2013-31267. National Emissions Standards for Hazardous Air Pollutants from Secondary Lead Smelting

AGENCY:

Environmental Protection Agency (EPA).

ACTION:

Direct final rule.

SUMMARY:

The Environmental Protection Agency (EPA) is taking direct final action to promulgate amendments to a final rule that revised national emission standards for hazardous air pollutants for existing and new secondary lead smelters. The final rule was published on January 5, 2012. This direct final action amends certain regulatory text to clarify compliance dates. Additionally, we are making amendments to clarify certain provisions in the 2012 final rule related to monitoring of negative pressure in total enclosures. This action also corrects typographical errors in a table listing congeners of dioxins and furans and the testing requirements for total hydrocarbons.

DATES:

This rule is effective on March 4, 2014 without further notice, unless the EPA receives adverse comment by February 3, 2014. If we receive adverse comment, we will publish a timely withdrawal in the Federal Register informing the public that this rule, or relevant provisions of this rule, will not take effect.

ADDRESSES:

You may submit comments, identified by Docket ID Number EPA-HQ-OAR-2011-0344, by one of the following methods:

• http://www.regulations.gov: Follow the online instructions for submitting comments.
• Email: [e-mail], Attention Docket ID Number EPA-HQ-OAR-2011-0344.
• Fax: [phone], Attention Docket ID Number EPA-HQ-OAR-2011-0344.
• Mail: U.S. Postal Service, send comments to: EPA Docket Center, EPA West (Air Docket), Attention Docket ID Number EPA-HQ-OAR-2011-0344, U.S. Environmental Protection Agency, Mailcode: 2822T, 1200 Pennsylvania Ave., NW., Washington, DC 20460. Please include a total of two copies.
• Hand Delivery: U.S. Environmental Protection Agency, EPA West (Air Docket), Room 3334, 1301 Constitution Ave., NW., Washington, DC 20004, Attention Docket ID Number EPA-HQ-OAR-2011-0344. Such deliveries are only accepted during the Docket's normal hours of operation, and special arrangements should be made for deliveries of boxed information.

Instructions. Direct your comments to Docket ID Number EPA-HQ-OAR-2011-0344. The EPA's policy is that all comments received will be included in the public docket without change and may be made available online at http://www.regulations.gov,, including any personal information provided, unless the comment includes information claimed to be confidential business information (CBI) or other information whose disclosure is restricted by statute. Do not submit information that you consider to be CBI or otherwise protected through http://www.regulations.gov or email. The http://www.regulations.gov Web site is an “anonymous access” system, which means the EPA will not know your identity or contact information unless you provide it in the body of your comment. If you send an email comment directly to the EPA without going through http://www.regulations.gov,, your email address will be automatically captured and included as part of the comment that is placed in the public docket and made available on the Internet. If you submit an electronic comment, the EPA recommends that you include your name and other contact information in the body of your comment and with any disk or CD-ROM you submit. If the EPA cannot read your comment due to technical difficulties and cannot contact you for clarification, the EPA may not be able to consider your comment. Electronic files should not include special characters, any form of encryption, and be free of any defects or viruses. For additional information about the EPA's public docket, visit the EPA Docket Center homepage at http://www.epa.gov/​dockets.

Docket. The EPA has established a docket for this rulemaking under Docket ID Number EPA-HQ-OAR-2011-0344. All documents in the docket are listed in the http://www.regulations.gov index. Although listed in the index, some information is not publicly available, e.g., CBI or other information whose disclosure is restricted by statute. Certain other material, such as copyrighted material, is not placed on the Internet, and will be publicly available only in hard copy. Publicly available docket materials are available either electronically in http://www.regulations.gov or in hard copy at the EPA Docket Center, EPA West, Room 3334, 1301 Constitution Ave. NW., Washington, DC. The Public Reading Room is open from 8:30 a.m. to 4:30 p.m., Monday through Friday, excluding legal holidays. The telephone number for the Public Reading Room is [phone], and the telephone number for the EPA Docket Center is [phone].

FOR FURTHER INFORMATION CONTACT:

For questions about this action, contact Mr. Nathan Topham, Metals and Inorganic Chemicals Group, Sector Policies and Programs Division (D243-02), U.S. Environmental Protection Agency, Research Triangle Park, NC 27711; telephone number: [phone]; fax number: [phone]; and email address: [e-mail].

SUPPLEMENTARY INFORMATION:

Organization of this Document. The following outline is provided to aid in locating information in the preamble.

I. What is the background for the amendments?

II. What are the changes to the final rule?

III. Statutory and Executive Order Reviews

A. Executive Order 12866: Regulatory Planning and Review, and Executive Order 13563: Improving Regulation and Regulatory Review

B. Paperwork Reduction Act

C. Regulatory Flexibility Act

D. Unfunded Mandates Reform Act

E. Executive Order 13132: Federalism

F. Executive Order 13175: Consultation and Coordination With Indian Tribal Governments

G. Executive Order 13045: Protection of Children From Environmental Health Risks and Safety Risks

H. Executive Order 13211: Actions Concerning Regulations That Significantly Affect Energy Supply, Distribution, or Use

I. National Technology Transfer and Advancement Act

J. Executive Order 12898: Federal Actions To Address Environmental Justice in Minority Populations and Low-Income Populations

K. Congressional Review Act

I. What is the background for the amendments?

On January 5, 2012 (77 FR 556), EPA published final amendments to the National Emissions Standards for Hazardous Air Pollutants (NESHAP) From Secondary Lead Smelting. The EPA has subsequently determined, following discussions with affected parties, that the final rule warrants clarification in four areas.

The EPA inadvertently removed from 40 CFR part 63, subpart X the requirement for facilities constructed or reconstructed on or before May 19, 2011, to comply with the previous version of the NESHAP between promulgation of the January 5, 2012, amendments and the subsequent compliance date for existing sources, which is January 6, 2014. Since existing sources remain subject to the pre-existing standards until the compliance date for the January 2012 standards, the EPA is amending the rule to restore the deleted language.

The EPA received petitions for reconsideration of the final rule from the secondary lead smelting industry. One issue raised in the petitions relates to the table of dioxin and furan congeners contained in the regulatory text (Table 3 to Subpart X of Part 63—Toxic Equivalency Factors). This table included incorrect values for some dioxin toxic equivalency factors (TEF) and omitted some congeners. The EPA intended to use the 2005 World Health Organization (WHO) TEF in Table 3 to subpart X of part 63. See 76 FR 29051, “The TEQ emissions will be calculated using the toxic equivalency factors (TEF) outlined by the World Health Organization (WHO) in 2005 (available at Web site: http://www.epa.gov/​raf/​hhtefguidance/​).”

Industry petitioners expressed concern that the agency changed one aspect of the emission standard for total hydrocarbons (THC) between proposing and finalizing the risk and technology review amendments for secondary lead smelters. In the 2011 proposed rule, the total hydrocarbon standard for furnace charging process fugitive emissions that are not combined with furnace process emissions did not require correction to 4-percent carbon dioxide (CO₂). See the Federal Register at 76 FR 29072, May 19, 2011. In the 2012 final rule, this standard inadvertently included correction to 4-percent CO₂. See the Federal Register at 77 FR 582, January 5, 2012.

Finally, petitioners asked the EPA to clarify several monitoring provisions for total enclosures. Industry requested flexibility in defining the term “windward wall” when a total enclosure is not impacted by ambient wind. The regulatory text was unclear where to place monitors when ambient wind does not affect the total enclosure. Petitioners requested clarification in how to monitor enclosures that are divided into multiple areas all under negative pressure. Petitioners also asked the EPA to clarify that data from differential pressure monitors should be used to calculate 15-minute averages. Petitioners also stated that the EPA should clarify the meaning of “accuracy” in 40 CFR 63.548(k)(3).

The EPA is issuing the amendments as a direct final rule, without a prior proposal, because we view the revisions as noncontroversial and anticipate no adverse comment. The EPA never intended to remove the pre-January 2012 NESHAP from the Code of Federal Regulations (CFR), and no commenters suggested such an action. Additionally, the errors in Table 3 to subpart X of part 63 and the THC correction for furnace charging process fugitive emissions are simply typographical errors. The differential pressure monitoring clarifications do not alter the impacts of the 2012 final rule and simply clarify requirements from that rulemaking. The monitoring clarifications include the following: Clarifying the definition of windward wall; clarifying how to monitor pressure in situations where smaller enclosures are located within larger full enclosures; clarifying the averaging time for the monitoring; and clarifying the calibration requirements for the monitoring equipment. However, in the Proposed Rules section of this Federal Register issue, the EPA is also publishing a separate document that will serve as the proposal to amend the Secondary Lead Smelting NESHAP with the same amendments contained in this direct final action if significant adverse comments are submitted. The EPA will not institute a second comment period on this action. Any parties interested in commenting must do so at this time. The EPA will address all public comments in any subsequent final rule based on the proposed rule. We will address other issues for which we have received requests for reconsideration in a separate proposal that will be published at a later date.

II. What are the changes to the final rule?

We are clarifying compliance requirements for existing sources for the period beginning January 5, 2012, and ending on the compliance date for existing sources established in the final rule published in the Federal Register at 77 FR 584, January 5, 2012. See 40 CFR 63.546(a). When the final rule was published in the Federal Register, the subpart was reprinted in its entirety to aid the public in locating and understanding the requirements for secondary lead smelters. This inadvertently removed the earlier version of 40 CFR part 63, subpart X from the CFR. This direct final rule clarifies that secondary lead smelters that commenced construction or reconstruction before May 19, 2011 (i.e., all sources existing as of that time, which includes sources classified as both existing and new under the previous rule), are still subject to the requirements of subpart X for new and existing sources that were effective prior to the January 5, 2012, amendments, and remain subject to those provisions until the compliance date for the January 5, 2012, amendments. Specifically, sources that were classified as new under the previous rule, (i.e., those which commenced construction after June 9, 1994) are subject to the previous rule's new source standards (codified at former 40 CFR 63.543 through 63.545). Existing sources under the previous rule are subject to the previous rule's existing source standards (codified at former 40 CFR 63.543 through 63.545). We have added paragraph (c) to 40 CFR 63.546 to correct this inadvertent error.

The EPA is also correcting typographical errors in Table 3 to subpart X of part 63. The table did not include all of the 2005 WHO TEF and had incorrect TEF values for some of the congeners included in the table. The EPA is not changing the emission standards for dioxins and furans from the 2012 final rule or using different congeners than we intended to include in the 2011 proposed rule or 2012 final rule. See 76 FR 29051, “The TEQ emissions will be calculated using the toxic equivalency factors (TEF) outlined by the World Health Organization (WHO) in 2005 (available at Web site: http://www.epa.gov/​raf/​hhtefguidance/​)”.

We are removing the CO₂ correction requirement that we inadvertently added to 40 CFR 63.543(f) in the final rule. We did not intend to make this change between the proposed and final rules, did not receive comments on this issue, and did not discuss it in the preamble to the final rule or supporting documents. The hoods that capture furnace charging process fugitive emissions draw a large amount of excess ambient air with very low concentrations of CO₂. Measured concentrations of THC would be inappropriately multiplied by 10 if CO₂ corrections were required for these sources. This amendment will not change the impacts of the 2012 final rule since we did not intend to make this change between the proposed and final rules.

We are also clarifying five parts of the rule establishing differential pressure monitoring requirements for negative pressure enclosures. These corrections are intended to clarify existing requirements and do not change the impacts of the final rule.

1. Placement of Pressure Monitors for Total Enclosures Inside Larger Structures

Industry petitioners requested that the EPA clarify how differential pressure monitors should be arranged within total enclosures when those enclosures exist within or as part of a larger structure. The EPA granted reconsideration in order to provide needed clarifications. In the 2012 final rule, differential pressure monitors are required on walls within a total enclosure to ensure negative pressure is maintained within the enclosure. See 40 CFR 63.548(k). The EPA included definitions for “windward” and “leeward” walls to determine which walls within a total enclosure should have differential pressure monitors. Windward and leeward walls were defined using prevailing ambient wind directions. See 40 CFR 63.542. Industry petitioners stated that some total enclosures are within larger structures that shield the total enclosure from impacts of ambient wind. Furthermore, we have determined there are significant technical difficulties associated with monitoring negative pressure in areas that open into other areas that are also under negative pressure. Therefore, as explained in more detail under item number 5 below, in situations where smaller enclosures are contained within larger total enclosed structures, we are clarifying that facilities only need to monitor pressure differential for the larger total enclosure. Furthermore, in this action, we are clarifying that in such situations, owners or operators may choose which wall to define as the “windward wall” for placing differential pressure monitors. We are also adding regulatory text that allows a permit authority to approve an alternative location for the third monitor placed between the windward and leeward wall monitors. Industry commenters stated that irregularly shaped enclosures would make it difficult to determine where to place the monitor under the current requirements. This clarification will not adversely affect the quality or frequency of data collection from differential pressure monitors.

2. Averaging Time for Differential Pressure Monitoring Data

The 2012 final rule for secondary lead smelters requires differential pressure monitors in order to demonstrate continuous compliance with the requirements of 40 CFR 63.544(c)(1). Industry petitioners stated that the 2012 final rule creates uncertainty about how to handle data collected from differential pressure monitors. The 2012 final rule did not explicitly state how to use the data collected from the monitors, although the rule did incorporate 40 CFR 63.10(b)(2)(vii), which requires records of 15-minute averages of data collected from continuous monitoring systems. In this action, we are clarifying that the data collected from the continuous pressure monitors must be used to calculate 15-minute averages that are used to demonstrate compliance. This amendment does not alter the impacts of the 2012 final rule. Rather, it simply clarifies the existing requirements already included in the 2012 rule by explicitly stating the requirements previously referenced in the general provisions.

3. Differential Pressure Monitoring Device Accuracy

The 2012 final rule included a requirement for differential pressure monitors with “minimum accuracy of plus or minus 0.001 millimeters of mercury (0.0005 inches of water).” See 40 CFR 63.548(k)(3). Industry has expressed concerns that there are not monitors available with certified accuracy at the levels prescribed in the 2012 final rule. We included the accuracy requirement in the 2012 final rule to ensure that the differential pressure monitors display and record data with sufficient sensitivity to demonstrate compliance with the standard. Our goal was to require monitors that display and record data with sufficient significant figures, rather than a specific certified accuracy level. We are clarifying this requirement in the regulatory text. We are changing the sensitivity requirement from 0.0005 inches of water to 0.001 inches of water. Industry commenters noted difficulty finding monitors with sufficient sensitivity to meet the original requirement. Monitors capable of recording data in increments of 0.001 inches of water are sufficient to determine compliance with the standard. This clarification will not have any impact on the cost or environmental impacts of the 2012 final rule or impact the quality or frequency of differential pressure data collection.

4. Calibration Schedule for Differential Pressure Monitors

We are amending the regulatory text to simplify requirements for calibrating differential pressure monitors. See 40 CFR 63.548(k)(5). We have changed the regulatory text to require calibration per manufacturer's specifications rather than on a prescribed schedule. It has come to our attention that some manufacturers of differential pressure monitors do not require or recommend calibration as frequently as once per year. The amended requirements will ensure that monitors are calibrated properly without requiring adjustments more frequently than manufacturers recommend.

5. Monitoring Enclosures That Only Open Into Other Enclosures

We are adding regulatory text to address how negative pressure within total enclosures must be monitored when those enclosures only open into other totally enclosed process areas. If a source, or group of sources, is in a totally enclosed part of a building that only opens into other areas that are also totally enclosed under negative pressure, the source only needs to monitor differential pressure on the outermost walls of the enclosure that opens to areas that are not enclosed under negative pressure. This change ensures that facilities maintain negative pressure in structures housing process areas without unnecessary monitoring requirements. It is redundant to monitor negative pressure in process areas that open into other totally enclosed process areas under negative pressure. Additionally, it has come to our attention that there are technical difficulties associated with monitoring negative pressure in areas that open into other areas also under negative pressure. The modified regulatory text will ensure that monitors are able to function properly by specifying that monitors are not to be placed on walls with no exposure to ambient pressure on either side of the wall.

We have not made any other changes to the final rule in this direct final action. We note that we are not re-proposing, reconsidering, or in any other way re-opening any other aspects of the final rule for comment through this direct final action.

III. Statutory and Executive Order Reviews

A. Executive Order 12866: Regulatory Planning and Review, and Executive Order 13563: Improving Regulation and Regulatory Review

This action is not a “significant regulatory action” under the terms of Executive Order (EO) 12866 (58 FR 51735, October 4, 1993), and is, therefore, not subject to review under Executive Order 12866 and 13563 (76 FR 3821, January 21, 2011).

B. Paperwork Reduction Act

This action does not impose any new information collection burden. This action adds clarifications and corrections to the final standards. However, OMB has previously approved the information collection requirements contained in the existing regulation (40 CFR part 63, subpart X) under the provisions of the Paperwork Reduction Act, 44 U.S.C. 3501, et seq., and has assigned OMB control number 2060-0296. The OMB control numbers for EPA's regulations in 40 CFR are listed in 40 CFR part 9.

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 the rule will not have a significant economic impact on a substantial number of small entities. Small entities include small businesses, small organizations, and small governmental jurisdictions.

For purposes of assessing the impact of this rule on small entities, small entity is defined as: (1) A small business as defined by Small Business Administration (SBA) regulations at 13 CFR 121.201; (2) a small governmental jurisdiction that is a government of a city, county, town, school district, or special district with a population of less than 50,000; and (3) a small organization that is any not-for-profit enterprise which is independently owned and operated and is not dominant in its field.

After considering the economic impact of this direct 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 will not impose any requirements on small entities because it does not add any additional regulatory requirements and only clarifies the existing compliance requirements.

D. Unfunded Mandates Reform Act

This action contains no Federal mandates under the provisions of Title II of the Unfunded Mandates Reform Act of 1995 (UMRA), 2 U.S.C. 1531-1538 for State, local, or tribal governments or the private sector. The action imposes no enforceable duties on any state, local or tribal governments or the private sector. Therefore, this action is not subject to the requirements of sections 202 or 205 of the UMRA.

This action 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 because it contains no requirements that apply to such governments nor does it impose 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 direct final rule primarily affects private industry, and does not impose significant economic costs on state or local governments. Thus, Executive Order 13132 does not apply to this action.

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). It will not have substantial direct effect on tribal governments, on the relationship between the federal government and Indian tribes or on the distribution of power and responsibilities between the federal government and Indian tribes as specified in Executive Order 13175. Thus, Executive Order 13175 does not apply to this action.

G. Executive Order 13045: Protection of Children From Environmental Health Risks and Safety Risks

The EPA interprets Executive Order 13045 (62 FR 19885, April 23, 1997) as applying only to those regulatory actions that concern health or safety risks, such that the analysis required under section 5-501 of the EO has the potential to influence the regulation. This action is not subject to EO 13045 because it does not establish an environmental standard intended to mitigate health or safety risks. This action simply clarifies certain requirements in the final rule and corrects typographical errors.

H. Executive Order 13211: Actions Concerning Regulations That Significantly Affect Energy Supply, Distribution, or Use

This action is not subject to Executive Order 13211 (66 FR 28355 (May 22, 2001)), because it is not a significant regulatory action under Executive Order 12866.

I. National Technology Transfer and Advancement Act

Section 12(d) of the National Technology Transfer and Advancement Act of 1995 (NTTAA), Public Law 104-113, 12(d) (15 U.S.C. 272 note) directs the EPA to use voluntary consensus standards (VCS) in its regulatory activities, unless to do so would be inconsistent with applicable law or otherwise impractical. The VCS are technical standards (e.g., materials specifications, test methods, sampling procedures, and business practices) that are developed or adopted by VCS bodies. NTTAA directs the EPA to provide Congress, through OMB, explanations when the agency decides not to use available and applicable VCS.

This action does not involve technical standards. Therefore, EPA did not consider the use of any VCS.

J. Executive Order 12898: Federal Actions To Address Environmental Justice in Minority Populations and Low-Income Populations

Executive Order 12898 (59 FR 7629, February 16, 1994) establishes federal executive policy on environmental justice. Its main provision directs federal agencies, to the greatest extent practicable and permitted by law, to make environmental justice part of their mission by identifying and addressing, as appropriate, disproportionately high and adverse human health or environmental effects of their programs, policies and activities on minority populations and low-income populations in the United States.

EPA has determined that this final rule will not have disproportionately high and adverse human health or environmental effects on minority or low-income populations because it does not affect the level of protection provided to human health or the environment. This action merely corrects and clarifies existing requirements, it does not change any regulatory requirements.

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. The EPA will submit a report containing this final rule and other required information to the United States Senate, the United States House of Representatives and the Comptroller General of the United States prior to publication of the direct 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). The final rule will be effective on March 4, 2014.

List of Subjects for 40 CFR Part 63

• Environmental protection
• Administrative practice and procedures
• Air pollution control
• Hazardous substances
• Intergovernmental relations
• Reporting and recordkeeping requirements

Dated: December 20, 2013.

Gina McCarthy,

Administrator.

For the reasons stated in the preamble, part 63 of title 40, chapter I, of the Code of Federal Regulations is amended as follows:

PART 63—NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS FOR SOURCE CATEGORIES

1. The authority citation for part 63 continues to read as follows:

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

2. Amend § 63.542 by revising the definition of “Windward wall” to read as follows:

§ 63.542

Definitions.

* * * * *

Windward wall means the exterior wall of a total enclosure that is most impacted by the wind in its most prevailing direction determined by a wind rose using available data from the closest representative meteorological station. When openings into enclosures are not impacted by ambient wind due to the enclosure being part of a larger structure, the owner or operator may designate which wall of the enclosure to define as the windward wall.

3. Amend § 63.543 by revising paragraph (f) to read as follows:

§ 63.543

What are my standards for process vents?

* * * * *

(f) If you do not combine the furnace charging process fugitive emissions with the furnace process emissions, and discharge such emissions to the atmosphere through separate emissions points, you must maintain the total hydrocarbons concentration in the exhaust gas at or below 20 parts per million by volume, expressed as propane.

* * * * *

4. Amend § 63.544 by revising the first sentence of paragraph (c) introductory text and adding paragraph (c)(3) to read as follows:

§ 63.544

What are my total enclosure standards?

* * * * *

(c) You must construct and operate total enclosures for the sources listed in paragraph (a) of this section as specified in paragraphs (c)(1) through (3) of this section.* * *

* * * * *

(3) If areas that contain one or more sources listed in paragraphs (a)(1) through (9) of this section are enclosed within a larger building that also meets the definition of a total enclosure under § 63.542, the requirements of paragraphs (c)(1) and (2) shall be monitored pursuant to § 63.548(k) at only one leeward, one windward and one additional wall of the outermost portion of the larger totally enclosed building rather than each individual area within the building.

* * * * *

5. Amend § 63.546 by adding paragraph (c) to read as follows:

§ 63.546

Compliance dates.

* * * * *

(c) Until the date specified in 63.546(a), secondary lead smelters that commenced construction or reconstruction on or before May 19, 2011, must continue to demonstrate compliance with the requirements of this subpart, codified in 40 CFR 63.541 through 40 CFR 63.550, that were in effect prior to the January 5, 2012, amendments. This means that secondary lead smelters that commenced construction or reconstruction on or before June 9, 1994, must continue to demonstrate compliance with existing source requirements of this subpart that were in effect prior to the January 5, 2012, amendments until the date specified in § 63.546(a). Secondary lead smelters that commenced construction or reconstruction after June 9, 1994, and on or before May 19, 2011, must continue to demonstrate compliance with new source requirements of this subpart that were in effect prior to the January 5, 2012, amendments until the date specified in § 63.546(a).

6. Amend § 63.548 by revising paragraphs(k)(1)(iii), (k)(3), (k)(4) and (k)(5) to read as follows:

§ 63.548

Monitoring requirements.

* * * * *

(k) * * *

(1) * * *

(iii) An exterior wall that connects the leeward and windward wall at a location defined by the intersection of a perpendicular line between a point on the connecting wall and a point on its furthest opposite exterior wall, and intersecting within plus or minus 10 meters of the midpoint of a straight line between the two other monitors specified. The midpoint monitor must not be located on the same wall as either of the other two monitors. If approved by the permitting authority, this third monitor may be placed in an alternative location on the midpoint wall or an exterior wall that is not the windward wall, leeward wall or midpoint wall.

* * * * *

(3) The digital differential pressure monitoring systems must be certified by the manufacturer to be capable of measuring and displaying negative pressure containing values in the range of 0.01 to 0.2 millimeters mercury (0.005 to 0.11 inches of water) and capable of recording data in increments of 0.002 millimeters of mercury (0.001 inches of water).

(4) You must equip each digital differential pressure monitoring system with a continuous recorder. To demonstrate compliance with the standard for differential pressure, you must maintain the pressure in total enclosures such that the average pressure in any 15-minute period does not fall below the level specified in § 63.544(c)(1). The 15-minute averages must include at least one reading per minute.

(5) You must calibrate each digital differential pressure monitoring system in accordance with manufacturer's specifications.

* * * * *

7. Section 63.550 is amended by revising paragraph (e)(10) to read as follows:

§ 63.550

Recordkeeping and reporting requirements.

* * * * *

(e) * * *

(10) Records of 15-minute periods when the pressure was not maintained as required in § 63.544(c) or power was lost to the continuous pressure monitoring system as required in § 63.548(k). Records of which wall is chosen as the windward wall must be included in the records required by § 63.10(c) if a total enclosure located within a larger structure is not impacted by ambient wind.

* * * * *

8. Amend Table 3 to Subpart X of Part 63—Toxic Equivalency Factors by revising to read as follows:

Table 3 to Subpart X of Part 63—Toxic Equivalency Factors

Dioxin/furan congener	Toxic equivalency factor
2,3,7,8-tetrachlorinated dibenzo-p-dioxin	1
1,2,3,7,8-pentachlorinated dibenzo-p-dioxin	1
1,2,3,4,7,8-hexachlorinated dibenzo-p-dioxin	0.1
1,2,3,7,8,9-hexachlorinated dibenzo-p-dioxin	0.1
1,2,3,6,7,8-hexachlorinated dibenzo-p-dioxin	0.1
1,2,3,4,6,7,8-heptachlorinated dibenzo-p-dioxin	0.01
octachlorinated dibenzo-p-dioxin	0.0003
2,3,7,8-tetrachlorinated dibenzofuran	0.1
2,3,4,7,8-pentachlorinated dibenzofuran	0.3
1,2,3,7,8-pentachlorinated dibenzofuran	0.03
1,2,3,4,7,8-hexachlorinated dibenzofuran	0.1
1,2,3,6,7,8-hexachlorinated dibenzofuran	0.1
1,2,3,7,8,9-hexachlorinated dibenzofuran	0.1
2,3,4,6,7,8-hexachlorinated dibenzofuran	0.1
1,2,3,4,6,7,8-heptachlorinated dibenzofuran	0.01
1,2,3,4,7,8,9-heptachlorinated dibenzofuran	0.01
octachlorinated dibenzofuran	0.0003