEEEE OF PART 63—APPLICABILITY OF GENERAL PROVISIONS TO SUBPART EEEEEE 

[As stated in § 63.11650, you must comply with the applicable General Provisions requirements according to the following table] 

Citation Subject Applies to 

subpart EEEEEEE Explanation 

§ 63.1(a)(1), (a)(2), (a)(3), (a)(4), 

(a)(6), (a)(10)–(a)(12), (b)(1), (b)(3), 

(c)(1), (c)(2), (c)(5), (e).

Applicability .......................................... Yes.

§ 63.1(a)(5), (a)(7)–(a)(9), (b)(2), 

(c)(3), (c)(4), (d).

Reserved ............................................. No.

§ 63.2 ................................................... Definitions ............................................ Yes.

§ 63.3 ................................................... Units and Abbreviations ...................... Yes.

§ 63.4 ................................................... Prohibited Activities and Circumvention.Yes.

§ 63.5 ................................................... Preconstruction Review and Notification Requirements.Yes.

§ 63.6(a), (b)(1)–(b)(5), (b)(7), (c)(1), 

(c)(2), (c)(5), (e)(1)(iii), (f)(2), (f)(3), 

(g), (i), (j).

Compliance with Standards and Maintenance Requirements.Yes.

§ 63.6(e)(1)(i) and (ii), (e)(3), and (f)(1) Startup, Shutdown and Malfunction 

Requirements (SSM).

No .............................. Subpart EEEEEEE standards apply at 

all times. 

§ 63.6(h)(1), (h)(2), (h)(4),(h)(5)(i), (ii), 

(iii) and (v), (h)(6)–(h)(9).

Compliance with Opacity and Visible 

Emission Limits.

No .............................. Subpart EEEEEEE does not contain 

opacity or visible emission limits. 

§ 63.6(b)(6), (c)(3), (c)(4), (d), (e)(2), 

(e)(3)(ii), (h)(3), (h)(5)(iv).

Reserved ............................................. No.

§ 63.7, except (e)(1) ............................. Applicability and Performance Test 

Dates.

Yes.

§ 63.7(e)(1) ........................................... Performance Testing Requirements 

Related to SSM.

No.


jlentini on DSKJ8SOYB1PROD with RULES2
Federal Register / Vol. 76, No. 33 / Thursday, February 17, 2011 / Rules and Regulations 9489 

TABLE 1 TO SUBPART EEEEEEE OF PART 63—APPLICABILITY OF GENERAL PROVISIONS TO SUBPART EEEEEE— 

Continued 

[As stated in § 63.11650, you must comply with the applicable General Provisions requirements according to the following table] 

Citation Subject Applies to 

subpart EEEEEEE Explanation 

§ 63.8(a)(1), (b)(1), (f)(1)–(5), (g) ......... Monitoring Requirements .................... Yes.

§ 63.8(a)(2), (a)(4), (b)(2)–(3), (c), (d), 

(e), (f)(6), (g).

Continuous Monitoring Systems ......... Yes ............................ Except cross references to SSM requirements in § 63.6(e)(1) and (3) 

do not apply. 

§ 63.8(a)(3) ........................................... [Reserved] ........................................... No.

§ 63.9(a), (b)(1), (b)(2)(i)–(v), (b)(4), 

(b)(5), (c), (d), (e), (g), (h)(1)–(h)(3), 

(h)(5), (h)(6), (i), (j).

Notification Requirements ................... Yes.

§ 63.9(f) ................................................ .............................................................. No.

§ 63.9(b)(3), (h)(4) ................................ Reserved ............................................. No.

§ 63.10(a), (b)(1), (b)(2)(vi)–(xiv), 

(b)(3), (c), (d)(1)–(4), (e), (f).

Recordkeeping and Reporting Requirements.Yes.

§ 63.10(b)(2)(i)–(v), (d)(5) .................... Recordkeeping/Reporting Associated 

with SSM.

No.

§ 63.10(c)(2)–(c)(4), (c)(9) ................... Reserved ............................................. No.

§ 63.11 ................................................. Control Device Requirements ............. No.

§ 63.12 ................................................. State Authority and Delegations ......... Yes.

§§ 63.13–63.16 .................................... Addresses, Incorporation by Reference, Availability of Information, 

Performance Track Provisions.

Yes.

[FR Doc. 2011–2608 Filed 2–16–11; 8:45 am] 

BILLING CODE 6560–50–P 


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