***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review***

E.O. 12866 Landfills EG 2060 AS23 NPRM 2015 06170813

6560-50-P

ENVIRONMENTAL PROTECTION AGENCY 40 CFR Part 60 [EPA-HQ-OAR-2014-0451; FRL- 9930-64-OAR ] RIN 2060-AS23 Emission Guidelines and Compliance Times for Munici pal Solid

Waste Landfills

AGENCY: Environmental Protection Agency.

ACTION: Proposed rule.

SUMMARY : The Environmental Protection Agency (EPA) is proposing a new subpart, 40 CFR part 60, subpart Cf that updates the Emission Guidelines and Compliance Times for Mu nicipal Solid Waste Landfills (40 CFR part 60, subpart Cc) (Emiss ion Guidelines). The EPA determined that it was appropr iate to

review the landfills Emission Guidelines based on c hanges in the landfills industry since the Emission Guidelines we re promulgated in 1996. The EPA’s review of the Emissi on Guidelines for municipal solid waste landfills applies to land fills that accepted waste after November 8, 1987 and commenced construction, reconstruction, or modification on or before July 17, 2014. Based on its initial review, the EPA has determined that it is appropriate to propose revisions to the Emission Guidelines that reflect changes to the population o f landfills***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 2 of 324 and the results of an analysis of the timing and me thods for reducing emissions. This action proposes to achieve additional reductions of landfill gas and its components, incl uding methane, by lowering the emissions threshold at whi ch a landfill must install controls. This action also incorporate s new data and information received in response to an advancednotice of proposed rulemaking and addresses other regulatory issues including surface emissions monitoring, wellhead mo nitoring, and the definition of landfill gas treatment system. In addition to considering information received in response to this proposed rule in evaluating potential chang es to the Emission Guidelines, the EPA intends to consider th e information in evaluating whether changes to the requirements f or new sources beyond those in the July 17, 2014 proposed rule (79 FR 41796) for new sources are warranted. The proposed revisions to the Emission Guidelines, once implemented through revised state plans or a revise d federal plan, would reduce emissions of landfill gas, which contains both nonmethane organic compounds and methane. Land fills are a significant source of methane and methane is a pote nt greenhouse gas pollutant. These avoided emissions will improve air quality and reduce public health and welfare effects associ ated with exposure to landfill gas emissions.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 3 of 324

DATES: Comments. Comments must be received on or before [ insert date 60 days after date of publication in the Feder al Register ]. Public Hearing. If anyone contacts the EPA requesti ng a public hearing by [ insert date 5 days after date of publication in the Federal Register ], the EPA will hold a public hearing on [ insert date 15 days after date of publication in the Feder al Register ] from 1:00 p.m. (Eastern Standard Time) to 5:00 pm (Eastern Standard Time) at the U.S. Environmental P rotection Agency building located at 109 T.W. Alexander Drive , Research Triangle Park, NC 27711. Information regarding whether or not a hearing will be held will be posted on the rule’s w ebsite located at http://www.epa.gov/ttnatw01/landfill/lan dflpg.htm.

ADDRESSES: Submit your comments, identified by Docket ID No. EPA-HQ-OAR-2014-0451, to the Federal eRulemaking Portal: http://www.regulations.gov. Follow the online instr uctions for submitting comments. Once submitted, comments canno t be edited or withdrawn. The EPA may publish any comment recei ved to its public docket. Do not submit electronically any inf ormation you consider to be Confidential Business Information (C BI) or other information whose disclosure is restricted by statu te. Multimedia submissions (audio, video, etc.) must be accompanied by a written comment. The written comment is consid ered the

official comment and should include discussion of a ll points you wish to make. The EPA will generally not consider c omments or***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 4 of 324 comment contents located outside of the primary sub mission (i.e., on the web, cloud, or other file sharing sys tem). For additional submission methods, the full EPA public comment policy, information about CBI or multimedia submiss ions, and general guidance on making effective comments, plea se visit http://www2.epa.gov/dockets/commenting-epa-dockets. by one of the following methods:

• Federal eRulemaking Portal: http://www.regulations. gov. Follow the online instructions for submitting comme nts.

• Email: A-and-R-docket@epa.gov. Include docket ID No . EPA– HQ–OAR–2014-0451 in the subject line of the message

.

• Fax: (202) 566–9744. Attention Docket ID No. EPA–HQ –OAR– 2014-0451.

• Mail: Environmental Protection Agency, EPA Docket C enter (EPA/DC), Mail Code 28221T, Attention Docket ID No. EPA–HQ– OAR–2014-0451, 1200 Pennsylvania Avenue, NW, Washin gton, DC 20460. In addition, please mail a copy of your comm ents on the information collection provisions to the Office of Information and Regulatory Affairs, Office of Manag ement and Budget, Attn: Desk Officer for EPA, 725 17 th Street, NW, Washington, DC 20503.

• Hand/Courier Delivery: EPA Docket Center, Room 3334 , EPA WJC West Building, 1301 Constitution Avenue, NW, Washington, DC 20004. Such deliveries are only acce pted 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 No. EPA–HQ– OAR–2014-0451. The EPA’s policy is that all comment s received will be included in the public docket without chang e and may be made available online at http://www.regulations.gov , including any personal information provided, unless the comme nt includes

information claimed to be confidential business inf ormation Formatted: Default Paragraph Font, No underline

Formatted: Space After: 4 pt***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 5 of 324 (CBI) or other information whose disclosure is rest ricted by

statute. Do not submit information that you consider to be C BI or otherwise protected through http://www.regulations. gov or email.

Send or deliver information identified as CBI to on ly the mail or hand/courier delivery address listed above, atte ntion: OAQPS Document Control Officer (Room C404-02), Office of Air Quality Planning and Standards, U.S. EPA, Research Triangle Park, NC 27711, Attention Docket ID No. EPA-HQ-OAR-2014-0451 . The http://www.regulations.gov Web site is an “anonymou s access” system, which means the EPA will not know your iden tity or contact information unless you provide it in the bo dy of your comment. If you send an email comment directly to t he EPA without going through http://www.regulations.gov, y our email address will be automatically captured and includedas part of the comment that is placed in the public docket andmade available on the Internet. If you submit an electro nic comment, the EPA recommends that you include your name and o ther contact information in the body of your comment and with an y disk or CD– ROM you submit. If the EPA cannot read your comment due to technical difficulties and cannot contact you for c larification, the EPA may not be able to consider your comment. E lectronic files should avoid the use of special characters, a ny form of encryption, and be free of any defects or viruses.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 6 of 324 Public Hearing. If anyone contacts the EPA requesti ng a public hearing by [ insert date 5 days after date of publication in the Federal Register ], the EPA will hold a public hearing on [ insert date 15 days after date of publication in th e Federal Register ] from 1:00 p.m. (Eastern Standard Time) to 5:00 p. m. (Eastern Standard Time) at the U.S. Environmental P rotection Agency building located at 109 T.W. Alexander Drive , Research Triangle Park, NC 27711. If no one contacts the EPA requesting a public hearing to be held concerning this proposed rule by [ insert date 5 days after date of publication in the Federa l Register ], a public hearing will not take place. Information regarding whether or not a hearing will be held wil l be posted

on the rule’s website located at http://www.epa.gov/ttnatw01/landfill/landflpg.htm. Please contact Ms. Aimee St. Clair at (919) 541-106 3 or at stclair.aimee@epa.gov to register to speak at the h earing. The last day to pre-register to speak at the hearing wi ll be [ insert date 12 days after date of publication in the Feder al Register ]. Requests to speak will be taken the day of the hear ing at the hearing registration desk, although preferences on speaking times may not be able to be fulfilled. If you requi re the service of a translator or special accommodations s uch as audio description, please let us know at the time of regi stration.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 7 of 324 If a hearing is held, it will provide interested pa rties the opportunity to present data, views or arguments concerning the proposed action. The EPA will make every effort to accommodate all speakers who arrive and register. B ecause this hearing, if held, will be at U.S. government facili ties, individuals planning to attend the hearing should b e prepared to show valid picture identification to the security s taff in order to gain access to the meeting room. Please note tha t the REAL ID Act, passed by Congress in 2005, established new re quirements for entering federal facilities. If your driver’s l icense is issued by Alaska, American Samoa, Arizona, Kentucky , Louisiana, Maine, Massachusetts, Minnesota, Montana, New York, Oklahoma or the state of Washington, you must present an additi onal form of identification to enter the federal building. Accep table

alternative forms of identification include: Federa l employee badges, passports, enhanced driver’s licenses and m ilitary identification cards. In addition, you will need to obtain a property pass for any personal belongings you bring with you. Upon leaving the building, you will be required to return this property pass to the security desk. No large signs will be allowed in the building, cameras may only be used o utside of the building and demonstrations will not be allowed on federal property for security reasons.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 8 of 324 The EPA may ask clarifying questions during the ora l presentations, but will not respond to the presenta tions at that time. Written statements and supporting information submitted during the comment period will be considered with t he same weight as oral comments and supporting information presented at the public hearing. Commenters should notify Ms. St . Clair if they will need specific equipment, or if there are other special needs related to providing comments at the hearings . Verbatim transcripts of the hearing and written statements w ill be included in the docket for the rulemaking. The EPA will make every effort to follow the schedule as closely as p ossible on the day of the hearing; however, please plan for th e hearing to

run either ahead of schedule or behind schedule. A public hearing will not be held unless requested. Please c ontact Ms. Aimee St. Clair at (919) 541-1063 or at stclair.aim ee@epa.gov to request or register to speak at the hearing or to i nquire as to whether a hearing will be held. Again further information on the public hearing will be provided on the rule’s websi te located at http://www.epa.gov/ttnatw01/landfill/landflpg.html.

Docket: All documents in the docket are listed in t he http://www.regulations.gov index. Although listed i n the index, some information is not publicly available, e.g., C BI or other information whose disclosure is restricted by statu te. Certain other material, such as copyrighted material, will be publicly***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 9 of 324 available only in hard copy. Publicly available doc ket materials are available either electronically in http://www.regulations.gov or in hard copy at the E PA Docket Center, EPA/DC, EPA WJC West Building, Room 3334, 1 301 Constitution Ave., NW, Washington, DC. This Docket Facility is open from 8:30 a.m. to 4:30 p.m., Monday through Fr iday, excluding legal holidays. The telephone number for the Public Reading Room is (202) 566–1744, and the telephone n umber for the Air Docket is (202) 566–1742.

FOR FURTHER INFORMATION CONTACT: For information concerning this proposal, contact Ms. Hillary Ward, Fuels and Incin eration Group, Sector Policies and Programs Division, Offic e of Air Quality Planning and Standards (E143-05), Environme ntal Protection Agency, Research Triangle Park, NC 27711 ; telephone number: (919) 541-3154; fax number: (919) 541-0246; email address: ward.hillary@epa.gov.

SUPPLEMENTARY INFORMATION: Acronyms and Abbreviations. The following acronyms and

abbreviations are used in this document.

ACUS Administrative Conference of the United States ANPRM Advance notice of proposed rulemaking ANSI American National Standards Institute ARB Air Resources Board BMP Best management practice BSER Best system of emission reduction Btu British thermal unit CAA Clean Air Act CA LMR California Landfill Methane Rule***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 10 of 324

CBI Confidential business information CDX Central Data Exchange CEA Council of Economic Advisers CEDRI Compliance and Emissions Data Reporting Inter face CFR Code of Federal Regulations CO 2 Carbon dioxide CO 2 e Carbon dioxide equivalent DOC Degradable organic carbon EPA Environmental Protection Agency ERT Electronic Reporting Tool GCCS Gas collection and control system GHG Greenhouse gas GHGRP Greenhouse Gas Reporting Program GWP Global warming potential HAP Hazardous air pollutant HOV Higher operating value IAMS Integrated assessment models ICR Information collection request IPCC Intergovernmental Panel on Climate Change IRFA Initial regulatory flexibility analysis IWG Interagency working group lb/MMBtu Pounds per million British thermal unit LCRS Leachate collection and removal system LFG Landfill gas LFGCost Landfill Gas Energy Cost Model LMOP Landfill Methane Outreach Program

m 3 Cubic meters Mg Megagram Mg/yr Megagram per year mph Miles per hour MSW Municipal solid waste mtCO 2 e Metric tons of carbon dioxide equivalent MW Megawatt MWh Megawatt hour NAICS North American Industry Classification System NMOC Nonmethane organic compound NRC National Research Council NSPS New source performance standards***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 11 of 324 NTTAA National Technology Transfer and Advancement Act OAQPS Office of Air Quality Planning and Standards OMB Office of Management & Budget PM Particulate matter PM 2.5 Fine particulate matter ppm Parts per million ppmvd Parts per million by dry volume RCRA Resource Conservation and Recovery Act RFA Regulatory Flexibility Act RFS Renewable Fuel Standard RIA Regulatory Impacts Analysis SBAR Small Business Advocacy Review SC-CH 4 Social cost of methane SC-CO 2 Social cost of carbon dioxide SEM Surface emissions monitoring SER Small entity representative SO 2 Sulfur dioxide SSM Startup, shutdown and malfunction Tg Teragram TIP Tribal implementation plan TTN Technology Transfer Network U.S. United States USGCRP U.S. Global Change Research Program VCS Voluntary consensus standard VOC Volatile organic compound WWW World Wide Web Organization of This Document. The following outlin e is provided to aid in locating information in this pre amble.

I. Executive Summary A. Purpose of Regulatory Action B. Summary of Major Provisions C. Costs and Benefits II. General Information A. Does this action apply to me? B. What should I consider as I prepare my comments?***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 12 of 324 C. Where can I get a copy of this document and othe r related information? III. Background A. Landfill Gas Emissions and Climate Change B. What are the health and welfare effects of landf ill gas emissions? C. What is EPA’s authority for reviewing the Emissi on Guidelines? D. What is the purpose and scope of this action? E. How would the proposed changes in applicability affect sources currently subject to subparts Cc and WWW? F. Where in the CFR will these changes appear? IV. Summary of Proposed Changes Based on Review of the Emission Guidelines A. Control Technology Review B. Proposed changes to Monitoring, Recordkeeping, a nd Reporting C. Emission Threshold Determinations D. Proposed Changes to Address Closed or Non-Produc ing Areas E. Other Proposed Changes V. Rationale for the Proposed Changes Based on GCCS Technology Review A. Control Technology Review B. What data and control costs did the EPA consider in evaluating potential changes to the timing of insta lling, expanding, and removing the GCCS? C. What emissions and emission reduction programs a re associated with existing MSW landfills? D. What control options did the EPA consider? VI. Rationale for the Proposed Changes to Monitorin g, Recordkeeping, and Reporting A. Surface Emissions Monitoring Requirements B. Wellhead Monitoring Requirements C. Requirements for Updating the Design Plan D. Submitting Corrective Action Timeline Requests E. Electronic Reporting VII. Rationale for Proposed Alternative Emission Th reshold Determination Techniques VIII. Proposed Changes to Address Closed or Non-Pro ducing Areas A. Subcategory for Closed Landfills B. Criteria for Capping or Removing a GCCS***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 13 of 324 C. Non-producing Areas and Wellhead Standards IX. Rationale for the Other Proposed Changes A. Landfill Gas Treatment B. Startup, Shutdown, and Malfunction C. Definitions and Other Rule Changes. X. Request for Comment on Specific Provisions A. Defining Closed Areas of Open Landfills. B. Enhanced Surface Emissions Monitoring C. Wet Landfills D. Monitoring Wellhead Flowrate E. Third Party Design Plan Certification Program F. Use of Portable Analyzers for Monitoring Oxygen XI. Impacts of Proposed Revisions A. What are the air quality impacts? B. What are the water quality and solid waste impac ts? C. What are the secondary air impacts? D. What are the energy impacts? E. What are the cost impacts? F. What are the economic impacts? G. What are the benefits? XII. Statutory and Executive Order Reviews A. Executive Order 12866: Regulatory Planning and R eview and Executive Order 13563: Improving Regulation and Reg ulatory Review B. Paperwork Reduction Act (PRA) C. Regulatory Flexibility Act (RFA) D. Unfunded Mandates Reform Act (UMRA) E. Executive Order 13132: Federalism F. Executive Order 13175: Consultation and Coordina tion with Indian Tribal Governments G. Executive Order 13045: Protection of Children fr om Environmental Health Risks and Safety Risks H. Executive Order 13211: Actions that Significantl y Affect Energy Supply, Distribution, or Use I. National Technology Transfer and Advancement Act J. Executive Order 12898: Federal Actions to Addres s Environmental Justice in Minority Populations and L ow-Income Populations I. Executive Summary***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 14 of 324 A. Purpose of Regulatory Action This action proposes changes to the MSW landfills E mission Guidelines resulting from the EPA’s review of the E mission

Guidelines under Clean Air Act section 111. The EPA ’s review identified a number of advances in technology and o perating practices and the proposed changes are based on our evaluation of those advances and our understanding of landfill gas (LFG) emissions. The resulting changes to the Emission Gu idelines, if adopted, will achieve additional reductions in emis sions of landfill gas and its components, including methane. This proposed rule is consistent with the President’s 20 13 Climate

Action Plan 1 , which directs federal agencies to focus on “assessing current emissions data, addressing data gaps, identifying technologies and best practices for red ucing emissions, and identifying existing authorities and incentivebased opportunities to reduce methane emissions.” T he proposed changes are also consistent with the President’s Me thane Strategy 2 , which directs EPA’s regulatory and voluntary prog rams to continue to pursue emission reductions through r egulatory

1 Executive Office of the President, “The President’ s Climate Action Plan” June 2013. https://www.whitehouse.gov/sites/default/files/imag e/president27sclimateactio nplan.pdf 2 Executive Office of the President, “Climate Action Plan Strategy to Reduce Methane, March 2014. https://www.whitehouse.gov/sites/default/files/stra tegy_to_reduce_methane_emi ssions_2014-03-28_final.pdf***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 15 of 324 updates and to encourage LFG energy recovery throug h voluntary programs. These directives are discussed in detail in section III.A of this preamble. This regulatory action also proposes to either resolve or clarify implementation issues tha t were previously addressed in amendments proposed on May 23, 2002 (67 FR 36475) and September 8, 2006 (71 FR 53271). 1. Need for Regulatory Action

The EPA reviewed the Emission Guidelines to determi ne the potential for achieving additional reductions in em issions of LFG. Such reductions would reduce air pollution and the resulting harm to public health and welfare. Signif icant changes have occurred in the landfill industry over time, i ncluding changes to the size and number of existing landfill s, industry practices, and gas control methods and technologies . Based on the EPA’s initial review, we are proposing changes to the Emission Guidelines. The proposed changes, if adopt ed, will

achieve additional emission reductions of LFG and i ts components (including methane), provide more effective options for demonstrating compliance, and provide clarification of implementation issues raised during the amendments proposed in

2002 and 2006. 2. Legal Authority The EPA is not statutorily obligated to conduct a r eview of the Emission Guidelines, but has the discretion to do so when***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 16 of 324 circumstances indicate that it is appropriate. The EPA has determined that it is appropriate to review and pro pose changes

to the Emission Guidelines at this time based on ch anges in the landfill industry and changes in the size, ownershi p, and age of landfills since the Emission Guidelines were promul gated in 1996. The EPA compiled new information on landfills through data collection efforts for a statutorily mandated revie w of the existing new source performance standards (NSPS) (4 0 CFR part 60, subpart WWW), public comments received on the N SPS proposal (79 FR 41796, July 17, 2014), and public comments r eceived on the Advanced Notice of Proposed Rulemaking (ANPRM) (79 FR 41772, July 17, 2014) for a review of the Emission Guideli nes. This information is allowing the EPA to assess current p ractices, emissions, and the potential for additional emissio n reductions. B. Summary of Major Provisions The proposed revised Emission Guidelines will ultim ately apply to landfills that accepted waste after Novemb er 8, 1987 3 , and that commenced construction, reconstruction, or modification on or before July 17, 2014 (the date of publication of proposed

3 This date in 1987 is the date on which permit prog rams were established under the Hazardous and Solid Waste Amendments of t he Resource, Conservation and Recovery Act (RCRA) which amended the Solid Was te Disposal Act (SWDA), 42 U.S.C. §§ 6901 – 6992k. This date was also selected as the regulatory cutoff in the EG for landfills no longer receiving wastes because the EPA judged States would be able to identify active facilities as of this date.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 17 of 324 revisions to the landfills NSPS, 40 CFR part 60, su bpart XXX). The proposed rule provisions are described below. Thresholds for installing or removing controls. The proposed revised Emission Guidelines retain the cur rent design capacity threshold of 2.5 million megagrams (Mg) an d 2.5 million cubic meters (m 3 ), but reduce the nonmethane organic compounds (NMOC) emission threshold for the installation and removal of a gas collection and control system (GCCS) from 50 Mg /yr to 34 Mg/yr for landfills that are not closed. As propose d, a municipal solid waste (MSW) landfill that exceeds t he design capacity threshold must install and start up a GCCS within 30 months after landfill gas (LFG) emissions reach or exceed an NMOC level of 34 Mg/yr NMOC. (A megagram is also kn own as a metric ton, which is equal to 1.1 U.S. short tons o r about 2,205 pounds.) Consistent with the existing Emission Guid elines, the owner or operator of a landfill may control the gas by routing it to a non-enclosed flare, an enclosed combustion device, or a treatment system that processes the collected gas f or subsequent

sale or beneficial use. Landfill Gas Treatment. The EPA is proposing to add ress two issues related to LFG treatment. First, the EPA is proposing to clarify that the use of treated LFG is not limited to use as a fuel for a stationary combustion device but also al lows other beneficial uses such as vehicle fuel, production of high-Btu gas***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 18 of 324 for pipeline injection, and use as a raw material i n a chemical manufacturing process. Second, the EPA is proposing to define Treated landfill gas as landfill gas processed in a treatment system meeting the requirements in 40 CFR part 60, subpart Cf and to define Treatment system as a system that fil ters, dewaters, and compresses landfill gas for sale or ben eficial use. The proposed definition allows the level of treatme nt to be tailored to the type and design of the specific com bustion equipment or other equipment for other beneficial uses such as vehicle fuel, production of high-Btu gas for pipeli ne injection,

or use as a raw material in a chemical manufacturing process in which the landfill gas is used. Owners and operator s would develop a site-specific treatment system monitoring plan that would include monitoring parameters addressing all three elements of treatment (filtration, de-watering, andcompression) to ensure the treatment system is operating properl y for the intended end use of the treated LFG. They would als o keep records that demonstrate that such parameters effec tively monitor filtration, de-watering, and compression sy stem performance necessary for the end use of the treate d landfill

gas. Surface Monitoring. The EPA proposes monitoring of all surface penetrations for existing landfills. In pro posed 40 CFR part 60, subpart Cf, landfills must conduct surface emissions Commented [A1]: OMB General Comment 7. Reviewer recommends including broader language (beyond combustion and chemical manufacturing) in the below sentence on page 17 of the emission guidelines to clarify that treated landfill gas can be used in a variety of ways including vehicle fuel, production of high- Btu gas for pipeline injection, and other beneficial uses. Response: Additional text has been added here to broaden the language.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 19 of 324 monitoring (SEM) at all cover penetrations and open ings within the area of the landfill where waste has been place d and a gas collection system is required to be in place and op erating according to the operational standards in proposed 40 CFR part 60, subpart Cf. Specifically, landfill owners/opera tors must conduct surface monitoring on a quarterly basis at the specified

intervals and where visual observations indicate el evated concentrations of landfill gas, such as distressed vegetation and cracks or seeps in the cover and all cover pene trations. Emission Threshold Determination. The EPA is propos ing an alternative site-specific emission threshold determ ination for when a landfill must install and operate a GCCS. Th is alternative emission threshold determination, refer red to as “Tier 4,” is based on surface emission monitoring a nd demonstrates that surface emissions are below a spe cific

threshold. The Tier 4 SEM demonstration would allowlandfills that exceed modeled NMOC emission rates using Tiers 1, 2, or 3 to demonstrate that site-specific surface methane e missions are

low. A landfill that can demonstrate that surface e missions are below 500 parts per million (ppm) for 4 consecutive quarters would not trigger the requirement to install a GCCS even if Tier 1, 2, or 3 calculations indicate that the 34 Mg/yr threshold has

been exceeded.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 20 of 324 Wellhead Operational Standards. The EPA proposes to remove the operational standards (i.e., the requirement to meet operating limits) for temperature and nitrogen/oxyg en at the wellheads. Landfill owners and operators would not be required

to take corrective action based on exceedances of s pecified operational standards, but they would continue to m onitor temperature and oxygen/nitrogen levels at wellheads in order to inform any necessary adjustments to the GCCS and wo uld maintain records of monthly readings. The operational standa rd, corrective action, and corresponding recordkeeping and reporting remain for maintaining negative pressure at the wel lhead. Closed Landfills. Because many landfills are closedand do not produce as much LFG, the EPA is proposing a sep arate subcategory for landfills that closed on or before [insert date of publication in the Federal Register]. Landfills in this subcategory will continue to be subject to an NMOC emission threshold of 50 Mg/yr for determining when controls must be

installed or can be removed. Low LFG Producing Areas. The EPA is also proposing alternative criteria for determining when it is app ropriate to cap or remove a portion of the GCCS at such landfil ls. The proposed alternative criteria for capping or removi ng the GCCS are: 1) the landfill is closed or an area of an act ive landfill is closed, 2) the GCCS has operated for at least 15 years or the***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 21 of 324 landfill owner/operator can demonstrate that the GC CS will be unable to operate for 15 years due to declining gas flows, and 3) the landfill owner/operator demonstrates that th ere are no surface methane emissions of 500 ppm or greater in the landfill or closed area for 4 consecutive quarters. Startup, Shutdown, and Malfunction. The EPA is prop osing that standards in the Emission Guidelines apply at all times, including periods of startup, shutdown, and malfunc tion. In addition, to enable the EPA to determine the severi ty of any emissions exceedance that might occur during period s when the gas collection system or a control device is not op erating, the EPA is proposing to add a recordkeeping and reporti ng requirement for landfill owners or operators to est imate emissions during such periods. Requests for Comment. The EPA welcomes comments on all aspects of this proposal and is specifically reques ting comments on the following topics:

• Defining closed areas of open landfills.

• Changing the walking pattern for surface emissions monitoring from 30 meters (98 ft) to 25 ft and addi ng a methane concentration limit of 25 ppm as determinedby an integrated reading.

• Addressing wet landfills.

• Monitoring wellhead flow rate.

• Establishing a program for third party design plan certification.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 22 of 324

• Using a portable gas composition analyzer as accept able alternative to Method 3A or 3C.

Other Clarifications. The EPA is proposing other

clarifications to address issues that have been rai sed by landfill owners or operators during implementation of the

current NSPS and Emission Guidelines. These other c larifications include adding criteria for when an affected source must update its design plan and clarifying when landfill owners or operators must submit corrective action timeline requests. Th e EPA is also proposing to update several definitions in the Emis sion Guidelines. In addition, while the EPA is not propo sing to mandate organics diversion we are proposing two spe cific compliance flexibilities in the Emission Guidelines to encourage wider adoption of organics diversion and GCCS Best Management Practices (BMPs) for emission reductions at landfil ls. These compliance flexibilities are discussed in sections VI.B (wellhead monitoring) and VII.A (Tier 4 emission th reshold determination) of this preamble.

C. Costs and Benefits The proposed revised Emission Guidelines are expect ed to significantly reduce emissions of landfill gas and its components, which include methane, volatile organic compounds (VOC), and hazardous air pollutants (HAP). Landfill s are a significant source of methane emissions, and in 201 3, landfills***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 23 of 324 represented the third largest source of human-relat ed methane

emissions in the U.S. To comply with the emissions limits in the proposedrule, MSW landfill owners or operators are expected to in stall the least-cost control for collecting and combusting la ndfill gas. The annualized net cost for the proposed Emission G uidelines is estimated to be $46.8 million (2012$) in 2025, when using a 7 percent discount rate. The annualized costs represe nt the costs compared to no changes to the current Emission Guid elines (i.e., baseline) and include $101 million to install and o perate a GCCS, as well as $0.64 million to complete the corr esponding testing and monitoring. These control costs are off set by $55.3 million in revenue from electricity sales, which is incorporated

into the net control costs for certain landfills th at are expected to generate revenue by using the landfill gas to produce electricity. Installation of a gas collection and control system to comply with the 34 Mg/yr NMOC emissions threshold a t open landfills would achieve reductions of 2,770 Mg/yr N MOC and 436,100 Mg/yr methane (about 10.9 million metric to ns of carbon dioxide equivalent per year (mtCO 2 e/yr)) beyond the baseline in year 2025. In addition, the proposal is expected to result in the net reduction of 238,000 Mg CO 2 , due to reduced demand for electricity from the grid as landfills generate ele ctricity from***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 24 of 324 landfill gas. The NMOC portion of landfill gas can contain a variety of air pollutants, including VOC and variou s organic HAP. VOC emissions are precursors to both fine part iculate matter (PM 2.5 ) and ozone formation. These pollutants, along with methane, are associated with substantial health eff ects, welfare effects, and climate effects. The EPA expects that the reduced emissions will result in improvements in air qualit y and lessen health effects associated with exposure to air poll ution related emissions, and result in climate benefits due to re ductions of the methane component of landfill gas. The EPA estimates that the proposal’s estimated met hane emission reductions and secondary CO 2 emission reductions in the year 2025 would yield global monetized climate bene fits of $310 million to approximately $1.7 billion, depending on the discount rate. Using the mean social cost of methane (SC-CH 4 ) and social

cost of CO 2 (SC- CO 2 ), at a 3-percent discount rate, results in an estimate of about $670 million in 2025.

The SC-CH 4 and SC-CO 2 are the monetary values of impacts associated with marginal changes in methane and CO 2 emissions, respectively, in a given year. It includes a wide r ange of anticipated climate impacts, such as net changes in agricultural productivity, property damage from increased flood risk, and***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 25 of 324 changes in energy system costs, such as reduced cos ts for heating and increased costs for air conditioning. With the data available, we are not able to provide health benefit estimates for the reduction in exposure to HAP, ozone,

and PM 2.5 for this rule. This is not to imply that there are no such benefits of the rule; rather, it is a reflecti on of the difficulties in modeling the direct and indirect impacts of the

reductions in emissions for this sector with the da ta currently

available. Based on the monetized benefits and costs, the esti mated net benefits of the rule are estimated to be $620 m illion ($2012) in 2025.

II. General Information A. Does this action apply to me? This proposed rule addresses existing MSW landfills and associated solid waste management programs. Potenti ally affected categories include those listed in Table 1 of this preamble. Table 1. Regulated Entities Category NAICS a Examples of affected facilities Industry: Air and water resource and solid waste management 924110 Solid waste landfills

Industry: Refuse systems--solid waste landfills 562212 Solid waste landfills***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 26 of 324 Category NAICS a Examples of affected facilities State, local, and tribal government agencies 924110 Administration of air and water resource and solid waste management programs

a North American Industry Classification System. This table is not intended to be exhaustive, but ra ther provides a guide for readers regarding entities lik ely to be regulated by the new subpart. To determine whether your facility would be regulated by this action, you should caref ully examine the applicability criteria in proposed 40 CFR 60.32 f of subpart Cf. If you have any questions regarding the applica bility of the proposed subpart to a particular entity, contact th e person listed in the preceding FOR FURTHER INFORMATION CONTACT section. B. What should I consider as I prepare my comments? 1. Submitting CBI Clearly mark the part or all of the information tha t you claim to be CBI. For CBI information in a disk or C D-ROM that you mail to the EPA, mark the outside of the disk o r CD-ROM as CBI and then identify electronically within the dis k or CD-ROM the specific information that is claimed as CBI. In addition to one complete version of the comment that includes i nformation claimed as CBI, a copy of the comment that does not contain the

information claimed as CBI must be submitted for in clusion in the public docket. Information marked as CBI will n ot be disclosed except in accordance with procedures set forth in 40 CFR part 2.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 27 of 324 Do not submit information that you consider to be C BI or otherwise protected through http://www.regulations. gov or email.

Send or deliver information identified as CBI to on ly the following address: OAQPS Document Control Officer ( Room C404- 02), U.S. EPA, Research Triangle Park, NC 27711, At tention Docket ID No. EPA-HQ-OAR-2014-0451. If you have any questions about CBI or the procedur es for claiming CBI, please consult the person identified in the FOR

FURTHER INFORMATION CONTACT section.

2. Docket

The docket number for the Emission Guidelines and Compliance Times for Municipal Solid Waste Landfill s (proposed 40 CFR part 60, subpart Cf) is Docket ID No. EPA-HQ -OAR-2014- 0451. Docket ID No. A-88-09 for related 40 CFR part 60, subparts WWW and Cc contains supporting information. C. Where can I get a copy of this document and othe r related

information? World Wide Web (WWW). In addition to being availabl e in the docket, an electronic copy of the proposed Emission Guidelines is available on the Technology Transfer Network (TT N) Web site. Following signature, the EPA will post a copy of pr oposed 40 CFR part 60, subpart Cf on the TTN’s policy and guidanc e page for newly proposed or promulgated rules at http://www.epa.gov/ttnatw01/landfill/landflpg.html. The TTN***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 28 of 324 provides information and technology exchange in var ious areas of air pollution control. III. Background The Emission Guidelines for MSW landfills were prom ulgated on March 12, 1996 and subsequently amended on June 16, 1998, February 24, 1999, and April 10, 2000 to make techn ical corrections and clarifications. Amendments were pro posed on May 23, 2002 and September 8, 2006 to address implement ation issues, but those amendments were never finalized. On July 17, 2014 the

EPA issued an ANPRM for the MSW landfills Emission Guidelines (79 FR 41772). The purpose of that action was to re quest public input on controls and practices that could further reduce emissions from existing MSW landfills and to evalua te that input to determine if changes to the Emission Guidelines were appropriate. On July 17, 2014 the EPA issued a conc urrent proposal for revised NSPS for new MSW landfills (79 FR 41796). In this action, the EPA is proposing a review of an d certain changes to the Emission Guidelines to build on prog ress to date to (1) achieve additional reductions in emissions o f LFG and its components, (2) account for changes in size, owners hip and age of landfills and trends in GCCS installations, as r eflected in new data, (3) provide new options for demonstrating compliance, and (4) to complete efforts regarding unresolved implementation issues. The proposed approaches are consistent with the Methane***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 29 of 324 Strategy developed as part of the President’s Clima te Action

Plan. A. Landfill Gas Emissions and Climate Change In June 2013, President Obama issued a Climate Acti on Plan that directed federal agencies to focus on “assessi ng current emissions data, addressing data gaps, identifying t echnologies and best practices for reducing emissions, and iden tifying existing authorities and incentive-based opportunit ies to reduce

methane emissions.” 4 Methane is a potent greenhouse gas (GHG) that is 28-36 times greater than carbon dioxide (CO 2 ) and has an atmospheric life of about 12 years 5 . Because of methane’s potency as a GHG and its atmospheric life, reducing methane emissions is one of the best ways to achieve near-term beneficia l impact in mitigating global climate change. The “Climate Action Plan: Strategy to Reduce Methan e Emissions” 6 (the Methane Strategy) was released in March 2014. The strategy recognized the methane reductions achi eved through

4 Executive Office of the President, “The President’ s Climate Action Plan” June 2013. https://www.whitehouse.gov/sites/default/files/imag e/president27sclimateactio nplan.pdf 5 The IPCC updates GWP estimates with each new asses sment report, and in the latest assessment report, AR5, the latest estimate of the methane GWP ranged from 28-36, compared to a GWP of 25 in AR4. The imp acts analysis in this proposal is based on AR4 instead of AR5 (i.e., a GW P of 25). 6 Executive Office of the President, “Climate Action Plan Strategy to Reduce Methane, March 2014. https://www.whitehouse.gov/sites/default/files/stra tegy_to_reduce_methane_emi ssions_2014-03-28_final.pdf***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 30 of 324 the EPA’s regulatory and voluntary programs to date . It also directed the EPA to continue to pursue emission red uctions through regulatory updates and to encourage LFG ene rgy recovery through voluntary programs. The EPA recognized the climate benefits associated with reducing methane emissions from landfills nearly 25 years ago. The 1991 NSPS Background Information Document 7 asserted that the

reduction of methane emissions from MSW landfills w as one of many options available to reduce global warming. Th e NSPS for MSW landfills, promulgated in 1996, also recognizedthe climate co-benefits of controlling methane (61 FR 9917, Mar ch 12, 1996). The review and proposed revision of the MSW landfil ls Emission Guidelines explores additional opportunities to ach ieve methane reductions while acknowledging historical agency pe rspectives and research on climate, a charge from the Presiden t’s Climate Action Plan, the Methane Strategy, and improvements in the science surrounding GHG emissions. Landfill gas is a collection of air pollutants, inc luding methane and NMOC. Landfill gas is typically compose d of 50- percent methane, 50-percent CO 2 , and less than 1-percent NMOC by volume. The NMOC portion of landfill gas can contai n various

7 Air Emissions from Municipal Solid Waste Landfills -Background Information for Proposed Standards and Guidelines, U.S. EPA (EP A–450/3–90–011a) (NTIS PB 91–197061) page 2–15.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 31 of 324 organic HAP and VOC. When the Emission Guidelines a nd NSPS were promulgated in 1996, NMOC was selected as a surroga te for MSW landfill gas emissions because NMOC contains the ai r pollutants

that at that time were of most pose more concern due to their adverse effects on health and welfare. Today, methane’s effects on climate change are also considered importantther e is a greater emphasis on methane emissions because of me thane’s effects on climate change . In 2012, methane emissions from MSW landfills represented 15.3 percent of total U.S. me thane emissions and 1.5 percent of total U.S. GHG emissio ns 8 . In 2013, landfills continued to be the third largest source of humanrelated methane emissions among stationary source c ategories in the U.S., representing 18.0 percent of total methan e emissions 9 and 1.7 percent of all GHG emissions (in CO 2 e) in the U.S. 10 For

these reasons and because additional emissions redu ctions can be achieved at a reasonable cost, the EPA is proposing changes to the Emission Guidelines that are based on reducing the NMOC and methane components of LFG.

B. What are the health and welfare effects of landf ill gas

emissions?

8 Total U.S. methane emissions were 636Tg CO 2 e in 2013. U.S. EPA “Inventory of U.S. Greenhouse Gas Emissions and Sinks: 1990–2013. ” Available at http://www.epa.gov/climatechange/ghgemissions/usinv entoryreport.html. 9 Ibid, Page ES-14.

10 Ibid, Table ES-2. Commented [A2]: OMB General Comment #11: Reviewer recommends editing the sentence on page 29 EG about NMOC containing air pollutants that pose more concern due to adverse effects on health and welfare. Since this rule focuses on greenhouse gas and aligns with the Climate Action Plan, it seems odd to call methane less concerning. EPA Response : See redline edits***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 32 of 324 1. Health Impacts of VOC and Various Organic HAP VOC emissions are precursors to both PM 2.5 and ozone formation. As documented in previous analyses (U.S. EPA, 2006 11 , 2010 12 , and 2014 13 ), exposure to PM 2.5 and ozone is associated with significant public health effects. PM 2.5 is associated with health effects, including premature mortality for a dults and infants, cardiovascular morbidity such as heart att acks, and respiratory morbidity such as asthma attacks, acute bronchitis, hospital admissions and emergency room visits, work loss days, restricted activity days and respiratory symptoms, as well as welfare impacts such as visibility impairment. 14 Ozone is associated with health effects, including hospital and emergency department visits, school loss days and premature m ortality, as well as ecological effects (e.g., injury to vegetat ion and

11 U.S. EPA. RIA. National Ambient Air Quality Standar ds for Particulate Matter, Chapter 5. Office of Air Quality Planning a nd Standards, Research Triangle Park, NC. October 2006. Available on the I nternet at http://www.epa.gov/ttn/ecas/regdata/RIAs/Chapter%20 5--Benefits.pdf. 12 U.S. EPA. RIA. National Ambient Air Quality Standa rds for Ozone. Office of Air Quality Planning and Standards, Research Triang le Park, NC. January 2010. Available on the Internet at http://www.epa.gov/ttn /ecas/regdata/RIAs/s1- supplemental_analysis_full.pdf. 13 U.S. EPA. RIA. National Ambient Air Quality Standa rds for Ozone. Office of Air Quality Planning and Standards, Research Triang le Park, NC. December 2014. Available on the Internet at http://www.epa.gov/ttnecas1/regdata/RIAs/20141125ri a.pdf. 14 U.S. EPA. Integrated Science Assessment for Partic ulate Matter (Final Report). EPA-600-R-08-139F. National Center for Env ironmental Assessment—RTP Division. December 2009. Available at http://cfpub.epa.gov/ncea/cfm/recordisplay.cfm?deid =216546.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 33 of 324 climate change). 15 Nearly 30 organic HAP have been identified in uncontrolled LFG, including benzene, toluene, ethyl benzene, and vinyl chloride. 16 Benzene is a known human carcinogen. 2. Climate Impacts of Methane Emissions In addition to the improvements in air quality and resulting benefits to human health and the non-clim ate welfare effects discussed above, reducing emissions from la ndfills is expected to result in climate co-benefits due to re ductions of the methane component of LFG. Methane is a potent G HG with a global warming potential (GWP) 28-36 times greater than CO 2 , which accounts for methane’s stronger absorption of infrared radiation per ton in the atmosphere, but also its s horter lifetime (on the order of 12 years compared to cent uries or

millennia for CO 2 ). 17,18 According to the Intergovernmental Panel

15 U.S. EPA. Air Quality Criteria for Ozone and Relat ed Photochemical Oxidants (Final). EPA/600/R-05/004aF-cF. Washington, DC: U.S . EPA. February 2006. Available on the Internet at http://cfpub.epa.gov/ncea/CFM/recordisplay.cfm?deid =149923. 16 U.S. EPA. 1998. Office of Air and Radiation, Offic e of Air Quality Planning and Standards. “Compilation of Air Pollutant Emissi on Factors, Fifth Edition, Volume I: Stationary Point and Area Sources, Chapte r 2: Solid Waste Disposal, Section 2.4: Municipal Solid Waste Landfills”. Avai lable at: http://www.epa.gov/ttn/chief/ap42/ch02/final/c02s04 .pdf. 17 IPCC, 2013: Climate Change 2013: The Physical Science Basis. Co ntribution of Working Group I to the Fifth Assessment Report o f the Intergovernmental Panel on Climate Change[Stocker, T.F., D. Qin, G.-K. Plattner, M. Tignor, S.K. Allen, J. Boschung, A. Nauels, Y. Xia, V. Bex and P.M. Midgley (eds.)]. Cambridge University Press, Cambridge, United Kingd om and New York, NY, USA. 18 Note that this proposal uses a GWP value for metha ne of 25 for CO 2 equivalency calculations, consistent with the GHG e missions inventories and the IPCC Fourth Assessment Report.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 34 of 324 on Climate Change (IPCC) 5 th Assessment Report, methane is the second leading long-lived climate forcer after CO 2 globally. 19 In 2009, based on a large body of robust and compel ling scientific evidence, the EPA Administrator issued t he Endangerment Finding under CAA section 202(a)(1). 20 In the Endangerment Finding, the Administrator found that the current, elevated concentrations of GHGs in the atmosphere—a lready at levels unprecedented in human history—may reasonabl y be anticipated to endanger public health and welfare o f current and future generations in the U.S. We summarize these a dverse effects on public health and welfare briefly here. 3. Public Health Impacts Detailed in the 2009 Endan germent Finding The 2009 Endangerment Finding documented that clima te change caused by human emissions of GHGs threatens the health of AmericansClimate change caused by human emissions o f GHGs threatens the health of Americans in multiple ways . By raising average temperatures, climate change increases the likelihood of heat waves, which are associated with increased dea ths and

19 IPCC, 2013: Climate Change 2013: The Physical Science Basis. Co ntribution of Working Group I to the Fifth Assessment Report o f the Intergovernmental Panel on Climate Change[Stocker, T.F., D. Qin, G.-K. Plattner, M. Tignor, S.K. Allen, J. Boschung, A. Nauels, Y. Xia, V. Bex and P.M. Midgley (eds.)]. Cambridge University Press, Cambridge, United Kingd om and New York, NY, USA. 19 “Endangerment and Cause or Contribute Findings for Greenhouse Gases Under 20 “Endangerment and Cause or Contribute Findings for Greenhouse Gases Under Section 202(a) of the Clean Air Act,” 74 Fed. Reg. 66,496 (Dec. 15, 2009) (“Endangerment Finding”). Commented [A3]: Response to OMB Comments (Typographical comments #1, 2, 5). EPA notes that pages 33-35 are a summary of the 2009 Endangerment Finding (which itself summarizes the assessment literature), and therefore inserting citations in the middle of the summary would not be appropriate. The statements from pages 35-50 reference in text the assessments (NCA3, NRC, or IPCC) from which they were taken. EPA has updated the first sentence of this section to make clear the information comes from the Endangerment Finding.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 35 of 324 illnesses. While climate change also increases the likelihood of reductions in cold-related mortality, evidence indi cates that the increases in heat mortality will be larger than the decreases in cold mortality in the United States. C ompared to a future without climate change, climate change is ex pected to increase ozone pollution over broad areas of the U. S., including in the largest metropolitan areas with the worst oz one problems, and thereby increase the risk of morbidity and mort ality. Climate change is also expected to cause more inten se hurricanes and more frequent and intense storms and heavy prec ipitation, with impacts on other areas of public health, such as the potential for increased deaths, injuries, infectiou s and waterborne diseases, and stress-related disorders. Children, the elderly, and the poor are among the most vulnerable to these

climate-related health effects. 4. Public Welfare Impacts Detailed in the 2009 Enda ngerment Finding The 2009 Endangerment Finding documented that clima te change impacts touch nearly every aspect of public welfareClimate change impacts touch nearly every as pect of public welfare . Among the multiple threats caused by human emissions of GHGs, climate changes are expected to place large areas of the country at serious risk of reduced wat er supplies, increased water pollution, and increased occurrence of extreme Commented [A4]: Response to OMB Comments (Typographical comments #1, 2, 5). EPA notes that pages 33-35 are a summary of the 2009 Endangerment Finding (which itself summarizes the assessment literature), and therefore inserting citations in the middle of the summary would not be appropriate. The statements from pages 35-50 reference in text the assessments (NCA3, NRC, or IPCC) from which they were taken. EPA has updated the first sentence of this section to make clear the information comes from the Endangerment Finding.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 36 of 324 events such as floods and droughts. Coastal areas a re expected to face a multitude of increased risks, particularl y from rising sea level and increases in the severity of storms. These communities face storm and flooding damage to prope rty, or even loss of land due to inundation, erosion, wetland su bmergence and

habitat loss. Impacts of climate change on public welfare also in clude threats to social and ecosystem services. Climate c hange is expected to result in an increase in peak electrici ty demand, Extreme weather from climate change threatens energ y, transportation, and water resource infrastructure. Climate change may also exacerbate ongoing environmental pr essures in certain settlements, particularly in Alaskan indige nous communities, and is very likely to fundamentally re arrange U.S. ecosystems over the 21st century. Though some benef its may balance adverse effects on agriculture and forestry in the next few decades, the body of evidence points towards in creasing risks of net adverse impacts on U.S. food productio n, agriculture and forest productivity as temperature continues to rise. These impacts are global and may exacerbate p roblems outside the U.S. that raise humanitarian, trade, an d national security issues for the U.S.

5. New Scientific Assessments***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 37 of 324 Since the 2009 administrative record concerning the Endangerment Finding closed following the EPA’s 201 0 Reconsideration Denial, the climate has continued t o change, with new records being set for a number of climate indicators such as global average surface temperatures, Arctic sea ice retreat, CO 2 concentrations, and sea level rise. Additionally, a number of major, scientific assessments have been r eleased that improve understanding of the climate system and str engthen the case that GHGs endanger public health and welfare b oth for current and future generations. These assessments, from the Intergovernmental Panel on Climate Change (IPCC), t he U.S. Global Change Research Program (USGCRP), and the Na tional Research Council of the National Academies (NRC), i nclude: IPCC’s 2012 Special Report on Managing the Risks of Extreme Events and Disasters to Advance Climate Change Adap tation (SREX) and the 2013-2014 Fifth Assessment Report (AR5), US GCRP’s 2014 National Climate Assessment, Climate Change Impacts in the United States (NCA3), and the NRC’s 2010 Ocean Acid ification: A National Strategy to Meet the Challenges of a Chang ing Ocean (Ocean Acidification), 2011 Report on Climate Stabi lization Targets: Emissions, Concentrations, and Impacts ove r Decades to Millennia (Climate Stabilization Targets), 2011 Nat ional Security Implications for U.S. Naval Forces (Nation al Security Implications), 2011 Understanding Earth’s Deep Past : Lessons for***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 38 of 324 Our Climate Future (Understanding Earth’s Deep Past ), 2012 Sea Level Rise for the Coasts of California, Oregon, an d Washington: Past, Present, and Future, 2012 Climate and Social Stress: Implications for Security Analysis (Climate and Soc ial Stress), and 2013 Abrupt Impacts of Climate Change (Abrupt I mpacts)

assessments. The EPA has carefully reviewed these recent assessm ents in keeping with the same approach outlined in Section VIII.A of the 2009 Endangerment Finding, which was to rely primar ily upon the major assessments by the USGCRP, IPCC, and the NRC to provide

the technical and scientific information to inform the Administrator’s judgment regarding the question of whether GHGs endanger public health and welfare. These assessmen ts addressed the scientific issues that the EPA was required to examine were comprehensive in their coverage of the GHG and clim ate change issues, and underwent rigorous and exacting peer re view by the expert community, as well as rigorous levels of U.S . government

review. The findings of the recent scientific assessments c onfirm and strengthen the conclusion that GHGs endanger pu blic health,

now and in the future. The NCA3 indicates that huma n health in the United States will be impacted by “increased ex treme weather events, wildfire, decreased air quality, threats to mental health, and illnesses transmitted by food, water, a nd disease-***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 39 of 324 carriers such as mosquitoes and ticks.” The most re cent assessments now have greater confidence that climat e change will influence production of pollen that exacerbates ast hma and other allergic respiratory diseases such as allergic rhin itis, as well as effects on conjunctivitis and dermatitis. Both t he NCA3 and the IPCC AR5 found that increasing temperature has lengthened the allergenic pollen season for ragweed, and that increased CO 2 by itself can elevate production of plant-based all ergens. The NCA3 also finds that climate change, in additio n to chronic stresses such as extreme poverty, is negati vely affecting indigenous peoples’ health in the United States through impacts such as reduced access to tradition al foods, decreased water quality, and increasing exposure to health and safety hazards. The IPCC AR5 finds that climate cha nge-induced warming in the Arctic and resultant changes in envi ronment (e.g., permafrost thaw, effects on traditional food sources) have significant impacts, observed now and projecte d, on the health and well-being of Arctic residents, especial ly indigenous peoples. Small, remote, predominantly-indigenous co mmunities are especially vulnerable given their “strong dependenc e on the environment for food, culture, and way of life; the ir political and economic marginalization; existing social, heal th, and poverty disparities; as well as their frequent clos e proximity***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 40 of 324 to exposed locations along ocean, lake, or river sh orelines.” 21 In addition, increasing temperatures and loss of Ar ctic sea ice increases the risk of drowning for those engaged in traditional hunting and fishing. The NCA3 concludes that children’s unique physiolog y and developing bodies contribute to making them particu larly vulnerable to climate change. Impacts on children a re expected from heat waves, air pollution, infectious and wate rborne illnesses, and mental health effects resulting from extreme weather events. The IPCC AR5 indicates that childre n are among those especially susceptible to most allergic disea ses, as well as health effects associated with heat waves, storm s, and

floods. The IPCC finds that additional health conce rns may arise in low income households, especially those with chi ldren, if climate change reduces food availability and increa ses prices, leading to food insecurity within households.

Both the NCA3 and IPCC AR5 conclude that climate ch ange will increase health risks facing the elderly. Olde r people are at much higher risk of mortality during extreme hea t events. Pre-existing health conditions also make older adul ts

21 IPCC, 2014: Climate Change 2014: Impacts, Adaptation, and Vulne rability. Part B: Regional Aspects . Contribution of Working Group II to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change [Barros, V.R., C.B. Field, D.J. Dokken, M.D. Mastrandrea, K. J. Mach, T.E. Bilir, M. Chatterjee, K.L. Ebi, Y.O. Estrada, R.C. Genova, B. Girma, E.S. Kissel, A.N. Levy, S. MacCracken, P.R. Mastrandrea, and L.L. Whi te (eds.)]. Cambridge University Press, Cambridge, p. 1581.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 41 of 324 susceptible to cardiac and respiratory impacts of a ir pollution and to more severe consequences from infectious andwaterborne diseases. Limited mobility among older adults can a lso increase

health risks associated with extreme weather and fl oods. The new assessments also confirm and strengthen the conclusion that GHGs endanger public welfare, and e mphasize the urgency of reducing GHG emissions due to their proj ections that show GHG concentrations climbing to ever-increasing levels in the absence of mitigation. The NRC assessment Under standing Earth’s Deep Past projected that, without a reducti on in emissions, CO 2 concentrations by the end of the century would increase to levels that the Earth has not experienc ed for more than 30 million years. 22 In fact, that assessment stated that “the magnitude and rate of the present greenhouse g as increase place the climate system in what could be one of th e most severe increases in radiative forcing of the global climat e system in Earth history.” 23 Because of these unprecedented changes, several assessments state that we may be approaching critic al, poorly

understood thresholds: as stated in the NRC assessm ent Understanding Earth’s Deep Past, “As Earth continue s to warm, it may be approaching a critical climate threshold bey ond which rapid and potentially permanent—at least on a human timescale—

22 National Research Council, Understanding Earth’s D eep Past, p. 1. 23 Id., p.138.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 42 of 324 changes not anticipated by climate models tuned to modern conditions may occur.” Moreover, due to the time la gs inherent in the Earth’s climate, the NRC Climate Stabilizati on Targets assessment notes that the full warming from increas ed GHG concentrations will not be fully realized for sever al centuries, underscoring that emission activities today carry w ith them

climate commitments far into the future. Future temperature changes will depend on what emis sion path the world follows. In its high emission scenar io, the IPCC AR5 projects that global temperatures by the end of the century will likely be 2.6 °C to 4.8 °C (4.7 to 8.6 °F) war mer than today. Temperatures on land and in northern latitud es will likely warm even faster than the global average. Ho wever, according to the NCA3, significant reductions in em issions would lead to noticeably less future warming beyond mid-c entury, and therefore less impact to public health and welfare. While rainfall may see only small globally and annu ally averaged changes, there are expected to be substant ial shifts in where and when that precipitation falls. According to the NCA3, regions closer to the poles will see more precipita tion, while the dry subtropics are expected to expand (colloqui ally, this has been summarized as wet areas getting wetter and dry regions getting drier). In particular, the NCA3 notes that the western U.S., and especially the Southwest, is expected to become drier.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 43 of 324 This projection is consistent with the recent obser ved drought trend in the West. At the time of publication of th e NCA, even before the last 2 years of extreme drought in Calif ornia, tree ring data was already indicating that the region mi ght be experiencing its driest period in 800 years. Simila rly, the NCA3 projects that heavy downpours are expected to incre ase in many regions, with precipitation events in general becom ing less frequent but more intense. This trend has already b een observed in regions such as the Midwest, Northeast, and uppe r Great Plains. Meanwhile, the NRC Climate Stabilization Ta rgets assessment found that the area burned by wildfire i s expected to grow by 2 to 4 times for 1 °C (1.8 °F) of warming. For 3 °C of warming, the assessment found that nine out of 10 s ummers would be warmer than all but the 5 percent of warmest summers today, leading to increased frequency, duration, and inten sity of heat waves. Extrapolations by the NCA also indicate that Arctic sea ice in summer may essentially disappear by mid-cent ury. Retreating snow and ice, and emissions of carbon di oxide and methane released from thawing permafrost, will also amplify future warming. Since the 2009 Endangerment Finding, the USGCRP NCA 3 and multiple NRC assessments have projected future rate s of sea level rise that are 40 percent larger to more than twice as large as the previous estimates from the 2007 IPCC 4 th Assessment***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 44 of 324 Report due in part to improved understanding of the future rate

of melt of the Antarctic and Greenland ice sheets. The NRC Sea Level Rise assessment projects a global sea level r ise of 0.5 to 1.4 meters (1.6 to 4.6 feet) by 2100, the NRC Natio nal Security Implications assessment suggests that “the Departme nt of the Navy should expect roughly 0.4 to 2 meters (1.3 to 6.6 feet) global average sea-level rise by 2100,” 24 and the NRC Climate Stabilization Targets assessment states that an inc rease of 3°C will lead to a sea level rise of 0.5 to 1 meter (1. 6 to 3.3 feet) by 2100. These assessments continue to recogn ize that there is uncertainty inherent in accounting for ice sheet processes. Additionally, local sea level rise can d iffer from the global total depending on various factors: the east coast of the U.S. in particular is expected to see higher ra tes of sea level rise than the global average. For comparison, the NCA3

states that “five million Americans and hundreds of billions of dollars of property are located in areas that are l ess than four feet above the local high-tide level,” and the NCA3 finds that “[c]oastal infrastructure, including roads, rail li nes, energy infrastructure, airports, port facilities, and mili tary bases, are increasingly at risk from sea level rise and da maging storm

24 NRC, 2011: National Security Implications of Climate Change fo r U.S. Naval Forces . The National Academies Press, p. 28.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 45 of 324 surges.” 25 Also, because of the inertia of the oceans, sea le vel

rise will continue for centuries after GHG concentr ations have stabilized (though more slowly than it would have o therwise). Additionally, there is a threshold temperature abov e which the

Greenland ice sheet will be committed to inevitable melting: according to the NCA, some recent research has sugg ested that even present day carbon dioxide levels could be suf ficient to

exceed that threshold. In general, climate change impacts are expected to be unevenly distributed across different regions of th e United States and have a greater impact on certain populat ions, such as indigenous peoples and the poor. The NCA3 finds cli mate change impacts such as the rapid pace of temperature rise, coastal

erosion and inundation related to sea level rise an d storms, ice and snow melt, and permafrost thaw are affecting in digenous people in the United States. Particularly in Alaska , critical

infrastructure and traditional livelihoods are thre atened by climate change and, “[i]n parts of Alaska, Louisian a, the Pacific Islands, and other coastal locations, clima te change impacts (through erosion and inundation) are so sev ere that some communities are already relocating from historical homelands to

25 Melillo, Jerry M., Terese (T.C.) Richmond, and Gar y W. Yohe, Eds., 2014: Climate Change Impacts in the United States: The Th ird National Climate Assessment. U.S. Global Change Research Program, p. 9.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 46 of 324

which their traditions and cultural identities are tied.” 26 The IPCC AR5 notes, “Climate-related hazards exacerbate other stressors, often with negative outcomes for livelih oods, especially for people living in poverty (high confi dence). Climate-related hazards affect poor people’s lives directly through impacts on livelihoods, reductions in crop yields, or destruction of homes and indirectly through, for ex ample, increased food prices and food insecurity.” 27 Events outside the United States, as also pointed o ut in the 2009 Endangerment Finding, will also have relev ant consequences. The NRC Climate and Social Stress ass essment concluded that it is prudent to expect that some cl imate events “will produce consequences that exceed the capacity of the affected societies or global systems to manage and that have global security implications serious enough to comp el international response.” The NRC National Security Implications assessment recommends preparing for increased needs for humanitarian aid; responding to the effects of clim ate change in geopolitical hotspots, including possible mass migr ations; and

26 Melillo, Jerry M., Terese (T.C.) Richmond, and Gar y W. Yohe, Eds., 2014: Climate Change Impacts in the United States: The Th ird National Climate Assessment. U.S. Global Change Research Program, p. 17. 27 IPCC, 2014: Climate Change 2014: Impacts, Adaptation, and Vulne rability. Part A: Global and Sectoral Aspects. Contribution of Working Group II to the Fifth Assessment Report of the Intergovernmental Pa nel on Climate Change [Field, C.B., V.R. Barros, D.J. Dokken, K.J. Mach, M.D. Mastrandrea, T.E. Bilir, M. Chatterjee, K.L. Ebi, Y.O. Estrada, R.C. Genova, B. Girma, E.S. Kissel, A.N. Levy, S. MacCracken, P.R. Mastrandrea, and L.L. White (eds.)]. Cambridge University Press, p. 796.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 47 of 324 addressing changing security needs in the Arctic as sea ice

retreats. In addition to future impacts, the NCA3 emphasizes that climate change driven by human emissions of GHGs is already happening now and it is happening in the United Sta tes. According to the IPCC AR5 and the NCA3, there are a number of climate-related changes that have been observed rec ently, and these changes are projected to accelerate in the fu ture. The planet warmed about 0.85 °C (1.5 °F) from 1880 to 2 012. It is extremely likely (>95 percent probability) that hum an influence was the dominant cause of the observed warming sinc e the mid-20 th century, and likely (>66 percent probability) that human influence has more than doubled the probability of occurrence of

heat waves in some locations. In the Northern Hemis phere, the last 30 years were likely the warmest 30 year perio d of the last 1,400 years. U.S. average temperatures have similar ly increased by 1.3 to 1.9 degrees F since 1895, with most of th at increase occurring since 1970. Global sea levels rose 0.19 m (7.5 inches) from 1901 to 2010. Contributing to this rise was th e warming of the oceans and melting of land ice. It is likely th at 275 gigatons per year of ice melted from land glaciers (not including ice sheets) since 1993, and that the rate of loss of

ice from the Greenland and Antarctic ice sheets inc reased substantially in recent years, to 215 gigatons per year and 147***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 48 of 324 gigatons per year respectively since 2002. For cont ext, 360 gigatons of ice melt is sufficient to cause global sea levels to rise 1 millimeter (mm). Annual mean Arctic sea ice has been declining at 3.5 to 4.1 percent per decade, and Nor thern Hemisphere snow cover extent has decreased at about 1.6 percent per decade for March and 11.7 percent per decade fo r June. Permafrost temperatures have increased in most regi ons since the 1980s, by up to 3 °C (5.4 °F) in parts of Northern Alaska. Winter storm frequency and intensity have both incr eased in the Northern Hemisphere. The NCA3 states that the incre ases in the severity or frequency of some types of extreme weat her and climate events in recent decades can affect energy production and delivery, causing supply disruptions, and compr omise other essential infrastructure such as water and transpor tation systems. In addition to the changes documented in the assess ment literature, there have been other climate milestone s of note. According to the IPCC, methane concentrations in 20 11 were about 1,803 parts per billion, 150 percent higher than co ncentrations were in 1750. After a few years of nearly stable co ncentrations from 1999 to 2006, methane concentrations have resu med increasing at about 5 parts per billion per year. C oncentrations today are likely higher than they have been for at least the past 800,000 years. Arctic sea ice has continued to decline,***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 49 of 324 with September of 2012 marking a new record low in terms of Arctic sea ice extent, 40 percent below the 1979-20 00 median.

Sea level has continued to rise at a rate of 3.2 mm per year (1.3 inches/decade) since satellite observations st arted in 1993, more than twice the average rate of rise in t he 20 th century prior to 1993. 28 And 2014 was the warmest year globally in the modern global surface temperature record, go ing back to 1880; this now means 19 of the 20 warmest years hav e occurred in the past 20 years, and except for 1998, the 10 warm est years on record have occurred since 2002. 29 The first months of 2015 have

also been some of the warmest on record. These assessments and observed changes make it clea r that reducing emissions of GHGs across the globe is nece ssary in order to avoid the worst impacts of climate change, and underscore the urgency of reducing emissions now. T he NRC

Committee on America’s Climate Choices listed a num ber of reasons “why it is imprudent to delay actions that at least begin the process of substantially reducing emissio ns.” 30 For example:

• The faster emissions are reduced, the lower the ris ks posed by climate change. Delays in reducing emissio ns

28 Blunden, J., and D. S. Arndt, Eds., 2014: State of the Climate in 2013. Bull. Amer. Meteor. Soc., 95 (7), S1-S238. 29 http://www.ncdc.noaa.gov/sotc/global/2014/13. 30 NRC, 2011: America’s Climate Choices , The National Academies Press.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 50 of 324 could commit the planet to a wide range of adverse impacts, especially if the sensitivity of the clima te to GHGs is on the higher end of the estimated range

.

• Waiting for unacceptable impacts to occur before taking action is imprudent because the effects of G HG emissions do not fully manifest themselves for deca des and, once manifest, many of these changes will pers ist for hundreds or even thousands of years. In the committee’s judgment, the risks associated w ith doing business as usual are a much greater concern than the risks associated with engaging in strong response e fforts. Methane is a precursor to ground-level ozone, a hea lthharmful air pollutant. Additionally, ozone is a sho rt-lived climate forcer that contributes to global warming. In remote areas, methane is a dominant precursor to troposphe ric ozone

formation. 31 Approximately 50 percent of the global annual mean ozone increase since preindustrial times is believe d to be due to anthropogenic methane. 32 Projections of future emissions also

31 U.S. EPA. 2013. “Integrated Science Assessment for Ozone and Related Photochemical Oxidants (Final Report).” EPA-600-R-1 0-076F. National Center for Environmental Assessment—RTP Division. Availabl e at http://www.epa.gov/ncea/isa/. 32 Myhre, G., D. Shindell, F.-M. Bréon, W. Collins, J . Fuglestvedt, J. Huang, D. Koch, J.-F. Lamarque, D. Lee, B. Mendoza, T. Nak ajima, A. Robock, G. Stephens, T. Takemura and H. Zhang, 2013: Anthropog enic and Natural Radiative Forcing. In: Climate Change 2013: The Physical Scie nce Basis. Contribution of Working Group I to the Fifth Assessment Report of t he Intergovernmental Panel on Climate Change [Stocker, T.F., D. Qin, G.-K. Pla ttner, M. Tignor, S.K. Allen, J. Boschung, A. Nauels, Y. Xia, V. Bex and P .M. Midgley (eds.)].***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 51 of 324 indicate that methane is likely to be a key contrib utor to ozone

concentrations in the future. 33 Unlike nitrogen oxide (NO X ) and VOC, which affect ozone concentrations regionally a nd at hourly time scales, methane emissions affect ozone concent rations globally and on decadal time scales given methane’s relatively long atmospheric lifetime compared to these other o zone

precursors. 34 Reducing methane emissions, therefore, may contribute to efforts to reduce global background o zone concentrations that contribute to the incidence of ozone-related

health effects. 35,36 These benefits are global and occur in both

urban and rural areas. C. What is EPA’s authority for reviewing the Emissi on Guidelines? The EPA is not statutorily obligated to conduct a r eview of the Emission Guidelines, but has the discretionary authority to do so when circumstances indicate that it is approp riate. The EPA has determined that it is appropriate to conduc t a review of and propose certain changes to the Emission Guideli nes due to changes in the size, ownership and age of landfills and the

Cambridge University Press, Cambridge, United Kingd om and New York, NY, USA. Pg. 680. 33 Ibid

. 34 Ibid

. 35 West, J.J., Fiore, A.M. 2005. “Management of tropo spheric ozone by reducing methane emissions.” Environ. Sci. Technol. 39:4685- 4691. 36 Anenberg, S.C., et al. 2009. “Intercontinental imp acts of ozone pollution on human mortality,” Environ. Sci. & Technol. 43: 6 482-6487.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 52 of 324 types of MSW landfills with gas collection systems installed since the Emission Guidelines were promulgated in 1 996 and the opportunities for significant reductions in methane and other pollutants at reasonable cost. The EPA compiled newinformation on MSW landfills through data collection efforts fo r a statutorily mandated review of the NSPS, public comments received on the NSPS proposal, and public comments received on

an ANPRM for a review of the Emission Guidelines. T his

information allowed the EPA to conduct an assessmen t of current practices, emissions and potential for additional e mission reductions. Information received in response to thi s proposed

rule will allow EPA to further refine that assessme nt. D. What is the purpose and scope of this action? The purpose of this action is to (1) present the re sults of EPA’s initial review of the Emission Guidelines, (2 ) propose and

take comment on revisions to the Emission Guideline s based on that review, and (3) propose a resolution or provid e clarification regarding implementation issues that were addressed in prior proposed amendments published on May 23, 2002 (67 FR 36475) and September 8, 2006 (71 FR 53271) a s they apply to existing sources. The proposed revisions appear in the proposed 40 CFR part 60, subpart Cf. 37 Although the EPA is not

37 Rather than merely updating 40 CFR part 60, subpar t Cc, the existing emissions guidelines, the EPA has determined that t he most appropriate way to***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 53 of 324 required to respond to comments received on the Jul y 17, 2014 ANPRM (79 FR 41772) for the MSW landfills Emission Guidelines or comments it received on the concurrent proposal for revised NSPS for new MSW landfills in this notice, the EPA is su mmarizing several comments it received to provide a framework and support

the rationale for today’sthe proposed revisions to the Emission

Guidelines. E. How would the proposed changes in applicability affect sources currently subject to subparts Cc and WWW? Landfills currently subject to 40 CFR part 60, subp arts Cc and WWW would be considered “existing” and would ul timately be affected by any changes to the Emission Guidelines resulting from this review. Any source for which construction , modification, or reconstruction commenced on or bef ore July 17, 2014, the date of proposal of new subpart XXX, is a n existing source. Under section 111, a source is either new, i.e., construction, modification, or reconstruction comme nced after a proposed NSPS is published in the Federal Register (CAA section 111(a)(1)) or existing, i.e., any source other than a new source (CAA section 111(a)(6)). Since the revised Emission Guidelines apply to existing sources, any source that is not s ubject to new

proceed is to establish a new subpart that includes both the verbatim restatement of certain provisions in the existing e mission guidelines and proposed revisions to, or the addition of, other pr ovisions.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 54 of 324 subpart XXX will be subject to the revised Emission Guidelines. Consistent with the general approach evinced by sec tion 111, sources currently subject to subpart WWW would needto continue to comply with the requirements in that rule unless and until they become subject to more stringent requirements in the revised Emission Guidelines as implemented through a revised state or federal plan. The current Emission Guideli nes, subpart Cc, refer to subpart WWW for their substantive requ irements. That is, the requirements regarding the installatio n and operation of a well-designed and well-operated GCCS and compliance with the specified emission limits are t he same in both rules. Thus, if the EPA were to finalize its p roposal to

revise the Emission Guidelines to increase their st ringency, a landfill currently subject to 40 CFR part 60, subpa rt WWW would need to comply with the more stringent requirements in a revised state plan or federal plan implementing the revisedEmission Guidelines (40 CFR part 60, subpart Cf). States wit h designated facilities would be required to develop (or revise) and submit a state plan to the EPA within 9 months of promulgati on of any

revisions to the Emission Guidelines unless the EPA specifies a longer timeframe in promulgating those revisions (4 0 CFR 60.23). Any revisions to an existing state plan and any new ly adopted state plan must be established following the requir ements of 40 CFR part 60, subpart B (40 CFR 60.20 – 60. 29). Those***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 55 of 324 requirements include making the state plan publical ly available and providing the opportunity for public discussion

. Once the EPA receives a complete state plan or plan revision, and completes its review of that plan or plan revision, the EPA will propose the plan or plan rev ision for approval or disapproval. The EPA will approve or di sapprove the plan or plan revision no later than 4 months after the date the plan or plan revision was required to be submitted 40 CFR 60.27(b). The EPA will publish state plan approvals or disapprovals in the Federal Register and will inclu de an explanation of its decision. The EPA also intends t o revise the existing federal plan (40 CFR part 62, subpart GGG) to incorporate any changes and other requirements that result from

the EPA’s review of the Emission Guidelines. The re vised federal plan will apply in states that have either never su bmitted a state plan or not received approval of any necessar y revised state plan until such time as an initial state plan or revised state plan is approved. 38 Because many of the landfills currently subject to 40 CFR part 60, subparts Cc and WWW are closed, the EPA is proposing

38 Indian tribes may, but are not required to, seek a pproval for treatment in a manner similar to a state for purposes of develop ing a tribal implementation plan (TIP) implementing the emission guidelines. If a tribe obtains such approval and submits a proposed TIP, t he EPA will use the same criteria and follow the same procedure in approving that plan as it does with state plans. The federal plan will apply to all aff ected facilities located in Indian country unless and until EPA approves an applicable TIP.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 56 of 324

several items to minimize the burden ofon these closed landfills, as discussed in section VIII.A of this p reamble. F. Where in the CFR will these changes appear? The EPA is proposing to add a new subpart Cf to 40 CFR part 60, beginning at 40 CFR 60.30f. Subpart Cf would ap ply to landfills that have accepted waste after November 8 , 1987 and were constructed, reconstructed, or modified on or before July 17, 2014. Proposed subpart Cf in 40 CFR part 60 con tains a

revision to the NMOC emission threshold for landfil ls that are not closed and addresses technical and implementati on issues for all landfills subject to this subpart. IV. Summary of Proposed Changes Based on Review of the Emission

Guidelines The EPA is proposing several changes to the Emissio n Guidelines following its review of the Emission Gui delines and

the NSPS for MSW landfills. The EPA reviewed both l andfills regulations and considered the current technology, practices, and associated monitoring, recordkeeping, and repor ting requirements. The rationale for the following propo sed changes is presented in sections V through VIII of this pre amble. A. Control Technology Review 1. Best System of Emission Reduction The EPA has determined that a well-designed and wel l operated landfill GCCS with a control device capabl e of reducing Commented [A5]: OMB Typographical Comment 6: Reviewer recommends replacing the word “of” with “on” on page 54 EG in the sentence including “...several items to minimize the burden...” Response: Text has been edited.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 57 of 324 NMOC by 98 percent by weight continues to be the be st system of emission reduction (BSER) for controlling LFG emiss ions. Thus, there is no change to the fundamental means of cont rolling LFG: proposed 40 CFR part 60, subpart Cf requires landfi ll owners and operators to install a system to collect the LFG fr om the landfill and to route the collected gas to a combus tion device or treatment system. Landfill owners and operators must submit for approval a site-specific GCCS design plan prepa red by a professional engineer. The EPA is proposing 98 perc ent reduction of NMOC, expressed as a performance level (i.e., a rate-based standard or percent control), as the appropriate BS ER-based standard. Thus, 40 CFR part 60, subpart Cf requires combustion control devices to demonstrate 98 percent reduction by weight of NMOC or an outlet concentration of 20 parts per mil lion dry volume (ppmvd) of NMOC, as hexane. Enclosed combust ion devices have the option of reducing emissions to 20 ppmvd. The EPA carefully considered whether various emissi on reduction techniques and BMPs that could improve co llection and

control of LFG emissions should be considered a component of BSER. As explained in section V.A. of this document , the EPA has

concluded that the various emission reduction techn iques and BMPs should not be considered to be components of B SER and, therefore, is not proposing to require their use. T he EPA***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 58 of 324 believes that the techniques and BMPs can, however, be useful in minimizing emissions in appropriate circumstances. 2. Criteria for Installing and Expanding GCCS The EPA undertook an analysis of existing landfills to determine whether applying the existing 40 CFR part 60, subpart Cc and WWW size, emissions, and timing criteria for installing and operating a landfill GCCS to the population of existing MSW landfills remains the preferred approach to impleme nting BSER. Based on the analysis of the threshold and timing p arameters, the EPA is proposing to reduce the NMOC emission ra te threshold for installing the GCCS from 50 Mg/yr to 34 Mg/yr. There are no proposed changes regarding the size of landfill cov ered by the Emission Guidelines or the timing of installation a nd expansion: the requirements would continue to apply to landfil ls with a design capacity greater than 2.5 million Mg and 2.5 million cubic meters, landfill owners and operators would c ontinue to have 30 months to install and begin operating the G CCS upon the landfill exceeding the emission threshold and owner s, and operators would be required to expand the GCCS into new areas of the landfill within 5 years for active areas and wi thin 2 years for areas that are closed or at final grade. Howeve r, a landfill could potentially delay the requirement to install a GCCS through the use of emission reduction techniques an d BMPs in conjunction with Tier 4 monitoring. The rationale f or the change***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 59 of 324 to the NMOC emissions threshold is provided in sect ion V.B of this preamble and the rationale for Tier 4 is prese nted in section VII.A of this preamble. B. Proposed changes to Monitoring, Recordkeeping, a nd Reporting 1. Proposed Changes to Monitoring Surface Monitoring. The EPA proposes that all surfa ce penetrations at existing landfills must be monitore d. In proposed 40 CFR part 60, subpart Cf, landfills must monitor all cover penetrations and openings within the area of the landfill where waste has been placed and a gas collection sy stem is required to be in place and operating according to the operational standards in proposed 40 CFR part 60, s ubpart Cf. Specifically, landfill owners/operators must conduc t surface monitoring on a quarterly basis at 30-meter interva ls and where

visual observations indicate elevated concentration s of landfill gas, such as distressed vegetation and cracks or se eps in the cover and all cover penetrations. The EPA is also considering alternative surface mon itoring provisions for 40 CFR part 60, subpart Cf. The alte rnative provisions would reduce the walking pattern for con ducting surface monitoring from 30-meter (98 feet (ft)) int ervals to 25-

ft intervals. The alternative would also add a meth ane concentration limit of 25 ppm as determined by inte grated surface emissions monitoring, in addition to the in stantaneous***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 60 of 324 methane concentration limit of 500 ppm. This altern ative would also limit surface monitoring during windy conditio ns. Under the alternative, the landfill would have to take correc tive action if either the integrated or instantaneous limits we re exceeded. More information about this approach is provided in sections VI.A and X.B of this preamble. The EPA is also proposing an alternative site-speci fic

emission threshold determination based on surface e mission monitoring for when a landfill must install and ope rate a GCCS, as described in sections IV.C and VII.A, and when t o cap or remove a GCCS, as described in section VIII of this preamble. Wellhead Monitoring. The EPA proposes to remove the operational standards (i.e., the requirement to mee t operating limits) for temperature and nitrogen/oxygen at the wellheads and is thus removing the corresponding requirement to t ake corrective action for exceedances of these two para meters as discussed in section VI.B of this preamble. These a djustments to the wellhead monitoring parameters would apply to a ll landfills. Monthly monitoring of oxygen/nitrogen and temperatu re would still be required; however, fluctuations/variations in these parameters would no longer be required to be identi fied as exceedances in the annual reports. Instead, the lan dfill would maintain the records of this monthly monitoring on site and use the monitoring to inform any necessary adjustments to the GCCS***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 61 of 324 and make them available to the Administrator (EPA A dministrator or administrator of a state air pollution control a gency or his or her designee) upon request. Landfill owners and operators would continue to be required to operate their GCCS with negative pressure and in a manner that collects the most LFG and minimizes losses of LFG through the surface of the landfill. Landfills would also continue to be required to pre pare and submit to the regulating authority for approval a g as collection design plan, prepared by a professional engineer. 2. Proposed Changes to Recordkeeping and Reporting Update and Approval of Design Plan. We propose two criteria for when an affected source must update its design plan and submit it to the Administrator for approval. A revi sed design plan would be submitted on the following timeline: (1) Within 90 days of expanding operations to an area not coveredby the previously approved design plan; and (2) prior to i nstalling or expanding the gas collection system in a manner oth er than one described in a previously approved design plan. The EPA is also taking comment on potentially establishing a third- party design plan certification program, which could reduce the burden associated with EPA or state review and approval of sitespecific design plans and plan revisions, as discus sed in section X.E of this preamble.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 62 of 324 Submitting Corrective Action Timeline Requests. The EPA expects that eliminating the operational standards for oxygen/nitrogen and temperature will drastically re duce the number of requests for alternative timelines for ma king necessary corrections. However, landfills would sti ll be required to maintain negative pressure at the wellh ead to

demonstrate a sufficient extraction rate and would be required to take corrective action in the event that a negat ive pressure is not maintained. Therefore, proposed 40 CFR part 60, subpart Cf outlines the timeline for correcting positive pr essure. A

landfill must submit an alternative corrective acti on timeline request to the Administrator if the landfill cannot restore negative pressure within 15 calendar days of the in itial failure to maintain negative pressure and the landfill is u nable to (or does not plan to) expand the gas collection within 120 days of

the initial exceedance. Electronic Reporting. The EPA is proposing electron ic reporting of required performance test reports, NMO C emission rate reports, and annual reports. We also propose t hat industry should be required to maintain only electronic copi es of the records to satisfy federal recordkeeping requiremen ts. The proposed electronic submission and storage procedur es are discussed in detail in section VI.E of this preambl e.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 63 of 324 The proposal to submit performance test data electr onically to the EPA applies only to those performance tests conducted using test methods that are supported by the Electr onic Reporting Tool (ERT). A listing of the pollutants a nd test methods supported by the ERT is available at: http://www.epa.gov/ttn/chief/ert/index.html. When t he EPA adds new methods to the ERT, a notice will be sent out t hrough the Clearinghouse for Inventories and Emissions Factors (CHIEF) Listserv (http://www.epa.gov/ttn/chief/listserv.htm l#chief) and a notice of availability will be added to the ERT W eb site. You are encouraged to check the ERT Web site regularly for up-todate information on methods supported by the ERT.

C. Emission Threshold Determinations The EPA is proposing an alternative site-specific e mission

threshold determination for when a landfill must in stall and operate a GCCS based on surface emission monitoring using EPA

Method 21. This alternative emission threshold dete rmination is

referred to as “Tier 4.” The Tier 4 SEM demonstrati on would

allow landfills that have modeled NMOC emission rat es (using Tiers 1, 2, or 3) at or above the threshold to demo nstrate that site-specific methane emissions are actually below the

threshold. A landfill that can demonstrate that sur face emissions are below 500 ppm for 4 consecutive quart ers does not trigger the requirement to install a GCCS. Tier 4 w ould be based***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 64 of 324 on the results of quarterly site-specific methane e missions monitoring of the entire surface of the landfill al ong a 30- meter (98-ft) path, in addition to monitoring areas where visual

observations indicate elevated concentrations of la ndfill gas, such as distressed vegetation and cracks or seeps i n the cover and all cover penetrations. If the landfill opts to use Tier 4

for its emission threshold determination and there is any measured concentration of methane of 500 parts per million or greater from the surface of the landfill, the owner or operator must install a GCCS, and the landfill cannot go bac k to using Tiers 1, 2, or 3. Because Tier 4 is based on site-s pecific

actual surface data whereas Tiers 1-3 are based on modeled emission rates, the EPA is requiring a GCCS to be i nstalled and operated within 30 months of a Tier 4 exceedance of 500 ppm or higher. D. Proposed Changes to Address Closed or Non-Produc ing Areas 1. Subcategory for Closed Landfills. The EPA recognizes that many landfills subject to p roposed subpart Cf are closed. Therefore, the EPA is propos ing a separate subcategory for landfills that closed on o r before [insert date of publication in the Federal Register ] . These landfills would be subject to a 50 Mg/yr NMOC emiss ion rate threshold, consistent with the NMOC thresholds in s ubparts Cc and WWW of 40 CFR part 60. These landfills would al so be exempt***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 65 of 324 from initial reporting requirements, provided that the landfill already met these requirements under subparts Cc or WWW of 40 CFR part 60. The EPA also solicits comments on an alternative approach which would expand the closed landfill sub category to

include those landfills that close within 13 months after publication of the final emission guidelines. 2. Alternative Criteria for Removing GCCS. The EPA also recognizes that many open landfills su bject to proposed subpart Cf contain inactive areas that do not produce as much landfill gas. Therefore, the EPA is also pr oposing an alternative set of criteria for determining when it is appropriate to cap or remove a portion of the GCCS. The proposed alternative criteria for capping or removing the GC CS are: (1)

the landfill is closed or an area of an active land fill is closed, (2) the GCCS has operated for at least 15 y ears or the landfill owner/operator can demonstrate that the GC CS will be unable to operate for 15 years due to declining gas flows, and (3) the landfill owner or operator demonstrates tha t there are no surface emissions of 500 ppm methane or greater for 4 consecutive quarters. With these provisions, the la ndfill can employ various technologies or practices to minimiz e surface emissions and have the flexibility to decommission or permanently cap and remove the GCCS based on site-s pecific surface emission readings. Note that the EPA is req uesting Commented [A6]: OMB General Comment 6: Reviewer recommends providing for more time for existing facilities to close to be included in the closed facility subcategory. The reasoning behind this subcategory would apply equally well to facilities close to the end of their useful life. Because of the time it will take to implement changes to the emissions guidelines, reviewer recommends that EPA propose included facil ities that within 13 months after the publication of the final emission guidelines (a period of time likely before the first SIPs would be approved) for facilities to close and be included in the closed subcategory. Response: Additional text has been added to specifically request comment on the closed landfill subcategory to include those landfills that close within 13 months after publication of the final emission guidelines.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 66 of 324 comment on defining closed areas of open landfills as discussed in section X.A of this preamble. E. Other Proposed Changes

1. Treated Landfill Gas. The EPA is proposing a definition of treated landfi ll gas and treatment systems. Specifically, the EPA propos es to define Treated landfill gas as landfill gas processed in a treatment system meeting the criteria in proposed 40 CFR part 60, subpart Cf and to define Treatment system as a system that filters, dewaters, and compresses landfill gas. The proposed d efinition

allows the level of treatment to be tailored to the type and design of the specific combustion equipment, chemic al process, or other purpose for which the landfill gas is used . These

definitions would be available for all MSW landfill owners/operators. Owners/operators would identify m onitoring parameters, develop a site-specific treatment syste m monitoring plan, and keep records that demonstrate that such p arameters effectively monitor filtration, de-watering, and co mpression system performance necessary for the end use of the treated landfill gas. Uses of Treated LFG. In addition, the EPA is propos ing that the use of treated landfill gas not be limited to u se as a fuel for a stationary combustion device but also for oth er beneficial uses such as vehicle fuel, production of high-Btu g as for***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 67 of 324 pipeline injection, and use as a raw material in a chemical manufacturing process. 2. Startup, Shutdown, and Malfunction Provisions. The general provisions in 40 CFR part 60 provide th at emissions in excess of the level of the applicable emissions limit during periods of startup, shutdown and malfu nction (SSM) shall not be considered a violation of the applicab le emission limit unless otherwise specified in the applicable standard (see 40 CFR 60.8(c))(emphasis added). As reflected in th e italicized language, an individual subpart can supersede this provision. In this action, the EPA is proposing standards in 40 C FR part 60, subpart Cf that apply at all times, including perio ds of startup or shutdown, and periods of malfunction. In additio n, the EPA is proposing to add a recordkeeping and reporting requ irement for landfill owners or operators to estimate emissions during periods when the gas collection system or control d evice is not operating, to determine the severity of any emissio ns exceedance during such periods. 3. Other Proposed Changes We are proposing to revise the definition of “Modif ication” and “Household waste” “Solid waste,” and “Sludge” a nd to add a definition of “Segregated yard waste” to make clear the applicability of proposed 40 CFR part 60, subpart C f.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 68 of 324 Method 25A. Method 25A is being included in propose d 40 CFR part 60, subpart Cf. After reviewing the comments r eceived on the NSPS for new landfills proposed on July 17, 201 4, the EPA recognizes that the use of Method 25A is necessary for measuring outlet concentrations less than 50 ppm NMOC. Per Em ission Measurement Center Guidance Document 033 (EMC GD-03 3-available at http://www.epa.gov//ttn/emc/guidlnd/gd-033.pfd), Method 25A should be used only in cases where the outlet conce ntration is less than 50 ppm NMOC as carbon (8 ppm NMOC as hexa ne). Method 18. Method 18 is not included in proposed 40 CFR part 60, subpart Cf. While Method 18 may be used in conjunction with Method 25A for methane or specific compounds o f interest, there are limitations on the number of analytes tha t can be reasonably quantified in measuring the sum of all N MOCs. With the possibility of 40 target analytes listed in the current landfill section of AP-42 (160 analytes in the draf t landfill AP-42), Method 18 is not an appropriate or cost eff ective method to test all NMOCs found in landfill samples. The ex tensive quality assurance required by the method makes the method technically and economically prohibitive for all th e potential target analytes. Surface monitoring intervals. The EPA is clarifying that surface emissions monitoring can be conducted at an interval less than specified in the rule text. Thus, the EPA is adding***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 69 of 324 “no more than” in front of the specified interval i n proposed 40 CFR part 60, subpart Cf (i.e., at no more than 30-m eter intervals). V. Rationale for the Proposed Changes Based on GCCS Technology

Review A. Control Technology Review 1. Gas Collection and Control Systems The EPA has determined that a well-designed and wel l operated GCCS that collects the LFG from the landfi ll and routes the collected gas to a combustion device that reduc es NMOC by 98 percent by weight or an outlet concentration of 20 ppmvd of NMOC, as hexane, or to a treatment system that proc esses the gas for subsequent beneficial use in a process that ens ures that

such reductions are achieved continues to be BSER f or controlling LFG emissions for both new and existing MSW landfills. As discussed in section IX.A of this pre amble, landfill gas energy recovery has environmental bene fits in controlling emissions and offsetting conventional e nergy sources. The BSER determination is based on the EPA ’s review of

the NSPS for new landfills as described in the land fills NSPS proposal at 79 FR 41800-41805, as well as public co mments and information received on the proposed NSPS (79 FR 41 796) and public input received on both the proposed NSPS and the ANPRM (79 FR 41772) for existing landfills.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 70 of 324 The majority of comments on this topic, received in response to the proposed NSPS (79 FR 41796), includ ing those from industry owners and operators, landfill engine ering consultants, and trade organizations, as well as in put received in response to the ANPRM (79 FR 41772), agreed that a GCCS and 98 percent NMOC destruction represent BSER for MSW landfills. 2. Open Flares and Destruction Efficiencies 98 Percent Reduction. The EPA is proposing 98 perce nt reduction of NMOC, expressed as a performance level (i.e., a rate-based standard or percent control), as the app ropriate BSER-based standard. The EPA previously determined that this level was reasonable considering costs, nonair qual ity health and environmental impacts, and energy requirements 39 . That determination still stands today and the EPA propos es 98 percent NMOC reduction for proposed 40 CFR part 60, subpart Cf. The following combustion controls can achieve at least 98 percent destruction of NMOCs and we propose that they conti nue to represent BSER: enclosed flares and incinerators, a nd devices that burn landfill gas to recover energy, such as b oilers, turbines, and internal combustion engines. The EPA solicits

comment on whether these devices can in fact achiev e at least 98

39 Air Emissions from Municipal Solid Waste Landfills —Background Information for Final Standards and Guidelines, EPA–453/R–94–02 1. EPA Office of Air and Radiation/Office of Air Quality Planning and Standa rds, Emission Standards Division, December 1995, page 2–79.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 71 of 324 percent destruction of NMOCs and whether uses of th e landfill gas other than for combustion achieve equivalent re ductions. Note that although the landfills rules measure NMOC , similar reductions are expected for methane. 40 The EPA continues to believe that 98 percent reduct ion is appropriate because this continues to be the level achievable by demonstrated technologies. Current data are consist ent with 98 percent destruction. Nonetheless, in the Federal Re gister notice for the proposed NSPS (79 FR 41803), we requested c omment and additional data on the NMOC destruction efficiency of incinerators and devices that burn landfill gas to recover energy, such as boilers, turbines, and internal com bustion engines. The EPA did not receive new data on the NM OC destruction of energy recovery devices. Open/Non-enclosed Flares. Both enclosed and non-enc losed (open) flares have been determined to be BSER combu stion devices

40 Methane is more readily combustible than other org anic compounds, thus methane generally has higher destruction (or contro l) efficiencies than other organic compounds such as NMOC and VOC. Therefore, although compliance with the landfills regulations is expressed as a percent reduction (or reduction to a level of 20 ppmv) of NMOC, landfills that redu ce NMOC by 98 percent reduce methane by a similar percentage. Two EPA pro grams use a 99 percent destruction efficiency for methane: the U.S. Greenh ouse Gas Emissions and Sinks: 1990-2013 and the Greenhouse Gas Reporting P rogram. In addition, the EPA’s AP-42 Compilation of Air Pollutant Emission F actors, Chapter 2.4 (1998), contains typical NMOC control efficiencies of 94-99+ for various devices used at landfills, including flares, intern al combustion engines, boiler/steam turbines, and gas turbines. Draft upda tes (2008) to AP-42 contain typical NMOC control efficiencies for flare s of 97.7 percent. Because methane is more readily combustible than NMOC, meth ane destruction efficiencies would be at least at this level. Commented [A7]: OMB General Comment 3: Reviewer recommends clarifying in the rules whether the cited 98% effectiveness of GCCS at destroying NMOCs (referenced throughout the rules) is also 98% effective at destroying methane. Response: Additional text and footnote added***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 72 of 324 and these technologies continue to be used today. C ommenters on the proposed landfills NSPS noted the prevalence of non-enclosed flares as both a primary and secondary control devi ce. Commenters contend that non-enclosed flares used at landfills meeting the criteria in 40 CFR 60.18(b) have been d emonstrated

to have destruction efficiencies similar to enclose d flares and incinerators, and devices that burn landfill gas to recover energy, such as boilers, turbines, and internal com bustion engines.

Commenters on the NSPS did not submit new data on f lare performance. However, one commenter included a stat ement of a guaranteed 98 percent destruction efficiency from a commonly used flare technology provider at landfills. 41 Commenters on the proposed NSPS (79 FR 41796) and information submitt ed in response to the ANPRM (79 FR 41772) indicate that h undreds of open/non-enclosed flares are currently in use and t hat these flares are fully capable of achieving a performance standard of 98 percent reduction of NMOC. The use of open/non-e nclosed flares is supported because of their inherent flexi bility in addressing multiple operational components includin g flow rate, Btu content, other gas constituents, proximity to n eighbors, and

41 Comment submitted by Republic Waste Services (EPA- HQ-OAR-2003-0215-0100). Attachment 15 includes statement from John Zink Com pany on standard emissions for elevated flares.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 73 of 324 cost. The information provided also indicates that open/nonenclosed flares are simpler and therefore easier an d less expensive to operate when compared with enclosed co mbustion devices; in addition, their simplicity makes them l ess susceptible to malfunctions or shutdowns. A better turndown ratio for open/non-enclosed flares was cited as an important consideration in addressing variable operating flowrates over the life of the landfill. The ability to use flares as a back up to LFG energy recovery projects is also an importan t consideration. One commenter on the proposed landfills NSPS did, h owever, state that EPA should not consider open flares to b e part of the BSER for landfills, given issues with their perform ance in reducing emissions. The commenter provided several references that identified the difficulty in measuring the per formance of flares and poor or questionable flare performance w hen measurements were made, especially in windy conditi ons. Based on the operational flexibilities open flares offer landfill operators, and the flare design and operat ional requirements in the general provisions, the EPA is retaining the option for landfills to comply with proposed 40 CFRpart 60, subpart Cf using an open flare operated in accordan ce with 40 CFR 60.18(b) of the general provisions. The EPA mai ntains that the design and operational requirements set forth i n 40 CFR***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 74 of 324 60.18(b) ensure that open flares are operated to ad equately destroy NMOC to a level consistent with NMOC destru ction requirements for other control devices. The general provisions require a minimum heating value to ensure combustio n efficiency. Specifically, 40 CFR 60.18(c)(3)(ii) requires the n et heating value of the gas being combusted to be 7.45 megajou les per standard cubic meter (MJ/scm)(200 Btu/standard cubi c foot) or greater if the flare is nonassisted or 11.2 MJ/scm (300 Btu/scf) or greater if the flare is steam-assisted or air-as sisted. Landfill gas typically contains 50 percent methane, but methane content generally ranges from 45 to 60 percent, dep ending on several factors including waste characteristics andlandfill design and operation activities. This range of meth ane contents is equivalent to landfill gas heating values of app roximately 450 to 600 Btu/scf, which are above the minimum net heating values outlined in 40 CFR 60.18(c)(3)(ii). Regardle ss of the specific methane content of landfill gas, the landf ill owner or operator must calculate the net heating value of th e landfill gas for comparison to the appropriate minimum net h eating value defined in 40 CFR 60.18. Proposed subpart Cf (40 CF R 60.35f(d)) complements the general provision requirements by r equiring three 30-minute samples obtained by Method 3C. Thes e rule provisions ensure that the landfill gas burned in t he flare has***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 75 of 324 adequate heating value to ensure complete combustio n, which in turn, ensures adequate NMOC destruction. Note that flares at landfills are typically non-ass isted and generally have low variability in the flow of l andfill gas. A non-assisted, relatively constant flow of gas mea ns there is nothing to dilute or interrupt the mixture of gas i n the combustion zone. Thus, landfill gas and its compone nts are destroyed more efficiently. In addition, with respe ct to concerns about operating flares in windy conditions , the EPA has found extremely limited data exists to indicate tha t wind conditions adversely affect destruction efficiencie s of flares. Studies cited regarding wind conditions are based o n experiments conducted in laboratory environments using very sma ll diameter flares (4.5 to 6 inches) that are more susceptible to wind than larger diameter flares used at MSW landfills. Although flaring remains one compliance option for collecting and controlling emissions of landfill ga s, the EPA believes that the use of landfill gas to produce en ergy represents a higher value use and requests comments on whether there are opportunities to incentivize the use of l andfill gas for energy production rather than flaring. Thus, th e EPA solicits comments on incentive approaches to encour age landfill owner/operators to productively use landfill gas fo r energy.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 76 of 324 3. Emission Reduction Techniques and GCCS Best Mana gement

Practices In the ANPRM for existing landfills (79 FR 41784), the EPA presented several alternative technologies, includi ng oxidative technologies, that could potentially serve as a component of BSER. The principle of oxidative technologies is th e use of methanotrophic bacteria, commonly found in most soi ls and compost, to oxidize methane into water, carbon diox ide, and biomass. The EPA also presented information on vari ous BMPs that could improve the operation and performance of GCCS and thus

achieve additional emission reductions. Such BMPs i ncluded installing final cover early to increase gas collec tion efficiency, connecting the leachate collection and removal system (LCRS) to a GCCS, providing redundant seals on wellheads, installing horizontal collectors to facilitate earl ier gas collection (i.e., shorter lag times), and preventin g flooded wells via the use of pumps and surface collectors. The EPA received comments both supporting and objecting to considering BMPs and oxidative control technologies as BSER. Commenters generally pointed out the site-specific nature of the various GCCS BMPs. Several commenters disagr eed that the EPA should prescribe enhanced wellhead seals in the rule and indicated that landfill operators are already emplo ying sitespecific approaches to ensure that wells are proper ly sealed in***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 77 of 324

order to avoid exceedances of wellhead standards an d maintain good gas quality. Regarding connecting to a LCRS, t wo commenters raised several technical site-specific issues assoc iated with connecting an LCRS to a GCCS. Several commenters in dicated that LCRS connections are typically shallow and can intr oduce ambient air into the GCCS, which could increase the risk of subsurface fire. According to these commenters, to reduce thes e risks, each individual connection point of an LCRS would need t o be

evaluated to determine if it was suitable for conne ction to a GCCS. For cover, several commenters stated that lan dfill cover materials must meet multiple objectives, including controlling odors, vectors, fires, and litter, shedding moistur e to reduce infiltration, and supporting vegetation and compact ion. One of

the commenters added that Resource Conservation andRecovery Act (RCRA) and state and local regulations govern many of these cover criteria and expressed concerns that cover re quirements in the Emission Guidelines could be contradictory to o ther requirements. These commenters indicated that as la ndfill owners and operators select cover materials and designs in tended to promote methane oxidation, such as biocovers or cov er soils, these performance objectives should be taken into c onsideration. Other commenters advocated for requiring BMPs inclu ding enhanced or duplicate seals on wellheads, connectio ns to LCRS to***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 78 of 324 collect LFG, early final covers, horizontal collect ors, and BMPs for dewatering gas collection wells. With respect to oxidative covers, several commenter s mentioned or provided information on articles and o ther literature that discuss selecting appropriate bioco ver materials. 42 Some of these commenters noted that the rate of oxidation depends on both material properties and s ite-specific operations, including moisture, temperature, materi al particle size, depth, and compaction. One state agency agree d that

methane oxidation is well demonstrated for cover ma terials such as compost or yard waste, but expressed concern tha t methane oxidation performance in extreme climate conditions is not well known, in particular as related to daily and interm ediate cover thicknesses. One commenter expressed concerns that the use of an oxidizing cover can reduce gas collection efficienc y and should not be required by the Emission Guidelines. Several commenters expressed concern with whether t he longterm performance of oxidative control technologies in real-world conditions has been established for controlling lan dfill methane and NMOC emissions. Several commenters appreciated the EPA’s willingness to recognize the role of oxidation in m itigating methane and NMOC emissions and agreed that the use of biocovers

42 Refer to pages 55-56 of the original comment lette r at DCN EPA-HQ-OAR-2003- 0215-0100 for references.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 79 of 324 or biofilters for landfill methane oxidation is pro mising but did not recommend requiring oxidative controls in t he Emission Guidelines. A couple of these commenters indicated that these technologies are not BSER, one of which specificall y noted that biocover technology has not been sufficiently demon strated to support a regulatory requirement under CAA section 111, as that requires the EPA to determine pe r formance standards based on adequately demonstrated technology. The EPA recognizes the site-specific nature of GCCS design and operation and that the effectiveness of any par ticular BMP, therefore, depends on the site-specific circumstanc es of a particular MSW landfill. Therefore, while EPA stron gly encourages the use of appropriate BMP to ensure the best possible design and operation of each GCCS, EPA doe s not consider any particular BMPs to constitute BSER and , thus, is not proposing to prescribe the use of GCCS BMPs in proposed 40 CFR part 60, subpart Cf. The EPA continues to belie ve that BSER remains a well-designed and well-operated GCCS and that while all such systems have certain characteristics in co mmon, what constitutes a well-designed and well-operated GCCS will vary somewhat from landfill to landfill. While we agree with commenters that these alternative technologies and BMPs can

achieve additional reductions in some circumstances , the performance, cost, and technical feasibility of the se BMPs can***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 80 of 324 vary greatly from site to site as well as from cell to cell even within the same site. Further, designing specific c omponents of a GCCS (e.g., biofiltration cells, prescribed wellh ead seals, horizontal collectors, LCRS connection to GCCS, andsurface collectors) depends on climate-specific and site-sp ecific conditions that must be assessed on a case-by-case basis and requires engineering judgment, which is best exerci sed by the professional engineer that reviews the GCCS design plan for approval and the staff at each delegated authority responsible for approving the GCCS design plan. The EPA recognizes that the effectiveness of cover practices, both early installation of final cover a nd the use of oxidative covers in reducing emissions is also site -specific. Therefore, the EPA does not consider these to const itute BSER and is not proposing to prescribe specific cover pr actices in proposed 40 CFR part 60, subpart Cf. The timing of final cover installation depends on the filling sequence and ce ll design of the particular landfill. For biocovers, the applica bility is dependent on whether the area is closed or open. Th e materials

allowed to be used for oxidative covers could also vary from site to site depending on state or local yard waste or compost bans, materials most favorable to the local climate , or materials that are best suited to meet multiple sit e-specific performance objectives in addition to reducing land fill gas***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 81 of 324 emissions. The EPA also agrees with commenters who noted that long-term performance of oxidative covers has not y et been adequately demonstrated in a full-scale industrial setting at a

landfill. Based on the information and public input it receiv ed on emission reduction techniques and various BMPs that could improve collection and control of LFG emissions, th e EPA proposes to conclude that BSER does not include spe cific GCCS BMPs, cover practices, or oxidative controls and, t herefore, is not proposing to require landfills to adopt those p ractices in

the Emission Guidelines. The EPA does not consider oxidative technologies (biocovers and biofilters) or BMPs to be part of

BSER. Although the EPA is not prescribing BMPs for GCCS o r advanced cover practices in proposed 40 CFR part 60 , subpart Cf, the EPA expects that two proposed rule flexibilitie s will encourage and promote more widespread adoption of B MPs and alternative cover technologies. First, the proposedTier 4 surface monitoring demonstration allows a landfill owner/operator to use site-specific surface methane emissions measurements prior to determining when the installa tion of a regulatory compliant GCCS is required. (The Tier 4 surface

emissions threshold is discussed in section VII.A o f this preamble. Tier 4 may also be used to determine when the GCCS can***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 82 of 324 be removed, as discussed in section VIII of this pr eamble.) Thus, the EPA expects that at least some landfill o wners or operators will utilize oxidative cover practices or BMPs such as early gas collection or LCRS connection to minimize surface

emissions. Second, the EPA is proposing to remove the wellhead temperature and oxygen/nitrogen performance require ments and the corresponding requirement to take corrective action upon exceeding one of these parameters, thereby providin g flexibility with regard to wellhead operating parameters. (The wellhead operating parameters are discussed in section VI.B of this preamble.) With the proposed wellhead operating par ameter flexibility, landfill owners and operators may empl oy cover practices or GCCS BMPs that are suitable for their sites and GCCS designs, thereby allowing them to collect more LFG and reduce emissions without the risk of exceeding a we llhead operating parameter. In addition to these two flexibilities, the EPA is requesting comment on other compliance flexibilitie s to better promote the use of GCCS BMPs that could be used in the final Emission Guidelines. To complement the compliance f lexibilities proposed in these Emission Guidelines, the EPA inte nds to explore the creation of technical assistance docume nts and other tools or resources for educating the owners/ operat ors of***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 83 of 324 affected landfills and delegated authorities about how GCCS BMPs and oxidative controls can be implemented effective ly to achieve

additional methane and NMOC emission reductions fro m landfills. 4. Organics Diversion and Source Separation Landfill gas is a by-product of the decomposition o f organic material in MSW under anaerobic conditions in landfills. The amount of LFG created primarily depends on the quantity of waste and its composition and moisture content, as well as the design and management practices at the site. Food w aste, yard debris, and other organic materials continue to be the largest component of MSW discarded, with food waste compris ing the largest portion. Decreasing the amount of organics disposed in landfills would reduce the amount of LFG generated. As previously discussed in this section V.A, we are proposing to define BSER as a well-designed, instal led and operated GCCS. We are proposing to conclude that or ganics diversion and source separation are not part of a w ell-designed, installed and operated GCCS and, therefore, not par t of BSER. The EPA does, however, consider organics diversion and source separation advantageous because such practices redu ce the amount of LFG generated and thus may serve as a useful compliance tool as it may allow landfill owners and operators to po stpone the

need to install a GCCS.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 84 of 324 In the ANPRM for existing landfills (79 FR 41787, J uly 17, 2014), the EPA solicited input on methods to encour age organics diversion in any proposed revised Emission Guidelin es. The EPA received a variety of ideas on how best to encourag e diversion. Many commenters generally recognized that organics

diversion could achieve emission reductions from la ndfills. Although the ANPRM (79 FR 41772) specifically state d EPA was not soliciting comments on mandating organics diversion , many commenters cautioned against an organics diversion mandate in the Emission Guidelines, given the complexity and l ocal nature of waste management. Specific examples of how a Tie r 4 emission threshold determination and flexible wellhead opera ting parameters could encourage more landfills to adopt organics diversion programs were provided, as discussed in s ections VI, VII, and VIII of this preamble. Several commenters suggested that the EPA encourage partial organics diversion p rograms instead of focusing on rule exemptions for landfill s with 100 percent diversion rates, which commenters said is i mpractical at this point given current infrastructure and technol ogy limitations. One commenter touted the economic and job creation benefits of increased organic diversion rates. A st ate agency suggested that a separate subcategory with a higher design capacity threshold could be developed for landfills diverting organics. Another commenter suggested that the EPA should***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 85 of 324 provide states the flexibility to incorporate both source control requirements and landfill diversion program s into their state plans. States and municipalities in the U.S. are increasin gly moving toward the diversion of organic wastes from landfills to composting and anaerobic digesters. At least 21 sta tes have mandated organics diversion and/or banned disposal of at least some organics (primarily yard waste) from landfills . Five of these states (California, Connecticut, Massachusett s, Rhode Island, and Vermont) have enacted legislation gover ning organics disposal specific to food waste. 43 In addition, state initiatives to recycle organic wastes have contributed to the g rowth of local residential organics collection, with 198 communities in 19 states reporting curbside collection of food scr aps. 44 Between 2009 and 2014, the number of municipalities with so urce separated food waste collection more than doubled ( from 90 to 198) and the number of affected households grew by nearly 50 percent. 45 Separate collection and treatment of organics in t he

commercial and institutional sectors has also risen . The nature of organics management initiatives and programs at the state and local levels varies across the country by several f actors,

43 U.S. EPA, Regulatory Impact Analysis for Proposed Emission Guidelines and Compliance Times for Municipal Solid Waste Landfill s, Section 2.7, 2015. 44 Ibid. 45 Ibid.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 86 of 324 including type of organics targeted (e.g., food was te, yard waste), source of organics generation (e.g., commer cial, residential, institutional), implementation phase ( e.g., pilot projects, mandatory with fines for violations), andpricing formats (e.g., “pay-as-you-throw,” property tax, fi xed fee). The EPA recognizes the emission reduction benefit o f organics diversion from landfills. A recent study i ndicated that modest organics diversion programs could achieve a 9 percent reduction in LFG generation rates, while more aggre ssive diversion programs could yield up to 18.5 percent r eduction. 46 Nevertheless, while the EPA has proposed several pa thways to encourage voluntary organics diversion in this prop osal, the EPA is not proposing a federal mandate of organics dive rsion under this proposal. There are significant barriers to is suing a

federal mandate for diversion under the Emission Gu idelines, including: lack of regulations and incentives at th e state and local level; limited processing and transfer capaci ty for organic wastes; low cost to dispose of waste in lan dfills relative to other waste treatment technologies; mul tifaceted and regional nature of the solid waste management indus try; and behavioral changes needed among waste generators (i ndividuals,

46 Stege, Alex. The Effects of Organic Waste Diversio n on LFG Generation and Recovery from U.S. Landfills. SWANA’s 37 th Annual Landfill Gas Symposium. 2014.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 87 of 324 businesses, and industries) to divert their organic wastes from

landfills. 47 In the 1996 Landfills NSPS Background Information

Document 48 , the EPA “decided not to include materials separat ion requirements within the final rules because the EPA continues to believe RCRA and local regulations are the most app ropriate vehicle to address wide-ranging issues associated w ith solid waste management for landfills.” The EPA continues to believe that this is the case. The EPA has, however, propos ed three compliance flexibilities as discussed in sections V I.B (wellhead monitoring), VII.A (Tier 4 emission threshold deter mination), and VIII.B (Criteria for Capping or Removing a GCCS ) of this preamble that may aid landfills in increasing organ ics diversion. The proposed adjustments to wellhead ope rating standards provide some GCCS operational flexibility to accommodate declining LFG quantity or quality resul ting from modified waste composition at landfills employing a n organic diversion program. The formats of the Tier 4 option and

alternative set of surface emission-based GCCS remo val criteria

serve as built-in incentives for the landfill owner /operator to

47 Ibid. 48 Air Emissions from Municipal Solid Waste Landfills -Background Information for Proposed Standards and Guidelines, U.S. EPA (EP A-450/3-90-011a) (NTIS PB 91-197061).***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 88 of 324 implement a variety of surface emission reduction t echniques, including organics diversion. In addition to the three compliance flexibilities d iscussed in sections VI.B (wellhead monitoring), VII.A (Tier 4 emission threshold determination), and VIII.B (criteria for capping or removing a GCCS), the EPA is seeking comment on oth er compliance flexibilities it should consider when issuing the f inal Emission Guidelines to encourage more organics diversion. Th e EPA is also requesting comment on other ways we could structure the guidelines to credit organics diversion. In response to public input, the EPA is also seekin g comment on what, if any, role organics diversion po licies or measures could play in an approvable state plan. Th e EPA must ensure that each state plan establishes requirement s for LFG emission controls that are at least as stringent as the Emission Guidelines. We are, therefore, interested in how st ates might demonstrate that a state plan that contains organic s diversion policies and measures is at least as stringent as t he Emission Guidelines. The EPA is interested in supporting sta te organics diversion initiatives and one way of doing this may be to provide flexibility to include such initiatives as a component of an approvable state plan. As previously stated, however, to be approvable, a state plan must be at least as str ingent in its effect on LFG as the Emission Guidelines, i.e., it must ensure***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 89 of 324 emission reductions equivalent to those achieved wi th a welldesigned, installed, and well-operated GCCS with a NMOC destruction efficiency of 98 percent and we are not surerequest

comments on how a state that relies on organics diversion coul d do this. The EPA, through its various voluntary pro grams intends to explore the creation of outreach materials, tech nical assistance documents, trainings, and other tools or resources for educating owners and operators of affected land fills and implementing authorities about the benefits of orga nics diversion and how organics diversion programs can b e implemented effectively to achieve additional reductions in met hane and NMOC emissions from landfills. The EPA is also exploring opportunities through its voluntary programs to rec ognize leadership in diverting organics from landfills.

B. What data and control costs did the EPA consider in evaluating potential changes to the timing of insta lling, expanding, and removing the GCCS? To examine the potential impact of changes to the t iming of initiating and removing landfill gas collection andcontrol, the EPA updated a dataset of information for landfills, as described below, and applied a model to assess when controls were needed under the baseline control scenario (2.5 million Mg design capacity threshold and 50 Mg/yr NMOC threshold) as well as various regulatory options.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 90 of 324

As discussed at 79 FR 41805 , in determining whether to revise the proposed standards of performance for ne w MSW landfills, the EPA developed a dataset of informati on for landfills, which included landfill-specific data su ch as landfill open and closure year, landfill design cap acity, landfill design area, and landfill depth. For the r egulatory analysis, we approximated the number of landfills t hat would become subject to the regulation based on size usin g the reported design capacities, which were provided in units of megagrams. For purposes of rule applicability, size is based on both mass (Mg) and volume (m 3 ). The EPA made several significant updates to this or iginal dataset to evaluate the impacts of this proposal. N otably, the EPA updated the technical attributes of over 1,200 landfills based on new detailed data reported to 40 CFR part 98, subpart HH of the Greenhouse Gas Reporting Program (GHGRP). In addition, the EPA consulted with its regional offices, as wel l as state and local authorities, to identify landfills expect ed to undergo a modification within the next 5 years. According t o the applicability of the proposed subpart XXX, if a lan dfill

commenced construction on its modification after Ju ly 2014, it would no longer be subject to the state or federal plans implementing these proposed revisions to the Emissi on Guidelines; therefore, these landfills were exclude d from the***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 91 of 324 impacts analysis conducted for this proposal, and t heir impacts will be considered as part of the final revisions t o the standards of performance for new (and modified) lan dfills issued under 40 CFR part 60, subpart XXX. After incorporat ing all of the updates to the inventory and taking out the lan dfills expected to modify, the revised dataset now has 1,8 39 existing landfills that accepted waste after 1987 49 and opened prior to

2014 50 that are analyzed in this regulatory options analy sis. A detailed discussion of updates made to the landfill dataset is in the docketed memorandum, “Summary of Updated Lan dfill Dataset Used in the Cost and Emission Reduction Analysis of Landfills Regulations. 2015.” The EPA programmed a Microsoft® Access database (hereinafter referred to as the “model”) to calcula te the costs and emission reductions associated with the regulat ory options

for each of the landfills in the revised dataset. T he default parameters for methane generation potential (L 0 ), the methane

49 November 8, 1987 is the date on which permit progr ams were established under the Hazardous and Solid Waste Amendments of R CRA. This date was also selected as the regulatory cutoff in the emission g uidelines for landfills no longer receiving wastes because the EPA judged stat es would be able to identify active facilities as of this date. The dat a available to EPA includes an open year without the month and so the analysis uses a cutoff year of 1988 for landfill closure year.

50 July 17, 2014 is the proposed date of the revised NSPS for MSW landfills in 40 CFR part 60, subpart XXX. A landfill opening or commencing construction on its modification after this date would become subje ct to this new subpart and would not be subject to the revised emission guidel ines. The EPA cannot predict the exact month a model landfill will open so the analysis uses a cutoff year of 2014.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 92 of 324 generation rate (k), and the NMOC concentration use d to estimate when the landfills exceeded regulatory emission thr esholds and

estimate emission reductions are the same as those discussed at 79 FR 41805. Similarly, the default parameters for methane generation potential (L 0 ), the methane generation rate (k), and

the NMOC concentration used to estimate when landfi lls could cap

or remove controls are the same as those discussed at 79 FR

41805. When modeled landfill gas emissions for a particula r landfill exceeded the emission rate threshold, the EPA assumed that collection equipment was installed and startedoperating at the landfill 30 months after first exceeding the th reshold (as discussed in the docketed memorandum “Methodology f or Estimating Cost and Emission Impacts of MSW Landfills Regulati ons. 2014”).

The EPA also assumed that as the landfill was fille d over time, the landfill would expand the GCCS into new areas o f waste placement according to an expansion lag time of 5 y ears for active areas and 2 years for areas that are closed or at final grade. Based on input received during public outrea ch to small entity representatives (SERs) as well as comments r eceived on the proposed NSPS (79 FR 41796), most modern large landfills do not reach final grade within 2 years and a majority of landfills are complying with the 5 year provision.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 93 of 324 Although we are proposing a new Tier 4 option as a sitespecific alternative for determining if a landfill has exceeded the regulatory emission threshold (and must install controls) or if a landfill has fallen below the regulatory emiss ion threshold (and can remove or cap controls), the number and ty pes of landfills that could opt to use a Tier 4 option are unknown and could not be incorporated into the impacts calculat ed in the model. As a result, the number of landfills expecte d to control under each regulatory option, as well as the estima ted emission reductions and costs associated with each regulator y option are based on modeled estimates of landfill gas emission s. To estimate the costs of each regulatory option, th e EPA made minor changes to the cost methodology discusse d in the landfills NSPS proposal at 79 FR 41805. In this ana lysis, cost equations were obtained from a recent update to EPA ’s Landfill Gas Energy Cost Model (LFGcost-Web), version 3.0, w hich was updated by EPA’s Landfill Methane Outreach Program (LMOP) in August 2014. The EPA also updated estimates for sur face emission monitoring costs based on revised estimates made av ailable to the EPA since proposal of the NSPS in July 2014. The capital costs continue to be presented in year 2012 dollars and annualized using an interest rate of 7 percent over the lifetime of the equipment (typically 15 years), or in the case of drill mobilization costs, the length of tim e between***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 94 of 324 each wellfield expansion. These annualized capital costs were added to the annual operating and maintenance costs estimated by LFGcost-Web. The annualized cost includes capital r elated to the purchase, installation, operation and maintenance o f GCCS, and costs related to testing and monitoring. For certain landfills that were expected to generat e revenue by using the LFG for energy, the EPA also e stimated LFG energy recovery rates and associated costs to insta ll and operate the energy recovery equipment as well as th e revenue streams from the recovered energy. These revenues w ere subtracted from the annualized capital and operatin g and

maintenance costs at each landfill in order to obta in a net cost estimate for each option in each year. The emission reduction and cost and revenue equations and assumptions are detailed in the docketed memoranda, “Updated Methodology for Es timating Cost and Emission Impacts of MSW Landfills Regulations. 2015” and “Updated Methodology for Estimating Testing and Mon itoring Costs for the MSW Landfill Regulations. 2015.” C. What emissions and emission reduction programs a re associated with existing MSW landfills? The EPA estimates that the potential uncontrolled e missions from the approximately 1,800 landfills in its regul atory analysis dataset (as explained in section V.B of th is preamble) are approximately 69,700 Mg NMOC and 11.0 million M g methane***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 95 of 324 (275 million mtCO 2 e) in year 2014. In year 2025, the EPA estimates that the potential uncontrolled emissions from the approximately 1,800 landfills in the dataset are ap proximately 71,400 Mg NMOC and 11.2 million Mg methane (281 mil lion mtCO 2 e). The majority of landfills in the dataset are expect ed to remain open through 2025, thus uncontrolled emissions are higher in

2025. Looking beyond the modeled dataset, the Inventory o f U.S.

Greenhouse Gas Emissions and Sinks: 1990-2013 shows a growth in uncontrolled emissions from MSW landfills, from 205 .4 teragrams (Tg) CO 2 e in 1990 to 332.6 Tg CO 2 e in 2013. 51 If controls are considered, emissions from landfills have decreased from 173.8 Tg CO 2 e in 1990 to 97.5 Tg CO 2 e in 2013 from both regulatory and voluntary programs as discussed below. 52 1. Emission Reductions Due to Subparts Cc and WWW To estimate the emission reductions, the EPA applie d the current design capacity and NMOC emission rate thre sholds in the MSW landfills regulations, and the time allowed for installing, expanding and removing the GCCS to the modeled emis sion estimates discussed in section V.B of this preamble

.

51 U.S. EPA. Inventory of U.S. Greenhouse Gas Emissio ns and Sinks: 1990-2013. April 2015. Table 7-3. http://www.epa.gov/climatechange/ghgemissions/usinv entoryreport.html 52 Ibid, Annex 3.14, Table A-265.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 96 of 324 Table 2 of this preamble summarizes the reductions anticipated to be achieved in 2025 as a result of 4 0 CFR part 60, subpart WWW and the federal and state plans imp lementing the

Emission Guidelines. This table reflects the curren t baseline level of control at existing landfills: Landfills g reater than or equal to 2.5 million Mg and 2.5 million m 3 must install a GCCS when NMOC emissions reach or exceed 50 Mg/yr. The table

includes emission reductions for NMOC and methane. Table 2. Baseline Emission Reductions in 2025 at Ex isting Landfills

No. of landfi lls affect ed No. of

landfil ls control ling No. of

landfi lls report ing but not contro lling a Annual

Net Cost (milli on $2012) b Annual

NMOC Reduct ions (Mg/yr ) Annua

l Metha ne Reduc tions (mill ion Mg/yr ) Annual CO 2 e Reduct ions (milli on mt/yr) NMOC

cost effecti veness ($/Mg) Methan

e cost effect ivenes s ($/Mg) CO 2 e

cost effecti veness ($/mt) 989 574 211 299 57,300 9.0 226 5,090 32.3 1.3 a Excludes closed landfills from reporting count, b ecause the closed landfills are not expected to have to submit report s in 2025. They would have already submitted their one-time reports under 40 C FR part 60, subpart WWW or the state or federal plan implementing 40 CFR part 60, subpart Cc, and because they are closed, they would also be expecte d to be done with NMOC reporting by 2025 because they are on the tail end of their gas curve and gas rates are declining. b The annualized net cost ($299 million) is the dif ference between the average annualized revenue ($1,408 million) and the sum of annualized control cost ($1,700 million) and the average annualized te sting and monitoring costs ($7.3 million). The Emission Guidelines in the baseline are estimat ed to require control at 574 of the 989 affected landfill s in 2025 and achieve reductions of 57,300 Mg/yr NMOC and 9.0 mil lion Mg/yr methane (226 million mt/yr CO 2 e). In the baseline we estimate***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 97 of 324 that 31 percent (574/1,839) of existing landfills w ill operate

emission controls in 2025. 2. Other Programs Achieving Emission Reductions fro m Existing

MSW Landfills Landfill owners and operators collect LFG for a var iety of reasons: to control odor, to minimize fire and expl osion hazards, to recover LFG to be used for energy recov ery, to sell carbon credits, and to comply with local, state, or federal air quality standards. This section of this proposed ac tion discusses several non-EPA programs of which the EPA is aware. These reductions complement the reductions achieved by the

current NSPS and Emission Guidelines framework.

a. State and Local Ordinances

The EPA is aware that some state or local ordinance s require LFG combustion. The number of landfills con trolling

under these ordinances is unknown and is not factor ed into the incremental impacts analysis for this rule. The EPA is also aware that other states have rules regulating LFG c ombustion for odor control or safety reasons, which may be less c omprehensive than the requirements of a GCCS operated in accorda nce with the NSPS and emission guideline requirements.

b. Market-based Mechanisms Many of these systems may have been installed to re cover energy and generate revenue through the sale of ele ctricity or***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 98 of 324 LFG. Some landfills with voluntary systems may also receive

revenues as a result of the creation of carbon cred its. Data

from the Climate Action Reserve indicates that more than 115 LFG capture projects in 36 states have been issued cred its known as Climate Reserve Tonnes (CRTs). 53 To estimate the number of landfills that may be con trolling LFG emissions voluntarily, the EPA evaluated the mo st current data available and compared the list of landfills t hat are

modeled to have installed a GCCS in 2014 in the NSP S/Emission

Guidelines dataset to the list of landfills that ar e reported to have a GCCS installed in the LMOP or subpart HH GHG RP databases. While the NSPS/Emission Guidelines dataset estimate s that approximately 620 landfills have installed controls to meet the requirements of the NSPS or an approved state plan or federal plan implementing the Emission Guidelines, the LMOP and GHGRP databases show approximately 330 additional landfil ls as having installed controls, resulting in approximately 950 landfills

estimated to have a GCCS installed in 2014. 54 Approximately 55 percent of these 330 landfills exceed the design ca pacity of 2.5

53 Climate Action Reserve. Issued List of CRTs as of January 7, 2015. https://thereserve2.apx.com/myModule/rpt/myrpt.asp? r=112. 54 See sections V.B and V.C of this action for a deta iled discussion of the modeling database and estimated reductions under th e current federal regulatory framework.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 99 of 324 million Mg 55 , but as of 2014, are not modeled to exceed the NMO C

emission threshold that dictates when a GCCS must b e installed. In some cases these GCCS may have been installed ea rlier than required by the time frames currently specified in the NSPS and

Emission Guidelines. The LMOP database estimates th at nearly 120 of the 330 landfills with voluntary systems have an energy recovery component. Among landfills with design cap acities of 2.5 million Mg or greater, approximately 80 of the 180 landfills with a voluntary GCCS have an energy recovery compo nent. These 330 landfills are estimated to reduce approximately 12 million Mg CO 2 e in 2014. This is in addition to the 231 million M g CO 2 e reduction achieved by the current regulatory baseli ne. This represents an additional 5 percent reduction in yea r 2014 coming from systems installed for reasons other than compl iance with the NSPS or state and federal plans implementing th e Emission

Guidelines. D. What control options did the EPA consider? The EPA considered several factors when determining which control options would represent BSER. This section of the preamble describes those control options, which inc lude varying the design capacity threshold, varying the NMOC emi ssion rate

55 For the regulatory analysis, we approximated the n umber of landfills that would become subject to the regulation based on siz e using the reported design capacities, which were provided in units of megagrams. For purposes of rule applicability size is based on both mass (Mg) and volume (m 3 ).***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 100 of 324 threshold, and varying the time allowed to install and then expand the gas collection and control system. To ex amine these options, the EPA ran several permutations of variou s control options on the original dataset developed for the J uly 2014 NSPS proposal. Each regulatory option assessed variation s in the design capacity and/or emission rate thresholds, as well as changes to the initial lag time and expansion lag t ime. The “initial lag time” is the time period between when the landfill

exceeds the emission rate threshold and when contro ls are required to be installed and started up (30 months in 40 CFR part 60, subparts Cc and WWW). The “expansion lag t ime” is the amount of time allotted for the landfill to expand the GCCS into new areas of the landfill (5 years for active areas and 2 years for areas that are closed or at final grade in 40 C FR part 60, subpart WWW). Some options adjusted a single threshold in isolati on; for example, reducing the NMOC emission threshold to be tween 34 and 40 Mg/yr while keeping the design capacity threshol d constant at 2.5 million Mg. Other options adjusted multiple con trol parameters simultaneously, taking into account the relationship between the parameters. For example, recognizing th at NMOC emissions are a function of waste-in-place, some op tions that significantly reduced the NMOC emission threshold a lso reduced the design capacity thresholds to 2.0 million Mg to avoid***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 101 of 324

situations where the NMOC emission threshold would be exceeded long before the design capacity threshold. In addition to adjusting design capacity and emissi on control thresholds, other preliminary model runs va ried the initial and/or expansion lag times. These variation s estimated the impacts of requiring landfill owners or operato rs to install or expand gas collection systems more quickly after crossing

each modeled NMOC emission threshold. In 2013, the EPA presented different model runs dur ing Federalism consultations and small entity outreach that represented the range of variation in both the thre shold and lag time parameters. For the options presented, small e ntity representatives (SERs) and Federalism consultation participants provided feedback to the EPA, which included implem entation concerns with varying certain parameters as part of the Emission Guidelines review, as discussed in the following se ctions. The EPA also received comments on varying certain param eters in response to its July 2014 NSPS proposal and ANPRM f or Emission Guidelines at MSW landfills (79 FR 41772) and condu cted a subsequent round of Federalism consultations and sm all entity

outreach in 2015. The EPA considered these concerns and comments received on the July 2014 NSPS proposal and ANRPM w hen developing a revised set of regulatory options in t his proposal.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 102 of 324 1. What are the implementation considerations with changing the design capacity criteria? For this proposal, the EPA considered two different design capacity thresholds: no change from the current reg ulatory baseline of 2.5 million Mg and 2.5 million m 3 , and an option that reduced the design capacity to 2.0 million Mg and 2.0

million m 3 . This section of the preamble describes the result ing potential burden to regulated entities, including s mall entities. Potential burden includes obtaining a tit le V permit and calculating an annual NMOC emission rate. This discussion

also considers the size threshold associated with e xisting state regulations, as well as collection systems that are in place on a voluntary basis. The EPA did not consider an option to remove the de sign capacity criteria for this proposal so that all lan dfills would be affected sources no matter their size, because o f the burdens of permitting and reporting at small landfills as d iscussed

below and at 79 FR 41782. If the EPA were to remove the design capacity threshold, a significant number of additio nal landfills would be subject to the rule. Out of the approximat ely 1,800 existing landfills in the revised dataset, approxim ately 850 have a design capacity of less than 2.5 million Mg. Without a design capacity threshold, the NMOC emission rate w ould be the only criterion for installing controls. Thus, these 850***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 103 of 324 landfills would be required to begin calculating an d reporting their NMOC emission rate. They would also be requir ed to obtain a Title V permit. This would present a significant burden on both regulated landfills and delegated permitting a uthorities, which must be evaluated in light of potential emiss ions

reductions. The EPA did not analyze control options for landfil ls with landfill design capacities less than 2.0 million Mg in the model. Based on the revised dataset, 571 of the 623 closed landfills (91.6 percent) have a design capacity les s than 2.0 million Mg. Lowering the design capacity below 2.0 million Mg would cause a large number of closed landfills to b ecome subject to regulatory requirements including annual NMOC re porting requirements and Title V permitting requirements. A dditionally depending on NMOC emission rates, a number of these landfills may also be required to install GCCS despite the fa ct that many of these landfills have been closed for many years and are on the downside of their gas production curve. The EPA concludes lowering the design capacity threshold below 2.0 mi llion Mg would add regulatory requirements with minimal envi ronmental

benefit. The EPA also notes that closed landfills m ay have limited access to additional revenue because they a re no longer collecting tipping fees and the cost for GCCS and r egulatory compliance were not factored into their closure pla ns, they may***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 104 of 324 have poor or incomplete records for estimating land fill gas emissions, and they are less likely to be permitted

. Several commenters from state agencies expressed co ncerns with the permitting and reporting burdens on smalle r landfills and advised the EPA to retain the current design ca pacity threshold. Another state agency noted that MSW land fills with a design capacity greater than 0.38 million m 3 (roughly 15 percent of the current design capacity threshold in the Emi ssion Guidelines) are required to install gas collection and control systems under the state’s HAP rule. In practice, th e smallest landfills controlling under the state regulation ha ve design capacities as low as 0.6 million Mg and 0.4 million m 3 . The commenter noted that the state rule has control req uirements similar to those in the Emission Guidelines, but do es relax some of the monitoring requirements given the lower gas quality and smaller emission potential at older and smaller lan dfills. Two commenters advocated for reducing or eliminatin g the design capacity criteria, referencing the state of California

Landfill Methane Rule 56 (CA LMR), which requires all landfills with at least 450,000 tons of waste-in-place to ass ess whether or not GCCS is required based on other criteria, in cluding

56 California Code of Regulations, title 17, subchapt er 10, article 4, subarticle 6, sections 95460 to 95476, Methane Emissions from Municipal Solid Waste***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 105 of 324 estimated heat input capacity from the landfill gas and surface emissions monitoring data. Based on a review of GCCS data reported in its data set, the

EPA estimates that over 900 landfills in its revise d dataset have installed a GCCS for either voluntary or regul atory reasons. Of these, 17 percent of landfills with a c apacity less than 2.0 Million Mg report having a GCCS installed; 47 percent of landfills with a capacity between 2.0 million Mg and 2.5 million Mg have a GCCS installed; and 76 percent of landfills with a capacity of 2.5 Million Mg or greater have a GCCS

installed. 57 Thus, it appears that a significant number of

landfills have installed GCCS even in the absence o f federal regulation of these smaller sources, based on site- specific circumstances such as gas quality and age of waste in the landfill or areas of the landfill, access to capita l, and energy recovery opportunities. When the EPA promulgated the 2.5 million Mg and 2.5 million

m 3 design capacity threshold in 1996, we considered th e impact on small entities based on public comment (61 FR 99 18, March 12, 1996). Today, small private entities and municipali ties still tend to own smaller sized landfills, whereas larger private entities tend to own larger regional landfills. One commenter

57 See Docket Item “Modeling Database Containing Inpu ts and Impacts for Proposed Review of the MSW Emission Guidelines. 201 5.”***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 106 of 324 noted that reducing the design capacity may disprop ortionately affect local governments and small entities. Based on the ownership data reported in the revised dataset, 78 percent of landfills with a design capacity less than 2.0 mill ion Mg are publicly owned and a similarly strong majority (71 percent) of landfills between 2.0 million Mg and 2.5 million Mg are publicly owned. For landfills with a design capacity of 2.5 million Mg or greater, the share of public ownership drops to 48 percent of landfills. Further, small entity ownership represen ts only approximately 8.7 percent of the landfills requiredto control under a state or federal plan implementing subpart Cc. If the EPA were to reduce the design capacity to 2.0 milli on Mg and 2.0

million m 3 , approximately 730 landfills would be subject to control requirements and 70 (9.8 percent) of those are classified as small entities. If the EPA were to el iminate the design capacity criteria, approximately 749 additio nal existing landfills with a design capacity below 2.0 million Mg (50 percent) would become subject to the rule, of which 379 are classified as small entities, with many of these be ing required to install controls depending on the NMOC level sel ected. Further, the cost burden for installing a collectio n and control system is more significant for small landfills, whi ch are more often owned by small entities, compared to larger l andfills. Because certain costs to construct the gas collecti on system***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 107 of 324 (e.g., flat fees for drill rig mobilization, and mo nitoring and construction costs) remain relatively constant rega rdless of the size of the landfill, the per-acre costs to control a small landfill are more expensive than the per-acre costs to control a large landfill. Assuming an NMOC emission threshold level of 34 Mg/ yr, reducing the design capacity from 2.5 million Mg an d 2.5 million

m 3 to 2.0 million Mg and 2.0 million m 3 would require controls at an additional 20 landfills that have a design ca pacity between 2.0 million and 2.5 million Mg, as shown in Table 3 of this preamble. Requiring controls at landfills in t he 2.0 million to 2.5 million Mg size range would be less cost effective because these landfills have a smaller em ission reduction potential in later years. This is apparen t when considering the percent changes in net control cost s and corresponding emission reductions: net control cost s increase by approximately 1.5 percent, while emission reduction s increase by only 0.5 percent in year 2025.

The EPA does not believe that the additional burden on small entities and the disproportionate impact on p ublicly-owned landfills can be justified in light of the limited additional reduction in overall emissions and is, therefore, n ot proposing any changes to the current design capacity threshol d of 2.5 million Mg and 2.5 million m 3

.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 108 of 324 2. What are the implementation considerations with reducing the

NMOC threshold? For this proposal, the EPA considered two alternati ve NMOC emission thresholds: 40 Mg/yr and 34 Mg/yr. The EPA recognizes that NMOC emissions are site specific, varying wide ly from landfill to landfill and understands that a majorit y of landfills currently affected by the federal and sta te plans implementing the Emission Guidelines conduct Tier 2 testing in

order to refine their NMOC emission estimates befor e installing a GCCS. This proposal also allows a new site-specif ic Tier 4

alternative to determine when a landfill must insta ll a GCCS, as discussed in sections IV.C and VII.A of this preamb le. Despite these variations in NMOC emissions, results from

the model show that a lower NMOC emissions threshol d could accelerate the schedule for installing GCCS at exis ting landfills and also increase the number of existing landfills required to install controls, thereby achieving add itional

reductions of NMOC emissions. The EPA proposed on July 17, 2014 a lower NMOC emis sion threshold in the NSPS (40 Mg/yr) and discussed this alternative in the ANPRM (79 FR 41772) and several nongovernmen tal organizations (NGOs) and a local government entity commented in support of a reduction in the NMOC emission thresho ld. One state agency also provided examples of existing landfills controlling***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 109 of 324

emissions in its state with estimated NMOC emission rates as low as 8.1 Mg/yr. Two commenters expressed concern about whether land fills planning to install controls based on the current t hreshold of 50 Mg/yr would be financially ready to install cont rols at an earlier time. Other commenters expressed concern ab out whether

landfills that have closed and decommissioned their GCCS should be pulled back into control requirements if their e missions fall between the current 50 Mg/yr threshold and a more s tringent NMOC

emission threshold. These commenters recommended th at EPA exempt these landfills from more stringent control require ments. One of the commenters added that it would be costly to re- install or refurbish a previously shutdown system and noted th at the system would likely operate for only a few more years befo re it once again fell below the more stringent NMOC emission t hreshold. Other commenters expressed concerns that lowering t he NMOC threshold would jeopardize carbon credit revenues e xpected from landfills emitting between 40 and 50 Mg/yr NMOC tha t were planning on voluntarily installing a GCCS. A state agency also expressed concern about the additional burden to de legated authorities of managing a larger group of landfills . Another state agency expressed concerns that landfills in a rid areas will have difficulty continuously operating a flare at landfills with lower quality gas that emit between 40 and 50 Mg/yr.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 110 of 324

Another commenter indicated that older and closed l andfills will struggle to maintain continuous operation of their flare at a lower NMOC emission threshold and will need to oper ate the flare with a supplemental fossil fuel. Because of concerns with GCCS operations at landfil ls that have closed, the EPA evaluated whether the lower NM OC thresholds of 34 and 40 Mg/yr should apply to this subset of l andfills, as discussed in section VIII.A of this preamble and pr esented in Table 3 of this preamble. Because of concerns about areas with low gas quality, the EPA is proposing changes to ad dress closed or low-gas-quality areas, including changes to the criteria for capping or removing a GCCS, and providing for the u se of sitespecific surface emissions monitoring measurements to indicate area-specific LFG emissions, as discussed in sectio n VIII.B of this preamble. As shown in Table 3 of this preamble, the increment al cost to control NMOC at open landfills at a threshold of 34 Mg/yr NMOC is $17,000/Mg NMOC and $4.3/mtCO 2 e, compared with $19,300/Mg NMOC and $4.9/mtCO 2 e to control at both open and

closed landfills. As discussed in section V.H of th is preamble, an NMOC threshold of 34 Mg/yr at open landfills wou ld achieve

reductions of 2,770 Mg/year NMOC , and 436,100 Mg/year methane (10.9 million mtCO 2 e) compared to the baseline in year 2025. Commented [A8]: OMB Typographical Comment 3: Reviewer recommends clarifying on page 108 EG t hat the proposed rule would “reduce” methane. As written, it says “achieve” methane. Could also say “achieve methane reductions of...” Response: Text has been edited.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 111 of 324 Based on these considerations, the EPA is proposing to reduce the NMOC emission threshold from 50 Mg/yr to 34 Mg/ yr at open landfills. The EPA is proposing a separate subcateg ory for landfills that closed on or before [insert date of publication in the Federal Register] , as discussed in section VIII.A of this preamble. 3. What are the implementation concerns with shorte ning the initial or expansion lag times? In its revised regulatory options analysis for this proposal, the EPA did not model the impacts from an y regulatory options that reduced the initial or expansion lag t imes. To a great extent, this decision was based on our consid eration of the numerous implementation and cost concerns raise d by SERs and Federalism consultation participants as discussed a t 79 FR

41807 58 , as well as in comments received on the 2014 MSW landfills NSPS proposal and ANPRM for Emission Guid elines (79 FR 41772). Those concerns are summarized below. The in itial lag time is the time period between when the landfill e xceeds the emission rate threshold and when controls are requi red to be installed and started up and the expansion lag time is the

58 See also the docketed report “Summary of Small Ent ity Outreach. 2014.”(Docket Item: EPA-HQ-OAR-2003-0215-0051) [ and the Final Report of the Small Business Advocacy Review Panel on EPA’s Planned Proposed Rul e s - Standards of Performance for Municipal Solid Waste Landfills and Review of Emission Guidelines and Compliance Times for Municipal Solid Waste Landfill s, JuneJuly 2015 ]

.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 112 of 324 amount of time allotted for the landfill to expand the GCCS into

new areas of the landfill. One state agency commented that shortening the curr ent initial lag time would not allow sufficient time to develop and approve the GCCS design plan, obtain the necessary permit, and

construct the GCCS. The commenter added that one un intended consequence of shortening the initial lag time coul d be the inhibition of the beneficial reuse of landfill gas, since a shorter lag time may not allow time to design and a pprove a more complex landfill gas energy recovery system. Commen ters representing affected landfills also expressed conc erns that

current administrative and construction lead times would make shorter lag times difficult. Several landfill owners/operators and a state autho rity agreed with costs and operational and safety concer ns described at 79 FR 41807 associated with increasing the numbe r of wells in active areas as a result of shorter initial or expa nsion lag times. One commenter provided detailed information on costs to install and repair wells in active areas, which the commenter estimated to be between two and three times more ex pensive than wells installed in areas at final grade. This comme nter added that 43 percent of the wells installed during 2014 were replacement wells that had to be installed as a res ult of damage to existing wells resulting from ongoing activities in active***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 113 of 324 areas and noted that shortened lag times would only increase the number of replacement wells required. In addition t o the damage to wells from filling operations, one commenter add ed that vertical wells in active areas require additional l ateral collection pipes to be installed on rather flat slo pes that are susceptible to condensate blockage and must also be replaced more frequently. Similarly, two commenters were con cerned whether horizontal collectors could universally mee t the need for shorter lag times in light of the susceptibilit y of flooding of the horizontal designs and the inability to dewa ter these wells with pumps. Several commenters recognized the benefit of earlie r GCCS installation, but these commenters also discussed a erobic

conditions in active areas and other factors affect ing gas quality that in turn create exceedances of wellheadmonitoring requirements for pressure, temperature, and oxygen/ nitrogen. They noted that few states have accommodated flexib le monitoring alternatives for early collection systems. One stat e authority believed that site-specific factors other than the regulatorydriven lag times, such as safety or odor control, a re already achieving earlier installation of GCCS. Three other commenters urged EPA to include early collection requirements in the proposed Emission Guidelines. One of these commente rs indicated that the requirement to promote early collection co uld be***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 114 of 324 flexible instead of a rigid adjustment to the lag t imes. For the reasons presented in this section as well as those detailed at 79 FR 41807, the EPA is not proposing to shorten th e initial or expansion lag times in the revised Emission Guideli nes. However, the EPA is requesting comment on whether the regula tion should require that the GCCS design plan contain a descrip tion of early gas collection measures or best management practice s, in order for the reviewing professional engineer or the Admi nistrator to

ensure that emissions are minimized. The EPA is als o taking comment on whether the monitoring in the rule shoul d be strengthened to require GCCS to be expanded in a si te-specific manner as long as surface emission monitoring limit s in all areas of the landfill were maintained at all times, similar to the approach taken in the California Landfill Metha ne Rule (LMR). E. How did we select the proposed options? When determining which control options would repres ent BSER, the EPA considered several factors: the imple mentation

considerations identified earlier in this section o f this preamble; and the incremental emission reductions, cost, and cobenefits that would be achieved beyond the baseline

. The EPA compared the annualized net cost and emissi on impacts in 2025 of three different regulatory optio ns to the annualized net costs and emission impacts in 2025 o f the***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 115 of 324 baseline. The EPA analyzed numerous iterations of a lternate control and reporting thresholds and presented pote ntial control options to SERs and Federalism consultation partici pants, as described in section V.D of this preamble. After co nsidering

feedback from the SERs and Federalism consultation participants, as well as comments received on the July 2014 NSPS proposal and ANPRM (79 FR 41772), the EPA selected for considera tion three regulatory alternatives as presented in Table 3 of this preamble. Table 3 summarizes the incremental impact s of each control option, when compared to the baseline. The table shows

the NMOC and methane emission reductions and corres ponding annualized net costs, when using a 7 percent discou nt rate, in

2025.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 116 of 324

Table 3. Emission Reductions and Costs for Control Options in Year 2025 at Existing Landfills (2012$)

Option Lan

dfi lls aff ect ed by pro pos ed opt ion

a No. of lan dfi lls aff ect ed b No. of landf ills contr ollin g No. of land fill s repo rtin g but not cont roll ing Ann ual Net Cos t (mi lli on $20 12) Annu

al NMOC Redu ctio ns (Mg/ yr) Annual Methan e Reduct ions (milli on Mg/yr) Annu

al CO 2 e Redu ctio ns (mil lion mt/y r) c NMOC

cost effect ivenes s ($/Mg) Metha

ne cost effec tiven ess ($/Mg ) CO 2 e cost effect ivenes s ($/mt)

c Baseline Baseli ne (2.5 millio n Mg design capaci ty/50 Mg/yr NMOC) All 989 574 211 299 57,3 00 9.0 226 5,100 32.3 1.3

Incremental values vs. the Baseline Option (2.5 millio n Mg design capaci ty/40 Mg/yr NMOC) Ope

n 0 62 -62 27. 0 1,72 0 0.27 6.8 15,800 100 4.0

All 0 84 120 48. 1 2,50 0 0.39 9.9 19,200 122 4.9

Option (2.5 millio n Mg design capaci ty/34 Mg/yr NMOC) Ope

n 0 106 -106 46. 8 2,77 0 0.44 10.9 17,000 108 4.3

All 0 142 62 77. 6 4,03 0 0.64 15.9 19,300 122 4.9

Option (2.0 millio n Mg design capaci ty/34 Mg/yr NMOC) Ope

n 101 122 -75 51. 0 3,04 0 0.48 12.0 16,800 107 4.3

All 101 162 143 83. 5 4,36 0 0.69 17.2 19,200 122 4.9

a Options in this table show the impacts of reducing the design capacity and/or NMOC emission threshold below baseline level s on open landfills only, and retaining the NMOC threshold of 50 Mg/yr for th e closed landfill***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 117 of 324 subcategory as well as reducing the design capacity and/or NMOC emission thresholds for all landfills (open and closed). b Landfills are affected by the landfills Emission Guidelines based on design capacity. Once affected, they calculate and report emissions until they exceed the NMOC threshold, which triggers control r equirements. c Results do not include secondary CO 2 impacts.

Regulatory options. The EPA considered three regula tory options more stringent than the baseline, as presen ted in Table 3 of this preamble. The first option reduces the NM OC emission threshold to 40 Mg/yr. The second option further re duces the NMOC threshold to 34 Mg/yr. The third option reduce s both the NMOC emission threshold to 34 Mg/yr and the design capacity threshold to 2.0 million Mg and 2.0 million m 3 . We analyzed the impacts of applying each of these three more string ent thresholds to only open landfills as well as all (o pen and closed) landfills. Based on the characteristics of the landfills, betw een approximately 60 and 160 additional landfills wouldbe required

to install controls in 2025. In addition to increas ing the total

number of landfills that would control their emissi ons, the schedule for installing controls would be accelerat ed for many landfills in years prior to 2025 because the landfi ll would exceed the lower thresholds of 34 or 40 Mg/yr NMOC earlier than the baseline, and in turn begin collecting and dest roying landfill gas emissions earlier.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 118 of 324

Emission reductions. If the EPA were to reduce the NMOC emission threshold to 34 Mg/yr at open landfills wh ile retaining the 2.5 million Mg and 2.5 million m 3 design capacity threshold (option 2.5/34) as proposed in this rule, the corre sponding emission reductions in 2025 would be 2,770 Mg/year NMOC and 436,100 Mg/year methane (10.9 million mtCO 2 e) compared to the baseline, which represents a 4.8 percent reduction in emissions beyond the baseline. If EPA were to apply this thre shold to all landfills (open and closed), the corresponding emis sion reductions in 2025 would be 4,030 Mg/year NMOC and 635,100 Mg/year methane (15.9 million mtCO 2 e) compared to the baseline.

Additional reductions could be achieved if the EPA combined the NMOC emission threshold of 34 Mg/yr with a lower de sign capacity threshold of 2.0 million Mg and 2.0 million m 3 (option 2.0/34). The corresponding emission reductions for open land fills in 2025 would be 3,040 Mg/yr NMOC and 479,100 Mg/yr methane (12 million

mtCO 2 e) compared to the baseline for open landfills, representing a 5.3 percent reduction in emissions b eyond the baseline. If the EPA were to apply this lower thres hold for both design capacity and NMOC to all landfills (open and closed), the corresponding emission reductions in 2025 would be 4,360 Mg/year NMOC and 687,100 Mg/year methane (17.2 million mtCO 2 e) when compared to the baseline.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 119 of 324

If the EPA were to reduce the NMOC threshold to 40 Mg/yr at open landfills while retaining a 2.5 million Mg and2.5 million

m 3 design capacity threshold (option 2.5/40), the emi ssion reductions in 2025 would be 1,720 Mg/year NMOC and 270,700 Mg/year methane (6.8 million mtCO 2 e) compared to the baseline. An emission threshold of 40 Mg/yr NMOC with a 2.5 m illion Mg and

2.5 million m 3 design capacity threshold represents approximately a 3 percent reduction in emissions be yond the baseline. If the EPA were to apply the 40 Mg/yr NMO C threshold to all landfills (open and closed), the correspondi ng emission reductions in 2025 would be 2,500 Mg/year NMOC, 270 ,000 Mg/year methane (6.8 million mtCO 2 e) compared to the baseline. The wide range in the magnitude of emission reducti ons among pollutants is due to the composition of landf ill gas: NMOC represents less than 1 percent of landfill gas, whi le methane represents approximately 50 percent. CO 2 e is an expression of

methane in terms of the CO 2 equivalents, given the methane GWP

of 25 59

. Cost. In terms of control costs in 2025, option 2.5 /34 represents an approximately 16 percent increase in control costs

59 IPCC Fourth Assessment Report (AR4), 2007. Climate Change 2007: The Physical Science Basis. Contribution of Working Gro up I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change [Core Writing Team, Pachauri, R.K and Reisinger, A. (eds. )]. IPCC, Geneva, Switzerland, 104 pp.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 120 of 324 compared to the baseline if the threshold were reduced for open

landfills only , and a 26 percent increase in control costs compared to the baseline if the threshold were redu ced for all

landfills (open and closed) . If the EPA adopted a lower NMOC threshold of 34 Mg/yr NMOC along with a reduction i n design capacity to 2.0 million Mg and 2.5 million m 3 , the net cost would increase by 17 percent above the baseline if applying more stringent controls only at for open landfills, and 28 percent

for more stringent control of all landfills (open and closed)

. If the EPA adopted an NMOC threshold of 40 Mg/yr NM OC but retained a design capacity of 2.5 million Mg and 2. 5 million m 3 , the net cost would be 9 percent above the baseline for open landfills and a 16 percent increase for all landfil ls. In terms of cost effectiveness, the overall dollar- per-Mg cost for NMOC reductions under the baseline is $5,1 00 per Mg NMOC and $32.3 per Mg methane as presented in Table 3 of this preamble. Under option 2.5/34, the cost effectivene ss is $17,000 for controlling open landfills and $19,300 for all landfills. If the EPA adopted a lower NMOC threshold of 34 Mg/yr NMOC along with a reduction in design capacity to 2.0 million Mg and 2.0

million m 3 (option 2.0/34), the cost effectiveness is $16,800 for open landfills and $19,200 for all landfills, a lthough the EPA recognizes that this lower cost effectiveness d oes not Commented [A9]: OMB Technical Comment 6: Reviewer recommends clarifying the cost language on pages 117 and 118 EG. As written, it sounds like a fraction of the costs will be borne by “open landfills” and a larger cost for all landfills. Does this mean that “closed” landfills will bear a greater proportion of the costs? Why? Response: See edits here.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 121 of 324 incorporate costs related to additional permitting needs for sources between 2.0 and 2.5 million Mg and m 3 . Under option 2.5/40, the incremental dollar-per-Mg control cost for NMOC reductions is approximately $15,800 per Mg NMOC for open landfills and $19,200 for all landfills. The EPA we lcomes

additional data and comment on the issue of costs. Proposed Option 2.5/34. Based on the emission reduc tion and

cost discussions above and consistent with the Pres ident’s Methane Strategy and the potential to achieve a nea r-term beneficial impact in mitigating global climate chan ge as discussed in section III of this preamble, the EPA is proposing to reduce the NMOC threshold to 34 Mg/yr at open la ndfills but retain the current design capacity threshold of 2.5 million Mg

and 2.5 million m 3 . Lowering the NMOC threshold would result in earlier GCCS installations at landfills already sub ject to the rule based on their design capacity, thereby achiev ing

additional reductions of NMOC and methane. This low ered threshold achieves reductions without adjusting the initial and expansion lag times and incurring the associated co sts and implementation concerns. Reducing the NMOC threshold from the baseline-level of 50 Mg/yr to 34 Mg/yr at open landfills would affect 10 6 more

landfills in 2025 and would achieve an estimated 4. 8 percent

additional reduction in emissions of NMOC and metha ne compared***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 122 of 324

to the baseline. These additional reductions can be achieved at very similar cost effectiveness to an NMOC threshol d of 40 Mg/yr, but a level of 34 Mg/yr would achieve almost 60 percent more reductions than a level of 40 Mg/yr. In addition, the proposal is expected to result in the net reduction of 238,000 Mg CO 2 , due to reduced demand for electricity from the gr id as landfills generate electricity from landfill gas. Reducing the NMOC threshold to 34 Mg/yr results in an incrementa l reduction of methane that is equivalent to approximately 10.9 million

mtCO 2 e per year, which compares to 19 to 33 million mtCO 2 e reductions from the April 16, 2012 regulations for the oil and gas industry (77 FR 49490). In addition, as discussed in section XI.G of this preamble, a level of 34 Mg/yr NMOC als o results in

climate-related benefits associated with methane re ductions. The 2025 methane benefits vary by discount rate and ran ge from about $310 million to approximately $1.7 billion; the mea n SC-CH 4 at the 3-percent discount rate results in an estimate of about $660

million in 2025. Further, this proposal would tighten the control de vice removal criteria, requiring that the controls wouldhave to stay

on until three successive tests for NMOC emissions were below the NMOC emission threshold of 34 Mg/yr instead of 50 Mg/yr,

unless the landfill can demonstrate that its surfac e emissions Commented [A10]: OMB General Comment 15: Reviewer recommends clarifying why EPA is proposing to choose option 2.5/34, which based on the cost comparison tables seems to have the highest cost per Mg NMOC and methane of the options considered. Response: Additional text has been added.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 123 of 324 are low, as discussed in section VIII.B of this pre amble. Depending on the waste-in-place of the landfill at closure and other site-specific factors (e.g., waste compositio n, climate), it may take 15 to 45 years after closure for a larg e modern

landfill to emit less than the NMOC emission thresh old, and in turn qualify for capping or removing the GCCS. Alth ough the emission reductions associated with these later yea rs in the landfills’ lifetimes are not incorporated in the en vironmental and economic impacts of the baseline and options un der consideration in year 2025, the lower threshold ass ociated with this proposal would require controls to be installe d for a longer period than the baseline. Reducing the NMOC threshold also recognizes the opp ortunity to build upon progress to date and achieve even mor e reductions of landfill gas and its components, consistent with the President’s Methane Strategy as discussed in sectio n III of this preamble. Landfill gas generated from established w aste (waste that has been in place for at least a year) is typi cally composed of roughly 50 percent methane and 50 perce nt CO 2 by volume, with less than 1 percent NMOC. Because the components of landfill gas are associated with substantial health , welfare, and climate effects, additional reductions of landf ill gas would improve air quality and reduce health and welfare e ffects associated with exposure to landfill gas emissions. Note that in***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 124 of 324 2013, landfills continued to be the third largest s ource of human-related methane emissions in the U.S., repres enting 15.3 percent of total methane emissions. 60 Methane emissions represent 9.5 percent of all GHG emissions (in CO 2 e) in the U.S. 61 The EPA is not proposing to reduce the design capac ity in conjunction with a reduction in the NMOC emission t hreshold. As discussed in section VI.E of this preamble, this op tion achieves only modest additional reductions (less than one pe rcent more than the proposed option 2.5/34), but has a disprop ortionate impact on small entity- and municipally-owned sites , and closed landfills that are on the downward trend of generat ing landfill gas. Reducing the design capacity would also pose s ubstantial burden on delegated authorities because these small entity- and municipally- owned landfills are not affected by th e currently promulgated NSPS or Emission Guidelines. Alternative Option 2.5/40. The EPA recognizes that the ownership, operating status, and other technical ch aracteristics of individual landfills can affect the site-specifi c cost effectiveness of achieving additional reductions of NMOC and methane and ability to sustain the operation of GCC S that may not be readily apparent when selecting a control op tion based on

60 U.S. EPA. 2013. “Inventory of U.S. Greenhouse Gas Emissions and Sinks: 1990–2013. Executive Summary, ES-8.” Available at http://www.epa.gov/climatechange/ghgemissions/usinv entoryreport.html. 61 Ibid.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 125 of 324 the national aggregate values shown in Table 3 of t his preamble. The EPA is soliciting comment on whether an NMOC th reshold higher than 34 Mg/yr may be appropriate for all, or a subset of the existing landfills affected by this proposal, i n addition to retaining the current threshold of 50 Mg/yr for the closed landfill subcategory, as proposed and discussed in section VIII.A of this preamble. VI. Rationale for the Proposed Changes to Monitorin g, Recordkeeping, and Reporting A. Surface Emissions Monitoring Requirements The intent of the surface monitoring provision in t he existing Emission Guidelines is to maintain a tight cover that minimizes the migration of emissions through the la ndfill surface. Quarterly surface emissions monitoring ind icates whether the cover and gas collection system are wor king properly. In addition to the proposed surface emiss ion provisions discussed here, the EPA is also seeking comment on

additional enhancements to surface emissions monito ring in section X.B of this preamble. Every Cover Penetration. The EPA proposes that all surface penetrations must be monitored for existing landfil ls. Proposed 40 CFR part 60, subpart Cf specifies that the landf ill must “operate the collection system so that the methane concentration is less than 500 parts per million above backgroundat the***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 126 of 324

surface of the landfill. To determine if this level is exceeded, the owner or operator must conduct surface monitori ng around the perimeter of the collection area along a pattern th at traverses the landfill at 30 meter intervals and where visual observations indicate elevated concentrations of landfill gas, s uch as distressed vegetation and cracks or seeps in the co ver and all cover penetrations.” Commenters both supported and opposed monitoring ev ery cover penetration. Several commenters, including tw o state/local agencies and one environmental organization support ed monitoring every cover penetration. The state agency noted tha t seals around penetrations can be compromised as a result of settlement, separation from the barrier layers or b oot materials, and cracking of cover soils tied into pe netrations, thus, leading to detections of landfill gas during surface monitoring as reported by field staff. Several comm enters opposed the requirement to monitor every cover pene tration, citing significant additional cost with no or limit ed environmental benefit. In proposed 40 CFR part 60, subpart Cf, we are reiterating the position in the current regu lation that landfills must monitor all cover penetrations and o penings

within the area of the landfill where waste has bee n placed and a gas collection system is required. Specifically, landfill owners/operators must conduct surface monitoring at 30-meter***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 127 of 324

intervals and where visual observations indicate el evated concentrations of landfill gas. The EPA maintains t hat cover penetrations can be observed visually and are clear ly a place where gas would be escaping from the cover, so moni toring of them is required by the regulatory language. The re gulatory language gives distressed vegetation and cracks as an example of a visual indication that gas may be escaping, but t his example does not limit the places that should be monitored by landfill staff or by enforcement agency inspectors. Thus, co nsistent with the EPA’s historical intent and interpretation, the landfill owner or operator must monitor any openings that ar e within an area of the landfill where waste has been placed an d a gas collection system is required. More Precise Location Data. The EPA is proposing mo re specific requirements for reporting the locations w here measured methane surface emissions are 500 parts per million above background. Since the Emission Guidelines were orig inally promulgated in 1996, EPA is aware of new, relativel y inexpensive monitoring technologies that incorporate GPS techno logies to more precisely identify the location of exceedances . The EPA is aware of several landfills that have been using GPS to more accurately track the location of measurements and s tore these data in databases. The EPA is proposing to require landfills to report the latitude and longitude coordinates of ea ch exceedance***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 128 of 324 using an instrument with an accuracy of at least 3 meters. Coordinates must be in decimal degrees with at leas t five decimal places. This level of accuracy and precisio n is consistent with the requirements proposed in Petrol eum Refinery Sector Risk and Technology Review and New Source Pe rformance Standards (79 FR 36880). This precision will also p rovide more transparency to inspectors reviewing site records o n the location of surface emission leaks, and confirming areas of the landfill where surface monitoring activities were s kipped, which may assist with targeting inspections to problem ar eas of the landfill. In addition, this precision will allow th e landfill to overlay the coordinates of surface exceedances agai nst maps of the GCCS to determine spatial and temporal patterns of exceedances relative to GCCS components. This speci ficity for location data is also being required for landfills using the Tier 4 site-specific measurement approach, as discu ssed in section VII.A of this preamble. B. Wellhead Monitoring Requirements The operational standards of the current Emission Guidelines are to operate each interior wellhead in the collection system with a negative pressure (vacuum) , a landfill gas temperature less than 55 °C and with either a n itrogen level less than 20 percent or an oxygen level less than 5 percent. Since 1996, when the rules were originally promulga ted, the EPA***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 129 of 324 has heard concerns from both regulated entities andimplementing authorities regarding the implementation of the ope rational standards for temperature and oxygen/nitrogen at we llheads. The EPA received feedback during 2013 and 2014 from SER s and Federalism consultation participants expressing con cern that the wellhead standards were overly prescriptive. In the July 17, 2014 proposed NSPS (79 FR 41821) and the ANPRM for the Emission Guidelines (79 FR 41788), the EPA discussed whether these parameters should be adjusted in order to provide m onitoring flexibility for landfills while also ensuring that the GCCS were well operated. The EPA also requested comment on wh at types of landfills may be eligible for adjustments to these wellhead standards; for example, the EPA asked whether only small entities, or landfills with energy recovery project s should benefit from this flexible monitoring. In response to the July 2014 proposed NSPS (79 FR 4 1796) and ANPRM (79 FR 41772), many commenters questionedthe need for the current wellhead operating standards for monito ring pressure, temperature, and oxygen or nitrogen to as sess whether the GCCS was operating effectively. Fire. Industry commenters recognized that the wellh ead operational standards were intended to ensure the l andfill gas collection system is operating properly and to avoi d propagation of a subsurface fire or inhibit anaerobic decomposi tion, but***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 130 of 324 they asserted that the standards achieve neither of the latter objectives. Commenters asserted that the wellhead monitoring pa rameters are poor indicators of landfill fires or inhibited decomposition and impede proper operation of the collection syste m without providing any of the expected benefits. They also e xplained that landfill operators typically respond to high temper ature and oxygen/nitrogen readings by reducing flow from the well or expanding the gas collection system. They explainedthat both approaches can have unintended and harmful conseque nces, including exacerbating a fire, and reducing the col lection efficiency of the GCCS. In addition, they asserted that expanding a GCCS in an area with poor gas quality o r quantity does not assist with achieving additional reduction s. Commenters emphasized the difficulty of meeting the wellhead s tandards in areas of the landfill with declining gas flowrates or gas quality, which is more common in older or closed ar eas of the

landfill. Several commenters stated that landfill o wners already

have inherent incentives to minimize fire risks in order to protect significant investments in GCCS and energy recovery infrastructure. Flooding. Commenters both agreed and disagreed that surface emission monitoring and monthly monitoring of press ure at the

wellhead are sufficient to determine if the well is inoperable***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 131 of 324 or functioning below expected capacity as a result of flooding. Commenters suggested that landfill gas flowrate mea surement is an established technology to assess well performanc e and can be measured without removing the wellhead (unlike meas urement of liquid levels) and added that flow rate measurement is required for landfills affected by the Wisconsin landfills r egulations. The EPA recognizes that this parameter can be measu red using the same equipment used to monitor other wellhead param eters and it is taking comment on whether to monitor this parame ter in section X of this preamble. Wellhead Monitoring and BMPs. In response to the Ju ly 17, 2014 ANPRM (79 FR 41772) and NSPS proposal, the EPA received input indicating that the currently required wellhe ad operating parameters (particularly oxygen/nitrogen and temper ature), are barriers to, rather than a part of, a “well operate d” GCCS and prevent proactive LFG collection practices such as connecting the GCCS to the leachate collection system and inst alling horizontal or other early gas collectors. Specifica lly, the EPA received information explaining that leachate syste ms are not designed to be air tight and are not constructed in refuse. The

information also indicated that when leachate colle ction systems contain liquids, the piping that conveys the leacha te may be unable to collect enough gas until the liquid is re moved and that as a result, when a vacuum is applied, ambient air can be***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 132 of 324 pulled in as well, leading to elevated oxygen conce ntrations. Accordingly, an alternative operating procedure wou ld be needed to accommodate these higher oxygen levels. The info rmation received indicates that regulatory agencies have be en reluctant to grant these alternatives. It was also pointed out that gas quality and quanti ty can vary widely from different systems and at different times within the same system, which is why horizontal collectors and leachate system components are not designed to meet the 40 C R part 60, subpart Cc and WWW operating parameters for pressur e, temperature, and nitrogen/oxygen concentration. Inf ormation from a state agency indicated that some intake of ambien t air is likely with leachate collectors and suggested that operators should have flexibility to decide the balance betwe en gas flow and oxygen intake and on whether to cease extractin g landfill gas or use another method. The information providedfurther indicated that the time delay associated with modif ying a GCCS design plan or getting approval for higher operatin g values (HOVs) is problematic when applied to collector pip es used for seep and odor control, since operators must make th ese changes more quickly for safety reasons. The EPA also received input explaining the benefits of early gas collection, such as fewer emissions and r educed odors.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 133 of 324

Corrective Action Concerns. Under the current rules , if a landfill exceeds a wellhead operating parameter, th e landfill owner or operator must initiate corrective action w ithin 5 days and follow the timeline in 40 CFR part 60, subparts WWW and Cc for correcting the exceedance. If the exceedance ca nnot be corrected within the specified timeframe, the landf ill owner/operator should prepare to expand the GCCS. A s commenters note above, exceedances involving elevated temperat ure and oxygen/nitrogen concentration are often not solved by expanding the GCCS, especially in older areas. Several indust ry commenters, as well as a state regulatory agency, n oted that wellhead corrective action often requires very site -specific and technical solutions other than expanding a GCCS andit is not reasonable to develop these actions and have them a pproved

within the narrow timeframes allowed in the current rules. A

trade association noted that most landfills have oc casional exceedances of wellhead standards and that requests for HOVs are among the top five paperwork items submitted for la ndfill GCCS operations. Given the numerous landfills subject to control requirements as well as the fact that many landfill s could have more than 100 wells installed, the trade associatio n also noted that the prescriptive review and approval processes for HOV of wellhead operating standards present a significant burden for***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 134 of 324 both the landfill and the delegated authority witho ut an

environmental benefit. Commenters representing industry, state government, the SBA Office of Advocacy, and a trade organization calledon the EPA to remove temperature and oxygen/nitrogen wellhead operating parameters from Emission Guidelines for all landfil ls. These commenters were all in agreement that negative pres sure and surface monitoring can assure proper GCCS operation . One commenter noted that landfills with energy recovery projects will continue to monitor wellhead parameters to ens ure proper equipment operation and maximize revenue from energ y sales, without requiring the monitoring and reporting of t hese parameters under the Emission Guidelines. Another c ommenter noted that the regulations should provide some flex ibility to

accommodate declining gas generation that facilities will experience as a result of local diversion initiativ es. Two state agencies requested that the wellhead oper ating parameters of temperature and oxygen/nitrogen merel y serve as guidance to provide flexibility, particularly to sm all entities. One of the commenters provided an example of monito ring requirements in its state regulation, which exempts supplemental and/or temporary odor and gas control system compon ents (e.g., leachate cleanouts, leachate recirculation, early c ollectors) from pressure, temperature, and oxygen/nitrogen lim its. In this***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 135 of 324 case, the state does not impose limits for these pa rameters, but it does require the landfill to monitor those param eters. Two commenters requested that temperature and oxygen/nitrogen monitoring requirements be continue d while maintaining current surface methane monitoring meth ods. A state agency noted that wellhead monitoring can identify subsurface biological and chemical reactions that can present a safety hazard and cannot be detected by surface emission m onitoring only. An environmental organization explained that wellhead monitoring provides indicators of conditions that c ould lead to subsurface fires, release massive volumes of HAP, a nd cause terrible odors and was concerned that removing thes e requirements prevents the landfill and the implemen ting authorities from identifying early indicators of po tential problems. The commenter explained that landfill own ers may have difficulty meeting the requirements due to improper site management and failure to maintain tight seals, lea ding to too much air intake. One city also advocated for more s tringent monitoring in order to more proactively identify od ors or other operational concerns with a GCCS. Based on public comments, input from small entities , and our own analysis of available information, the EPA is proposing to remove the requirement to meet operational stand ards for temperature and nitrogen/oxygen at wellheads and is thus also***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 136 of 324 proposing to remove the corresponding requirement f or corrective action for exceedances of these parameters. To ensu re a welldesigned and well-operated GCCS that minimizes surf ace emissions, the EPA is proposing to use a combinatio n of GCCS design and approval requirements as discussed in se ction VI.C of this preamble, landfill surface emission monitoring requirements as discussed in section VI.A of this preamble, and continued maintenance of negative pressure at wellheads. Base d on the feedback provided by commenters and our analysis of available information, the EPA believes these adjustments pro vide more flexibility to landfills, can result in additional reductions of LFG emissions from other GCCS components, and will reduce the

burden of corrective action on both the landfill ow ner/operator and the implementing authority. Based on public inp ut, the EPA expects that eliminating the operational standards for oxygen/nitrogen and temperature will drastically re duce the number of requests for HOVs and alternative timelin es for making corrections while ensuring that the gas collection and control system continues to operate properly. The procedure s for approving HOVs for wellheads not demonstrating comp liance with the negative pressure standard are discussed in sec tion VI.D of this preamble. While the EPA is proposing to remove the requiremen t to meet operational standards for temperature and nitr ogen/oxygen,***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 137 of 324 the EPA is proposing that landfill owners/operators continue monthly monitoring and recordkeeping of the wellhea d temperature and oxygen/nitrogen values, consistent with operati onal guidance documents and best practices for operating a GCCS i n a safe and

efficient manner. 62,63 Based on our evaluation of commenters’ concern that the oxygen/nitrogen and temperature op erational standards can be a limiting factor in promoting ear lier and more robust collection of LFG, the EPA is proposing to n o longer require the landfill to take corrective action if t he monitoring of these parameters demonstrates that a particular value or values is/are exceeded. The EPA is proposing that l andfill owners and operators continue monitoring these para meters because, as several industry commenters and regulat ory agencies stated, the measurement of these parameters can sti ll serve as useful guidance for landfill operators and landfill gas energy project operators because they assess GCCS performa nce and thus help to periodically adjust or “tune” the GCCS to m inimize LFG emissions and maintain safe operating conditions at the landfill. The equipment used to monitor wellheads c ommonly includes these parameters, so these parameters can be measured at the same time the technician monitors wellhead p ressure without imposing additional burden. The results of this monthly

62 http://www.epa.ohio.gov/portals/27/engineer/eguide s/guide78.pdf 63 http://www.nrel.gov/docs/legosti/fy97/23070.pdf***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 138 of 324 wellhead monitoring will now be kept as records on site because

the EPA continues to believe these data will be use ful for implementing authorities when approving modificatio ns to the original GCCS design plan, or when conducting inspe ctions of the

site. The requirement to maintain negative pressure at ea ch wellhead ensures that gas is being routed to a GCCS that was designed and built in accordance with a GCCS design plan that has been approved by a professional engineer. The E PA believes these wellhead standards, together with the surface emission monitoring requirements, are effective and limit th e possibility of surface emissions of LFG. This approach also all ows landfills and state regulators the time and flexibility to de termine the appropriate response for adjusting wellfield operat ions, as needed, without imposing overly prescriptive requir ements. This approach also provides increased flexibility for la ndfills to install supplemental and temporary gas collection c omponents to

achieve additional reductions of LFG without the ri sk of exceeding oxygen/nitrogen or temperature operationa l standards. C. Requirements for Updating the Design Plan The EPA is proposing criteria for when an affected source must update its design plan and submit it to the implementing authority for approval. We are proposing that a rev ised design plan must be submitted as follows: (1) Within 90 da ys of***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 139 of 324 expanding operations to an area not covered by the previously approved design plan, and (2) prior to installing o r expanding the gas collection system in a manner other than as described in a previously approved design plan. The EPA is proposing site-specific design plan revi ew and approval procedures that recognize the unique site- specific topography, climate, and other factors affecting th e design of the GCCS. However, the EPA solicits comment on ways to streamline the design plan submission and approval procedures as part of its review of the Emission Guidelines. Examples of streamlining may include the potential development of a process by which approved alternative operating parameters could be automatically linked to updates of design plans or development of a process by which alternative operating paramet ers and updated design plans could be approved on a similar schedule. D. Submitting Corrective Action Timeline Requests We have included provisions in proposed 40 CFR part 60, subpart Cf (40 CFR 60.36f(a)(3)) to clarify our int ent that agency approval of corrective action timelines is r equired only if a landfill does not fix an exceedance in 15 days and is unable to or does not plan to expand the gas collec tion system within 120 days. The EPA is clarifying that “expans ion” of the GCCS means a permanent change that increases the ca pacity of the GCCS, such as increasing the size of header pipes, increasing***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 140 of 324 the blower sizes and capacity, and increasing the n umber of wells. Excluding system expansion, all other types of corrective actions expected to exceed 15 calendar days should be submitted to the agency for approval of an alternate timeline . In addition, if a landfill owner or operator expects t he system expansion to exceed the 120-day allowance period, i t should submit a request and justification for an alternati ve timeline. We have not proposed a specific schedule for submit ting these requests for alternative corrective action timeline s because investigating and determining the appropriate corre ctive action, as well as the schedule for implementing the correc tive action, will be site specific and depend on the reason for the exceedance. We clarify that a landfill should submi t an alternative timeline request as soon as possible (i .e., as soon as the owner or operator knows that it would not be able to correct the exceedance in 15 days or expand the sys tem in 120 days) to avoid being in violation of the rule. If t he landfill were to wait until 120 days after the exceedance to submit an alternative timeline, then by the time the regulato ry agency has

the chance to review the timeline and determine if it is approvable, the landfill will already be in violati on of the requirement to expand the system within 120 days. A fter submitting the alternative timeline request, the la ndfill should work with its permitting authority to communicate t he reasons***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 141 of 324 for the exceedances, status of the investigation, a nd schedule

for corrective action. To address implementation concerns associated with the time allowed for corrective action, the EPA requests comment on an alternative that extends the requirement for notifi cation from 15 days to as soon as practicable, but no later tha n 60 days from when an exceedance is identified. Many request s for an alternative compliance timeline express the need fo r additional time to make necessary repairs to a well that requi res significant construction activities. Extending the time period to as soon as practicable, but no later than 60 day s, may reduce the burden associated with the approval of an alter native

timeline and ensure sufficient time for correction without significant environmental detriment. If the EPA wer e to extend the time period to as soon as practicable, but no l ater than 60 days, then the EPA is also considering the removal of the provision to submit an alternative timeline for cor recting the exceedance. Thus, by no later than day 60, the land fill would have to either have completed the adjustments and r epairs necessary to correct the exceedance, or be preparedto have the system expansion completed by day 120. The EPA is a lso requesting input on whether 60 days is the appropri ate amount of time to allow owners or operators to make the neces sary repairs. E. Electronic Reporting***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 142 of 324 In this proposal, the EPA is describing a process t o increase the ease and efficiency of performance tes t data submittal while improving data accessibility. Speci fically, the EPA is proposing that owners and operators of MSW l andfills submit electronic copies of required performance te st and performance evaluation reports by direct computer-t o-computer electronic transfer using the EPA-provided software . The direct computer-to-computer electronic transfer is accompl ished through the EPA’s Central Data Exchange (CDX) using the Compliance and Emissions Data Reporting Interface (CEDRI). The CDX is the EPA’s portal for submittal of electronic data. The EPA-pr ovided software is called the Electronic Reporting Tool (E RT), which is used to generate electronic reports of performance tests and evaluations. The ERT generates an electronic report package that will be submitted using the CEDRI. The submitted re port package will be stored in the CDX archive (the official cop y of record) and the EPA’s public database called WebFIRE. All s takeholders will have access to all reports and data in WebFIRE and accessing these reports and data will be very strai ghtforward and easy (see the WebFIRE Report Search and Retriev al link at http://cfpub.epa.gov/webfire/index.cfm?action=fire. searchERTSubm ission). A description and instructions for use of the ERT can be found at http://www.epa.gov/ttn/chief/ert/index. html, and CEDRI can be accessed through the CDX Web site at***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 143 of 324 www.epa.gov/cdx. A description of the WebFIRE datab ase is

available at http://cfpub.epa.gov/oarweb/index.cfm?action=fire.m ain. The proposal to submit performance test data electr onically to the EPA applies only to those performance tests conducted using test methods that are supported by the ERT. T he ERT supports most of the commonly used EPA reference me thods. A listing of the pollutants and test methods supporte d by the ERT is available at http://www.epa.gov/ttn/chief/ert/in dex.html. We believe that industry would benefit from this pr oposed approach to electronic data submittal. Specifically , by using this approach, industry will save time in the perfo rmance test submittal process. Additionally, the standardized f ormat that the ERT uses allows sources to create a more comple te test report resulting in less time spent on data backfil ling if a source failed to include all data elements requiredto be submitted. Also through this proposal, industry may only need to submit a report once to meet the requirements of th e applicable subpart because stakeholders can readily access the se reports from the WebFIRE database. This also benefits indus try by cutting back on recordkeeping costs as the performa nce test reports that are submitted to the EPA using CEDRI a re no longer required to be retained in hard copy, thereby, redu cing staff

time needed to coordinate these records.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 144 of 324 Since the EPA will already have performance test da ta in hand, another benefit to industry is that fewer or less substantial data collection requests in conjunction with prospective required residual risk assessments or t echnology

reviews will be needed. This would result in a decr ease in staff time needed to respond to data collection requests. State, local, and tribal air pollution control agen cies will also benefit from having electronic versions o f the reports they are now receiving because they will be able to conduct a

more streamlined and accurate review of electronic data submitted to them. For example, the ERT would allowfor an electronic review process, rather than a manual dat a assessment, making review and evaluation of the source provided data and

calculations easier and more efficient. In addition , the public will also benefit from electronic reporting of emis sions data

because the electronic data will be easier for the public to access. How the air emissions data are collected, a ccessed, and reviewed will be more transparent for all stakehold ers. One major advantage of the proposed submittal of performance test data through the ERT is a standard ized method to compile and store much of the documentation requ ired to be reported by this rule. The ERT clearly states what testing information would be required by the test method an d has the***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 145 of 324 ability to house additional data elements that migh t be required by a delegated authority. In addition, the EPA must have performance test dat a to conduct effective reviews of Clean Air Act section 111 standards, as well as for many other purposes, incl uding compliance determinations, emission factor developm ent, and annual emission rate determinations. In conducting these required reviews, the EPA has found it ineffective and time consuming, not only for us, but also for regulatory agencies and source owners and operators, to locate, collect, an d submit performance test data. In recent years, stack testi ng firms have typically collected performance test data in electr onic format, making it possible to move to an electronic data su bmittal system that would increase the ease and efficiency of data submittal and improve data accessibility. A common complaint heard from industry and regulato rs is that emission factors are outdated or not represent ative of a particular source category. With timely receipt and incorporation of data from most performance tests, the EPA would be able to ensure that emission factors, when updat ed, represent the most current range of operational practices. Fi nally, another benefit of the proposed data submittal to W ebFIRE electronically is that these data would greatly imp rove the overall quality of existing and new emissions facto rs by***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 146 of 324 supplementing the pool of emissions test data for e stablishing

emissions factors In summary, in addition to supporting regulation development, control strategy development, and othe r air pollution control activities, having an electronic database populated with performance test data would save ind ustry, state/local/tribal agencies, and the EPA significan t time, money, and effort while also improving the quality of emission inventories, air quality regulations, and enhancing the public’s access to this important information. VII. Rationale for Proposed Alternative Emission Th reshold Determination Techniques The EPA is proposing an emission threshold determin ation based on site-specific surface emissions monitoring (SEM) that provides flexibility for when a landfill must insta ll and operate a GCCS. If the owner or operator limits lan dfill surface

methane emissions and can demonstrate that those em issions are below 500 ppm methane for 4 consecutive quarters, t hen the requirement to install a GCCS is not triggered even though estimates using Tiers 1, 2, and/or 3 may show that the

landfill’s annual NMOC emissions have exceeded the regulatory threshold. In addition, the Tier 4 surface emission approach

could also be used as one of the criteria for deter mining when a GCCS can be removed or partially removed or decommi ssioned at***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 147 of 324

closed landfills or closed areas of active landfill s, as discussed in sections IV.D and VIII.C of this pream ble. The idea to measure site-specific surface emissions to help determine the timing of GCCS installation was prese nted while the EPA was conducting outreach with small entities during its review of the landfills regulations in 2014. Small entities

recommended a new Tier 4 surface emission demonstra tion to allow increased flexibility for landfills that exceed mod eled NMOC emission rates to demonstrate that site-specific me thane emissions are actually low prior to being required to install a GCCS. In addition, the Environmental Defense Fund ( EDF) presented the idea of a surface concentration thres hold as one of many potential alternatives to increase emission reductions from landfills in its January 2013 whitepaper. 64 The EPA presented and solicited comments on potential Tier 4 procedures in both the NSPS proposal for new landfills and the ANPRM for existing landfills (79 FR 41772). Many commenters, representing both industry and environmental interests, supported the Tier 4 SEM a pproach for determining when a GCCS must be installed. These co mmenters stated that the option to conduct site-specific mea surements

64 Environmental Defense Fund. Recommendations and Co nsiderations for EPA’s Forthcoming Revisions to Section 111 Standards for MSW Landfills. January 2, 2013. See EPA-HQ-OAR-2003-0215-0050.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 148 of 324 using SEM is a more accurate indication of when gas collection is necessary to reduce emissions, compared to model ed emission rates. However, one commenter on the NSPS proposed rule opposed the inclusion of a Tier 4 option for new landfills, stating that it allows a subset of new landfills to delay methan e capture requirements when these landfills will be required to install a GCCS in the future and should have a GCCS designed and installed during landfill construction. Other commenters expr essed concern about state agencies lack of experience and time to determine whether Tier 4 monitoring requires a GCCS to be ins talled and requested guidance for Tier 4 implementation proced ures. Many commenters identified the potential benefits o f a Tier 4 option. Commenters representing both industry and environmental interests noted that the SEM option w ill encourage landfill owners and operators to implement methane reduction practices, such as the use of oxidative landfill co vers, organic waste diversion, and interim gas control measures ( horizontal gas collectors, connecting a leachate collection re covery system into a GCCS), noting that such practices can be imp lemented more quickly and more cost-effectively than a GCCS insta lled in accordance with the design plan requirements of the current Emission Guidelines. Commenters indicated that a SE M method reflects actual site-specific emissions data that a ccount for gas generation differentials attributed to climate variations,***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 149 of 324 waste acceptance rates, and cover soil materials th at vary between landfills in different regions of the U.S. One commenter indicated that the use of SEM in determining the ne ed to install a GCCS would reduce costs and energy consumption fo r landfills otherwise required to install controls, that would not generate a sufficient amount of gas to support a collection system but

would remain below surface emission thresholds base d on sitespecific measurements. Another commenter added that a Tier 4 approach grants additional flexibility and a potent ial cost savings compared to the Tier 2 method, but cautione d that a surface monitoring methodology needs to be develope d that is functional during windy conditions. Commenters also considered how to implement a Tier 4 approach, including the hierarchy of the new tier r elative to the existing tiers, procedures for conducting the S EM, the level of the appropriate exceedance, and what to do upon an exceedance. Several commenters suggested that Tier 4 could be employed at any point following a Tier 1 or Tier 2 test where the calculated NMOC emission rate is greater than t he NMOC threshold for installing a GCCS. These same comment ers suggested that landfill owners and operators have the option to perform Tier 4 SEM testing in the same areas and using the same methods currently established in 40 CFR part 60, subpart WWW. These

commenters recommended that if an exceedance occurs during Tier***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 150 of 324 4 SEM testing, then landfill owners and operators s hould follow the same procedures and timelines for remediation a nd remonitoring as outlined in subpart WWW. These commen ters further suggested that if an exceedance cannot be remediate d under the existing subpart WWW procedures, then the landfill would be required to prepare a GCCS design plan within 1 yea r of the

initial exceedance and install a GCCS within the mo nitored area

within 30 months of the initial exceedance. These c ommenters further suggested that if during the initial monito ring event methane surface emissions do not exceed 500 ppm ove r background, then the installation of a GCCS is not required androutine SEM should be performed until the landfill or area of t he landfill is closed. One commenter requested that the EPA pro pose a surface concentration level of 200 ppm and indicate d that this level provides empirical confirmation that the land fill is ready

to install a GCCS. After considering public comments and input from sm all entity outreach, the EPA is proposing Tier 4 SEM pr ocedures for determining when a landfill must install a GCCS. Ti er 4 allows landfill owners and operators to demonstrate that s ite-specific surface methane emissions are low. Under Tier 4, as proposed in this proposed rule, if the site-specific surface me thane emissions are below 500 ppm for 4 consecutive quart ers, then the requirement to install and operate a GCCS has not b een triggered***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 151 of 324

even in circumstances where emission estimates usin g Tiers 1, 2, and/or 3 are above the regulatory threshold. Howeve r, any quarterly surface emissions value over 500 ppm woul d trigger the requirement to install and begin operating a GCCS. If the landfill opts to use Tier 4 for its emission thresh old determination and there is any measured concentrati on of methane of 500 parts per million or greater from the surfac e of the landfill, the owner or operator must install a GCCS , and it cannot go back to using Tiers 1, 2 or 3. The landfi ll owner or operator would be required to submit a design plan within 1 year of reporting the surface emissions value over 500 p pm to the implementing authority in an annual report and woul d be required to install and start up a GCCS within 30 months of reporting the surface emissions value over 500 ppm. The SEM demonstration would be conducted using the SEM procedures described in sections IV.B and VI.A of t his preamble. SEM would be conducted around the perimeter of the landfill and the required traverse every 30 meters for the entir e landfill. Note that the EPA is requesting comment on enhancedsurface monitoring, including the 30 meter traverse pattern , in section X.B of this preamble. The Tier 4 provisions can be utilized by any landfill that has exceeded the design capacity threshold. The Tier 4 provisions provide an incentive for a la ndfill***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 152 of 324 owner/operator to keep surface emissions low as des cribed later

in this section. Under this proposal, if a landfill exceeds the mode led NMOC emission rate under Tier 1, then the landfill may c hoose to estimate the NMOC emission rate by using the Tier 2 or 3 procedures or measure actual surface emissions usin g Tier 4. If a landfill failed a Tier 4 test, the landfill wouldtrigger the requirement to submit a design plan and to install and operate a GCCS. However, if a landfill failed a Tier 2 or 3 t est, proposed 40 CFR part 60, subpart Cf allows the landfill to t est using a “higher” tier, including Tier 4. For example, if a landfill exceeds the proposed NMOC emission rate of 34 Mg/yr using Tier 2, then the landfill may choose to calculate the NM OC emission rate using Tier 3, or the landfill may choose to de monstrate that site-specific surface methane emissions are be low 500 ppm using Tier 4. Tier 1 is the most conservative metho d for estimating NMOC emissions and models NMOC emissions based on default values for methane generation rate (k), met hane generation potential (Lo), and NMOC concentration ( C NMOC ). Tier 1 takes the least effort and expense to conduct, but tends to overestimate NMOC emissions given the conservative default parameters. A landfill would likely use Tier 1 for its initial

estimate of NMOC emissions. Tier 2 models NMOC emis sions based on the same default values for methane generation r ate and***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 153 of 324 methane generation potential, which are in turn bas ed on waste composition and climate data, but allows the landfi ll owner/operator to determine a site-specific NMOC co ncentration. Under Tier 2, landfills would incur a more substant ial cost to determine the site-specific NMOC concentration. Tie r 3 also models NMOC emissions, but adds another site-specif ic measurement for a methane generation rate using Met hod 2E. Under Tier 3, landfills would incur a substantial cost to determine the site-specific methane generation rate. Industry experience and public comments indicate that sites do not freq uently use Tier 3 because of the expense. Commenters stated th at the Tier 3 test is extremely rare because of the high cost andthe fact that in many geographical areas the “k” factor (met hane generation rate constant) is not reduced via testin g. There are a significant number of landfills reporting under t he Tier 2 method, which allows the site to measure a site-spe cific NMOC concentration instead of using the higher default N MOC concentrations required under the Tier 1 calculatio ns, however, Tier 3 is not widely used. Thus, we are proposing t o allow landfills to conduct Tier 4 testing after a failed Tier 1, Tier 2, or Tier 3 test. A landfill owner or operator may undertake Tier 4 S EM testing upon submitting an annual NMOC emission rat e report that shows an NMOC emission rate greater than 34 Mg/yr u sing Tier 1,***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 154 of 324 2, or 3 procedures. If the landfill owner or operat or chooses to undertake Tier 4 SEM instead of submitting a design plan and installing and operating a GCCS or estimating the N MOC emission rate using the next higher tier, then the landfill owner or operator would begin keeping records of all Tier 4 SEM readings and submit a “Tier 4 SEM report” as its next annual report. The report would include and identify the number of SEM readings above 500 ppm. If the report shows any SEM readings above 500 ppm methane, then the landfill would be required to submit a GCCS design plan within one year and install and be gin operating a GCCS within 30 months. (The landfill could not ta ke corrective

action to correct the Tier 4 exceedance and could n ot estimate the annual NMOC emission rate using Tiers 1, 2, or 3.) If the Tier 4 SEM report shows no SEM readings abov e 500 ppm for 4 consecutive quarters, then the landfill m ay continue Tier 4 monitoring at a reduced semi-annual frequenc y or return to Tier 1, 2, or 3. This approach allows owners andoperators some flexibility to select the tier that is most ap plicable to their landfill, based on the point each landfill is in its lifecycle, and other site-specific factors. Note th at a landfill can recalculate NMOC using Tiers 1, 2, or 3 only if it has 4 consecutive quarters with no SEM readings above 500 ppm. The EPA selected a 500 ppm threshold for Tier 4 bec ause it

is consistent with the level the EPA determined to be***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 155 of 324 appropriate to demonstrate that a GCCS is well-desi gned and well operated. In other words, when conducted properly, SEM is a good indicator of how well a GCCS is operating overall. For landfills without a GCCS (including those that may be using o ther LFG mitigation strategies), the level of 500 will demon strate that site-specific surface methane emissions are as low as those allowed at a landfill with a well-operated and well -designed GCCS in place. See the docketed memorandum “Establi shing a SiteSpecific Emission Threshold Alternative for MSW Lan dfills,

2015.” Therefore the EPA believes this alternative site-specific concentration threshold will achieve the goal of mi nimizing methane emissions to the atmosphere. The EPA is awa re that the surface emission threshold for installing a GCCS un der the CA LMR is 200 ppm. However, the EPA also notes that CA LMR retains the 500 ppm level as an appropriate level for insta ntaneous SEM readings for areas already controlled by a GCCS. Ca lifornia ARB initially proposed a 200 ppm SEM threshold for both GCCS installation and for GCCS operation in its regulati on, but finalized 500 ppm for GCCS operation because a lowe r threshold could cause an operator to overdraw the vacuum on t he GCCS (to avoid a surface exceedance), which in turn could dr aw in too much oxygen and possibly cause fires. The EPA recog nizes the concerns with setting the threshold too low, which may cause operators of voluntary GCCS to overdraw the vacuum on the GCCS,***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 156 of 324 and has proposed a level of 500 ppm. The EPA reques ts comment on whether a level between 200 and 500 ppm is appropri ate for the Tier 4 provisions, and whether setting the level be low a specific point in this range poses fire or other sa fety concerns for operating a GCCS. The EPA also requests data th at might support a different surface emissions threshold. The EPA requests comments on whether landfill owner s and operators should provide notification to EPA when c onducting Tier 4 surface emissions monitoring. Such notificat ion would be similar to the performance test notification requir ed by 40 CFR 60.8(d), wherein the owner or operator of an affect ed facility provides the Administrator at least 30 days prior n otice of any performance test to afford the Administrator the op portunity to have an observer present. As noted earlier in this section, commenters repres enting both industry and environmental interests noted tha t the Tier 4 SEM option would encourage landfill owners and oper ators to implement alternative methane reduction practices, such as the use of oxidative landfill covers, interim gas contr ol measures, and organic waste diversion. The EPA agrees. Such m easures can directly affect surface emissions and when employedwould help a landfill ensure that surface emissions are low, ena bling a landfill to delay the regulatory requirement to ins tall a GCCS without a significant negative impact on public hea lth or the***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 157 of 324 environment. Section V.A of this preamble discusses alternative methane reduction practices, such as the use of oxi dative landfill covers, interim gas control measures, and organic waste

diversion. VIII. Proposed Changes to Address Closed or Non-Pro ducing Areas The EPA recognizes that many landfills or landfill areas are closed or have inactive areas that do not produ ce as much landfill gas. The production of landfill gas natura lly declines over time as an area stops accepting waste and the amount of degradable organic content declines. In the ANPRM f or the Emission Guidelines (79 FR 41772), the EPA requeste d input on ways to ensure emissions are minimized in the later stages of a landfill’s lifecycle (79 FR 41783). Specifically, t he EPA sought input on whether the current criteria for capping o r removing a GCCS are appropriate: (1) The landfill is closed, ( 2) the GCCS has been in operation for 15 years, and (3) three s uccessive

tests for NMOC emissions are below the NMOC emissio n threshold. We also sought input on alternative approaches to d etermining when it is appropriate to cap or remove a GCCS, suc h as consecutive quarterly measurements that would demon strate that

surface emissions are low. A. Subcategory for Closed Landfills The EPA notes that many existing landfills in our d ataset closed at various points since 1987, including land fills that***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 158 of 324 closed as many as 18 years prior to today’sthis proposed action. In the ANPRM, the EPA presented the distribution of existing landfills by closure date (see Table 3, 79 FR 41792 ). These data showed that nearly 80 percent of the existing landf ills with a design capacity of at least 2.5 million Mg and 2.5 million m 3 were active landfills as of 2014. Similarly, 77 per cent of the cumulative waste disposed in these existing landfil ls were at active landfills. The EPA recognizes that these act ive landfills are the most significant sources of landfill gas em issions at existing landfills.

The EPA evaluated the costs and benefits of control ling emissions at a level between 34 Mg/yr and 40 Mg/yr at both open

and closed landfills. Table 3 of section V.E of thi s preamble presents the number of landfills affected and the c orresponding

emission reductions and costs. The EPA also conside red how closed landfills would be affected by this proposal . We are considering “closed” landfills to be those that clo sed after 1987 but on or before the date of this proposal. At the baseline NMOC emission threshold of 50 Mg/yr , the

EPA estimates that 29 of the 233 closed landfills w ith a design capacity of at least 2.5 million Mg and 2.5 million m 3 would be required to install controls. At an NMOC emission t hreshold of 40 Mg/yr, the EPA estimates that an additional 22 l andfills beyond the baseline would be required to install co ntrols,***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 159 of 324 resulting in controls at approximately 51 65 closed landfills in 2025. The landfill gas controlled at these 51 close d landfills represents approximately 6 percent of the total emi ssion

reductions achieved from all active and closed land fills expected to control emissions at a level of 40 Mg/y r NMOC in year 2025. At the proposed NMOC emission threshold of 34 Mg/yr,

the EPA estimates that an additional 36 landfills b eyond the baseline would be required to install controls, res ulting in controls at approximately 65 66 closed landfills in 2025. The landfill gas controlled at these 65 closed landfill s represents less than 7 percent of the total emission reduction s achieved from all active and closed landfills expected to co ntrol emissions at a level of 34 Mg/yr NMOC in year 2025. An NMOC emission rate threshold of 34 Mg/yr NMOC at closed landfills would achieve an additional 1,260 Mg NMOC and 5

million mtCO 2 e as compared to retaining the threshold of 50 Mg/yr NMOC for these closed sites. These reductions would be

achieved at an incremental control cost effectivene ss of $23,700 per Mg NMOC and $6 per mtCO 2 e for closed landfills in 2025 (excluding additional testing and monitoring costs)

. See the docketed memorandum “Revised Cost and Emiss ion Impacts Resulting from the Landfill EG Review (2015 )” for

65 22 closed landfills plus 29 closed landfills 66 36 closed landfills plus 29 closed landfills Commented [A11]: OMB Technical Comment 7: Reviewer recommends clarifying that the additional 22 and additional 36 landfills referred to on page 156 EG are all closed landfills. Response: Clarifying text has been added as a footnote.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 160 of 324 additional detail on the impacts on closed landfill s. In addition to these control costs, the EPA estimates that 160 closed landfills that are not controlling in 2025 w ould be required to estimate and report NMOC emissions unde r the proposed option because they have a design capacity of at least 2.5 million Mg and 2.5 million m 3

. After closure, the gas flows at landfills decline a nd the ability to achieve additional reductions also decli nes. The EPA received input from SERs that many closed landfills supplement their flare with pilot (fossil) fuels in order to m aintain flare operation despite declining gas quantities and qual ity. These

SERs were concerned that a lower threshold at these closed landfills would extend the amount of pilot fuel nec essary for flame stability. The EPA notes that closed landfill s may have limited access to additional revenue because they a re no longer collecting tipping fees and the cost for GCCS and r egulatory compliance were not factored into their closure pla ns. Further, many SERs expressed concerns that many compliance c osts are fixed cost items, regardless of the operating statu s of the landfill, such as permitting fees, drill rig mobili zation fees, and others, as discussed in section V.D.1 of this p reamble. Many SERs also expressed concerns about staffing limitat ions at closed landfills, who may have limited staff to ove rsee extended GCCS design, operations, maintenance, and complianc e. For***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 161 of 324

landfills that closed after [insert date of publication in the Federal Register] , the EPA understands that gas quality will remain a concern and it has provided an alternative set of GCCS removal criteria based on site-specific emissions, as discussed in section VIII.B of this preamble. Commenters expressed concern about whether landfill s that

have closed and decommissioned their GCCS should be pulled back into control requirements if their emissions fall b etween the current 50 Mg/yr threshold and a more stringent NMO C emission

threshold. These commenters recommended that the EP A exempt these landfills from more stringent control require ments. One commenter added that it would be costly to re-insta ll or refurbish a previously shutdown system and noted th at the system would likely operate for only a few more years befo re the landfill fell below the more stringent NMOC emissio n threshold. For example, the proposed reduction of the NMOC emi ssion rate threshold to 34 Mg/yr NMOC could affect landfills t hat installed a GCCS to comply with the 50 Mg/yr NMOC emissions t hreshold in 40 CFR part 60, subpart WWW (or the state plans or federal plan implementing 40 CFR part 60, subpart Cc), but whose emissions are still above the EPA’s proposed 34 Mg/yr NMOC th reshold. These landfills could have declining gas flows, cou ld be closed, or could have met the 40 CFR part 60, subpart WWW c riteria for capping or removing the GCCS.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 162 of 324 To address concerns about closed landfills, the EPA is proposing to create a subcategory of closed landfil ls, to which an NMOC emission rate threshold of 50 Mg/yr would a pply, instead of an NMOC emission rate of 34 Mg/yr. The subcatego ry of closed landfills is proposed to be defined as a landfill t hat has submitted a closure report as specified in 40 CFR 6 0.38f(f) on or before [ insert date the proposed rule is published in the Federal Register ]. As noted above, the emissions associated with the 65 closed landfills represents less than 7 perc ent of the

total emission reductions achieved from all active and closed landfills expected to control emissions at a level of 34 Mg/yr NMOC in year 2025. The EPA believes today’sthis proposed subcategory for closed landfills alleviates concern s with lowering the threshold for closed landfills, while focusing the proposed changes to the regulatory framework on emi ssion reductions from the existing landfills contributing most significantly to methane emissions from MSW landfil ls. The EPA is requesting input on whether the proposed subcategory for closed landfills is the most approp riate method for controlling emissions and addressing concerns w ith closed landfills, or whether the EPA should consider exemp ting closed landfills from the proposed subpart Cf entirely. Th e EPA is also requesting comments on whether additional provision s should be considered for closed landfills when establishing t he revised***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 163 of 324

Emission Guidelines , including whether the closed landfill subcategory should be expanded to include landfills that closed within 13 months after publication of the Emission Guidelines in the Federal Register

. B. Criteria for Capping or Removing a GCCS Several commenters requested that the EPA reconside r the 15-year criteria for capping or removing a GCCS andone commenter stated that the 15-year period should be longer, rather than shorter. Commenters supported the use o f Tier 4 SEM procedures to help determine the removal or decommi ssioning of existing GCCS. Commenters supported the use of SEM to allow the flexibility to confirm when a closed landfill or cl osed area of a landfill no longer producing gas in significant q uantities can remove or decommission all or a portion of the GCCS . Several of

these commenters referenced a rationale similar to the one they provided for supporting the use of Tier 4 SEM for d etermining

GCCS installation as discussed in section VII.A of this preamble. Several commenters requested that the EPA provide a “step-down” procedure for scaling down GCCS operati ons in nonproducing areas and allowing a GCCS to be removed f rom rule applicability. The EPA is proposing two sets of criteria for cappi ng and removing the GCCS. The first set of criteria is sim ilar to the criteria in subpart Cc, but has been adjusted to re flect the new***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 164 of 324 NMOC emission threshold proposed in this proposal: (1) The landfill is closed, (2) the GCCS has been in operat ion for 15 years, and (3) three successive tests for NMOC emis sions are below the proposed NMOC emission threshold of 34 Mg /yr for open landfills and 50 Mg/yr NMOC for closed landfills. T he EPA is also proposing an alternative set of criteria for c apping or removing the GCCS that employs a SEM demonstration: (1) the landfill, or an area of an active landfill, is clos ed, (2) the GCCS has operated for at least 15 years or the land fill owner/operator can demonstrate that the GCCS will b e unable to operate for 15 years due to declining gas flows, an d (3) the owner or operator demonstrates for 4 consecutive qu arters that there are no surface emissions of 500 ppm or greate r from the

landfill or closed area. The EPA selected a level o f 500 ppm to be consistent with the operational standard for ope rating a GCCS. The operational standard is the surface emiss ions level

that cannot be exceeded once a GCCS has been instal led. The EPA proposes the use of SEM procedures in secti on VI.A of this preamble for determining when to decommissi on wells and for when the landfill can cap or remove a GCCS. If a landfill owner or operator can demonstrate that surface emis sions in the closed area of an open landfill or a closed landfil l are below 500 ppm for 4 consecutive quarters, then they wouldbe able to stop collecting gas from that area or the landfill as a whole.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 165 of 324 After 4 consecutive quarters of no exceedances, the landfill continues to monitor the closed area annually for s urface emission exceedances of 500 ppm or greater. If exce edances are found, the landfill must restart the GCCS in the cl osed area and the GCCS would be required to operate according to proposed 40 CFR part 60, subpart Cf. As discussed in section VII.A of this preamble, sur face emissions monitoring more closely reflects the site ’s actual emissions and accounts for differences in gas gener ation due to waste composition and local conditions. As discusse d in section VII.A of this preamble, sites will have the incenti ve to employ various technologies or practices to minimize surfa ce emissions, thus giving the owner or operator flexibility at bo th the installation and removal stages of LFG collection a nd control. With these rule provisions, the EPA can ensure envi ronmental protection is demonstrated through low surface emis sions and landfill owners and operators will have the flexibi lity to cap or remove the GCCS based on site-specific surface e mission readings. C. Non-producing Areas and Wellhead Standards Commenters have identified the difficulty of operat ing a GCCS in “non-producing” areas and meeting the wellh ead operational standards for the GCCS. They have also contended that the corrective action—expanding the GCCS, is c ounter to a***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 166 of 324 “well-operated” GCCS. Several commenters requested that the EPA provide flexibility to meet the wellhead and other requirements in “non-producing” areas. Commenters generally cons ider a “nonproducing” area as one with declining LFG generatio n and gas flow, which in turn make it difficult to continuous ly meet the operational standards for a GCCS. One commenter sta ted that when landfill gas production decreases significantly, ev en small

amounts of vacuum can draw air into the waste mass causing exceedances of the wellhead oxygen parameter. The c ommenter added that the landfill owner or operator may addre ss the oxygen exceedance by reducing the vacuum to a very low lev el, but then may not be able to maintain negative pressure. Anot her commenter stated that LFG wells in old waste can be very sens itive to vacuum adjustments, easily exceeding the 5 percent oxygen standard not due to excessive air infiltration, but rather due

to low LFG volume. Other commenters noted that the difficulty of meeting the wellhead oxygen/nitrogen operational st andards could

be exacerbated if the EPA were to reduce the NMOC e missions threshold below 50 Mg/yr. As discussed in section VI.B of this preamble, the EPA proposes to remove the requirement to meet wellheadoperating standards for temperature and nitrogen/oxygen. Remo ving these two standards will not only promote earlier and mor e robust

collection of LFG as discussed in section VI.B of t his preamble,***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 167 of 324 but will also give owners and operators flexibility to operate the GCCS in non-producing or closed areas without t he risk of exceeding the oxygen/nitrogen operating standards. Removing the requirement to meet the oxygen/nitrogen operating s tandards and the need for corrective action, including expanding the GCCS, will reduce the burden on both the landfill owner/o perator and the implementing authority. As discussed in section VIII.B of this preamble, the EPA is also providing flexibilit y for temporary decommissioning of wells in closed landfi lls or closed areas of active landfills to provide flexibility fo r meeting negative pressure in areas that can demonstrate lowsurface

emissions. IX. Rationale for the Other Proposed Changes

A. Landfill Gas Treatment The EPA is proposing a definition of treated landfi ll gas and treatment system. A Treatment system would be d efined as a system that filters, de-waters, and compresses land fill gas to levels determined by the landfill owner or operator based on the beneficial end use of the gas. The EPA is proposing this definition to provide compliance flexibility and to promote the beneficial use of LFG. The approach works in conjun ction with the EPA’s proposed expansion of the use of treated landfill gas beyond use as a fuel for a stationary combustion de vice to include other beneficial uses such as vehicle fuel, production***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 168 of 324 of high-Btu gas for pipeline injection, and use as a raw material in a chemical manufacturing process. This definition would be available for all MSW landfill owners/oper ators. The approach is consistent with public comments rec eived on previous landfills documents (67 FR 36475, May 23, 2002; 71 FR 53271, September 8, 2006; 79 FR 41796, July 17, 201 4; 79 FR 41772, July 17, 2014), as well as input from partic ipants in small entity outreach, who stated that the extent o f filtration, de-watering, and compression can be site- and equip mentdependent, and that different sites require differe nt levels of gas treatment to protect the combustion devices tha t use treated LFG as a fuel and ensure good combustion. Commenters on the proposed NSPS (79 FR 41796) and ANPRM (79 FR 41772) supported the expanded use of treated LFG . Commenters including state/local agencies, a large landfill ow ner/operator, and an industry trade association supported the exp anded beneficial use of LFG to include uses beyond subseq uent sale or use and agreed that a broader definition is appropr iate. No commenters opposed the expanded use. Many commenters on the July 17, 2014 proposed NSPS (79 FR 41796) and ANPRM (79 FR 41772) opposed a definition of LFG treatment based on specific numerical values for fi ltration and de-watering. Numerous commenters disagreed with a r equirement to meet specific absolute filtration and dew point sup pression***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 169 of 324 values and contended that a “one-size-fits-all” app roach was not appropriate, and would not reduce emissions. One co mmenter specifically noted the impact that the costs of the se requirements would have on small entities. Commenters estimated costs to comply with the dew p oint reduction. Based on experience, commenters estimate d that chillers alone would cost $500,000 each. Commenters estimated that instrumentation, monitoring, and controls woul d cost an additional $150,000 per chiller, plus up to $60,000 for annual maintenance, monitoring, and operation. These comme nters also expressed concerns about the timeframe for installi ng chillers. Plus, many commenters also expressed concern that t he numerical requirements would be detrimental to existing and p otential beneficial use projects, including potentially shut ting down existing beneficial use projects and preventing fut ure ones. On the other hand, many commenters supported the mo re flexible definition of treatment system that allows the level of treatment to be tailored to the type and design of the specific project equipment. Commenters pointed out that owne rs and operators of combustion equipment are already motiv ated to treat landfill gas to manufacturer specifications to prot ect equipment and maintain warranties. Commenters added that comp liance with a site-specific definition of treatment can be tracke d using a preventative maintenance plan.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 170 of 324 The EPA recognizes that the landfill industry conti nues to develop new LFG beneficial use projects and the EPA continues to support the recovery and use of LFG as an energy so urce. Thus, the EPA is proposing a simplified definition of tre atment as filtering, de-watering, and compressing landfill ga s, but is retaining as alternative a definition of LFG treatm ent based on specific numerical values for filtration and de-wat ering. The simplified definition of treatment, combined wi th siteand equipment-specific monitoring, is expected to p rovide compliance flexibility, ensure environmental protec tion, and promote the beneficial use of LFG. The proposed def inition would allow the level of filtration, dewatering, and comp ression to be tailored to the type and design of the specific equ ipment in which the LFG is used. Owners and operators would n eed to identify monitoring parameters, be able to demonstr ate that such parameters effectively monitor filtration, de-water ing or compression system performance necessary for the en d use of the treated LFG and keep records to demonstrate that th e parameters are being met. Owners/operators would also need to develop a site- specific treatment system monitoring plan that would not onl y accommodate site-specific and end-use specific treatment requir ements for different energy recovery technologies, but would a lso ensure environmental protection. A well-operated system wi th a level of***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 171 of 324 treatment specific to the site and end-use equipmen t would prevent equipment disruptions and limit emissions r esulting during shutdowns or malfunctions. A treatment appro ach that can be tailored to the end use of the gas would also pr omote wider use of LFG energy recovery, by limiting the complia nce burden for those landfills opting to include an energy rec overy component. Landfill gas energy recovery protects th e environment by not only controlling LFG and its components, but also by offsetting conventional sources of energy with a re newable resource for heating, electricity, vehicle fuel, or other

innovative end uses. The EPA also notes that landfi lls complying with a treatment compliance option are also subject to the surface emissions monitoring requirements discussedin section VI.A of this preamble to ensure that the GCCS is we ll operated and surface emissions are minimized. Preparing the monitoring plan would document procedures that landfills are l ikely already following to ensure that the LFG has been adequatel y treated for its intended use and provide verifiable records of proper operation to the EPA or other implementing authorit ies. The plan would be required to include monitoring pa rameters addressing all three elements of treatment (filtrat ion, dewatering, and compression) to ensure the treatment system is operating properly for the intended end use of the treated LFG. The plan would be required to include monitoring me thods,***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 172 of 324 frequencies, and operating ranges for each monitore d operating parameter based on manufacturer’s recommendations o r engineering analysis for the intended end use of the treated LF G. Documentation of the monitoring methods and ranges, along with justification for their use, would need to be inclu ded in the site-specific monitoring plan. In the plan, the own er/operator would also need to identify who is responsible (by job title) for data collection, explain the processes and meth ods used to collect the necessary data, and describe the proced ures and methods that are used for quality assurance, mainte nance, and repair of all continuous monitoring systems. The owner or operator would be required to revise t he monitoring plan to reflect changes in processes, mo nitoring instrumentation, and quality assurance procedures; or to improve procedures for the maintenance and repair of monito ring systems to reduce the frequency of monitoring equipment dow ntime.

Promote the Beneficial Use of LFG. Technical assist ance is available to landfill owners and operators who want to beneficially use LFG. The EPA LMOP is a voluntary a ssistance program that encourages recovery and beneficial use of landfill gas, and in turn, helps to reduce methane emissions from landfills. LMOP has developed many publications andtools to assist stakeholders interested in developing LFG en ergy projects or promote landfill gas energy recovery to various audiences.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 173 of 324 LMOP also provides customized, direct assistance to individual Partners to address their needs, such as preliminar y analyses to estimate landfill gas energy project feasibility or responses to technical questions about particular issues or barr iers involved with project development. LMOP’s Web site has becom e one of the main modes of providing LMOP Partners, others in th e industry, and the public with basic information and keeping t hem abreast of the latest LFG energy–related advances and oppor tunities (http://www.epa.gov/lmop/). Many LMOP resources andtools are available on the Web site including a Project Devel opment Handbook, a preliminary economic assessment model, and a database of LFG energy recovery projects. B. Startup, Shutdown, and Malfunction In its 2008 decision in Sierra Club v. EPA, 551 F.3 d 1019 (D.C. Cir. 2008), the U. S. Court of Appeals for th e District of Columbia Circuit vacated portions of two provisions in the EPA’s CAA section 112 regulations governing the emissions of HAP during periods of SSM. Specifically, the court vaca ted the SSM exemption contained in 40 CFR 63.6(f)(1) and 40 CFR63.6(h)(1), holding that under section 302(k) of the CAA, emiss ions

standards or limitations must be continuous in natu re and that the SSM exemption violates the CAA’s requirement th at some section 112 standards apply continuously.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 174 of 324 Periods of Startup or Shutdown. Consistent with Sie rra Club v. EPA, the EPA is proposing standards in 40 CFR pa rt 60, subpart Cf that apply at all times. In proposing th e standards in this rule, the EPA has taken into account startu p and shutdown periods and, for the reasons explained bel ow, has not proposed alternate standards for those periods. The part 60 general provisions, which define startu p, shutdown, and malfunction, were written for typical industrial or manufacturing sources and associated processes. Many of these sources and processes may, at times, be shut down e ntirely for clean-out, maintenance, or repairs, and then restar ted. Applying the standards at all times, including periods of st artup and shutdown, is intended to minimize excess emissions when the source or process ceases operation or commences ope ration, or during malfunctions. Landfill emissions, however, a re produced by a continuous biological process that cannot be s topped or restarted. For landfills, the primary SSM concern i s with

malfunction of the landfill GCCS and associated mon itoring equipment, not with the startup or shutdown of the entire source. Thus, SSM provisions in the 40 CFR part 60, subpart Cf focus primarily on malfunction of the gas collectio n system, gas control system, and gas treatment system, which is part of the gas control system.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 175 of 324 Periods of Malfunction. Periods of startup, normal operations, and shutdown are all predictable and ro utine aspects of a source’s operations. Malfunctions, in contrast , are neither predictable nor routine. Instead they are, by defin ition sudden, infrequent and not reasonably preventable failures of emissions control, process or monitoring equipment. (40 CFR 6 0.2). The EPA interprets CAA section 111 as not requiring emissio ns that occur during periods of malfunction to be factored into d evelopment of CAA section 111 standards. Nothing in CAA section 1 11 or in case law requires that the EPA consider malfunctions whe n determining what standards of performance reflect the degree of emission limitation achievable through “the application of t he best system of emission reduction” that the EPA determin es is adequately demonstrated. While the EPA accounts for variability in setting emissions standards, nothing in CAA sect ion 111 requires the agency to consider malfunctions as par t of that analysis. A malfunction should not be treated in th e same manner as the type of variation in performance that occurs during routine operations of a source. A malfunction is a failure of the source to perform in a “normal or usual manner” and no statutory language compels EPA to consider such eve nts in setting CAA section 111 standards of performance. Further, accounting for malfunctions in setting emi ssion standards would be difficult, if not impossible, gi ven the***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 176 of 324 myriad different types of malfunctions that can occ ur across all sources in the category and given the difficulties associated with predicting or accounting for the frequency, de gree, and duration of various malfunctions that might occur. As such, the performance of units that are malfunctioning is not “reasonably” foreseeable. See, e.g., Sierra Club v. EPA, 167 F.3 d 658, 662 (D.C. Cir. 1999) (“The EPA typically has wide latit ude in determining the extent of data-gathering necessary to solve a problem. We generally defer to an agency’s decision to proceed on the basis of imperfect scientific information, r ather than to ‘invest the resources to conduct the perfect study. ’”) See also, Weyerhaeuser v. Costle, 590 F.2d 1011, 1058 (D.C. C ir. 1978) (“In the nature of things, no general limit, indivi dual permit, or even any upset provision can anticipate all upse t situations. After a certain point, the transgression of regulat ory limits caused by ‘uncontrollable acts of third parties,’ s uch as strikes, sabotage, operator intoxication or insanit y, and a variety of other eventualities, must be a matter fo r the administrative exercise of case-by-case enforcement discretion, not for specification in advance by regulation.”). In addition, emissions during a malfunction event can be signifi cantly higher than emissions at any other time of source operatio n. For example, if an air pollution control device with 99 percent removal goes off-line as a result of a malfunction (as might***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 177 of 324 happen if, for example, the bags in a baghouse catc h fire) and the emission unit is a steady state type unit that would take days to shut down, the source would go from 99 perc ent control to zero control until the control device was repair ed. The source’s emissions during the malfunction would be 100 times higher than during normal operations. As such, the emissions over a 4-day malfunction period would exceed the an nual emissions of the source during normal operations. A s this example illustrates, accounting for malfunctions co uld lead to standards that are not reflective of (and significa ntly less stringent than) levels that are achieved by a well- performing non-malfunctioning source. It is reasonable to inte rpret section 111 to avoid such a result. The EPA’s approach to m alfunctions

is consistent with section 111 and is a reasonable interpretation of the statute. In the event that a source fails to comply with the applicable CAA section 111 standards as a result of a malfunction event, the EPA would determine an appro priate response based on, among other things, the good fai th efforts of the source to minimize emissions during malfunction periods, including preventative and corrective actions, as w ell as root cause analyses to ascertain and rectify excess emis sions. The

EPA would also consider whether the source’s failur e to comply with the CAA section 111 standard was, in fact, sud den,***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 178 of 324 infrequent, not reasonably preventable and was not instead caused in part by poor maintenance or careless oper ation (40 CFR § 60.2 (definition of malfunction)). If the EPA determines in a particular case that an enforcement action against a source for violation o f an emission standard is warranted, the source can raise any andall defenses

in that enforcement action and the federal district court will determine what, if any, relief is appropriate. The same is true for citizen enforcement actions. Similarly, the pre siding officer in an administrative proceeding can conside r any defense raised and determine whether administrative penalti es are appropriate. In summary, the EPA interpretation of the CAA and, in particular, CAA section 111 is reasonable and encou rages practices that will avoid malfunctions. Administrat ive and judicial procedures for addressing exceedances of t he standards fully recognize that violations may occur despite g ood faith efforts to comply and can accommodate those situati ons. In several prior rules, the EPA had included an aff irmative defense to civil penalties for violations caused by malfunctions in an effort to create a system that incorporates s ome flexibility, recognizing that there is a tension, i nherent in many types of air regulation, to ensure adequate co mpliance while simultaneously recognizing that despite the m ost diligent***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 179 of 324 of efforts, emission standards may be violated unde r circumstances entirely beyond the control of the so urce. Although the EPA recognized that its case-by-case e nforcement discretion provides sufficient flexibility in these circumstances, it included the affirmative defense to provide a more formalized approach and more regulatory clarit y. See Weyerhaeuser Co. v. Costle, 590 F.2d 1011, 1057-58 (D.C. Cir. 1978) (holding that an informal case-by-case enforc ement discretion approach is adequate); but see Marathon Oil Co. v. EPA, 564 F.2d 1253, 1272-73 (9th Cir. 1977) (requir ing a more formalized approach to consideration of “upsets bey ond the control of the permit holder”). Under the EPA’s reg ulatory affirmative defense provisions, if a source could d emonstrate in a judicial or administrative proceeding that it hadmet the requirements of the affirmative defense in the regu lation, civil penalties would not be assessed. Recently, the U. S . Court of Appeals for the District of Columbia Circuit vacate d an

affirmative defense in one of the EPA’s CAA section 112 regulations. NRDC v. EPA, 749 F.3d 1055 (D.C. Cir., 2014) (vacating affirmative defense provisions in the CAA section 112 rule establishing emission standards for Portland c ement kilns). The court found that the EPA lacked authority to es tablish an affirmative defense for private civil suits and hel d that under the CAA, the authority to determine civil penalty a mounts in***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 180 of 324 such cases lies exclusively with the courts, not th e EPA. Specifically, the court found: “As the language of the statute makes clear, the courts determine, on a case-by-cas e basis, whether civil penalties are ‘appropriate.’” See NRD C at 1063 (“[U]nder this statute, deciding whether penalties are ‘appropriate’ in a given private civil suit is a jo b for the courts, not EPA.”). In light of NRDC , the EPA is not including a regulatory affirmative defense provision in this ru lemaking. As explained above, if a source is unable to comply wi th emissions standards as a result of a malfunction, the EPA may use its case-by-case enforcement discretion to provide flex ibility, as appropriate. Further, as the U.S. Court of Appeals for the District of Columbia Circuit recognized, in an EPA or citizen enforcement action, the court has the discretion to consider any defense raised and determine whether penalties are appropriate. Cf. NRDC, at 1064 (arguments that violation were ca used by unavoidable technology failure can be made to the c ourts in future civil cases when the issue arises). The same is true for the presiding officer in EPA administrative enforce ment actions. 67

67 Although the NRDC case does not address the EPA’s authority to establ ish an affirmative defense to penalties that is available in administrative enforcement actions, EPA is not including such an a ffirmative defense in the proposed rule. As explained above, such an affirmat ive defense is not necessary. Moreover, assessment of penalties for vi olations caused by malfunctions in administrative proceedings and judi cial proceedings should be***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 181 of 324 Limit on SSM duration. Subpart WWW of 40 CFR part 6 0 limits

the duration of SSM events for MSW landfills to 5 d ays for the landfill gas collection system and 1 hour for treat ment or control devices. Proposed 40 CFR part 60, subpart C f does not include the 5-day and 1-hour time limitations becau se some malfunctions cannot be corrected within these timef rames. Excluding these provisions is consistent with Sierr a Club v. EPA (551 F.3d 1019 (DC Cir. 2008)), which concluded tha t that emission standards apply at all times, including pe riods of SSM, and 40 CFR 60.11(d), which states that at all times , including periods of startup, shutdown and malfunction, owner s or operators shall, to the extent practicable, maintai n and operate any affected facility including associated air poll ution control equipment in a manner consistent with good air poll ution control practice for minimizing emissions. The proposed rev isions clarify that the NSPS standards continue to apply d uring periods

of SSM. To prevent free venting of landfill gas to the atmo sphere during control device malfunctions, we propose to i nclude a requirement in subpart Cf (40 CFR 60.34f(e)) that s tates that in the event the collection or control system is not o perating, the gas mover system must be shut down and all valves i n the

consistent. Cf. CAA section 113(e) (requiring both the Administrator and the court to take specified criteria into account when assessing penalties).***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 182 of 324 collection and control system contributing to venti ng of gas to the atmosphere must be closed within 1 hour. The EP A proposes to use the term “not operating,” which includes period s when the gas collection or control system is not operating f or whatever reason, including when the gas collection or contro l system is inoperable. The EPA requests comment on the technical feasibility of this approach as well as alternate w ays to prevent free venting of landfill gas to the atmosph ere during

control device malfunctions. Shutting down the gas mover equipment and all valve s contributing to venting of gas to the atmosphere mi nimizes emissions from the landfill while the control syste m is not operating and is being repaired. Compliance with pr oposed 40 CFR 60.34f(e) does not constitute compliance with the a pplicable standards in proposed 40 CFR 60.36f ; however, as a practical matter it is unlikely that there would be a violati on since no gas would be flowing to the control device . Compliance with proposed 40 CFR 60.34f(e) is necessary to demonstra te compliance with the general duty to minimize emissions in 40 C FR 60.11(d) during control or collection system malfunctions. Under proposed 40 CFR part 60, subpart Cf, landfill owners/operators must keep records of combustion te mperature, bypass flow, and periods when the flare flame or th e flare pilot flame is out. However, without additional provision s, the EPA Commented [A12]: New text added***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 183 of 324 would have no way to gauge the severity of an emiss ions exceedance that may occur when these operating para meters are not being met or when the control device is not ope rating. Therefore, the EPA is proposing to include provisio ns for landfill owners/operators to estimate NMOC emission s when the control device or collection system is not operatin g. The landfill owners/operators may use whatever informat ion is available to estimate NMOC emissions during the per iod, including but not limited to, landfill gas flow to or bypass of the control device, the concentration of NMOC (from the most recent performance test or from AP-42), and the amo unt of time the control device is not operating. Landfill owner s/operators would keep records of the estimated emissions and w ould report the information in the annual compliance report. As discussed above, malfunctions are by definition sudden, infrequent and not reasonably preventable failures of emissions control, process or monitoring equipment. Further, there are myriad different types of malfunctions that can occ ur and there are significant difficulties associated with predic ting or accounting for the frequency, degree, and duration of various malfunctions that might occur. As a result, the EPA believes that it is generally not technically feasible to es tablish an alternative emission standard that would apply duri ng periods of

malfunction. The EPA also believes that it would be difficult to***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 184 of 324

defend an alternative standard that does not achiev e a level of emission reduction comparable to that required by t he standard that applies during periods of normal operation in circumstances where there are steps that an owner or operator cou ld take to achieve such reductions such as shutting down the p rocess or having a second control device. In the immediate ca se, by shutting down the flow to the flare or other contro l device a source is unlikely to be in violation of the 98 per cent emission reduction requirement since there will be no gas fl owing to the control device. We are, however, interested in comm ent on whether there are alternative ways in which the emi ssion limit could be complied with when the control device malf unctions. C. Definitions and Other Rule Changes. We propose to include definitions of “household was te” and “segregated yard waste” in proposed 40 CFR part 60, subpart Cf to clarify our intent regarding the applicability o f proposed subpart Cf to landfills that do not accept househol d waste, but accept segregated yard waste. We also proposed to e xclude

construction and demolition waste from the definiti on of household waste. We intend for subpart Cf to apply to municipal solid waste landfills that accept general householdwaste (including garbage, trash, sanitary waste), as indi cated in the

definitions. We do not intend the landfills rules t o apply to landfills that accept only segregated yard waste or a***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 185 of 324 combination of segregated yard waste and non-househ old waste

such as construction and demolition waste. X. Request for Comment on Specific Provisions A. Defining Closed Areas of Open Landfills. In the ANPRM for the Emission Guidelines (79 FR 417 72), the EPA requested input on how non-producing areas of t he landfill, i.e., areas that are no longer generating landfill gas, could be excluded from gas collection requirements when desi gning a GCCS (79 FR 41792). The EPA also sought input on whether the current criteria for capping or removing a GCCS are appropr iate, one of which requires that the landfill be closed (79 FR 4 1783). As discussed in section VIII.B of this preamble, we ar e proposing a second set of alternative criteria for capping or r emoving the

GCCS at closed landfills or closed areas of active landfills, based on surface emissions monitoring. Commenters expressed concern with the requirement f or closed areas to be physically separated in order to be excluded from GCCS requirements, noting that many closed are as of active landfills are non-producing but remain physically c onnected to

other areas of the landfill. To help address the difficulty of controlling landf ill gas in low-producing areas, the EPA is proposing an alt ernative set of criteria for capping or removing the GCCS that e mploys a SEM demonstration: 1) the landfill is closed or an area of an active***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 186 of 324 landfill is closed, 2) the GCCS has operated for at least 15 years or the landfill owner/operator can demonstrat e that the GCCS will be unable to operate for 15 years due to declining gas flows, and 3) the landfill or closed area demonstra tes for 4 consecutive quarters that there are no surface emis sions of 500 ppm or greater. The EPA is also requesting comment on whether owners or operators of physically separated, closedareas of landfills may model NMOC emission rates, or may det ermine the flow rate of landfill gas using actual measurements , to determine NMOC emissions in order to identify areas that can be excluded from gas collection. The EPA considers are as to be physically separated if they have separate liners a nd gas cannot migrate between the separate areas. To further address non-producing areas, proposed 40 CFR part 60, subpart Cf contains procedures for excludi ng areas from gas collection and control. Owners or operators of landfills with physically separated, closed areas may demonst rate that the quantity of NMOC emissions from the area is less th an 1 percent

of the total NMOC emissions from the entire landfil l, and thus exclude the area from control. Under proposed 40 CF R part 60, subpart Cf, owners or operators of landfills with p hysically separated, closed areas may model NMOC emission rat es, or may determine the flow rate of landfill gas using actua l measurements, to determine NMOC emissions. Using ac tual flow***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 187 of 324 measurements would yield a more precise measurement of NMOC emissions for purposes of demonstrating the closed area represents less than 1 percent of the landfills tot al NMOC

emissions. Because both of these topics rely on defining a clo sed area of a landfill, the EPA requests comment on how to d efine closed areas of open landfills. B. Enhanced Surface Emissions Monitoring The proposed 40 CFR part 60, subpart Cf collection and control requirements are intended to ensure that la ndfills maintain a tight cover that minimizes any emissions of landfill gas through the surface. The surface emissions moni toring procedures in proposed 40 CFR part 60, subpart Cf a re consistent with 40 CFR part 60, subpart WWW and require quarte rly surface emissions monitoring to demonstrate that the cover and gas collection system are working properly. However, we are also considering and requesting additional public input on a potential alternative approach to surface emissions monitoring. The alternative surface monitoring approach include s changing the walking pattern that traverses the lan dfill from 30 meters (98 ft) to 25 ft and adding a methane concen tration limit of 25 ppm as determined by integrated surface emiss ions monitoring. This would be in addition to the 500 pp m emission concentration as determined by instantaneous surfac e emissions***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 188 of 324 monitoring. Integrated surface emissions monitoring provides an average surface emission concentration across a spe cified area. For integrated surface emissions monitoring, the sp ecified area would be individually identified 50,000 square ft g rids. A tighter walking pattern and the addition of an inte grated methane concentration limit would more thoroughly e nsure that the collection system is being operated properly, t hat the landfill cover and cover material are adequate, andthat methane

emissions from the landfill surface are minimized i n all types of climates. As part of these potential changes, th e EPA is also considering not allowing surface monitoring when th e average wind speed exceeds 5 miles per hour (mph) or the in stantaneous wind speed exceeds 10 mph because air movement can affect whether the monitor is accurately reading the metha ne concentration during surface monitoring. We are con sidering this change because conducting surface emissions monitor ing during windy periods may not yield readings that are repre sentative of the emissions. The EPA requested public comment on this same enhanced approach in the landfills NSPS (79 FR 4182 2) and ANPRM (79 FR 41789). Many commenters supported the enhanced surface moni toring provisions for detecting surface emissions. A state agency supported reducing the traverse pattern to 25 feet, stating that the tighter traverse pattern would increase the cha nce of***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 189 of 324 detecting exceedances. An environmental organizatio n supported all elements of the enhanced surface monitoring andcontended that the current monitoring at 30 meter intervals l eaves most areas of the landfill unmonitored. Both these comme nters suggested that the walking pattern be varied each q uarter (i.e., offset by 10 meters) to monitor additional areas ov er time. The environmental organization supported an integrated reading because it would be a better indicator of GCCS perf ormance and they contended that the additional costs were not u nreasonable. Many commenters opposed the enhanced surface monito ring provisions. Commenters that opposed the enhanced su rface monitoring provisions primarily cited the additiona l costs and contended that the additional expense was not warra nted because

of limited environmental benefits. Two commenters c ommissioned a study to compare the level of effort and monitoring results of the CA LMR to the SEM requirements under the curren t NSPS (40 CFR part 60, subpart WWW). The CA LMR utilizes a 25 ft traverse pattern, an instantaneous as well as integrated rea ding, and prevents sampling during windy conditions (greater than 5 mph average and greater than 10 mph instantaneous). The study examined monitoring results for eight qua rters of NSPS surface monitoring at 42 California landfills, encompassing 27,140 acres. Those results were compared to CA LMRsurface monitoring for 10 quarters at 72 California landfil ls, including***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 190 of 324 the 42 landfills conducting NSPS surface monitoring , encompassing a total of 57,151 acres. Among other o bservations, the study concludes that although the CA LMR surfac e emission monitoring requirements detected 2.1 percent more e xceedances than NSPS surface emission monitoring requirements, detecting

these additional exceedances is not cost effective. The study also concluded that under the NSPS monitoring, only one landfill was required to expand its GCCS, while under the CA LMR monitoring, only three landfills were required to e xpand the

GCCS. The two commenters that commissioned the stud y contended

that the additional cost to conduct enhanced surfac e monitoring, estimated by the EPA to be seven times more expensi ve than NSPS monitoring, was an extraordinary amount of money to spend detecting exceedances at merely an additional 2.8 p ercent of acres monitored, while increasing gas collection at only one

landfill. The EPA examined the data supporting the study as p rovided by one of the commenters. The data allowed for dire ct comparison of exceedance data from 29 landfills, although for different time periods. The study and supporting data provide evidence of greater exceedances under the California approach t han the current approach. However, the EPA was unable to de termine the magnitude of emission reductions that might result from the greater exceedances under the California approach. See the***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 191 of 324 docketed memorandum entitled “Analysis of Surface E xceedances

from California Landfills under the New Source Perf ormance Standards and the California Landfill Methane Rule. ” Many commenters, including many state agencies, opp osed limiting surface monitoring during windy conditions , stating that the wind restrictions would be a significant i nhibitor to completing the required monitoring in many regions of the country due to typical windy conditions. Commenters also stated

that it would be difficult to schedule and reschedu le dedicated sampling crews and conditions could change quickly during sampling events, causing crews to stop monitoring. For proposed 40 CFR part 60, subpart Cf, the EPA es timated the costs associated with both the proposed subpart Cf surface monitoring requirements (which are the same as the surface monitoring requirements in 40 CFR part 60, subpart WWW) and potential changes to the surface monitoring provisi ons under the proposed 2.5/34 option and the proposed 2.5/40 opti on and applied them to the set of existing landfills that would be subject to control requirements under the respectiv e option. To determine the costs, the EPA used the following ass umptions:

most landfills will hire a contractor to conduct th e quarterly monitoring. The landfill will incur labor costs bas ed on the time it takes to walk the traverse (hours per acre) , the size of the landfill (acres), and a labor rate (dollars per hour). The***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 192 of 324 landfill will also incur an equipment rental rate ( dollars per hour) as well as a flat fee for purchasing calibrat ion gases and hydrogen to fuel the equipment. Equipment rental ra tes are dollar per day/week/month, depending on the size of the landfill and time to traverse the acreage during each quarte rly period. See the docketed memo, “Updated Methodology for Est imating Testing and Monitoring Costs for the MSW Landfill R egulations. 2015,” which contains the details for determining t he costs that

a landfill would incur to conduct enhanced surface monitoring. Using the techniques discussed in section V.B of th is preamble, the EPA estimated the number of landfills that are expected to install controls under the baseline, as well as the proposed option 2.5/34 and option 2.5/40. Then, the EPA applied surface monitoring costs to the respective set of l andfills

because landfills that must install controls must a lso conduct surface monitoring. Table 4 of this preamble compar es the enhanced surface monitoring costs that would be inc urred for new landfills under the baseline and proposed option 2. 5/34 and proposed option 2.5/40.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 193 of 324 Table 4. Comparison of Baseline Surface Monitoring Versus Enhanced Surface Monitoring in 2025

Control option Surface

monitoring type Number of

landfills controllin g Annual

Cost Incrementa

l Cost Total Cost

per controlled landfill Incremental

cost per controlled landfill Baselin e 2.5/50 (2.5 million Mg design capacit y/50 Mg/yr NMOC) No change (30

meter traverse)

574 6,327,000 NA 11,000 NA

Enhanced (25- foot traverse, integrated sample) 43,831,000 37,504,000 76,400 65,300

Option 2.5/40 (2.5 million Mg design capacit y/40 Mg/yr NMOC) No change (30

meter traverse)

636 6,741,000 414,000 10,600 700

Enhanced (25- foot traverse, integrated sample) 46,746,000 40,419,000 73,500 63,600

Propose d Option 2.5/34 (2.5 million Mg design capacit y/34 Mg/yr NMOC) No change (30

meter traverse)

680 7,062,000 735,000 10,400 1,100

Enhanced (25- foot traverse, integrated sample) 49,037,000 42,710,000 72,100 62,800

Several factors contribute to the cost of enhanced surface monitoring. Monitoring along a traverse with a 25 f t. interval would increase monitoring time, and thus the labor costs, compared to monitoring along a 30 meter (98 ft.) in terval. Monitoring along the tighter traverse pattern wouldtake approximately 4 times as long, because the distance is***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 194 of 324 approximately 4 times greater. For a landfill to co nduct the integrated surface emissions monitoring, the EPA as sumed the landfill would rent a handheld portable vapor analy zer with a data logger. The data logger is necessary to obtain an integrated reading over a single 50,000 square foot grid. However, the EPA does not expect that requiring an integrated methane concentration would add significant cost be cause landfills could use the same instrument that they c urrently use for the instantaneous readings and these instrument s can be programmed to provide an integrated value as well a s an instantaneous value. The EPA recognizes that these provisions could redu ce surface emissions and that these emissions reductio ns are difficult to quantify. The EPA also understands tha t there are potential implementation concerns with these enhanc ed procedures. Surface monitoring is a labor intensive process and tightening the grid pattern would increase costs. O f the 574 landfills expected to be controlling in 2025 under the baseline, it would take these landfills over 42 hours, on ave rage, to complete each quarterly traverse pattern. Tightenin g the traverse pattern to 25 ft instead of 30 meters woul d require over 165 hours per quarter, or nearly 500 additiona l hours per year, per landfill, compared to the current 30-mete r traverse pattern.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 195 of 324 At this time, the EPA is not proposing surface moni toring provisions that differ from those outlined in 40 CF R part 60, subpart WWW, but we are soliciting comment on the v arious elements of enhanced surface emissions monitoring ( the width of the traverse pattern, offsetting the walking patter n each quarter (i.e., offset by 10 meters), an integrated reading of 25 ppm, and restrictions during windy conditions), as well as techniques and data to estimate the emission reduct ions associated with enhanced surface monitoring.

C. Wet Landfills In the ANPRM (79 FR 41784), we solicited input on s eparate

thresholds for wet landfills and how wet landfills might be defined. Among other concerns, we received feedback from commenters expressing concern on potential overlap between wet

landfills handled under the Emission Guidelines andbioreactor landfills handled under 40 CFR part 63, subpart AAAA (National

Emission Standards for Hazardous Air Pollutants: Mu nicipal Solid Waste Landfills). A landfill is defined as a biorea ctor under 40 CFR part 63, subpart AAAA if it has added liquids o ther than

leachate into the waste mass in a controlled fashio n 68 ; such

68 Under 40 CFR part 63, subpart AAAA, bioreactor mea ns a MSW landfill or portion of a MSW landfill where any liquid other th an leachate (leachate includes landfill gas condensate) is added in a con trolled fashion into the waste mass (often in combination with recirculating leachate) to reach a minimum average moisture content of at least 40 per cent by weight to accelerate or enhance the anaerobic (without oxygen ) biodegradation of the waste.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 196 of 324 bioreactor landfills are required to install and op erate a GCCS on an accelerated schedule compared to non-bioreact or landfills. Once a landfill is required to install and operate a GCCS under either 40 CFR part 63, subpart AAAA, or 40 CFR part 60, subparts WWW and Cc, the GCCS requirements are the same. In addition to bioreactors as defined under 40 CFR part 63, subpar t AAAA, the EPA is aware of 31 bioreactor projects permitted un der the research, development, and demonstration (RD&D) rul e in 11 states and one project on tribal lands 69 . These bioreactor landfills generally do not meet the 40 percent by w eight moisture component of the bioreactor definition in 40 CFR part 63, subpart AAAA. Based on the options analyzed andpresented in Table 3 of this preamble, proposed option 2.5/34 is estimated to

achieve reductions of NMOC and methane emissions at 651 existing open landfills in year 2025. Of these 651 landfills , 18 are identified as having RD&D permits, which permit liq uids addition; 343 are located in areas receiving greate r than 40 inches of precipitation each year; and an additiona l 16 landfills report leachate recirculation activities and a k value of 0.057 year -1 or greater to subpart HH of the GHGRP, but are not located in areas receiving 40 inches of precipi tation or

69 EPA/600/R-14/335. Permitting of Landfill Bioreacto r Operations: Ten Years after the RD&D Rule.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 197 of 324 more, for a total of 377 “wet” landfills out of tho se required

to control emissions. Collectively, reductions from these 377 wet landfil ls constitute approximately 50 percent of the incremen tal reductions achieved by the proposed option 2.5/34. Nearly all of these incremental reductions are coming from the 34 3 landfills that are located in areas receiving 40 inches of pr ecipitation or more. Based on this analysis, the NMOC thresholdof 34 Mg/yr in this proposal achieves significant reduction in emissions

from wet landfills. The EPA conducted a preliminary analysis to determi ne the

additional reductions that could be achieved if the initial lag time was shortened by 1 year and the expansion lag time was shortened by 2 years and applied to open wet landfi lls in

addition to the lower NMOC emission threshold of 34 Mg/yr. The results of this analysis show that an additional ap proximately 220 Mg/yr of reductions in NMOC emissions and 35,20 0 Mg/yr of reductions in methane (879,000 mtCO 2 e/yr) could be achieved from

these 377 wet landfills in 2025. It is important to note that the impacts of the opt ions in Table 3 as well as this preliminary analysis of wet landfills were conducted using a k value of 0.04 for any land fill that is

located in an area with at least 25 inches of rainf all, consistent with the analysis discussed at 79 FR 418 05. This***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 198 of 324 modeling parameter was used for all but nine of the 377 wet landfills discussed above. Those nine landfills, wh ich are either RD&D landfills or reported significant leach ate recirculation to subpart HH of the GHGRP were model ed using a k value of 0.02 because they were located in arid are as. The results of the impacts analyses presented in Ta ble 3 of this preamble and above could differ significantly if alternative modeling parameters (k and/or L o ) were used to model emissions from this group of wet landfills. For exa mple, subpart

HH of the GHGRP uses a k value of 0.057 for landfil ls that exceed 40 inches per year when considering both lea chate recirculation and precipitation. The EPA also ident ified a study containing alternative k values for five different bioreactor

landfills 70 . One commenter urged the EPA to consider more representative k values when calculating emission r eductions from wet landfills, and cited several studies for E PA review 71,72,73 . This commenter also requested that the EPA adopt

70 Barlaz, Morton et al., Performance of North Americ an Bioreactor Landfills II: Chemical and Biological Characteristics. Journa l of Environmental Engineering. Volume 136, No. 8. August 2010. 71 Xiaoming Wang et al., Using Observed Data to Improve Estimated Methane Collection From Select U.S. Landfills, Environ. Sci. Technol. 3251, 3256 (2013). 72 Hamid R. Amini et al., Comparison of First-Order Decay Modeled and Actual Field Measured Municipal Solid Waste Landfill Metha ne Data, 33 Waste Management 2720, 2725 (2013). 73 Barlaz et al ., Controls on Landfill Gas Collection Efficiency: Instantaneous and Lifetime Performance 59 J. Air & Waste Mgmt. Ass’n 1399, 1402-03 (Dec. 2009)***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 199 of 324 shorter lag times for these wet landfills. Another commenter urged the EPA to finalize the changes proposed in 2 009 to AP-42 emission factors for MSW landfills, which included a much higher k value of 0.3 for wet landfills, among other chang es 74 . Another commenter provided input that leachate recirculatio n will have negligible impact on the total precipitation value that ultimately dictates which k value to use. This comm enter also referenced its prior comments expressing concerns t hat the draft AP-42 k value for wet landfills was too high, and p rovided several studies containing alternative k values for wet

landfills 75,76,77

. Given the additional emission reductions that couldbe achieved from shortening the lag times at wet landf ills and in consideration of the President’s Methane Strategy, the EPA is soliciting input on whether the wet landfills not s ubject to the requirements in 40 CFR part 63, subpart AAAA shouldbe subject to different schedules for installing and expanding their GCCS

74 U.S. EPA AP 42, Fifth Edition, Volume I, Chapter 2 , Draft Section 2.4: Solid Waste Disposal http://www.epa.gov/ttn/chief/ap42/ch02/draft/d02s04 .pdf 75 Staley, B.F. and M.A. Barlaz, 2009, "Composition of Municipal Solid Waste in the U.S. and Implications for Carbon Sequestrati on and Methane Yield," Journal of Environmental Engineering, Vol. 135, No. 10, October 1, 2009. 76 U.S. EPA, Landfill Bioreactor Performance, Second Interim Re port; EPN600/R-07/060, Office of Research and Development , National Risk Management Laboratory: Cincinnati, OH, 2006. 77 Tolaymat, T.M., Green, R.B., Hater, G.R., Barlaz, M .A., Black, P., Bronston, D., and J. Powell, "Evaluation of Landfil l Gas Decay Constant for Municipal Solid Waste Landfills Operated as Bioreac tors." Submitted to the Journal of the Air & Waste Management Association. 2009.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 200 of 324 under the Emission Guidelines. Additionally, the EP A requests

comment on how these wet landfills that are not bio reactors (as defined in subpart AAAA) might be defined. Finally, recognizing the wide range of k values used to model emissions at wet landfills (0.057 to 0.3), the EPA requests comment and data to support revising the k value used for assessing the impacts on wet landfills, as well as the k value landfills sho uld use in

Tier 1 and Tier 2 emission threshold determinations . The EPA also requests comment on whether revisions to the k value for wet landfills would require changes to the Lo model ing parameter

for wet landfills. D. Monitoring Wellhead Flowrate

Based on comments received and discussed in section VI.B of this preamble, as well as the proposal to eliminate the operating standards for oxygen/nitrogen and tempera ture, the EPA is requesting input on whether it should add a requ irement to monitor wellhead flowrate to help ensure a well-ope rated GCCS. Monitoring wellhead flow rate would allow the landf ill owner or operator to detect low gas flow and whether a well is waterlogged, clogged, or pinched. The EPA is also requesting comment on any other wellhead monitoring parameters that would help ensure a well-operated GCCS. E. Third Party Design Plan Certification Program***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 201 of 324 In the ANPRM for existing landfills (79 FR 41784, J uly 17, 2014), the EPA solicited input on the possibility o f establishing a third-party design plan certificatio n program and provided examples of several rules and programs wit h third-party verification components. The third-party program wo uld supplement or replace the current approach of requi ring EPA or state review and approval of site-specific design p lans and plan revisions with a program whereby independent third parties would review the design plans, determine whether they con form to applicable regulatory criteria, and report their fi ndings to the approved state programs or the EPA (for states with out approved programs). The process of approving site-specific d esign plans and plan revisions can be extremely resource-intens ive for regulators and regulated entities alike. The EPA be lieves modifying the regulations to provide for the reviewand approval of the plans by competent and independent third-par ties could reduce these burdens. Such an independent program w ould need to be designed to ensure that, among other things, the third parties are competent, accurate, independent, and a ppropriately accredited. The program would also need to ensure t hat the reviews are thorough, independent, and conducted pu rsuant to clear and objective design plan review criteria. Fi nally, the program would need to ensure that the system is tra nsparent, including requiring appropriate public disclosures, and that***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 202 of 324 there is regular and effective oversight of the thi rd-party system. Some criteria for auditor competence, indep endence, reporting, and oversight requirements provisions mi ght include the following:

• Engaging a third-party inspection team (team) and submitting the members’ resumes and qualifications to EPA;

• Requiring the team to have at least one person with landfill industry expertise acceptable to the EPA, one expert in environmental compliance auditing, and on e expert in chemical process safety management;

• Restricting team members to those who have not prev iously performed work for the respondents;

• Restricting team members from working for the respo ndents or any of the respondents’ officers for 5 years aft er completion of inspections ;

• After giving the respondents notice of the first up coming inspection, restricting the team from communicating with its respondents unless EPA is copied on the communi cation (communications during on-site inspections are exce pted);

• Unannounced follow-up inspections with no notice to respondents but advance notice to the EPA;

• Restricting respondents from having control over th e timing of any of the follow-up inspections;

• Having the EPA or the delegated authority retain th e right to accompany the team on any inspection;

• Within 15 days of each inspection, requiring the te am to simultaneously submit to the EPA and the respondent s an inspection report, photographs, and digital video o f the inspection;

• Denying the opportunity to review any draft or fina l inspection report before its submittal.

The EPA developed the above provisions based on the theoretical and empirical research for best practic es for independent third party audits.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 203 of 324 Commenters on the ANPRM generally did not support a third party design plan certification program and cited s everal reasons. Commenters noted that the ANPRM (79 FR 417 72) discussion of the program was overly general and th at the EPA did not adequately describe the possible design fea tures. One commenter expressed concerns that the examples of t hird-party certification presented in the ANPRM are neither co mparable nor relevant to the review of MSW landfill GCCS design plans. One commenter acknowledged that a third-party reviewer system could reduce the burden and backlog experienced by review ing agencies, but expressed concern that the costs of verificatio n would be significant. Another commenter indicated the EPA di d not present any economic and implementation impacts concerning such a program in the ANPRM and requested that EPA provide more details. Commenters also expressed concern about fi nding

consultants that would be free of conflicts of inte rest given

the consolidated nature of the MSW landfill industr y. One commenter noted that cost and potential conflicts o f interest were cited as reasons that the EPA did not adopt a third-party certification program for the GHGRP. Another commen ter agreed that there was the potential for conflicts of inter est and stated that design plan review is an essential gove rnment oversight and should not be delegated. Commenters a lso urged the EPA to thoroughly review the many issues that couldarise with a***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 204 of 324 third-party certification program and urged the EPA to take further notice and comment before promulgating such a program. Several commenters on the ANPRM (79 FR 41772) solic ited additional details on components of a proposed thir d-party certification program, and the EPA is providing fur ther details in this proposal. In this notice, the EPA is also s eeking additional input on the possibility of establishing a thirdparty design certification program. This preamble d iscussion provides notice of the key features the EPA is cons idering in such a program to ensure the integrity of such a pr ogram, including the use of effective auditors and audits. See [DOCUMENT], Docket ID Number EPA-HQ-OAR-2014-0451, in the public record for this rulemakingthe docketed memorandum “ Using ThirdParty Audits to Improve Compliance” for additional specificity regarding such third-party design features with sup porting studies, articles, and reports. 1. Definition and Characteristics of Independent Th ird-Party Compliance Verification Third-party compliance verification occurs when an independent third party verifies to a regulator tha t a regulated entity is meeting or conforming to one or more comp liance obligations (in the literature and other regulation s, the terms “certifier,” “auditor,” or “inspector” are also use d to describe such verifiers). Independent third-party programs a re distinct***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 205 of 324 from programs whereby regulated sources employ cont ractors or consultants, even if they are separate legal entiti es from the regulated facilities and are highly qualified. When contractors or consultants report to facilities directly, have other nonaudit business or relationships with the facilities , and/or the

facilities are able to control or influence the aud it reports’ form and/or content, this is not independent third- party verification but rather enhanced self-auditing 2. Third-Party Audit Program Considerations and Cha racteristics

Based on careful review of the literature 78 , the EPA believes independent third-party programs can be ef fective, but only if properly designed and overseen. The most cr itical considerations in designing successful third-party auditing programs are building in provisions and procedures for ensuring auditors are competent and independent. The EPA see ks comment on the suitability of an independent third-party verif ication program for landfills that includes the following d esign elements to ensure its effectiveness and integrity: the use of competent and independent auditors; accurate audits ; public transparency; and effective regulatory oversight. S ee also Docket ID Number EPA-HQ-OAR-2014-0451the docketed m emorandum “Using Third-Party Audits to Improve Compliance” for a review of

78 Lesley K. McAllister, Regulation by Third-Party Ve rification, 53 Boston C. L Rev. 1, 21-26 (Jan. 2012).***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 206 of 324 additional design features the EPA is considering a nd more

detailed information on the features listed below: a. A requirement that the auditing (verifying) firm , including any corporate parent and/or subsidiaries and the actual persons responsible for the audit, neither h ave had any prior business or family relationship with the firm being audited in the past five years, nor have worked on the development or implementation of the project/proces s subject to

the audit. b. A requirement that the auditing firm (including its corporate parent and/or subsidiaries, if any) is pr ohibited from engaging in any business transactions with the firm it is auditing for at least five years after the audit is completed. c. A requirement that the verifying entity and the specific auditors hold appropriate professional and educatio nal credentials issued by either the government entity that would otherwise review the plan or an independent profess ional organization (accreditation board) neither funded n or associated with the regulated sector. d. A requirement that the auditing firm share all d rafts and the final version of its audits with the govern ment entity before, or at the same time, as it shares them with the regulated entity.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 207 of 324 e. A requirement that appropriate auditing standard s and protocols be spelled out, including, if possible, b y reference to identified standards established by outside enti ties, e.g., International Organization for Standardization (ISO ), American National Standards Institute (ANSI), ASTM Internati onal (ASTM),

etc. f. A requirement that audit reports, including name s of key persons involved in the audits, be made accessible to the public subject to protecting confidential business informa tion (CBI) and national security information g. Requirements to ensure that the verifying firms operate with integrity, competence, and independence and th at the regulator audit, i.e., review or “backcheck,” inclu ding some number of on-site inspections, a significant percen tage (e.g., 10 percent) of the auditing firms and their audit r eports. The EPA is requesting comments regarding the approp riate professional and educational credentials requiremen ts for auditors. For example, should auditors be licensed professional engineers? In addition based upon comments received , the EPA also requests information concerning the costs asso ciated with third party certification design plans. The EPA is also considering defining more specifica lly what it means for an auditor to be independent, i.e., wh at potential conflicts of interest such as being employees of pa rent company,***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 208 of 324 affiliates, or vendors/contractors that are current ly working in the landfill industry, could exclude an auditor fro m qualifying as independent. Criteria for, and research on, comp etence and independence are discussed further below. The EPA is also considering allowing a person at th e facility who is a registered professional engineer to conduct the audit at the facility, i.e., first party/self a uditing, instead of requiring independent third party audits .. If selfauditing is authorized, the EPA seeks comment on ho w best to structure it to maximize auditor independence and a ccurate auditing outcomes. Under the U.S. CARB v. Hyundai M otor Company, et al. consent decree, for example, until the conse nt decrees corrective measures are fully implemented, the defe ndants must

audit their fleets to ensure that vehicles sold to the public

conform to the vehicles’ certification. The consent decree provides that the audit team will be in the United States, will be independent from the group that performed the or iginal certification work, and must perform their audits w ithout access to or knowledge of the defendants’ original certifi cation test data, which the consent decree-required audits are intended to

backcheck. 79 The EPA seeks comment as to whether similar

79 Press Release: http://yosemite.epa.gov/OPA/ADMPRESS.NSF/d0cf661852 5a9efb85257359003fb69d/155 19081fbf4002285257d8500477615!OpenDocument ; Detailed settlement info.: http://www2.epa.gov/enforcement/hyundai-and -kia-clean-air-act-***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 209 of 324 restrictions should be placed on any self-auditing conducted

under the MSW landfills Emission Guidelines. As another alternative approach, the EPA could requ ire auditors to have accreditation by a recognized accr editing body. Several of the examples that have already been prov ided of existing or proposed federal or state independent t hird party auditing programs in rules use this approach. The E PA thus seeks comment on whether third party auditors should be r equired to receive accreditation by a recognized accrediting b ody. The EPA

also seeks comment on the standards such accreditin g bodies should be required to meet, e.g., International Org anization for Standardization (ISO)/IEC 17011:2004(E), Conformity Assessments— General Requirements for Accreditation Bodies Accre diting Conformity Assessments Bodies (First Edition). There are advantages to third-party auditing, parti cularly with strong auditor competence and independence cri teria. According to the Center for Chemical Process Safety (CCPS), “Third-party auditors (typically, consulting compan ies who can provide experienced auditors) potentially provide t he highest degree of objectivity.” 80 The Administrative Conference of the United States (ACUS), in its Recommendation on Agen cy Use of

settlement ; Consent Decree: http://www2.epa.gov/sites/producti on/files/2014- 11/documents/hyundai-kia-cd.pdf 80 Guidelines for Risk Based Process Safety, March 20 07. CCPS. http://www.aiche.org/ccps/resources/publications/bo oks/guidelines-risk-basedprocess-safety***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 210 of 324 Third-Party Programs to Assess Regulatory Complianc e (December 6, 2012), found that, when well-designed and implem ented per the Recommendation, “[s]everal broad reasons support th e growing use of third-party programs in federal regulation.” Spe cifically, ACUS found that “...federal regulatory agencies are f aced with assuring the compliance of an increasing number of entities and products without a corresponding growth in agency r esources. Third-party programs may leverage private resources and expertise in ways that make regulation more effecti ve and less costly. In comparison with other regulatory approac hes, thirdparty programs may also enable more frequent compli ance assessment and more complete and reliable complianc e data” 81 A leading scholar on regulatory third-party programs likewise found that, when well-designed and implemented, “th ird-party

verification could furnish more and better data abo ut regulatory compliance” while providing additional compliance a nd resource savings benefits. 82 All independent third-party compliance verification programs establish criteria and standards for audit or

81 Administrative Conference of the United States (AC US); Administrative Conference Recommendation 2012-7; Agency Use of Thi rd-Party Programs to Assess Regulatory Compliance (Adopted December 6, 2 012) at 3-4. https://www.acus.gov/recommendation/agency-use-thir d-party-programs-assessregulatory-compliance

82 Lesley K. McAllister, Regulation by Third-Party Ve rification, 53 Boston C. L Rev. 1, 21-26 (Jan. 2012).***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 211 of 324 competence. Typically, such criteria and standards combine specified minimum levels of education, knowledge, e xperience, and training. Auditors should be knowledgeable and experienced with the facility type and processes being audited. The applicable recognized and generally accepted good e ngineering practices, trained or certified in proper third-par ty auditing techniques, and licensed professional engineers sho uld be employed where appropriate. The EPA seeks comment o n whether these criteria are appropriate and sufficient to en sure that auditors are competent to perform high-quality audi ting. 3. Public Disclosure/Transparency It is EPA policy that both the government and the p ublic have appropriate access to information about regula ted entities and their compliance status. This includes relevant information on the operation of any independent third-party pro grams. The

EPA seeks comment on what information associated wi th such a program for landfills should be publicly disclosed and how to

disclose it. 4. E-Reporting of Audit Reports and Certifications Pursuant to EPA’s Policy Statement on E-Reporting i n EPA Regulations (September 30, 2013), “[t]he Policy of the [EPA] is to [b]egin the regulatory development process with the assumption that all reporting will be electronic, u nless there is a compelling reason to use paper reporting. Cons istent with***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 212 of 324 that policy, the EPA is requesting comment on requi ring independent third-party auditors to provide their a udit reports and associated certification statements (see discus sion below) to EPA electronically and seeks comment on how to b est design the e-reporting system to facilitate its use by the regulated facilities and third-party auditors. 5. Facility and Third-Party Auditor Certification S tatements EPA’s experience shows that requiring a responsible corporate or third-party official to attest to self -monitoring, reporting, and third-party auditing can help ensure that appropriate officials are personally familiar with the reported information and reminds them of the penalties assoc iated with knowingly submitting false information. The EPA int ends to require such language for any third-party audit rep orts under these emission guidelines and requests comment on i ts wording. The EPA also requests comment on whether the Agency should, for this rule, require regulated facilities and/or thir d-party auditors to publicly post their certifications to t heir qualifications to conduct the audit and/or the accu racy and completeness of the audit reports. 6. Examples of Independent Third Party Programs in Other Rules Third party audits or other forms of compliance verification are also required by a variety of fina l or proposed EPA programs to promote compliance with regulatory standards.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 213 of 324 Examples of proposed or final federal environmental regulatory programs with built-in third-party verification inc lude the following rules and rulemakings:

• EPA CAA Renewable Fuel Standard (RFS) program: The RFS regulations include requirements for obligated part ies to: 1) meet annual attest engagement requirements using independent certified public accountants (the purpo se of attest engagements is to provide regulated parties an independent review of their compliance with both th e fuels requirements themselves as well as the regulated pa rty's internal systems to monitor and document compliance ); 2) submit independent third-party engineering reviews to the EPA before generating Renewable Identification Numb ers. 83

• EPA CAA wood stoves rule: Residential wood heaters (which include stoves) contribute significantly to particu late air pollution. Wood stove model lines that are in compl iance with the wood stoves rule are referred to as EPA-ce rtified wood stoves. The EPA's certification process requir es manufacturers to verify that each of their wood sto ve model lines meet a specific particulate emission limit by undergoing emission testing at an EPA-accredited laboratory. 84

F. Use of Portable Analyzers for Monitoring Oxygen In the proposed NSPS (79 FR 41796), as well as 40 C FR 60.37f(a)(2) of the proposed Emission Guidelines, l andfill owners or operators must use Method 3A or Method 3C when monitoring the oxygen and nitrogen levels at the we llhead,

unless an alternative test method is established. S everal

83 EPA, Renewable Fuel Standards (RFS), http://www.epa.gov/OTAQ/fuels/renewablefuels/.

84 EPA, Wood Heater Compliance Monitoring Program, https://www.federalregister.gov/articles/2015/03/16 /2015-03733/standards-ofperformance-for-new-residential-wood-heaters-new-re sidential-hydronicheaters-and***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 214 of 324 commenters on the proposed NSPS requested that the EPA specify that portable gas composition analyzers are an acce ptable alternative to Methods 3A or 3C, and noted that the se devices are commonly used in practice to measure wellhead p arameters and calibrated according to the manufacturer’s specific ations. Currently, approval of these analyzers are done on a case-bycase basis. In proposed 40 CFR part 60, subpart Cf, the EPA has not listed portable gas composition analyzers for d etermining oxygen or nitrogen levels. The EPA did not receive any data supporting these comments as to why the analyzers c ould not be calibrated according to Method 3A and maintains tha t proper calibration of portable gas composition analyzers i s important for generating accurate results. The EPA is request ing data or information on the use of a portable gas compositio n analyzer according to Method 3A. The EPA is also requesting data on other reference methods used for calibrating these analyz ers. XI. Impacts of Proposed Revisions For most Emission Guidelines, the EPA analyzes the impacts in the year the standard is implemented. As discuss ed in Section III.E, the EPA is proposing to extend the review pe riod for state plans. Assuming the Emission Guidelines are p romulgated in the summer of 2016, states have 9 months to prepare a state plan implementing the guidelines (March 2017) and the EP A has one year to review the plan (March 2018). If necessary, the state***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 215 of 324

has an additional 2 months to revise and submit a c orrected plan based on any comments from the EPA (May 2018). Conc urrently, the EPA must promulgate a federal plan within 6 months after the state plan is due, consistent with 60.27(d), or May 2018. So, the EPA-approved state plan and updated federal pla n implementing the Emission Guidelines are expected t o become effective in May 2018. While 2018 is the estimated implementation year, the proposed reporting and con trol

timeframe allows 3 months to submit the first NMOC emission report and then 30 months after exceeding the NMOC emission threshold before the GCCS is required to be install ed. So, the first year of controls under the proposed revisions would be

2021. The EPA is assessing impacts in year 2025 as a representative year for the landfills Emission Guid elines. While the year 2025 differs somewhat from the expected fi rst year of implementation for the Emission Guidelines (year 20 20), the number of existing landfills required to install co ntrols under the proposed 2.5/34 option in year 2025 is comparab le (within 2 percent of those required to control in the estimat ed first year of implementation. Further, year 2025 represents a year in which several of the landfills subject to control require ments have had to expand their GCCS according the expansion la g times set forth in proposed subpart Cf. The methodology for e stimating the***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 216 of 324 impacts of the Emission Guidelines is discussed in section V.B of this preamble and in the docketed memorandum “Re vised Methodology for Cost and Emission Impacts of Landfi ll Regulations (2015).” The results of applying this m ethodology to the population of existing landfills potentially su bject to each of the regulatory options are in the docketed memor andum “Revised Cost and Emission Impacts Resulting from t he Landfill EG Review (2015).” Table 3 of this preamble summari zes the

emission reductions and costs associated with the c ontrol options considered. A. What are the air quality impacts? This proposal would achieve nearly an additional 5 percent reduction in NMOC from existing landfills, or 2,770 Mg/yr, when compared to the baseline, as shown in Table 5 of th is preamble. The proposal would also achieve substantial reducti ons in methane emissions. These reductions are achieved by reducing the NMOC threshold from 50 Mg/yr to 34 Mg/yr as propose d at open

landfills. Table 5. Emission Reductions in 2025 for Existing L andfills Subject to Additional Controls Under Proposed Optio n 2.5/34 Parameter Quantity Baseline NMOC Emission Reductions(Mg) a 57,300 Proposed Incremental NMOC Emission Reductions (Mg) 2,770 Baseline Methane Emission Reductions (Mg) a 9,035,000 Proposed Incremental Methane Emission Reductions (Mg) 436,100***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 217 of 324 Parameter Quantity Baseline Methane Emission Reductions (million mtCO 2 e) a 226 Proposed Incremental Methane Emission Reductions (million mtCO 2 e) 10.9 % Emission Reduction from Proposal 5% below baselin e

a These are the reductions that would be achieved fr om existing landfills if 40 CFR part 60, subpart Cf retained the same gas collection and con trol requirements that are in 40 CFR part 60, subparts WWW and Cc. B. What are the water quality and solid waste impac ts? Leachate is the liquid that passes through the land filled waste and strips contaminants from the waste as the leachate percolates. Precipitation generates the vast majori ty of leachate volume. Installation of a gas collection s ystem will generate additional liquid, in the form of gas cond ensate, and

it will be routed to the same leachate treatment me chanisms in place for controlling precipitation-based leachate. Collected leachate can be treated on site or transported off site to

wastewater treatment facilities. Some landfills hav e received permits allowing for recirculation of leachate in t he landfill, which may further reduce the volume of leachate req uiring treatment. Additional liquid generated from gas con densate is not expected to be significant and insufficient dat a are available to estimate the increases in leachate res ulting from expanded gas collection and control requirements. The additional gas collection and control component s required by this proposal have finite lifetimes (ap proximately***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 218 of 324 15 years) and these pipes and wells will be capped or disposed

of at the end of their useful life. There are insuf ficient data to quantify the solid waste resulting from disposal of this

control infrastructure. Further, the incremental costs of control for the p roposal are not expected to have an appreciable market effe ct on the waste disposal costs, tipping fees, or the amount o f solid waste disposed in landfills because the costs for gas col lection represent a small portion of the overall costs to d esign, construct, and operate a landfill. There is insuffi cient information to quantify the effect increased gas co ntrol costs might have on the amount of solid waste disposed of in landfills versus other disposal mechanisms such as recycling, waste-toenergy, or composting. Note that elements of this p roposed rule— notably lowering the NMOC threshold to 34 Mg/yr—pro vide additional incentives to separate waste. C. What are the secondary air impacts? Secondary air impacts may include grid emissions fr om purchasing electricity to operate the GCCS componen ts, byproduct emissions from combustion of landfill gas i n flares or energy recovery devices, and offsets to conventiona l grid emissions from new landfill gas energy supply. The secondary air impacts are presented as net impa cts, considering both the energy demand and energy suppl y resulting***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 219 of 324 from the proposal. The methodology used to prepare the estimated secondary impacts for this preamble is discussed in the docketed memorandum “Estimating Secondary Impacts of the Lan dfills

Emission Guidelines Review. 2015.” While we do expect NOx and sulfur dioxide (SO 2 ) emission changes as a result of these guidelines, we expect these changes to be small and these changes have not been estimat ed. The net impacts were computed for CO 2 e. After considering the offsets from LFG electricity, the impacts of the proposal a re expected

to reduce CO 2 emissions by 238,000 metric tons per year. These

CO 2 emission reductions are in addition to the methane emission

reductions achieved from the direct destruction of methane in flares or engines presented in Table 3 of this prea mble. D. What are the energy impacts? The proposal is expected to have a very minimal imp act on energy supply and consumption. Active gas collectio n systems require energy to operate the blowers and pumps andthe proposal will increase the volume of landfill gas collected. When the least cost control is a flare, energy may be purcha sed from the grid to operate the blowers of the landfill gas col lection system. However, when the least cost control option is an engine, the engine may provide this energy to the g as control system and then sell the excess to the grid. Consid ering the***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 220 of 324 balance of energy generated and demanded from the e stimated least cost controls, the proposal is estimated to s upply 0.4 million megawatt hours (MWh) of additional energy p er year. E. What are the cost impacts? To meet the proposed emission limits, a landfill is expected to install the least cost control for comb usting the landfill gas. The cost estimates (described in sect ions V of this preamble) evaluated each landfill to determine whether a gas collection and flare or a gas collection with f lare and engine equipment would be least cost, after conside ring local power buyback rates and whether the quantity of lan dfill gas was sufficient to generate electricity. The control cos ts include the costs to install and operate gas collection inf rastructure such as wells, header pipes, blowers, and an enclos ed flare. For landfills where the least cost control option was a n engine, the costs also include the cost to install and operate one or more reciprocating internal combustion engines to conver t the landfill gas into electricity. Revenue from electri city sales was incorporated into the net control costs using s tate-specific data on wholesale purchase prices, where engines we re deemed to be the least cost control option. Testing and monit oring costs

at controlled landfills include the cost to conduct initial performance tests on the enclosed flare or engine c ontrol equipment, quarterly surface monitoring, continuous combustion***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 221 of 324 monitoring, and monthly wellhead monitoring. At unc ontrolled landfills, the testing and monitoring costs include calculation and reporting of NMOC emission rates.

The nationwide incremental annualized net cost for the proposal is $46.8 million, when using a 7 percent d iscount rate, of which $0.7 million is testing and monitoring cos ts. Table 6 of this preamble presents the costs. Table 6. Incremental Cost Impacts in 2025 for Exist ing Landfills Subject to Additional Controls under the Proposal

Option Total No. of Landfills Incurring Cost a Annualized

Control Cost Average

Annualized Revenue Average

Annualized Testing and Monitoring Cost Average

Net Total Annualized Cost Total Costs of Baseline ($2012) Baseline 2.5/50 (2.5 million Mg design capacity/50 Mg/yr NMOC) 785 1,700 1,408 7.3 299

Incremental Costs Above Baseline ($2012) Proposed Option 2.5/34 (2.5 million Mg design capacity/34 Mg/yr NMOC) 0 101 55.3 0.7 46.8

a At the baseline, 574 of the landfills are control ling in 2025 and an additional 211 landfills are expected to submit NMO C emission reports, but are not yet controlling for a total of 785. In the proposed option, the total landfills incurring cost are also 785, but the prop osal is estimated to require controls at 680 landfills and the remaining 105 landfills are expected to submit NMOC emission reports, but are n ot yet controlling. F. What are the economic impacts? Because of the relatively low net cost of the propo sed option compared to the overall size of the MSW indu stry, as well as the lack of appropriate economic parameters or m odel, the EPA***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 222 of 324 is unable to estimate the impacts of the options on the supply and demand for MSW landfill services. However, beca use of the relatively low incremental costs of the proposal, t he EPA does not believe the proposal would lead to substantial changes in supply and demand for landfill services or waste di sposal costs, tipping fees, or the amount of waste disposed in la ndfills. Hence, the overall economic impact of the proposal should be

minimal on the affected industries and their consum ers. G. What are the benefits? The proposal is expected to result in significant e missions reductions from existing MSW landfills. By lowering the NMOC emissions threshold to 34 Mg/yr, the proposal would achieve reductions of 2,770 Mg/yr NMOC and 436,100 Mg/yr me thane (10.9

million mtCO 2 e/yr). In addition, the proposal is expected to result in the net reduction of 238,000 Mg CO 2 , due to reduced demand for electricity from the grid as landfills g enerate electricity from landfill gas. This rule is expected to result in significant heal th and welfare benefits resulting from the climate benefit s due to anticipated methane and CO 2 reductions. Methane is a potent GHG that, once emitted into the atmosphere, absorbs ter restrial infrared radiation that contributes to increased gl obal warming and continuing climate change. Methane reacts in th e atmosphere***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 223 of 324 to form tropospheric ozone and stratospheric water vapor, both of which also contribute to global warming. When ac counting for the impacts of changing methane, tropospheric ozone , and stratospheric water vapor concentrations, the Inter governmental Panel on Climate Change (IPCC) 5th Assessment Repor t (2013)

found that historical emissions of methane accounte d for about 30 percent of the total current warming influence ( radiative forcing) due to historical emissions of greenhouse gases. Methane is therefore a major contributor to the cli mate change impacts described in section III.B of this preamble . The

remainder of this section discusses the methane red uctions expected from this proposed rule and the associatedmonetized

benefits. As discussed in section IV of this preamble, this rulemaking proposes several changes to the Emission Guidelines

for MSW landfills that would decrease methane emiss ions from this sector. Specifically, the proposed changes are expected to

reduce methane emissions from all landfills annuall y by about 436,100 metric tons of methane. We estimate the global social benefits of these met hane emission reductions using estimates of the social c ost of methane (SC-CH 4 ), a metric that estimates the monetary value of impacts associated with marginal changes in methane emissions in a given year. The SC-CH 4 estimates applied in this analysis were***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 224 of 324 developed by Marten et al. (2014) and are discussedin greater

detail below. A similar metric, the social cost of CO 2 (SC-CO 2 ), provides important context for understanding the Marten et a l. SC-CH 4

estimates. 85 The SC-CO 2 is a metric that estimates the monetary value of impacts associated with marginal changes i n CO 2 emissions in a given year. It includes a wide range of anticipated climate impacts, such as net changes in agricultural productivity and human health, property damage from increased flood risk, and changes in energy system costs, suc h as reduced costs for heating and increased costs for air condi tioning.

Estimates of the SC-CO 2 have been used by the EPA and other federal agencies to value the impacts of CO 2 emissions changes in benefit cost analysis for GHG-related rulemaking s since 2008.

The SC-CO 2 estimates were developed over many years, using the best science available, and with input from the public. Specifically, an interagency working group (IWG) th at included the EPA and other executive branch agencies and off ices used three integrated assessment models (IAMs) to develo p the SC-CO 2 estimates and recommended four global values for us e in

85 Previous analyses have commonly referred to the so cial cost of carbon dioxide emissions as the social cost of carbon or S CC. To more easily facilitate the inclusion of non-CO 2 GHGs in the discussion and analysis the more specific SC-CO 2 nomenclature is used to refer to the social cost o f CO 2 emissions.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 225 of 324 regulatory analyses. The SC-CO 2 estimates were first released in February 2010 and updated in 2013 using new version s of each

IAM. The 2010 SC-CO 2 Technical Support Document (TSD) provides a complete discussion of the methods used to develop these

estimates and the current SC-CO 2 TSD presents and discusses the 2013 update (including recent minor technical corre ctions to the estimates). 86

The SC-CO 2 TSDs discuss a number of limitations to the SCCO 2 analysis, including the incomplete way in which th e IAMs capture catastrophic and non-catastrophic impacts, their incomplete treatment of adaptation and technologica l change, uncertainty in the extrapolation of damages to high temperatures, and assumptions regarding risk aversi on. Current IAMs do not assign value to all of the important ph ysical, ecological, and economic impacts of climate change recognized in the climate change literature due to a lack of prec ise information on the nature of damages and because th e science incorporated into these models understandably lags behind the most recent research. Nonetheless, these estimates and the discussion of their limitations represent the best available

86 Both the 2010 SC-CO 2 TSD and the current TSD are available at: https://www.whitehouse.gov/omb/inforeg_regpol_agenc y_review https://www.whitehouse.gov/omb/oira/social-cost-of- carbon

.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 226 of 324

information about the social benefits of CO 2 reductions to inform benefit-cost analysis. The EPA and other age ncies continue to engage in research on modeling and valu ation of climate impacts with the goal to improve these esti mates, and

continue to consider feedback on the SC-CO 2 estimates from stakeholders through a range of channels, including public comments received on Agency rulemakings, a separate recent OMB public comment solicitation, and through regular in teractions with stakeholders and research analysts implementin g the SC-CO 2 methodology. See the docketed Regulatory Impacts An alysis (RIA)

for additional details. A challenge particularly relevant to this proposal is that

the IWG did not estimate the social costs of non-CO 2 GHG

emissions at the time the SC-CO 2 estimates were developed. In addition, the directly modeled estimates of the soc ial costs of

non-CO 2 GHG emissions previously found in the published

literature were few in number and varied considerab ly in terms of the models and input assumptions they employed 87 (EPA 2012). As a result, benefit-cost analyses informing U.S. f ederal rulemakings to date have not fully considered the m onetized

87 U.S. EPA. 2012. Regulatory Impact Analysis Final N ew Source Performance Standards and Amendments to the National Emissions Standards for Hazardous Air Pollutants for the Oil and Natural Gas Industry . Office of Air Quality Planning and Standards, Health and Environmental Im pacts Division. April. http://www.epa.gov/ttn/ecas/regdata/RIAs/oil_natura l_gas_final_neshap_nsps_ri a.pdf. Accessed March 30, 2015.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 227 of 324

benefits associated with CH 4 emissions mitigation. To understand the potential importance of monetizing non-CO 2 GHG emissions changes, the EPA has conducted sensitivity analysis in some of its past regulatory analyses using an estimate of t he GWP of CH 4 to convert emission impacts to CO 2 equivalents, which can then be valued using the SC-CO 2 estimates. This approach approximates the social cost of methane (SC-CH 4 ) using estimates of the SCCO 2 and the GWP of CH 4 . The published literature documents a variety of rea sons that directly modeled estimates of SC-CH 4 are an analytical improvement over the estimates from the GWP approxi mation approach. Specifically, several recent studies foun d that GWPweighted benefit estimates for CH 4 are likely to be lower than the estimates derived using directly modeled social cost estimates for these gases. 88 The GWP reflects only the relative integrated radiative forcing of a gas over 100 year s in comparison to CO 2 . The directly modeled social cost estimates

differ from the GWP-scaled SC-CO 2 because the relative differences in timing and magnitude of the warming between gases are explicitly modeled, the non-linear effects of t emperature change on economic damages are included, and rather than

88 See Waldhoff et al (2011); Marten and Newbold (201 2); and Marten et al. (2014).***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 228 of 324 treating all impacts over a hundred years equally, the modeled damages over the time horizon considered (2300 in t his case) are discounted to present value terms. A detailed discu ssion of the limitations of the GWP approach can be found in the RIA. In general, the commenters on previous rulemakings strongly encouraged the EPA to incorporate the monetized val ue of non-CO 2 GHG impacts into the benefit cost analysis. However they noted the challenges associated with the GWP approach, as discussed above, and encouraged the use of directly modeled e stimates of

the SC-CH 4 to overcome those challenges. Since these previous rulemakings, a paper by Marten et al. (2014) has provided the first set of published SC-C H 4 and social cost of nitrous oxide (SC-N 2 O) estimates in the peer-reviewed literature that are consistent with the modeling as sumptions underlying the SC-CO 2 estimates. 89 Specifically, the estimation approach of Marten et al. used the same set of thre e IAMs, five socioeconomic-emissions scenarios, equilibrium clim ate sensitivity distribution, three constant discount r ates, and aggregation approach used to develop the SC-CO 2 estimates.

89 Marten, A. L., E. A. Kopits, C. W. Griffiths, S. C . Newbold & A. Wolverton (2014). Incremental CH 4 and N 2 O mitigation benefits consistent with the U.S. Government's SC-CO 2 estimates, Climate Policy, DOI: 10.1080/14693062.2014.912981.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 229 of 324

The SC-CH 4 estimates from Marten, et al. (2014) are presented in Table 7 of this preamble. More detaile d discussion of the methodology, results, and a comparison to ot her published estimates can be found in the RIA and in Marten, et al.

Table 7. Social Cost of CH 4 , 2012 – 2050 a [in 2012$ per metric ton] (Source: Marten et al., 2014 b )

Year SC-CH 4

5% Average 3%

Average 2.5%

Average 3%

95 th percentile 2012 $430 $1000 $1400 $2800 2015 490 1100 1500 3000 2020 580 1300 1700 3500 2025 700 1500 1900 4000 2030 8 2 0 1700 2200 4 5 00 2035 970 1900 2500 5300 2040 1100 2200 2800 5900 2045 1300 2500 3000 6600 2050 1400 2700 3300 7200

a The values are emissions-year specific. Estimates using several discount rates are included because the literature shows tha t estimates of the SC-CO 2 (and SC-CH 4 ) are sensitive to assumptions about the discount r ate, and because no consensus exists on the appropriate rate to use in an intergenerational context (where costs and benefits are incurred by different generations). The fourth value is the 95th percenti le of the SC-CH 4 estimates across three models using a 3 percent discount rate . It is included to represent higher-than-expected impacts from tempera ture change further out in the tails of the SC-CH 4 distribution.

b The estimates in this table have been adjusted to r eflect the recent minor technical corrections to the SC-CO 2 estimates described above. See the RIA for more details.

The application of these directly modeled SC-CH 4 estimates from Marten et al. (2014) in a benefit-cost analysi s of a regulatory action is analogous to the use of the SC -CO 2 estimates. In addition, the limitations for the SC- CO 2 estimates***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 230 of 324 discussed above likewise apply to the SC-CH 4 estimates, given the consistency in the methodology. The EPA recently conducted a peer review of the app lication of the Marten, et al. (2014) non-CO 2 social cost estimates in regulatory analysis and received responses that sup ported this application. See the RIA for a detailed discussion. In light of the favorable peer review and past comm ents urging the EPA to value non-CO 2 GHG impacts in its rulemakings, the agency has used the Marten et al. (2014) SC-CH 4 estimates to value methane impacts expected from this proposed r ulemaking and

has included those benefits in the main benefits an alysis. The EPA seeks comments on the use of these directly mod eled estimates, from the peer-reviewed literature, for t he social

cost of non-CO 2 GHGs in this rulemaking.

The CH 4 benefits based on Marten et al. (2014) are presented for the year 2025. Applying this approach to the methane reductions estimated for this proposal, the 2025 methane benefits vary by discount rate and range from about $310 million to approximately $1.7 billion; the mean SC-CH 4 at the 3-percent discount rate results in an estimate of about $660 million in 2025, as presented in Table 8 of this preamble.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 231 of 324 Table 8. Estimated Global Benefits of CH 4 Reductions in 2025 [in millions, 2012$]

Million metric tons CH 4 Discount rate and Statistic

5% Average 3%

Average 2.5%

Average 3%

95 th percentile 0.44 $310 $660 $850 $1,700 The vast majority of this proposal’s climate-relate d

benefits are associated with methane reductions. Ad ditional climate-related benefits are expected from the prop osal’s secondary air impacts, specifically, a net reductio n in CO 2 emissions. Monetizing the net CO 2 reductions with the SC-CO 2 estimates described in this section yields benefits of $12 million in the year 2025 (average SC-CO 2 , 3 percent discount rate). See the RIA for more details. In addition to the limitation discussed above, and the referenced documents, there are additional impacts of individual GHGs that are not currently captured in the IAMs us ed in the directly modeled approach of Marten et al. (2014), and therefore not quantified for the rule. For example, the NMOC portion of LFG can contain a variety of air pollutants, includ ing VOC and various organic HAP. VOC emissions are precursors t o both PM 2.5 and ozone formation, while methane is a GHG and a p recursor to global ozone formation. These pollutants are associ ated with substantial health effects, welfare effects, and cl imate effects, which are discussed in section III.B of th is preamble.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 232 of 324 The ozone generated by methane, has important non-c limate impacts on agriculture, ecosystems, and human healt h. The RIA describes the specific impacts of methane as an ozo ne precursor in more detail and discusses studies that have esti mated monetized benefits of these methane generated ozone effects. The EPA continues to monitor developments in this area of research and seeks comment on the potential inclusion of hea lth impacts of ozone generated by methane in future regulatory analysis. Finally, this proposal is also expected to result i n improvements in air quality and resulting benefits to human health. With the data available, we are not able to provide health benefit estimates for the reduction in expos ure to HAP, ozone, and PM 2.5 for this rule. This is not to imply that there are no benefits of the rules; rather, it is a refle ction of the difficulties in modeling the direct and indirect impacts of the

reductions in emissions for this sector with the da ta currently

available. 90 In addition to health improvements, there will be

90 Previous studies have estimated the monetized benef its-per-ton of reducing VOC emissions associated with the effect that those emissions have on ambient PM 2.5 levels and the health effects associated with PM 2.5 exposure (Fann, Fulcher, and Hubbell, 2009). While these ranges of benefit-per-ton estimates can provide useful context, the geographic distribu tion of VOC emissions from the MSW landfills sector are not consistent with em issions modeled in Fann, Fulcher, and Hubbell (2009). In addition, the benef it-per-ton estimates for VOC emission reductions in that study are derived f rom total VOC emissions across all sectors. Coupled with the larger uncerta inties about the relationship between VOC emissions and PM 2.5 and the highly localized nature of air quality responses associated with HAP and VO C reductions, these factors lead us to conclude that the available VOC benefit-per-ton estimates***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 233 of 324 improvements in visibility effects, ecosystem effec ts, and

climate effects. Although we do not have sufficient information or m odeling available to provide quantitative estimates of the health benefits associated with HAP, ozone, and PM 2.5 reductions, we include a qualitative assessment of the health effe cts associated with exposure to HAP, ozone, and PM 2.5 in the RIA for this rule. These qualitative impact assessments are briefly summarized in section III.B of this preamble, but f or more detailed information, please refer to the RIA, whic h is

available in the docket. XII. Statutory and Executive Order Reviews

Additional information about these statues and Exec utiveOrders can be found at http://www2.epa.gov/lawsregulations/laws-and-executive-orders. A. Executive Order 12866: Regulatory Planning and R eview and Executive Order 13563: Improving Regulation and Reg ulatory

Review This action is an economically significant regulato ry action that was submitted to OMB for review. Any ch anges made in response to OMB recommendations have been documente d in the docket. The EPA prepared an economic analysis of th e potential

are not appropriate to calculate monetized benefits of these rules, even as a bounding exercise.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 234 of 324 costs and benefits associated with the proposed Emi ssion Guidelines. The analysis is documented in the RIA, which is available in docket EPA-HQ-OAR-2014-0451 and is bri efly summarized in section V.E of this preamble. B. Paperwork Reduction Act (PRA) The information collection requirements in the prop osed Emission Guidelines have been submitted for approva l to OMB under the PRA. The Information Collection Request ( ICR) document that the EPA prepared for the proposed Emission Gui delines has been assigned EPA ICR number [2522.01]. You can fin d a copy of the ICR in the docket for this rule, and it is brie fly

summarized here. The information required to be collected is necessa ry to identify the regulated entities subject to the prop osed rule and to ensure their compliance with the proposed Emissi on Guidelines. The recordkeeping and reporting require ments are mandatory and are being established under authority of CAA section 114 (42 U.S.C. 7414). All information other than emissions data submitted as part of a report to the agency for which a claim of confidentiality is made will be sa feguarded according to CAA section 114(c) and the EPA’s imple menting regulations at 40 CFR part 2, subpart B. Respondents/affected entities: Municipal solid wast e landfills that accepted waste after November 8, 198 7 and***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 235 of 324 commenced construction, reconstruction, or modifica tion on or before July 17, 2014. Respondent’s obligation to respond: Mandatory (40 C FR part 60, subpart Cf). Estimated number of respondents: 988 municipal soli d waste

landfills. Frequency of response: Initially, occasionally and annually. Total estimated burden: 621,947 hours (per year) fo r the responding facilities and 16,054 hours (per year) f or the agency. These are estimates for the average annual burden for the first 3 years after the rule is final. Burden i s defined at 5 CFR 1320.3(b). Total estimated cost: $41,755,793 (per year), which includes annualized capital or operation and mainte nance costs, for the responding facilities and $1,029,658 (per y ear) for the agency. These are estimates for the average annual cost for the first 3 years after the rule is final. An agency may not conduct or sponsor, and a person is not required to respond to, a collection of information unless it displays a currently valid OMB control number. The OMB control numbers for the EPA's regulations in 40 CFR are lis ted in 40 CFR part 9.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 236 of 324 Submit your comments on the agency’s need for this information, the accuracy of the provided burden es timates and any suggested methods for minimizing respondent bur den to the EPA using the docket identified at the beginning of this rule. You may also send your ICR-related comments to OMB’ s Office of Information and Regulatory Affairs via email to

oriaoira _submissions@omb.eop.gov, Attention: Desk Officer f or the EPA. Since OMB is required to make a decision c oncerning the ICR between 30 and 60 days after receipt, OMB must receive

comments no later than [insert date 30 days after publication in the Federal Register] . The EPA will respond to any ICR-related

comments in the final rule. C. Regulatory Flexibility Act (RFA) I certify that this action will not have a signific ant economic impact on a substantial number of small en tities under the RFA. This action will not impose any requiremen ts on small entities. Specifically, Emission Guidelines establi shed under CAA section 111(d) do not impose any requirements o n regulated entities and, thus, will not have a significant eco nomic impact upon a substantial number of small entities. After Emission Guidelines are promulgated, states and U.S. territo ries establish standards on existing sources, and it is those state requirements that could potentially impact small en tities.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 237 of 324 Our analysis here is consistent with the analysis o f the analogous situation arising when the EPA establishe s National Ambient Air Quality Standards (NAAQS), which do not impose any requirements on regulated entities. As here, any impact of a NAAQS on small entities would only arise when state s take subsequent action to maintain and/or achieve the NAAQS through their state implementation plans. See American Truc king Assoc. v. EPA, 175 F.3d 1029, 1043-45 (D.C. Cir. 1999) (NAAQS do not have significant impacts upon small entities becaus e NAAQS themselves impose no regulations upon small entitie s). Nevertheless, the EPA is aware that there is substa ntial interest in the rule among small entities. The EPA has conducted

stakeholder outreach as detailed in section XI.C an d XI.E of the preamble to the proposed Standards of Performance f or MSW Landfills (79 FR 41828-41829; July 17, 2014) and in sections XII.D and XII.E of this preamble. The EPA convened a Small Business Advocacy Review (SBAR) Panel in 2013 for t he landfills rulemaking. The EPA originally planned a review of the Emission Guidelines and NSPS in one action, but the actions were subsequently divided into separate rulemakings. The SBAR Panel evaluated the assembled materials and small-entity comments on issues related to the rule’s potential effects and significant alternative regulatory approaches. A copy of the Su mmary of Small Entity Outreach is available in the rulemakin g docket EPA-***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 238 of 324 HQ-OAR-2014-0451. While formulating the provisions of the rule, the EPA considered the input provided over the cour se of the stakeholder outreach as well as the input provided in the many public comments, and we have incorporated many of t he suggestions in this proposal. D. Unfunded Mandates Reform Act (UMRA) This action does not contain any unfunded mandate o f $100 million or more as described in UMRA, 2 U.S.C. 1531 –1538. The proposed Emission Guidelines apply to landfills tha t were constructed, modified, or reconstructed after Novem ber 8, 1987, and that commenced construction, reconstruction, or modification on or before July 17, 2014. Impacts resulting from the proposed Emission Guidelines are below the applicable thresh old. We note however, that the proposed Emission Guideli nes may significantly or uniquely affect small governments because small governments operate landfills. The EPA consulted wi th small governments concerning the regulatory requirements that might significantly or uniquely affect them. In developing this rule, the EPA consulted with small governments pursuant t o a plan

established under section 203 of the UMRA to addres s impacts of regulatory requirements in the rule that might sign ificantly or uniquely affect small governments. The EPA also hel d meetings as discussed in section XII.E of this preamble under F ederalism

consultations.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 239 of 324

E. Executive Order 13132: Federalism The EPA has concluded that the proposed Emission Gu idelines have federalism implications, because the rule impo ses substantial direct compliance costs on state or loc al governments, and the federal government will not pr ovide the funds necessary to pay those costs.

The EPA conducted a Federalism Consultation Outreac h Meeting on September 10, 2013. Due to interest in t hat meeting, additional outreach meetings were held on November 7, 2013 and November 14, 2013. With the pending proposal of the se Emission Guidelines, an additional Federalism outreach meeti ng was conducted on April 15, 2015. Participants included the National Governors’ Association, the National Conference of State Legislatures, the Council of State Governments, the National League of Cities, the U.S. Conference of Mayors, th e National Association of Counties, the International City/Cou nty Management Association, the National Association of Towns and Townships, the County Executives of America, the En vironmental Council of States, National Association of Clean Ai r Agencies,

Association of State and Territorial Solid Waste Ma nagement Officials, environmental agency representatives fro m 43 states, and approximately 60 representatives from city and county governments. Concerns raised during the consultatio ns include: implementation concerns associated with shortening of gas***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 240 of 324 collection system installation and/or expansion tim eframes, concerns regarding significant lowering of the desi gn capacity or emission thresholds, the need for clarifications associated with wellhead operating parameters and the need for consistent, clear and rigorous surface monitoring requirements.

F. Executive Order 13175: Consultation and Coordina tion with

Indian Tribal Governments This action has tribal implications. However, it wi ll neither impose substantial direct compliance costs on federally recognized tribal governments, nor preempt tribal l aw. The database used to estimate impacts of the proposed 4 0 CFR part 60, subpart Cf identified one tribe, the Salt River PimaMaricopa Indian Community, which owns three landfil ls potentially subject to the proposed Emission Guidel ines. One of these landfills is open, the Salt River Landfill, a nd is already controlling emissions under the current NSPS/EG fra mework, so while subject to this subpart, the costs of this pr oposal are

not substantial. The two other landfills are closedand anticipated to meet the definition of the closed la ndfill subcategory. One of the closed landfills, the Tri C ities Landfill, is already controlling emissions under th e current NSPS/EG framework and will not incur substantial ad ditional compliance costs under Cf. The other landfill, Nort h Center***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 241 of 324 Street Landfill, is not estimated to install contro ls under the current NSPS/EG framework.

G. Executive Order 13045: Protection of Children fr om Environmental Health Risks and Safety Risks The EPA interprets Executive Order 13045 as applyin g only to those regulatory actions that concern environmen tal health or safety risks that the EPA has reason to believe may disproportionately affect children, per the definit ion of “covered regulatory action” in section 2-202 of the Executive

Order. The proposed Emission Guidelines are not subject to Executive Order 13045 because they do not concern a n environmental health risk or safety risk. We also n ote that the methane and NMOC reductions expected from the propo sed Emission Guidelines will have positive health effects includ ing for children as previously discussed in section XII.G o f this preamble. H. Executive Order 13211: Actions that Significantl y Affect Energy Supply, Distribution, or Use This action is not a “significant energy action” be cause it is not likely to have a significant adverse effect on the supply, distribution, or use of energy. Further, we have concluded that the proposed Emission Guidelines are not likely to have any adverse energy effects because the ener gy demanded***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 242 of 324 to operate these control systems will be offset by additional energy supply from landfill gas energy projects. I. National Technology Transfer and Advancement Act The proposed Emission Guidelines involve technical standards. For the proposed Emission Guidelines, th e EPA has decided to use EPA Methods 2, 2E, 3, 3A, 3C, 21, 25 , 25A, and 25C of 40 CFR part 60, appendix A. While the EPA id entified 10 VCS as being potentially applicable (ANSI/ASME PTC 19-10-1981 Part 10, ASME B133.9-1994 (2001), ISO 10396:1993 (2 007), ISO 12039:2001, ASTM D5835-95 (2013), ASTM D6522-11, CAN/CSA Z223.2- M86 (1999), ASTM D6060-96 (2009), ISO 14965:2000(E) , EN 12619(1999)), the agency decided not to use these m ethods. The

EPA determined that the 10 candidate VCS identifiedfor measuring emissions of pollutants or their surrogat es subject to emission standards in the rule would not be practic al due to lack of equivalency, documentation, validation data , and other important technical and policy considerations. The agency identified no such standards for Methods 2E, 21, an d 25C. The EPA’s review, including review of comments for thes e 10 methods, is documented in the memorandum, “Voluntary Consens us Standard Results for Emission Guidelines and Compliance Time s for Municipal Solid Waste Landfills” in the docket for this rulemaking (EPA-HQ-OAR-2014-0451).***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 243 of 324

J. Executive Order 12898: Federal Actions to Addres s Environmental Justice in Minority Populations and L ow-Income Populations

The EPA believes the human health or environmental risk addressed by the proposed Emission Guidelines will not have potential disproportionately high and adverse human health or environmental effects on minority, low-income, or i ndigenous populations because the proposed subpart would redu ce emissions of landfill gas, which contains both nonmethane org anic compounds and methane. These avoided emissions will improve air quality and reduce public health and welfare effect s associated with exposure to landfill gas emissions. The result s of the proximity analysis conducted for the proposed Emiss ion Guidelines are located in the April 22, 2015 docume nt entitled, “2015 Environmental Justice Screening Report for Mu nicipal Solid Waste Landfills,” a copy of which is available in t he docket (Docket ID No. EPA–HQ–OAR–2003–0215).***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review***

Emission Guidelines and Compliance Times and Supple mental Standards of

Performance for Municipal Solid Waste Landfills

Page 244 of 324 List of Subjects in 40 CFR Part 60 Environmental protection, Administrative practice a nd procedure, Air pollution control, Reporting and rec ordkeeping requirements.

Dated:

Gina McCarthy, Administrator.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 245 of 324 For the reasons set forth in the preamble, EPA prop oses to

amend 40 CFR Part 60 as follows:

PART 60 STANDARDS OF PERFORMANCE FOR NEW STATIONARYSOURCES

1. The authority citation for part 60 continues to read as follows:

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

2. Part 60 is amended by adding Subpart Cf to read as follows:

Subpart Cf—Emission Guidelines and Compliance Times for Municipal Solid Waste Landfills Contents § 60.30f Scope and delegated authorities. § 60.31f Designated facilities. § 60.32f Compliance times. § 60.33f Emission Guidelines for municipal solid wa ste landfill emissions. § 60.34f Operational standards. § 60.35f Test methods and procedures. § 60.36f Compliance provisions. § 60.37f Monitoring of operations. § 60.38f Reporting guidelines. § 60.39f Recordkeeping guidelines. § 60.40f Specifications for active collection systems. § 60.41f Definitions.

Subpart Cf—Emission Guidelines and Compliance Times for Municipal Solid Waste Landfills***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 246 of 324 § 60.30f Scope and delegated authorities. This subpart establishes Emission Guidelines and co mpliance times for the control of designated pollutants from certain designated municipal solid waste (MSW) landfills in accordance with section 111(d) of the Clean Air Act and subpar t B. (a) If you are the Administrator of an air quality program in a State or United States protectorate with one o r more existing MSW landfills that commenced construction, modification, or reconstruction on or before July 1 7, 2014, you must submit a State plan to the U.S. Environmental Protection Agency (EPA) that implements the Emission Guideline s contained in this subpart. The requirements for State plans a re specified in subpart B of this part. (b) You must submit a State plan to EPA by [insert date 9 months after the final rule is published in the Fed eral Register]. (c) The following authorities will not be delegatedto state, local, or tribal agencies: (1) Approval of alternative methods to determine th e NMOC concentration or a site-specific methane generation rate constant (k). (2) [Reserved] § 60.31f Designated facilities.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 247 of 324 (a) The designated facility to which these Emission Guidelines apply is each existing MSW landfill for which construction, reconstruction, or modification was c ommenced on or before July 17, 2014. (b) Physical or operational changes made to an exis ting MSW landfill solely to comply with an emission guidelin e are not

considered a modification or reconstruction and wou ld not subject an existing MSW landfill to the requirement s of a standard of performance for new MSW landfills. (c) For purposes of obtaining an operating permit u nder title V of the Clean Air Act, the owner or operator of an MSW landfill subject to this subpart with a design capa city less than 2.5 million megagrams or 2.5 million cubic met ers is not subject to the requirement to obtain an operating p ermit for the landfill under part 70 or 71 of this chapter, unles s the landfill is otherwise subject to either part 70 or 71. For purposes of submitting a timely application for an operating permit under part 70 or 71, the owner or operator o f an MSW landfill subject to this subpart with a design capa city greater than or equal to 2.5 million megagrams and 2.5 mill ion cubic meters on the effective date of EPA approval of the State's program under section 111(d) of the Clean Air Act, and not otherwise subject to either part 70 or 71, becomes subject to the requirements of §§ 70.5(a)(1)(i) or 71.5(a)(1)( i) of this***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 248 of 324 chapter 90 days after the effective date of such se ction 111(d) program approval, even if the design capacity repor t is

submitted earlier. (d) When an MSW landfill subject to this subpart is closed as defined in this subpart, the owner or operator i s no longer subject to the requirement to maintain an operating permit under part 70 or 71 of this chapter for the landfill if t he landfill is not otherwise subject to the requirements of eit her part 70 or 71 and if either of the following conditions are met: (1) The landfill was never subject to the requireme nt to install and operate a gas collection and control sy stem under § 60.33f; or (2) The landfill meets the conditions for control s ystem removal specified in § 60.33f(f). (e) When an MSW landfill subject to this subpart is in the closed landfill subcategory, the owner or operator is not subject to the following reports of this subpart, p rovided the owner or operator submitted these reports under the provisions of 40 CFR part 60, subpart WWW; 40 CFR part 62, sub part GGG; or a state plan implementing 40 CFR part 60, subpart C c on or before [ insert date of publication in the Federal Register ]: (1) Initial design capacity report specified in §§ 60.33f(d) and 60.38f(a)***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 249 of 324 (2) Initial or subsequent NMOC emission rate report specified in §§ 60.33f(e) and 60.38f(c), provided t hat the most recent NMOC emission rate report indicated the NMOC emissions were below 50 Mg/yr. (3) Collection and control system design plan speci fied in § 60.38f(d). (4) Closure report specified in § 60.38f(f). (5) Equipment removal specified in § 60.38f(g). (6) Initial annual report specified in § 60.38f(h). (7) Initial performance test report in § 60.38f(i). § 60.32f Compliance times. Planning, awarding of contracts, installing, and st arting up MSW landfill air emission collection and control equipment that is capable of meeting the Emission Guidelines under § 60.33f must be completed within 30 months after the date an NMOC emission rate report shows NMOC emissions equal or exceed 34 megagrams per year (50 megagrams per year for the c losed landfill subcategory) or within 30 months after the date Tier 4 surface emissions monitoring shows a surface emissi on concentration of 500 parts per million methane or g reater. § 60.33f Emission Guidelines for municipal solid wa ste landfill

emissions. (a) Landfills. For approval, a State plan must requ ire each owner or operator of an MSW landfill having a desig n capacity***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 250 of 324 greater than or equal to 2.5 million megagrams by m ass and 2.5 million cubic meters by volume to collect and contr ol MSW

landfill emissions at each MSW landfill that meets the following

conditions: (1) The landfill has accepted waste at any time sin ce November 8, 1987, or has additional design capacity available for future waste deposition. (2) The landfill commenced construction, reconstruc tion, or modification on or before July 17, 2014. (3) The landfill has an NMOC emission rate greater than or equal to 34 megagrams per year or the Tier 4 surfac e emissions report shows a surface emission concentration of 50 0 parts per million methane or greater. (4) A landfill in the closed landfill subcategory t hat has an NMOC emission rate greater than or equal to 50 m egagrams per year or the Tier 4 surface emissions report shows a surface emission concentration of 500 parts per million met hane or greater. (b) Collection system. For approval, a State plan m ust include provisions for the installation of a collec tion and control system meeting the requirements in paragrap hs (b)(1) through (b)(3) and (c) of this section at each MSW landfill meeting the conditions in paragraph (a) of this sec tion.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 251 of 324 (1) Install and start up a collection and control s ystem that captures the gas generated within the landfill within 30

months after: (i) The first annual report in which the emission r ate equals or exceeds 34 megagrams per year, unless Tie r 2 or Tier 3 sampling demonstrates that the emission rate is les s than 34 megagrams per year, as specified in § 60.38f(c)(5)( i) or (ii), (ii) The emission rate at a landfill in the closed landfill subcategory equals or exceeds 50 megagrams per year , unless Tier 2 or Tier 3 sampling demonstrates that the emission rate is less than 50 megagrams per year, as specified in § 60.38f(c)(5)(iv)(A) or (B), or (iii) The Tier 4 surface emissions report shows tha t surface methane emissions are below 500 parts per m illion methane for four consecutive quarters, as specifiedin § 60.38f(c)(5)(iii). (2) An active collection system must: (i) Be designed to handle the maximum expected gas flow

rate from the entire area of the landfill that warr ants control over the intended use period of the gas control sys tem equipment. (ii) Collect gas from each area, cell, or group of cells in

the landfill in which the initial solid waste has b een placed***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 252 of 324 for a period of 5 years or more if active; or 2 yea rs or more if closed or at final grade. (iii) Collect gas at a sufficient extraction rate. (iv) Be designed to minimize offsite migration of subsurface gas. (3) A passive collection system must: (i) Comply with the provisions specified in paragra phs (b)(2)(i), (ii), and (iv) of this section. (ii) Be installed with liners on the bottom and all sides in all areas in which gas is to be collected. The l iners must be installed as required under § 258.40. (c) Control system. For approval, a State plan must include provisions for the control of the gas collected fro m within the landfill through the use of control devices meeting the following requirements, except as provided in § 60. 24. (1) A non-enclosed flare designed and operated in accordance with the parameters established in § 60. 18 except as noted in § 60.37f(c); or (2) A control system designed and operated to reduc e NMOC by 98 weight percent; or when an enclosed combustio n device is used for control, to either reduce NMOC by 98 weigh t percent or reduce the outlet NMOC concentration to less than 2 0 parts per million by volume, dry basis as hexane at 3 percent oxygen or less. The reduction efficiency or concentration in parts per***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 253 of 324 million by volume must be established by an initial performance test to be completed no later than 180 days after t he initial startup of the approved control system using the te st methods specified in § 60.35f(d). The performance test is n ot required for boilers and process heaters with design heat in put capacities equal to or greater than 44 megawatts th at burn landfill gas for compliance with this subpart. (i) If a boiler or process heater is used as the co ntrol device, the landfill gas stream must be introduced into the

flame zone. (ii) The control device must be operated within the parameter ranges established during the initial or most recent performance test. The operating parameters to be mo nitored are specified in § 60.37f. (iii) For the closed landfill subcategory, the init ial or most recent performance test conducted to comply wi th 40 CFR part 60, subpart WWW; 40 CFR part 62, subpart GGG; or a state plan implementing 40 CFR part 60, subpart Cc on or before [ insert date of publication in the Federal Register ] is sufficient for compliance with this subpart. (3) Route the collected gas to a treatment system t hat processes the collected gas for subsequent sale or beneficial use such as fuel for combustion, production of vehi cle fuel, production of high-Btu gas for pipeline injection, or use as a***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 254 of 324 raw material in a chemical manufacturing process. V enting of treated landfill gas to the ambient air or combusti on in a flare is not allowed under this option. (If flares are us ed, they must meet the requirements in paragraphs (c)(1) or (c)(2 ) of this section.) (4) All emissions from any atmospheric vent from th e gas treatment system are subject to the requirements of paragraph (b) or (c) of this section. For purposes of this su bpart, atmospheric vents located on the condensate storage tank are not part of the treatment system and are exempt from th e requirements of paragraph (b) or (c) of this sectio n. (d) Design capacity. For approval, a State plan mus t require each owner or operator of an MSW landfill h aving a design capacity less than 2.5 million megagrams by mass or 2.5 million cubic meters by volume to submit an initial design capacity report to the Administrator as provided in § 60.38f(a). The landfill may calculate design capacity in eithe r megagrams or cubic meters for comparison with the exemption v alues. Any density conversions must be documented and submitte d with the report. Submittal of the initial design capacity re port fulfills the requirements of this subpart except as providedin paragraphs (d)(1) and (d)(2) of this section. (1) The owner or operator must submit an amended de sign capacity report as provided in § 60.38f(b). [Guidan ce: Note that***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 255 of 324 if the design capacity increase is the result of a modification, as defined in this subpart, that was commenced afte r July 17, 2014, the landfill will become subject to subpart X XX of this part instead of this subpart. If the design capacit y increase is the result of a change in operating practices, dens ity, or some other change that is not a modification as defined in this subpart, then the landfill remains subject to this subpart.] (2) When an increase in the maximum design capacity of a landfill with an initial design capacity less than 2.5 million megagrams or 2.5 million cubic meters results in a revised maximum design capacity equal to or greater than 2. 5 million megagrams and 2.5 million cubic meters, the owner o r operator must comply with paragraph (e) of this section. (e) Emissions. For approval, a State plan must requ ire each owner or operator of an MSW landfill having a desig n capacity equal to or greater than 2.5 million megagrams and 2.5 million

cubic meters to either install a collection and con trol system as provided in paragraphs (b) and (c) of this secti on or calculate an initial NMOC emission rate for the lan dfill using the procedures specified in § 60.35f(a). The NMOC e mission rate must be recalculated annually, except as provided i n § 60.38f(c)(3). (1) If the calculated NMOC emission rate is less th an 34 megagrams per year, the owner or operator must:***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 256 of 324 (i) Submit an annual NMOC emission rate report acco rding to § 60.38f(c); and (ii) Recalculate the NMOC emission rate annually us ing the procedures specified in § 60.35f(a) until such time as the calculated NMOC emission rate is equal to or greate r than 34 megagrams per year, or the landfill is closed. (A) If the NMOC emission rate, upon initial calcula tion or annual recalculation, is equal to or greater than 3 4 megagrams per year, the owner or operator must either: submit a gas collection and control system design plan as specif ied in § 60.38f(d) and install a collection and control syst em as provided in paragraphs (b) and (c) of this section; calculate NMOC emissions using the next higher tier in § 60.3 5f; or conduct a surface emission monitoring demonstration using the procedures specified in § 60.35f(a)(6). (B) If the landfill is permanently closed, a closur e report must be submitted to the Administrator as provided in § 60.38f(f), except for exemptions allowed under 60.3 1f(e)(4). (C) For the closed landfill subcategory, if the mos t recently calculated NMOC emission rate is equal to or greater than 50 megagrams per year, the owner or operator m ust either: submit a gas collection and control system design p lan as specified in § 60.38f(d), except for exemptions all owed under 60.31f(e)(3), and install a collection and control system as***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 257 of 324 provided in paragraphs (b) and (c) of this section; calculate NMOC emissions using the next higher tier in § 60.3 5f; or conduct a surface emission monitoring demonstration using the procedures specified in § 60.35f(a)(6). (2) If the calculated NMOC emission rate is equal t o or greater than 34 megagrams per year using Tier 1, 2, or 3 procedures, the owner or operator must either: subm it a collection and control system design plan prepared by a professional engineer to the Administrator within 1 year as specified in § 60.38f(d); calculate NMOC emissions using a higher tier in § 60.35f; or conduct a surface emiss ion monitoring demonstration using the procedures speci fied in § 60.35f(a)(6). (3) For the closed landfill subcategory, if the cal culated NMOC emission rate is equal to or greater than 50 m egagrams per year using Tier 1, 2, or 3 procedures, the owner or operator must either: submit a collection and control system design plan prepared by a professional engineer to the Administ rator within 1 year as specified in § 60.38f(d), except for exemptions allowed under 60.31f(e)(3); calculate NMOC emission s using a higher tier in § 60.35f; or conduct a surface emiss ion monitoring demonstration using the procedures speci fied in § 60.35f(a)(6).***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 258 of 324 (f) Removal criteria. The collection and control sy stem may be capped or removed if the criteria in paragraph ( f)(1), (f)(2), and either (f)(3), (f)(4), or (f)(5) of thi s section are

met: (1) The landfill is closed or an area of an open la ndfill is closed as defined in § 60.41f. A closure report must be submitted to the Administrator as provided in § 60. 38f(f); (2) The collection and control system must have bee n in operation a minimum of 15 years or the landfill own er or operator must demonstrate that the GCCS will be una ble to operate for 15 years due to declining gas flow; and (3) The landfill or closed area demonstrates for fo ur consecutive quarters that there are no surface emis sions of 500 parts per million or greater as determined using pr ocedures specified in § 60.36f(d); (4) Following the procedures specified in § 60.35f( b), the

calculated NMOC emission rate at the landfill must be less than 34 megagrams per year on three successive test date s. The test dates must be no less than 90 days apart, and no mo re than 180 days apart; or (5) For the closed landfill subcategory, following the procedures specified in § 60.35f(b), the calculated NMOC

emission rate at the landfill must be less than 50 megagrams per***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 259 of 324 year on three successive test dates. The test dates must be no less than 90 days apart, and no more than 180 days apart. § 60.34f Operational standards. For approval, a State plan must include provisions for the operational standards in this section for an MSW la ndfill with a gas collection and control system used to comply wi th the provisions of § 60.33f(b) and (c). Each owner or op erator of an MSW landfill with a gas collection and control syst em used to comply with the provisions of § 60.33f(b) must: (a) Operate the collection system such that gas is collected from each area, cell, or group of cells i n the MSW landfill in which solid waste has been in place for : (1) 5 years or more if active; or (2) 2 years or more if closed or at final grade; (b) Operate the collection system with negative pre ssure at each wellhead except under the following conditions : (1) A fire or increased well temperature. The owner or operator must record instances when positive pressu re occurs in

efforts to avoid a fire. These records must be subm itted with the annual reports as provided in § 60.38f(h)(1); (2) Use of a geomembrane or synthetic cover. The ow ner or operator must develop acceptable pressure limits in the design plan;***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 260 of 324 (3) A decommissioned well. A well may experience a static positive pressure after shut down to accommodate fo r declining flows. All design changes must be approved by the A dministrator as specified in § 60.38f(d); (c) [Reserved] (d) Operate the collection system so that the metha ne concentration is less than 500 parts per million ab ove background at the surface of the landfill. To deter mine if this level is exceeded, the owner or operator must condu ct surface testing around the perimeter of the collection area and along a pattern that traverses the landfill at no more than 30-meter

intervals and where visual observations indicate el evated concentrations of landfill gas, such as distressed vegetation and cracks or seeps in the cover and all cover pene trations. Thus, the owner or operator must monitor any openin gs that are

within an area of the landfill where waste has been placed and a gas collection system is required. The owner or ope rator may establish an alternative traversing pattern that en sures equivalent coverage. A surface monitoring design pl an must be developed that includes a topographical map with th e monitoring route and the rationale for any site-specific devia tions from the 30-meter intervals. Areas with steep slopes or other dangerous areas may be excluded from the surface te sting.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 261 of 324 (e) Operate the system such that all collected gase s are vented to a control system designed and operated in compliance with § 60.33f(c). In the event the collection or co ntrol system is not operating, the gas mover system must be shut down and all valves in the collection and control system contrib uting to venting of the gas to the atmosphere must be closedwithin 1 hour; and (f) Operate the control system at all times when th e collected gas is routed to the system. (g) If monitoring demonstrates that the operational requirements in paragraphs (b) or (d) of this secti on are not met, corrective action must be taken as specified i n § 60.36f(a)(3) through (4) or § 60.36f(c). If correct ive actions are taken as specified in § 60.36f, the monitored e xceedance is not a violation of the operational requirements in this section. § 60.35f Test methods and procedures. For approval, a State plan must include provisions in this

section to calculate the landfill NMOC emission rat e or to conduct a surface emission monitoring demonstration

. (a)(1) The landfill owner or operator must calculat e the NMOC emission rate using either the equation provid ed in paragraph (a)(1)(i) of this section or the equation provided in paragraph (a)(1)(ii) of this section. Both equation s may be used if the actual year-to-year solid waste acceptance r ate is known,***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 262 of 324 as specified in paragraph (a)(1)(i) of this section , for part of the life of the landfill and the actual year-to-yea r solid waste acceptance rate is unknown, as specified in paragra ph (a)(1)(ii) of this section, for part of the life of the landfi ll. The values to be used in both equations are 0.05 per ye ar for k, 170 cubic meters per megagram for Lo, and 4,000 parts p er million by

volume as hexane for the CNMOC. For landfills locat ed in geographical areas with a 30-year annual average pr ecipitation of less than 25 inches, as measured at the nearest representative official meteorologic site, the k va lue to be used is 0.02 per year. (i) The following equation must be used if the actu al yearto-year solid waste acceptance rate is known.

 = ∑ 2  (   )( )(3.6		10  )   Where:

MNMOC = Total NMOC emission rate from the landfill,

megagrams per year. k = Methane generation rate constant, year−1. Lo = Methane generation potential, cubic meters per

megagram solid waste. Mi = Mass of solid waste in the ith section, megagr ams. ti = Age of the ith section, years. CNMOC = Concentration of NMOC, parts per million by volume

as hexane. 3.6 × 10 −9 = Conversion factor.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 263 of 324 The mass of nondegradable solid waste may be subtra cted from the total mass of solid waste in a particular section of the landfill when calculating the value for Mi if d ocumentation

of the nature and amount of such wastes is maintain ed. (ii) The following equation must be used if the act ual year-to-year solid waste acceptance rate is unknown

. MNMOC = 2LoR (e −kc−e−kt) CNMOC(3.6 × 10−9 )

Where:

MNMOC = Mass emission rate of NMOC, megagrams per y ear. Lo = Methane generation potential, cubic meters per

megagram solid waste. R = Average annual acceptance rate, megagrams per y ear. k = Methane generation rate constant, year−1. t = Age of landfill, years. CNMOC = Concentration of NMOC, parts per million by volume

as hexane. c = Time since closure, years; for an active landfi ll c

= 0 and e−kc = 1. 3.6 × 10 −9 = Conversion factor. The mass of nondegradable solid waste may be subtra cted from the total mass of solid waste in a particular section of the landfill when calculating the value of R, if do cumentation

of the nature and amount of such wastes is maintain ed. (2) Tier 1. The owner or operator must compare the

calculated NMOC mass emission rate to the standard of 34

megagrams per year.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 264 of 324 (i) If the NMOC emission rate calculated in paragra ph (a)(1) of this section is less than 34 megagrams pe r year, then the owner or operator must submit an NMOC emission rate report according to § 60.38f(c), and must recalculate the NMOC mass emission rate annually as required under § 60.33f(e ). (ii) If the NMOC emission rate calculated in paragr aph (a)(1) of this section is equal to or greater than 34 megagrams per year, then the landfill owner or operator must either: (A) Submit a gas collection and control system desi gn plan as specified in § 60.38f(d) within 1 year and insta ll and operate a gas collection and control system accordi ng to § 60.33f(b) and (c) within 30 months; (B) Determine a site-specific NMOC concentration an d recalculate the NMOC emission rate using the Tier 2 procedures provided in paragraph (a)(3) of this section; (C) Determine a site-specific methane generation ra te

constant and recalculate the NMOC emission rate usi ng the Tier 3 procedures provided in paragraph (a)(4) of this sec tion; or (D) Conduct a surface emission monitoring demonstra tion using the Tier 4 procedures specified in paragraph (a)(6) of

this section. (3) Tier 2. The landfill owner or operator must det ermine the site-specific NMOC concentration using the foll owing sampling procedure. The landfill owner or operator must install***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 265 of 324 at least two sample probes per hectare of landfill surface that has retained waste for at least 2 years. If the lan dfill is larger than 25 hectares in area, only 50 samples ar e required. The sample probes should be located to avoid known areas of nondegradable solid waste. The owner or operator mu st collect and analyze one sample of landfill gas from each pr obe to determine the NMOC concentration using Method 25 or 25C of appendix A of this part. Taking composite samples f rom different probes into a single cylinder is allowed; however, equal sample volumes must be taken from each probe. For each composite, the sampling rate, collection times, beginning and endi ng cylinder vacuums, or alternative volume measurements must be recorded to verify that composite volumes are equal. Composite sample

volumes should not be less than one liter unless ev idence can be provided to substantiate the accuracy of smaller vo lumes. Terminate compositing before the cylinder approache s ambient pressure where measurement accuracy diminishes. If more than the required number of samples is taken, all samples mu st be used in the analysis. The landfill owner or operator must d ivide the NMOC concentration from Method 25 or 25C of appendi x A of this part by six to convert from CNMOC as carbon to CNMO C as hexane. If the landfill has an active or passive gas remova l system in place, Method 25 or 25C samples may be collected fr om these systems instead of surface probes provided the remo val system***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 266 of 324 can be shown to provide sampling as representative as the two sampling probe per hectare requirement. For active collection systems, samples may be collected from the common h eader pipe. The sample location on the common header pipe must be before any gas moving, condensate removal, or treatment system equipment. For active collection systems, a minimum of three s amples must be collected from the header pipe. (i) Within 60 days after the date of determining th e NMOC concentration and corresponding NMOC emission rate, the owner or operator must submit the results according to § 60. 38f(j). (ii) The landfill owner or operator must recalculat e the NMOC mass emission rate using the equations provide d in paragraph (a)(1)(i) or (a)(1)(ii) of this section u sing the average site-specific NMOC concentration from the c ollected samples instead of the default value provided in pa ragraph (a)(1) of this section. (iii) If the NMOC mass emission rate is less than 3 4 megagrams per year, then the owner or operator must submit an NMOC emission rate report according to § 60.38f(c), and must recalculate the NMOC mass emission rate annually as required under § 60.33f(e). The site-specific NMOC concentra tion must be retested every 5 years using the methods specified in this

section.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 267 of 324 (iv) If the NMOC mass emission rate as calculated u sing the Tier 2 site-specific NMOC concentration is equal to or greater than 34 megagrams per year, the owner or operator m ust either: (A) Submit a gas collection and control system desi gn plan as specified in § 60.38f(d) within 1 year and insta ll and operate a gas collection and control system accordi ng to § 60.33f(b) and (c) within 30 months; (B) Determine a site-specific methane generation ra te

constant and recalculate the NMOC emission rate usi ng the sitespecific methane generation rate using the Tier 3 p rocedures specified in paragraph (a)(4) of this section; or (C) Conduct a surface emission monitoring demonstra tion using the Tier 4 procedures specified in paragraph (a)(6) of

this section. (4) Tier 3. The site-specific methane generation ra te constant must be determined using the procedures pr ovided in Method 2E of appendix A of this part. The landfill owner or operator must estimate the NMOC mass emission rate using the equations in paragraph (a)(1)(i) or (a)(1)(ii) of t his section and using a site-specific methane generation rate c onstant, and the site-specific NMOC concentration as determined in paragraph (a)(3) of this section instead of the default value s provided in paragraph (a)(1) of this section. The landfill owne r or operator***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 268 of 324 must compare the resulting NMOC mass emission rate to the standard of 34 megagrams per year. (i) If the NMOC mass emission rate as calculated us ing the Tier 2 site-specific NMOC concentration and Tier 3 site-specific methane generation rate is equal to or greater than 34 megagrams per year, the owner or operator must either: (A) Submit a gas collection and control system desi gn plan as specified in § 60.38f(d) within 1 year and insta ll and operate a gas collection and control system accordi ng to § 60.33f(b) and (c) within 30 months; or (B) Conduct a surface emission monitoring demonstra tion using the Tier 4 procedures specified in paragraph (a)(6) of

this section. (ii) If the NMOC mass emission rate is less than 34 megagrams per year, then the owner or operator must recalculate the NMOC mass emission rate annually using the equa tions in paragraph (a)(1) of this section and using the site -specific Tier 2 NMOC concentration and Tier 3 methane genera tion rate constant and submit a periodic emission rate report as provided in § 60.38f(c). The calculation of the methane gene ration rate constant is performed only once, and the value obta ined from this test must be used in all subsequent annual NMO C emission

rate calculations.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 269 of 324 (5) The owner or operator may use other methods to determine the NMOC concentration or a site-specific methane generation rate constant as an alternative to the m ethods required in paragraphs (a)(3) and (a)(4) of this se ction if the method has been approved by the Administrator. (6) Tier 4. The landfill owner or operator may demo nstrate that surface methane emissions are below 500 parts per million by conducting surface emission monitoring on a quar terly basis using the following procedures. (i) The owner or operator must measure surface concentrations of methane along the entire perimete r of the landfill and along a pattern that traverses the lan dfill at no more than 30-meter intervals using an organic vapor analyzer, flame ionization detector, or other portable monito r meeting the specifications provided in paragraph (a)(6)(iv) of this section. (ii) The background concentration must be determine d by moving the probe inlet upwind and downwind at least 30 meters from the waste mass boundary of the landfill. (iii) Surface emission monitoring must be performedin accordance with section 8.3.1 of Method 21 of appen dix A of this part, except that the probe inlet must be placed wi thin 5 to 10 centimeters of the landfill surface. Monitoring mus t be performed during typical meteorological conditions.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 270 of 324 (A) Surface emission monitoring must be terminated when the average wind speed exceeds 5 miles per hour or the instantaneous wind speed exceeds 10 miles per hour. The Administr ator may approve alternatives to this wind speed surface mon itoring termination for landfills consistently having measu red winds in excess of these specified limits. Average wind spee d must be determined on a 15-minute average using an onsite a nemometer with a continuous recorder for the entire duration of the monitoring event. (B) Landfill surface areas where visual observation s indicate elevated concentrations of landfill gas, s uch as distressed vegetation and cracks or seeps in the co ver, and all cover penetrations must also be monitored using a d evice meeting the specifications provided in paragraph (a)(6)(iv) of this

section. (iv) Each owner or operator seeking to comply with the provisions in paragraph (a)(6) of this section must comply with the following instrumentation specifications and pr ocedures for surface emission monitoring devices. (A) The portable analyzer must meet the instrument specifications provided in section 3 of Method 21 o f appendix A of this part, except that “methane” replaces all re ferences to

“VOC”.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 271 of 324 (B) The calibration gas is methane, diluted to a no minal concentration of 500 parts per million in air. (C) To meet the performance evaluation requirements in section 3.1.3 of Method 21 of appendix A of this pa rt, the instrument evaluation procedures of section 4.4 of Method 21 of appendix A of this part must be used. (D) The calibration procedures provided in section 4.2 of Method 21 of appendix A of this part must be follow ed immediately before commencing a surface monitoring survey. (v) Each owner or operator seeking to comply with t he Tier 4 provisions in paragraph (a)(6) of this section mu st maintain records of surface emission monitoring as provided in § 60.39f(g) and submit a Tier 4 surface emissions rep ort as provided in § 60.38f(c)(5)(iii). (vi) If there is any measured concentration of meth ane of 500 parts per million or greater from the surface o f the landfill, the owner or operator must submit a gas c ollection and control system design plan within 1 year of the fir st measured concentration of methane of 500 parts per million o r greater from the surface of the landfill according to § 60. 38f(d) and install and operate a gas collection and control sy stem according to § 60.33f(b) and (c) within 30 months o f the first measured concentration of methane of 500 parts per million or greater from the surface of the landfill.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 272 of 324 (vii) If after four consecutive quarterly monitorin g periods there is no measured concentration of metha ne of 500 parts per million or greater from the surface of th e landfill, the owner or operator must either conduct semi-annu al surface emission monitoring using the methods specified in this section or recalculate the NMOC mass emission rate annually as provided in § 60.33f(e). (A) If conducting semi-annual surface emissions mon itoring and there is any measured concentration of methane of 500 parts per million or greater from the surface of the land fill, the owner or operator must submit a gas collection and control system design plan within 1 year of the first measu red concentration of methane of 500 parts per million o r greater from the surface of the landfill according to § 60. 38f(d) and install and operate a gas collection and control sy stem according to § 60.33f(b) and (c) within 30 months o f the first measured concentration of methane of 500 parts per million or greater from the surface of the landfill. (B) [Reserved] (b) After the installation and startup of a collect ion and control system in compliance with this subpart, the owner or operator must calculate the NMOC emission rate for purposes of determining when the system can be capped or remove d as provided in § 60.33f(f), using the following equation:***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 273 of 324 MNMOC = 1.89 × 10−3Q LFG C NMOC

Where:

MNMOC = Mass emission rate of NMOC, megagrams per year. Q LFG = Flow rate of landfill gas, cubic meters per minu te. C NMOC = NMOC concentration, parts per million by volume as

hexane. (1) The flow rate of landfill gas, Q LFG , must be determined by measuring the total landfill gas flow rate at th e common header pipe that leads to the control system using a gas flow measuring device calibrated according to the provis ions of section 4 of Method 2E of appendix A of this part. (2) The average NMOC concentration, C NMOC , must be determined by collecting and analyzing landfill gas sampled from the common header pipe before the gas moving or con densate removal equipment using the procedures in Method 25 or Method 25C of appendix A of this part. The sample location on the common header pipe must be before any condensate re moval or other gas refining units. The landfill owner or ope rator must

divide the NMOC concentration from Method 25 or Met hod 25C of appendix A of this part by six to convert from CNMO C as carbon

to C NMOC as hexane. (3) The owner or operator may use another method to determine landfill gas flow rate and NMOC concentra tion if the method has been approved by the Administrator.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 274 of 324 (i) Within 60 days after the date of calculating th e NMOC emission rate for purposes of determining when the system can be capped or removed, the owner operator must submit t he results according to § 60.38f(j). (ii) [Reserved] (c) When calculating emissions for Prevention of Significant Deterioration (PSD) purposes, the owner or operator of each MSW landfill subject to the provisions of t his subpart must estimate the NMOC emission rate for comparison to the PSD major source and significance levels in §§51.166 or 52.21 of this chapter using Compilation of Air Pollutant Emi ssion Factors, Volume I: Stationary Point and Area Source s (AP–42) or other approved measurement procedures. (d) For the performance test required in § 60.33f(c )(1), the net heating value of the combusted landfill gas as determined in § 60.18(f)(3) is calculated from the concentration of methane in the landfill gas as measured by Metho d 3C. A minimum of three 30-minute Method 3C samples are de termined. The measurement of other organic components, hydrogen, and carbon monoxide is not applicable. Method 3C may be used t o determine the landfill gas molecular weight for calculating t he flare gas exit velocity under § 60.18(f)(4). (1) Within 60 days after the date of completing eac h performance test (as defined in § 60.8), the owner or operator***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 275 of 324 must submit the results of the performance tests re quired by § 60.35f(b) or (d), including any associated fuel ana lyses, according to § 60.38f(j). (2) [Reserved] (e) For the performance test required in § 60.33f(c )(2), Method 25 or 25C (Method 25C may be used at the inl et only) of appendix A of this part must be used to determine c ompliance with the 98 weight-percent efficiency or the 20 par ts per million by volume outlet NMOC concentration level, unless another method to demonstrate compliance has been a pproved by the Administrator as provided by § 60.38f(d). Metho d 3 or 3A must be used to determine oxygen for correcting the NMOC concentration as hexane to 3 percent. In cases wher e the outlet concentration is less than 50 ppm NMOC as carbon (8 ppm NMOC as hexane), Method 25A should be used in place of Meth od 25. The following equation must be used to calculate effici ency: Control Efficiency = (NMOCin − NMOCout)/(NMOCin)

Where:

NMOCin = Mass of NMOC entering control device. NMOCout = Mass of NMOC exiting control device. (1) Within 60 days after the date of completing eac h performance test (as defined in § 60.8), the owner or operator must submit the results of the performance tests, i ncluding any associated fuel analyses, according to § 60.38f(j).***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 276 of 324 (2) [Reserved] § 60.36f Compliance provisions. For approval, a State plan must include the complia nce provisions in this section. (a) Except as provided in § 60.38f(d)(2), the speci fied methods in paragraphs (a)(1) through (6) of this se ction must be used to determine whether the gas collection system is in compliance with § 60.33f(b)(2). (1) For the purposes of calculating the maximum exp ected gas generation flow rate from the landfill to deter mine compliance with § 60.33f(b)(2)(i), one of the follo wing equations must be used. The k and Lo kinetic factor s should be those published in the most recent AP–42 or other s ite-specific values demonstrated to be appropriate and approved by the Administrator. If k has been determined as specifie d in § 60.35f(a)(4), the value of k determined from the te st must be used. A value of no more than 15 years must be used for the intended use period of the gas mover equipment. The active life of the landfill is the age of the landfill plus the estimated number of years until closure. (i) For sites with unknown year-to-year solid waste acceptance rate: Qm = 2LoR (e −kc−e−kt)

Where:***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 277 of 324 Qm = Maximum expected gas generation flow rate, cub ic

meters per year. Lo = Methane generation potential, cubic meters per

megagram solid waste. R = Average annual acceptance rate, megagrams per y ear. k = Methane generation rate constant, year−1. t = Age of the landfill at equipment installation plus

the time the owner or operator intends to use the gas mover equipment or active life of the landfill, whichever is less. If the equipment is installed after closure, t is the age of the landfill at installation, years. c = Time since closure, years (for an active landf ill c

= 0 and e−kc = 1). (ii) For sites with known year-to-year solid waste acceptance rate:

 ∑ 2  (    )   Where:

QM = Maximum expected gas generation flow rate, cub ic

meters per year. k = Methane generation rate constant, year−1. Lo = Methane generation potential, cubic meters per

megagram solid waste. Mi = Mass of solid waste in the ith section, megagr ams. ti = Age of the ith section, years. (iii) If a collection and control system has been installed, actual flow data may be used to project the maximum expected gas generation flow rate instead of, or in conjunction with, the equations in paragraphs (a)(1)(i) and (ii ) of this section. If the landfill is still accepting waste, the actual***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 278 of 324 measured flow data will not equal the maximum expec ted gas generation rate, so calculations using the equation s in paragraphs (a)(1)(i) or (ii) of this section or oth er methods must be used to predict the maximum expected gas ge neration rate over the intended period of use of the gas control system equipment. (2) For the purposes of determining sufficient dens ity of gas collectors for compliance with § 60.33f(b)(2)(i i), the owner or operator must design a system of vertical wells, horizontal collectors, or other collection devices, satisfacto ry to the Administrator, capable of controlling and extractin g gas from all portions of the landfill sufficient to meet all operational and performance standards. (3) For the purpose of demonstrating whether the ga s collection system flow rate is sufficient to determ ine compliance with § 60.33f(b)(2)(iii), the owner or o perator must measure gauge pressure in the gas collection header applied to each individual well monthly. If a positive pressur e exists,

action must be initiated to correct the exceedance within 5 calendar days, except for the three conditions allo wed under § 60.34f(b). If negative pressure cannot be achieved without excess air infiltration within 15 calendar days of the first measurement, the gas collection system must be expa nded to correct the exceedance within 120 days of the initi al***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 279 of 324 measurement of positive pressure. Any attempted cor rective measure must not cause exceedances of other operati onal or performance standards. An alternative timeline for correcting the exceedance may be submitted to the Administrato r for approval. (4) Owners or operators are not required to expand the system as required in paragraph (a)(3) of this sect ion during the first 180 days after gas collection system star tup. (5) [Reserved] (6) An owner or operator seeking to demonstrate compliance with § 60.33f(b)(2)(iv) through the use of a collec tion system not conforming to the specifications provided in § 60.40f must provide information satisfactory to the Administrat or as specified in § 60.38f(d)(3) demonstrating that offs ite migration is being controlled. (b) For purposes of compliance with § 60.34f(a), ea ch owner or operator of a controlled landfill must place eac h well or design component as specified in the approved desig n plan as provided in § 60.38f(d). Each well must be installe d no later than 60 days after the date on which the initial so lid waste has been in place for a period of: (1) 5 years or more if active; or (2) 2 years or more if closed or at final grade.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 280 of 324 (c) The following procedures must be used for compl iance with the surface methane operational standard as pr ovided in § 60.34f(d): (1) After installation and startup of the gas colle ction system, the owner or operator must monitor surface concentrations of methane along the entire perimete r of the collection area and along a pattern that traverses the landfill at no more than 30-meter intervals (or a site-speci fic established spacing) for each collection area on a quarterly basis using an organic vapor analyzer, flame ioniza tion detector, or other portable monitor meeting the spe cifications provided in § 60.36f(d). (2) The background concentration must be determinedby moving the probe inlet upwind and downwind outside the boundary

of the landfill at a distance of at least 30 meters from the perimeter wells. (3) Surface emission monitoring must be performed i n accordance with section 8.3.1 of Method 21 of appen dix A of this part, except that the probe inlet must be placed wi thin 5 to 10 centimeters of the ground. Monitoring must be perfo rmed during typical meteorological conditions. (4) Any reading of 500 parts per million or more ab ove background at any location must be recorded as a mo nitored exceedance and the actions specified in paragraphs (c)(4)(i)***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 281 of 324 through (v) of this section must be taken. As long as the specified actions are taken, the exceedance is not a violation of the operational requirements of § 60.34f(d). (i) The location of each monitored exceedance must be

marked and the location and concentration recorded. For location, you must determine the latitude and longi tude coordinates using an instrument with an accuracy of at least 3 meters. Your coordinates must be in decimal degrees with at least five decimal places. (ii) Cover maintenance or adjustments to the vacuum of the adjacent wells to increase the gas collection in th e vicinity of

each exceedance must be made and the location must be remonitored within 10 calendar days of detecting the exceedance. (iii) If the re-monitoring of the location shows a second exceedance, additional corrective action must be ta ken and the location must be monitored again within 10 days of the second exceedance. If the re-monitoring shows a third exce edance for the same location, the action specified in paragrap h (c)(4)(v) of this section must be taken, and no further monit oring of that location is required until the action specified in paragraph (c)(4)(v) of this section has been taken. (iv) Any location that initially showed an exceedan ce but has a methane concentration less than 500 parts per million methane above background at the 10-day re-monitorin g specified***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 282 of 324 in paragraph (c)(4)(ii) or (iii) of this section mu st be remonitored 1 month from the initial exceedance. If t he 1-month re-monitoring shows a concentration less than 500 p arts per million above background, no further monitoring of that location is required until the next quarterly monitoring per iod. If the 1-month re-monitoring shows an exceedance, the acti ons specified in paragraph (c)(4) (iii) or (v) of this section mu st be taken. (v) For any location where monitored methane concen tration equals or exceeds 500 parts per million above backg round three times within a quarterly period, a new well or othe r collection device must be installed within 120 calendar days o f the initial exceedance. An alternative remedy to the exceedance , such as upgrading the blower, header pipes or control devic e, and a corresponding timeline for installation may be subm itted to the Administrator for approval. (5) The owner or operator must implement a program to monitor for cover integrity and implement cover rep airs as necessary on a monthly basis. (d) Each owner or operator seeking to comply with t he provisions in paragraph (c) of this section must co mply with the following instrumentation specifications and proced ures for surface emission monitoring devices: (1) The portable analyzer must meet the instrument specifications provided in section 3 of Method 21 o f appendix A***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 283 of 324 of this part, except that “methane” must replace al l references

to “VOC”. (2) The calibration gas must be methane, diluted to a nominal concentration of 500 parts per million in a ir. (3) To meet the performance evaluation requirements in section 3.1.3 of Method 21 of appendix A of this pa rt, the instrument evaluation procedures of section 4.4 of Method 21 of appendix A of this part must be used. (4) The calibration procedures provided in section 4.2 of Method 21 of appendix A of this part must be follow ed immediately before commencing a surface monitoring survey. (e) The provisions of this subpart apply at all tim es, including periods of startup, shutdown or malfuncti on. § 60.37f Monitoring of operations. For approval, a State plan must include the monitor ing provisions in this section, except as provided in § 60.38f(d)(2). (a) Each owner or operator seeking to comply with § 60.33f(b)(2) for an active gas collection system mu st install a sampling port and a thermometer, other temperature measuring device, or an access port for temperature measureme nts at each

wellhead and: (1) Measure the gauge pressure in the gas collectio n header on a monthly basis as provided in § 60.36f(a)(3); a nd***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 284 of 324 (2) Monitor nitrogen or oxygen concentration in the landfill gas on a monthly basis as follows: (i) The nitrogen level must be determined using Met hod 3C,

unless an alternative test method is established as allowed by § 60.38f(d)(2). (ii) Unless an alternative test method is establish ed as allowed by § 60.38f(d)(2), the oxygen must be deter mined by an oxygen meter using Method 3A or 3C except that: (A) The span must be set between 10 and 12 percent oxygen; (B) A data recorder is not required; (C) Only two calibration gases are required, a zero and

span; (D) A calibration error check is not required; (E) The allowable sample bias, zero drift, and cali bration drift are ±10 percent. (3) Monitor temperature of the landfill gas on a mo nthly basis. The temperature measuring device must be cal ibrated annually using the procedure in 40 CFR part 60, App endix A-1, Method 2, Section 10.3. (b) Each owner or operator seeking to comply with § 60.33f(c) using an enclosed combustor must calibrat e, maintain, and operate according to the manufacturer's specifi cations, the following equipment:***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 285 of 324 (1) A temperature monitoring device equipped with a continuous recorder and having a minimum accuracy o f ±1 percent of the temperature being measured expressed in degr ees Celsius or ±0.5 degrees Celsius, whichever is greater. A te mperature monitoring device is not required for boilers or pr ocess heaters with design heat input capacity equal to or greater than 44 megawatts. (2) A device that records flow to or bypass of the control device. The owner or operator must: (i) Install, calibrate, and maintain a gas flow rat e measuring device that must record the flow to the c ontrol device at least every 15 minutes; and (ii) Secure the bypass line valve in the closed pos ition with a car-seal or a lock-and-key type configuratio n. A visual inspection of the seal or closure mechanism must be performed at least once every month to ensure that the valve is maintained in the closed position and that the gas flow is not di verted through the bypass line. (c) Each owner or operator seeking to comply with § 60.33f(c) using a non-enclosed flare must install, calibrate, maintain, and operate according to the manufacturer 's specifications the following equipment:***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 286 of 324 (1) A heat sensing device, such as an ultraviolet b eam sensor or thermocouple, at the pilot light or the f lame itself to indicate the continuous presence of a flame. (2) A device that records flow to or bypass of the flare. The owner or operator must: (i) Install, calibrate, and maintain a gas flow rat e measuring device that must record the flow to the c ontrol device at least every 15 minutes; and (ii) Secure the bypass line valve in the closed pos ition with a car-seal or a lock-and-key type configuratio n. A visual inspection of the seal or closure mechanism must be performed at least once every month to ensure that the valve is maintained in the closed position and that the gas flow is not di verted through the bypass line. (d) Each owner or operator seeking to demonstrate compliance with § 60.33f(c) using a device other th an a nonenclosed flare or an enclosed combustor or a treatm ent system must provide information satisfactory to the Admini strator as provided in § 60.38f(d)(2) describing the operation of the control device, the operating parameters that wouldindicate proper performance, and appropriate monitoring proc edures. The

Administrator must review the information and eithe r approve it, or request that additional information be submitted . The***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 287 of 324 Administrator may specify additional appropriate mo nitoring procedures. (e) Each owner or operator seeking to install a col lection system that does not meet the specifications in § 6 0.40f or seeking to monitor alternative parameters to those required by § 60.34f through § 60.37f must provide information sa tisfactory to the Administrator as provided in § 60.38f(d)(2) and(3) describing the design and operation of the collecti on system, the operating parameters that would indicate proper performance, and appropriate monitoring procedures. The Administ rator may specify additional appropriate monitoring procedure s. (f) Each owner or operator seeking to demonstrate compliance with the 500 parts per million surface m ethane operational standard in § 60.34f(d) must monitor su rface concentrations of methane according to the procedur es provided in § 60.36f(c) and the instrument specifications in § 60.36f(d). Any closed landfill that has no monitored exceedanc es of the operational standard in three consecutive quarterly monitoring periods may skip to annual monitoring. Any methane reading of 500 parts per million or more above background dete cted during the annual monitoring returns the frequency for tha t landfill to quarterly monitoring. (g) Each owner or operator seeking to demonstrate compliance with the control system requirements in § 60.33f(c)***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 288 of 324 using a landfill gas treatment system must calibrat e, maintain, and operate according to the manufacturer’s specifi cations a device that records flow to or bypass of the treatm ent system. The owner or operator must: (1) Install, calibrate, and maintain a gas flow rat e measuring device that records the flow to the treat ment system at least every 15 minutes; and (2) Secure the bypass line valve in the closed posi tion with a car-seal or a lock-and-key type configuratio n. A visual inspection of the seal or closure mechanism must be performed at least once every month to ensure that the valve is maintained in the closed position and that the gas flow is not di verted through the bypass line. § 60.38f Reporting guidelines. For approval, a State plan must include the reporti ng provisions listed in this section, as applicable, e xcept as provided under §§ 60.24 and 60.38f(d)(2). (a) Design capacity report. For existing MSW landfi lls subject to this subpart, the initial design capacit y report must be submitted no later than 90 days after the effect ive date of EPA approval of the State’s plan under section 111( d) of the Clean Air Act. The initial design capacity report m ust contain the following information:***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 289 of 324 (1) A map or plot of the landfill, providing the si ze and location of the landfill, and identifying all areas where solid waste may be landfilled according to the permit iss ued by the state, local, or tribal agency responsible for regu lating the

landfill. (2) The maximum design capacity of the landfill. Wh ere the maximum design capacity is specified in the permit issued by the state, local, or tribal agency responsible for regu lating the landfill, a copy of the permit specifying the maxim um design capacity may be submitted as part of the report. If the maximum design capacity of the landfill is not specified in the permit, the maximum design capacity must be calculated usin g good engineering practices. The calculations must be pro vided, along with the relevant parameters as part of the report. The landfill may calculate design capacity in either megagrams o r cubic meters for comparison with the exemption values. If the owner or operator chooses to convert the design capacity fro m volume to

mass or from mass to volume to demonstrate its desi gn capacity is less than 2.5 million megagrams or 2.5 million c ubic meters, the calculation must include a site-specific densit y, which must be recalculated annually. Any density conversions m ust be documented and submitted with the design capacity r eport. The state, local, or tribal agency or the Administrator may request***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 290 of 324 other reasonable information as may be necessary to verify the maximum design capacity of the landfill. (b) Amended design capacity report. An amended desi gn capacity report must be submitted providing notific ation of an increase in the design capacity of the landfill, wi thin 90 days of an increase in the maximum design capacity of th e landfill to or above 2.5 million megagrams and 2.5 million cubi c meters. This increase in design capacity may result from an increase in the permitted volume of the landfill or an increase in the density as documented in the annual recalculation r equired in § 60.39f(f). (c) NMOC emission rate report. For existing MSW lan dfills covered by this subpart with a design capacity equa l to or greater than 2.5 million megagrams and 2.5 million cubic meters, the NMOC emission rate report must be submitted fol lowing the procedure specified in paragraph (j) of this sectio n no later than 90 days after the effective date of EPA approv al of the State’s plan under section 111(d) of the Clean Air Act. The NMOC emission rate report must be submitted annually fol lowing the procedure specified in paragraph (j) of this sectio n, except as provided for in paragraph (c)(3) of this section. T he Administrator may request such additional informati on as may be necessary to verify the reported NMOC emission rate

.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 291 of 324 (1) The NMOC emission rate report must contain an a nnual or 5-year estimate of the NMOC emission rate calculate d using the formula and procedures provided in § 60.35f(a). (2) The NMOC emission rate report must include all the data, calculations, sample reports and measurements used to estimate the annual or 5-year emissions. (3) If the estimated NMOC emission rate as reportedin the annual report to the Administrator is less than 34 megagrams per year in each of the next 5 consecutive years, the o wner or operator may elect to submit, following the procedu re specified in paragraph (j) of this section, an estimate of th e NMOC emission rate for the next 5-year period in lieu of the annual report. This estimate must include the current amou nt of solid waste-in-place and the estimated waste acceptance r ate for each year of the 5 years for which an NMOC emission rate is estimated. All data and calculations upon which thi s estimate is based must be provided to the Administrator. This e stimate must be revised at least once every 5 years. If the actu al waste acceptance rate exceeds the estimated waste accepta nce rate in any year reported in the 5-year estimate, a revised5-year

estimate must be submitted to the Administrator. Th e revised estimate must cover the 5-year period beginning wit h the year in which the actual waste acceptance rate exceeded the estimated waste acceptance rate.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 292 of 324 (4) Each owner or operator subject to the requireme nts of this subpart is exempted from the requirements to s ubmit an NMOC emission rate report, after installing a collection and control system that complies with § 60.33f(b) and (c), duri ng such time as the collection and control system is in operatio n and in compliance with §§ 60.34f and 60.36f. (5) Each owner or operator of an MSW landfill havin g a design capacity equal to or greater than 2.5 millio n megagrams and 2.5 million cubic meters must submit a collecti on and control system design plan to the Administrator wit hin 1 year of the first NMOC emission rate report in which the NM OC emission rate equals or exceeds 34 megagrams per year, excep t as follows: (i) If the owner or operator elects to recalculate the NMOC emission rate after Tier 2 NMOC sampling and analys is as provided in § 60.35f(a)(3) and the resulting rate i s less than 34 megagrams per year, annual periodic reporting mu st be resumed, using the Tier 2 determined site-specific NMOC concentration, until the calculated emission rate i s equal to or greater than 34 megagrams per year or the landfill is closed. The revised NMOC emission rate report, with the rec alculated emission rate based on NMOC sampling and analysis, must be submitted, following the procedure specified in par agraph (j) of this section, within 180 days of the first calculat ed exceedance of 34 megagrams per year.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 293 of 324 (ii) If the owner or operator elects to recalculate the NMOC emission rate after determining a site-specifi c methane generation rate constant k, as provided in Tier 3 i n § 60.35f(a)(4), and the resulting NMOC emission rate is less than 34 megagrams per year, annual periodic reporting mu st be resumed. The resulting site-specific methane genera tion rate

constant k must be used in the emission rate calcul ation until

such time as the emissions rate calculation results in an exceedance. The revised NMOC emission rate report b ased on the provisions of § 60.35f(a)(4) and the resulting site -specific methane generation rate constant k must be submitte d, following the procedure specified in paragraph (j) of this se ction, to the Administrator within 1 year of the first calculatedNMOC emission rate equaling or exceeding 34 megagrams pe r year. (iii) If the owner or operator elects to demonstrat e that site-specific surface methane emissions are below 5 00 parts per million methane, then the owner or operator must su bmit annually a Tier 4 surface emissions report as specified in t his paragraph following the procedure specified in paragraph (j) of this section. If the Tier 4 surface emissions report sho ws no surface emissions readings of 500 parts per million methane or greater for four consecutive quarters, then the landfill ma y continue Tier 4 monitoring at a reduced semi-annual frequenc y or return to Tier 1, 2, or 3. An owner or operator may elect to***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 294 of 324 recalculate NMOC using Tier 1, 2, or 3 only if it h as four consecutive quarters with no surface emissions moni toring readings of 500 parts per million or greater. The N MOC emission rate report must be submitted annually, following t he procedure specified in paragraph (j) of this section, except as provided for in paragraph (c)(3) of this section. The Admini strator may request such additional information as may be neces sary to verify the reported instantaneous surface emission readings. The Tier 4 surface emissions report must clearly identi fy the location, date, and reading (in parts per million) of any value 500 parts per million methane or greater, other tha n nonrepeatable, momentary readings. For location, you m ust determine the latitude and longitude coordinates using an ins trument with an accuracy of at least 3 meters. Your coordinates must be in decimal degrees with at least five decimal places. (iv) If the landfill is in the closed landfill subc ategory, the owner or operator must submit a collection and control system design plan to the Administrator within 1 ye ar of the first NMOC emission rate report in which the NMOC e mission rate equals or exceeds 50 megagrams per year, except as follows: (A) If the owner or operator elects to recalculate the NMOC emission rate after Tier 2 NMOC sampling and analys is as provided in § 60.35f(a)(3) and the resulting rate i s less than 50 megagrams per year, annual periodic reporting mu st be***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 295 of 324 resumed, using the Tier 2 determined site-specific NMOC concentration, until the calculated emission rate i s equal to or greater than 50 megagrams per year or the landfill is closed. The revised NMOC emission rate report, with the rec alculated emission rate based on NMOC sampling and analysis, must be submitted, following the procedure specified in par agraph (j) of this section, within 180 days of the first calculat ed exceedance of 50 megagrams per year. (B) If the owner or operator elects to recalculate the NMOC emission rate after determining a site-specific met hane generation rate constant k, as provided in Tier 3 i n § 60.35f(a)(4), and the resulting NMOC emission rate is less than 50 megagrams per year, annual periodic reporting mu st be resumed. The resulting site-specific methane genera tion rate

constant k must be used in the emission rate calcul ation until

such time as the emissions rate calculation results in an exceedance. The revised NMOC emission rate report b ased on the provisions of § 60.35f(a)(4) and the resulting site -specific methane generation rate constant k must be submitte d, following the procedure specified in paragraph (j) of this se ction, to the Administrator within 1 year of the first calculatedNMOC emission rate equaling or exceeding 50 megagrams pe r year.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 296 of 324 (C) The landfill owner or operator elects to demons trate surface emissions are low, consistent with the prov isions in § 60.38(c)(5)(iii). (D) The landfill has already submitted a gas collec tion and control system design plan consistent with the prov isions of 40 CFR part 60, subpart WWW; 40 CFR part 62, subpart G GG; or a state plan implementing 40 CFR part 60, subpart Cc. (d) Collection and control system design plan. The State plan must include a process for state review and ap proval of the site-specific design plan for each gas collection a nd control system. The collection and control system design pl an must meet the following requirements: (1) The collection and control system as described in the design plan must meet the design requirements in § 60.33f(b) and (c). (2) The collection and control system design plan m ust include any alternatives to the operational standar ds, test methods, procedures, compliance measures, monitorin g, recordkeeping, or reporting provisions of §§ 60.34f through 60.39f proposed by the owner or operator. (3) The collection and control system design plan m ust either conform to specifications for active collect ion systems in § 60.40f or include a demonstration to the Admin istrator's***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 297 of 324 satisfaction of the sufficiency of the alternative provisions to § 60.40f. (4) If the owner or operator chooses to demonstrate compliance with the emission control requirements o f this subpart using a treatment system as defined in this subpart, then the owner or operator must prepare a site-spec ific treatment system monitoring plan as specified in § 60.39f(b)(5)(ii). (5) The Administrator must review the information s ubmitted under paragraphs (d)(1) through (4) of this section and either approve it, disapprove it, or request that addition al information be submitted. Because of the many site- specific factors involved with landfill gas system design, a lternative systems may be necessary. A wide variety of system designs are possible, such as vertical wells, combination horiz ontal and vertical collection systems, or horizontal trenches only, leachate collection components, and passive systems

. (e) Revised design plan. The owner or operator who has already been required to submit a design plan under paragraph (d) of this section, or under 40 CFR part 60, subpa rt WWW; 40 CFR part 62, subpart GGG; or a state plan implement ing 40 CFR part 60, subpart Cc, must submit a revised design p lan to the Administrator for approval as follows:***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 298 of 324 (1) Within 90 days of expanding operations to an ar ea not covered by the previously approved design plan. (2) Prior to installing or expanding the gas collec tion system in a way that is not consistent with the des ign plan that was submitted to the Administrator according to par agraph (d) of

this section. (f) Closure report. Each owner or operator of a con trolled landfill must submit a closure report to the Admini strator within 30 days of ceasing waste acceptance. The Adm inistrator may request additional information as may be necess ary to verify that permanent closure has taken place in accordanc e with the requirements of 40 CFR 258.60. If a closure report has been submitted to the Administrator, no additional waste s may be placed into the landfill without filing a notificat ion of modification as described under § 60.7(a)(4). (g) Equipment removal report. Each owner or operato r of a controlled landfill must submit an equipment remova l report to the Administrator 30 days prior to removal or cessa tion of operation of the control equipment. (1) The equipment removal report must contain the f ollowing

items: (i) A copy of the closure report submitted in accor dance with paragraph (f) of this section; and***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 299 of 324 (ii) A copy of the initial performance test report demonstrating that the 15-year minimum control peri od has expired, unless the report of the results of the pe rformance

test has been submitted to the EPA via the EPA’s CD X, or information that demonstrates that the GCCS will be unable to operate for 15 years due to declining gas flows. In the equipment removal report, the process unit(s) teste d, the pollutant(s) tested, and the date that such perform ance test was conducted may be submitted in lieu of the performan ce test report if the report has been previously submitted to the EPA’s CDX; and (iii) Dated records of surface emissions monitoring data of

the landfill or closed area that demonstrates that there are no surface emissions of 500 parts per million or great er for four consecutive quarters, unless the reports have been submitted to

the EPA via the EPA’s CDX. If the surface emissions monitoring reports have been previously submitted to the EPA’s CDX, a statement that the reports have been submitted elec tronically and the dates that the reports were submitted to th e EPA’s CDX may be submitted in the equipment removal report in lieu of the surface emissions monitoring reports; or (iv) Dated copies of three successive NMOC emission rate reports demonstrating that the landfill is no longe r producing 34 megagrams or greater of NMOC per year; or***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 300 of 324 (v) For the closed landfill subcategory, dated copi es of three successive NMOC emission rate reports demonst rating that the landfill is no longer producing 50 megagrams or greater of NMOC per year. (2) The Administrator may request such additional information as may be necessary to verify that all of the conditions for removal in § 60.33f(f) have been met

. (h) Annual report. The owner or operator of a landf ill seeking to comply with § 60.33f(e)(2) using an acti ve collection system designed in accordance with § 60.33f(b) must submit to the Administrator, following the procedures specifi ed in paragraph (j) of this section, an annual report of the recorded information in paragraphs (h)(1) through (h)(6) of this section. The initial annual report must be submitted within 180 days of installation and startup of the collection and cont rol system. The initial annual report must include the followin g information pertaining to the initial performance test report r equired under § 60.8: The process unit(s) tested, the pollutant(s ) tested, and the date that such performance test was conducted. The initial performance test report must be submitted, followin g the procedure specified in § 60.8(j), no later than the date that the initial annual report is submitted. For enclose d combustion devices, flares, and treatment systems reportable e xceedances are defined under § 60.39f(c)(1).***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 301 of 324 (1) Value and length of time for exceedance of appl icable parameters monitored under § 60.37f(a)(1), (b), (c) , (d), and (g). (2) Description and duration of all periods when th e gas stream is diverted from the control device or treat ment system through a bypass line or the indication of bypass f low as specified under § 60.37f. (3) Description and duration of all periods when th e control device or treatment system was not operatin g and length of time the control device or treatment system was not operating. (4) All periods when the collection system was not operating. (5) The location of each exceedance of the 500 part s per million methane concentration as provided in § 60.3 4f(d) and the

concentration recorded at each location for which a n exceedance was recorded in the previous month. For location, y ou must determine the latitude and longitude coordinates us ing an instrument with an accuracy of at least 3 meters. Y our coordinates must be in decimal degrees with at leas t five decimal places. (6) The date of installation and the location of ea ch well or collection system expansion added pursuant to § 60.36f(a)(3), (b), and (c)(4).***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 302 of 324 (i) Initial performance test report. Each owner or operator seeking to comply with § 60.33f(c) must include the following information with the initial performance test repor t required under § 60.8: (1) A diagram of the collection system showing coll ection system positioning including all wells, horizontal collectors, surface collectors, or other gas extraction devices , including the locations of any areas excluded from collection and the proposed sites for the future collection system exp ansion; (2) The data upon which the sufficient density of w ells, horizontal collectors, surface collectors, or other gas extraction devices and the gas mover equipment sizi ng are based; (3) The documentation of the presence of asbestos o r nondegradable material for each area from which col lection wells have been excluded based on the presence of asbesto s or nondegradable material; (4) The sum of the gas generation flow rates for al l areas

from which collection wells have been excluded base d on nonproductivity and the calculations of gas generat ion flow rate for each excluded area; (5) The provisions for increasing gas mover equipme nt capacity with increased gas generation flow rate, i f the present gas mover equipment is inadequate to move the maxim um flow rate expected over the life of the landfill; and***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 303 of 324 (6) The provisions for the control of offsite migra tion. (j) Electronic reporting. The owner or operator mus t submit the results of each performance test according to t he following procedures: (1) For data collected using test methods supportedby the EPA’s Electronic Reporting Tool (ERT) as listed on the EPA’s ERT Web site (http://www.epa.gov/ttn/chief/ert/index.ht ml), you must submit the results of the performance test to the E PA via the Compliance and Emissions Data Reporting Interface ( CEDRI). CEDRI can be accessed through the EPA’s Central Data Exch ange (CDX) (http://cdx.epa.gov/epa_home.asp). Performance test data must be submitted in a file format generated through the us e of the EPA’s ERT. Alternatively, you may submit performanc e test data

in an electronic file format consistent with the ex tensible markup language (XML) schema listed on the EPA’s ER T Web site, once the XML schema is available. If you claim that some of the performance test information being submitted is con fidential business information (CBI), you must submit a compl ete file generated through the use of the EPA’s ERT or an al ternate electronic file consistent with the XML schema list ed on the EPA’s ERT Web site, including information claimed t o be CBI, on a compact disc, flash drive, or other commonly usedelectronic storage media to the EPA. The electronic media must be clearly marked as CBI and mailed to U.S. EPA/OAPQS/CORE CBI Office,***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 304 of 324 Attention: Group Leader, Measurement Policy Group, MD C404-02, 4930 Old Page Rd., Durham, NC 27703. The same ERT o r alternate

file with the CBI omitted must be submitted to the EPA via the EPA’s CDX as described earlier in this paragraph. (2) For data collected using test methods that are not supported by the EPA’s ERT as listed on the EPA’s E RT Web site, you must submit the results of the performance test to the Administrator at the appropriate address listed in §60.4.

§ 60.39f Recordkeeping guidelines. For approval, a State plan must include the recordk eeping provisions in this section. (a) Except as provided in § 60.38f(d)(2), each owne r or operator of an MSW landfill subject to the provisio ns of § 60.33f(e) must keep for at least 5 years up-to-date , readily accessible, onsite records of the design capacity r eport that triggered § 60.33f(e), the current amount of solid waste inplace, and the year-by-year waste acceptance rate. Offsite records may be maintained if they are retrievable w ithin 4 hours. Either paper copy or electronic formats are acceptable. (b) Except as provided in § 60.38f(d)(2), each owne r or operator of a controlled landfill must keep up-to-d ate, readily accessible records for the life of the control syst em equipment of the data listed in paragraphs (b)(1) through (b) (5) of this***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 305 of 324 section as measured during the initial performance test or compliance determination. Records of subsequent tes ts or monitoring must be maintained for a minimum of 5 ye ars. Records of the control device vendor specifications must be maintained

until removal. (1) Where an owner or operator subject to the provi sions of this subpart seeks to demonstrate compliance with § 60.33f(b): (i) The maximum expected gas generation flow rate a s calculated in § 60.36f(a)(1). The owner or operator may use another method to determine the maximum gas generat ion flow rate, if the method has been approved by the Admini strator. (ii) The density of wells, horizontal collectors, s urface collectors, or other gas extraction devices determi ned using the procedures specified in § 60.40f(a)(1). (2) Where an owner or operator subject to the provi sions of this subpart seeks to demonstrate compliance with § 60.33f(c) through use of an enclosed combustion device other than a boiler or process heater with a design heat input capacity equal to or greater than 44 megawatts: (i) The average temperature measured at least every 15 minutes and averaged over the same time period of t he performance test. (ii) The percent reduction of NMOC determined as sp ecified in § 60.33f(c)(2) achieved by the control device.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 306 of 324 (3) Where an owner or operator subject to the provi sions of this subpart seeks to demonstrate compliance with § 60.33f(c)(2)(i) through use of a boiler or process heater of any size: a description of the location at which the co llected gas vent stream is introduced into the boiler or proces s heater over the same time period of the performance testing. (4) Where an owner or operator subject to the provi sions of this subpart seeks to demonstrate compliance with § 60.33f(c)(1) through use of a non-enclosed flare, the flare type (i.e., steam-assisted, air-assisted, or non-assisted), all visible emission readings, heat content determination, flowrate or bypass flow rate measurements, and exit velocity de terminations made during the performance test as specified in § 60.18; and continuous records of the flare pilot flame or flar e flame monitoring and records of all periods of operations during which the pilot flame or the flare flame is absent. (5) Where an owner or operator subject to the provi sions of this subpart seeks to demonstrate compliance with § 60.33f(c)(3) through use of a landfill gas treatment system: (i) Bypass records. Records of the flow of landfill gas to, and bypass of, the treatment system. (ii) Site-specific treatment monitoring plan, to in clude:***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 307 of 324 (A) Records of filtration, de-watering, and compres sion parameters that ensure the treatment system is oper ating properly for the intended end use of the treated la ndfill gas. (B) Monitoring methods, frequencies, and operating ranges for each monitored operating parameter based on man ufacturer’s recommendations or engineering analysis for the int ended end use of the treated landfill gas. (C) Documentation of the monitoring methods and ran ges, along with justification for their use. (D) Identify who is responsible (by job title) for data

collection. (E) Processes and methods used to collect the neces sary data. (F) Description of the procedures and methods that are used for quality assurance, maintenance, and repair of a ll continuous monitoring systems. (c) Except as provided in § 60.38f(d)(2), each owne r or operator of a controlled landfill subject to the pr ovisions of this subpart must keep for 5 years up-to-date, read ily accessible continuous records of the equipment oper ating parameters specified to be monitored in § 60.37f as well as upto-date, readily accessible records for periods of operation during which the parameter boundaries established d uring the most recent performance test are exceeded.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 308 of 324 (1) The following constitute exceedances that must be recorded and reported under § 60.38f: (i) For enclosed combustors except for boilers and process heaters with design heat input capacity of 44 megaw atts (150 million British thermal unit per hour) or greater, all 3-hour periods of operation during which the average tempe rature was more than 28oC below the average combustion tempera ture during the most recent performance test at which complianc e with § 60.33f(c) was determined. (ii) For boilers or process heaters, whenever there is a change in the location at which the vent stream is introduced into the flame zone as required under paragraph (b) (3) of this

section. (2) Each owner or operator subject to the provision s of this subpart must keep up-to-date, readily accessib le continuous records of the indication of flow to the control sy stem and the indication of bypass flow or records of monthly ins pections of car-seals or lock-and-key configurations used to se al bypass lines, specified under § 60.37f. (3) Each owner or operator subject to the provision s of this subpart who uses a boiler or process heater wi th a design heat input capacity of 44 megawatts or greater to c omply with § 60.33f(c) must keep an up-to-date, readily accessib le record of all periods of operation of the boiler or process h eater.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 309 of 324 (Examples of such records could include records of steam use, fuel use, or monitoring data collected pursuant to other state, local, tribal, or federal regulatory requirements.) (4) Each owner or operator seeking to comply with t he provisions of this subpart by use of a non-enclosedflare must keep up-to-date, readily accessible continuous reco rds of the flame or flare pilot flame monitoring specified und er § 60.37f(c), and up-to-date, readily accessible recor ds of all periods of operation in which the flame or flare pi lot flame is

absent. (5) Each owner or operator of a landfill seeking to comply with § 60.33f(e) using an active collection system designed in accordance with § 60.33f(b) must keep records of es timates of NMOC emissions for periods when the collection syst em or control device is not operating. (d) Except as provided in § 60.38f(d)(2), each owne r or operator subject to the provisions of this subpart must keep for the life of the collection system an up-to-date, re adily accessible plot map showing each existing and plann ed collector in the system and providing a unique identification location label on each collector that matches the labeling o n the plot

map. (1) Each owner or operator subject to the provision s of this subpart must keep up-to-date, readily accessib le records of***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 310 of 324 the installation date and location of all newly ins talled collectors as specified under § 60.36f(b). (2) Each owner or operator subject to the provision s of this subpart must keep readily accessible documenta tion of the nature, date of deposition, amount, and location of asbestoscontaining or nondegradable waste excluded from col lection as provided in § 60.40f(a)(3)(i) as well as any nonpro ductive areas excluded from collection as provided in § 60.40f(a) (3)(ii). (e) Except as provided in § 60.38f(d)(2), each owne r or operator subject to the provisions of this subpart must keep for at least 5 years up-to-date, readily accessible rec ords of all collection and control system exceedances of the op erational standards in § 60.34f, the reading in the subsequen t month whether or not the second reading is an exceedance, and the

location of each exceedance. (f) Landfill owners or operators who convert design capacity from volume to mass or mass to volume to d emonstrate that landfill design capacity is less than 2.5 mill ion megagrams or 2.5 million cubic meters, as provided in the def inition of “design capacity”, must keep readily accessible, on site records of the annual recalculation of site-specific densit y, design capacity, and the supporting documentation. Offsite records may be maintained if they are retrievable within 4 hour s. Either paper copy or electronic formats are acceptable.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 311 of 324 (g) Landfill owners or operators seeking to demonst rate that site-specific surface methane emissions are be low 500 parts per million by conducting surface emission monitori ng under the Tier 4 procedures specified in § 60.35f(a)(6) must keep for at least 5 years up-to-date, readily accessible record s of all surface emissions monitoring and information relate d to monitoring instrument calibrations conducted accord ing to sections 8.1.2 and 10 of Method 21 of Appendix A of this part. including all of the following items: (1) Calibration records. (i) Date of calibration and initials of operator pe rforming

the calibration. (ii) Calibration gas cylinder identification, certi fication date, and certified concentration. (iii) Instrument scale(s) used. (iv) A description of any corrective action taken i f the meter readout could not be adjusted to correspond t o the calibration gas value. (v) If an owner or operator makes their own calibra tion gas, a description of the procedure used. (2) Timestamp of each surface scan reading, to the nearest minute. (3) Location of each surface scan reading. The owne r or operator must determine the coordinates using an in strument with***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 312 of 324 an accuracy of at least 3 meters. Coordinates must be in decimal degrees with at least five decimal places. (4) Monitored methane concentration (parts per mill ion) of each reading. (5) Background methane concentration (parts per mil lion)

after each instrument calibration test. (6) Adjusted methane concentration using most recen t calibration (parts per million). (7) For readings taken at each surface penetration, the unique identification location label matching the l abel specified in § 60.39f(d). (h) Except as provided in § 60.38f(d)(2), each owne r or operator subject to the provisions of this subpart must keep for at least 5 years up-to-date, readily accessible rec ords of all collection and control system monitoring data for p arameters measured in § 60.37f(a)(2) and (3). (i) Any records required to be maintained by this s ubpart that are submitted electronically via the EPA’s CDX may be

maintained in electronic format. § 60.40f Specifications for active collection systems. For approval, a State plan must include the specifi cations for active collection systems in this section. (a) Each owner or operator seeking to comply with § 60.33f(b) must site active collection wells, horizo ntal***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 313 of 324 collectors, surface collectors, or other extraction devices at a sufficient density throughout all gas producing are as using the following procedures unless alternative procedures have been approved by the Administrator. (1) The collection devices within the interior must be certified to achieve comprehensive control of surfa ce gas emissions by a professional engineer. The following issues must be addressed in the design: depths of refuse, refus e gas generation rates and flow characteristics, cover pr operties, gas system expandability, leachate and condensate manag ement, accessibility, compatibility with filling operation s, integration with closure end use, air intrusion con trol, corrosion resistance, fill settlement, resistance t o the refuse decomposition heat, and ability to isolate individu al components or sections for repair or troubleshooting without s hutting down entire collection system. (2) The sufficient density of gas collection device s determined in paragraph (a)(1) of this section must address landfill gas migration issues and augmentation of t he collection system through the use of active or passive systems at the landfill perimeter or exterior. (3) The placement of gas collection devices determi ned in paragraph (a)(1) of this section must control all g as producing***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 314 of 324 areas, except as provided by paragraphs (a)(3)(i) a nd (a)(3)(ii)

of this section. (i) Any segregated area of asbestos or nondegradabl e material may be excluded from collection if documen ted as provided under § 60.39f(d). The documentation must provide the nature, date of deposition, location and amount of asbestos or nondegradable material deposited in the area, and m ust be provided to the Administrator upon request. (ii) Any nonproductive area of the landfill may be excluded from control, provided that the total of all exclud ed areas can be shown to contribute less than 1 percent of the t otal amount of NMOC emissions from the landfill. The amount, lo cation, and age of the material must be documented and providedto the Administrator upon request. A separate NMOC emissio ns estimate must be made for each section proposed for exclusio n, and the sum of all such sections must be compared to the NM OC emissions

estimate for the entire landfill. (A) The NMOC emissions from each section proposed f or exclusion must be computed using the following equa tion:

= 2  (    )(  ) (3.6		10  )

Where:

Qi = NMOC emission rate from the ith section, megag rams

per year. k = Methane generation rate constant, year−1.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 315 of 324 Lo = Methane generation potential, cubic meters per

megagram solid waste. Mi = Mass of the degradable solid waste in the ith

section, megagram. ti = Age of the solid waste in the ith section, yea rs. CNMOC = Concentration of NMOC, parts per million by volume. 3.6×10−9 = Conversion factor. (B) If the owner/operator is proposing to exclude, or cease gas collection and control from, nonproductive phys ically separated (e.g., separately lined) closed areas tha t already have gas collection systems, NMOC emissions from ea ch physically separated closed area must be computed using either the equation in § 60.35f or the equation in paragraph (a)(3)(ii) (A) of this

section. (iii) The values for k and CNMOC determined in fiel d testing must be used if field testing has been perf ormed in determining the NMOC emission rate or the radii of influence (the distance from the well center to a point in th e landfill where the pressure gradient applied by the blower o r compressor approaches zero). If field testing has not been per formed, the default values for k, Lo, and CNMOC provided in § 6 0.35f or the alternative values from § 60.35f must be used. The mass of nondegradable solid waste contained within the give n section may

be subtracted from the total mass of the section wh en estimating emissions provided the nature, location, age, and a mount of the***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 316 of 324 nondegradable material is documented as provided in paragraph (a)(3)(i) of this section. (b) Each owner or operator seeking to comply with § 60.33f(b) must construct the gas collection devices using the following equipment or procedures: (1) The landfill gas extraction components must be constructed of polyvinyl chloride (PVC), high densi ty polyethylene (HDPE) pipe, fiberglass, stainless ste el, or other nonporous corrosion resistant material of suitable dimensions to: convey projected amounts of gases; withstand in stallation, static, and settlement forces; and withstand planne d overburden or traffic loads. The collection system must extendas necessary to comply with emission and migration standards. Co llection

devices such as wells and horizontal collectors mus t be perforated to allow gas entry without head loss suf ficient to impair performance across the intended extent of co ntrol. Perforations must be situated with regard to the ne ed to prevent

excessive air infiltration. (2) Vertical wells must be placed so as not to enda nger underlying liners and must address the occurrence o f water

within the landfill. Holes and trenches constructedfor piped

wells and horizontal collectors must be of sufficie nt crosssection so as to allow for their proper constructio n and completion including, for example, centering of pip es and***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 317 of 324 placement of gravel backfill. Collection devices mu st be designed so as not to allow indirect short circuiti ng of air into the cover or refuse into the collection system or gas into the air. Any gravel used around pipe perforations s hould be of a dimension so as not to penetrate or block perforati ons. (3) Collection devices may be connected to the coll ection header pipes below or above the landfill surface. T he connector assembly must include a positive closing throttle v alve, any necessary seals and couplings, access couplings and at least one sampling port. The collection devices must be const ructed of PVC, HDPE, fiberglass, stainless steel, or other no nporous material of suitable thickness. (c) Each owner or operator seeking to comply with § 60.33f(c) must convey the landfill gas to a control system in compliance with § 60.33f(c) through the collection header pipe(s). The gas mover equipment must be sized to h andle the maximum gas generation flow rate expected over the intended use period of the gas moving equipment using the follow ing procedures: (1) For existing collection systems, the flow data must be used to project the maximum flow rate. If no flow d ata exist, the procedures in paragraph (c)(2) of this section must be used. (2) For new collection systems, the maximum flow ra te must be in accordance with § 60.36f(a)(1).***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 318 of 324 § 60.41f Definitions. Terms used but not defined in this subpart have the meaning given them in the Clean Air Act and in subparts A a nd B of this part.Active collection system means a gas collection sys tem that uses gas mover equipment.

Active landfill means a landfill in which solid was te is being placed or a landfill that is planned to accep t waste in

the future.

Administrator means the Administrator of the U.S. Environmental Protection Agency or his/her authoriz ed representative or the Administrator of a State Air Pollution Control Agency.

Closed landfill means a landfill in which solid was te is no longer being placed, and in which no additional sol id wastes will be placed without first filing a notification of modification as prescribed under § 60.7(a)(4). Once a notification of modification has been filed, and ad ditional solid waste is placed in the landfill, the landfill is no longer

closed. Closed landfill subcategory means a closed landfill that has submitted a closure report as specified in § 60 .38f(f) on or before [ insert date of publication in the Federal Register ].***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 319 of 324 Closure means that point in time when a landfill be comes a closed landfill. Commercial solid waste means all types of solid was te generated by stores, offices, restaurants, warehous es, and other nonmanufacturing activities, excluding residential and

industrial wastes. Controlled landfill means any landfill at which col lection and control systems are required under this subpart as a result

of the NMOC emission rate. The landfill is consider ed controlled at the time a collection and control system design plan is submitted in compliance with § 60.33f(e)(2). Design capacity means the maximum amount of solid w aste a landfill can accept, as indicated in terms of volum e or mass in the most recent permit issued by the state, local, or tribal agency responsible for regulating the landfill, plu s any inplace waste not accounted for in the most recent pe rmit. Disposal facility means all contiguous land and str uctures, other appurtenances, and improvements on the land u sed for the disposal of solid waste.

Emission rate cutoff means the threshold annual emi ssion rate to which a landfill compares its estimated emi ssion rate to determine if control under the regulation is requir ed.

Enclosed combustor means an enclosed firebox which maintains a relatively constant limited peak temper ature***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 320 of 324 generally using a limited supply of combustion air. An enclosed

flare is considered an enclosed combustor. Flare means an open combustor without enclosure or shroud. Gas mover equipment means the equipment (i.e., fan, blower, compressor) used to transport landfill gas through the header system. Household waste means any solid waste (including ga rbage, trash, and sanitary waste in septic tanks) derived from households (including, but not limited to, single a nd multiple residences, hotels and motels, bunkhouses, ranger s tations, crew quarters, campgrounds, picnic grounds, and day-use recreation areas). Household waste does not include fully segr egated yard waste. Segregated yard waste means vegetative matte r resulting exclusively from the cutting of grass, the pruning and/or removal of bushes, shrubs, and trees, the weeding o f gardens, and other landscaping maintenance activities. House hold waste does not include construction, renovation, or demol ition wastes. Industrial solid waste means solid waste generated by manufacturing or industrial processes that is not a hazardous waste regulated under Subtitle C of the Resource Co nservation and Recovery Act, parts 264 and 265 of this title. Such waste may include, but is not limited to, waste resulting from the following manufacturing processes: electric power g eneration; fertilizer/agricultural chemicals; food and relatedproducts/by-***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 321 of 324 products; inorganic chemicals; iron and steel manuf acturing; leather and leather products; nonferrous metals manufacturing/foundries; organic chemicals; plastic s and resins manufacturing; pulp and paper industry; rubber and miscellaneous plastic products; stone, glass, clay, and concrete products; textile manufacturing; transportation equipment; an d water treatment. This term does not include mining waste or oil and gas waste. Interior well means any well or similar collection component located inside the perimeter of the landf ill waste. A perimeter well located outside the landfilled waste is not an

interior well.

Landfill means an area of land or an excavation in which wastes are placed for permanent disposal, and that is not a land application unit, surface impoundment, injection we ll, or waste pile as those terms are defined under §257.2 of thi s title. Lateral expansion means a horizontal expansion of t he waste boundaries of an existing MSW landfill. A lateral e xpansion is

not a modification unless it results in an increase in the design capacity of the landfill. Modification means an increase in the permitted vol ume design capacity of the landfill by either lateral o r vertical expansion based on its permitted design capacity as of July 17,***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 322 of 324 2014. Modification does not occur until the owner o r operator

commences construction on the lateral or vertical e xpansion. Municipal solid waste landfill or MSW landfill mean s an entire disposal facility in a contiguous geographic al space where household waste is placed in or on land. An M SW landfill may also receive other types of RCRA Subtitle D was tes (§257.2 of this title) such as commercial solid waste, nonh azardous sludge, conditionally exempt small quantity generat or waste, and

industrial solid waste. Portions of an MSW landfill may be separated by access roads. An MSW landfill may be p ublicly or privately owned. An MSW landfill may be a new MSW l andfill, an existing MSW landfill, or a lateral expansion. Municipal solid waste landfill emissions or MSW lan dfill emissions means gas generated by the decomposition of organic waste deposited in an MSW landfill or derived from the evolution of organic compounds in the waste. NMOC means nonmethane organic compounds, as measure d according to the provisions of § 60.35f. Nondegradable waste means any waste that does not d ecompose through chemical breakdown or microbiological activ ity. Examples are, but are not limited to, concrete, municipal wa ste combustor ash, and metals.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 323 of 324 Passive collection system means a gas collection sy stem that solely uses positive pressure within the landf ill to move the gas rather than using gas mover equipment. Protectorate means American Samoa, the Commonwealth of Puerto Rico, the District of Columbia, Guam, the No rthern Mariana Islands, and the Virgin Islands. Sludge means the term sludge as defined in 40 CFR 2 58.2.

Solid waste means the term solid waste as defined i n 40 CFR

258.2. State means any of the 50 United States and the protectorates of the United States. State plan means a plan submitted pursuant to secti on 111(d) of the Clean Air Act and 40 CFR part 60, sub part B that implements and enforces 40 CFR part 60, subpart Cf. Sufficient density means any number, spacing, and combination of collection system components, includ ing vertical wells, horizontal collectors, and surface collector s, necessary to maintain emission and migration control as deter mined by measures of performance set forth in this part.

Sufficient extraction rate means a rate sufficient to maintain a negative pressure at all wellheads in th e collection system without causing air infiltration, including any wellheads connected to the system as a result of expansion or excess surface emissions, for the life of the blower.***E.O. 12866 Review-Draft-Do Not Cite, Quote or Re lease During Review*** Page 324 of 324 Treated landfill gas means landfill gas processed i n a treatment system as defined in this subpart. Treatment system means a system that filters, de-wa ters, and compresses landfill gas for sale or beneficial use. Untreated landfill gas means any landfill gas that is not treated landfill gas.