*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 1 of 147 EO12866_AirptDeicingEffGdl_2040-AE69 FR FRN_20110525.docx ENVIRONMENTAL PRO TECTION AGENCY 40 CFR Part 122 40 CFR Part 449 [EPA-HQ-OW-2004-0038. FRL- ] RIN 2040-AE69

Effluent Limitation Guidelines and New Source Performance Standards for the Airport Deicing Category AGENCY: Environmental Protection Agency (EPA). ACTION: Final Rule. SUMMARY: EPA is promulgating technology-based e ffluent limitation guidelines (ELGs) and new source performance standards (NSPS) under the Clean Water Act (CWA) for discharges from airport deicing operations. The requirements generally apply to wastewater associated with the deicing of aircraft and airfield pavement at primary airports. The rule will require all such airports to comply with require ments based on discontinuing use of pavement deicers containing urea in favor of less toxic products or, alternat ively, to meet ammonia limits for their direct discharges. The rule will require a subset of these airports, those th at use greater than or equal to 60,000 gallons of normalized ADF per deicing seas on, to meet requirements based on collection of deicing fluid and treatment of the collected fluid. The ELGs will be incorporated into NPDES permits issued by EPA or states. EPA e xpects compliance with this regulation to reduce the discharge of deicing-related pollutants by 33 million pounds per year. EPA estimates the annual cost of the rule is $78 million. DATES: This final rule is effective on [insert 30 days after publica tion in the Federal Register]. ADDRESSES: EPA has established a docket for th is action under Docket ID No. EPA–HQ– OW–2004–0038. All documents in the docket are listed on the website at*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 2 of 147 http://www.regulations.gov. Although listed in the index, some information is not publicly available, e.g., CBI or other information whose disc losure is restricted by statute. Certain other material, such as copyrighted material, is not pl aced on the Internet and will be publicly available only in hard copy form. Publicly available docke t materials are availabl e either through the docket website or in hard copy at the Office of Water Docket, EPA We st Building Room 3334, 1301 Constitution Ave, NW, Washington, DC. Th e Public Reading Room is open from 8:30 a.m. to 4:30 p.m., Monday through Friday, exclud ing legal holidays. The telephone number for the Public Reading Room is 202-566-1744, and th e telephone number for the Office of Water Docket is 202-566-1752. FOR FURTHER INFORMATION CONTACT: Eric Strassler, Engineering and Analys is Division, telephone: 202-566-1026; e-mail: strassler.eric@epa.gov.

SUPPLEMENTARY INFORMATION: Regulated Entities Entities regulated by this action include:
Category Example of Regulated Entity North American Industry Classification System Code Industry Primary airports 481, 4881

This section is not intended to be exhaus tive, but rather provid es a guide for readers regarding entities likely to be re gulated by this action. Other type s of entities that do not meet the above criteria could also be regulated. To determine whether your facility is regulated by this action, you should carefully examine the applicability criteria listed in §449.01 and the*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 3 of 147 definitions in §449.02 of the rule and detailed furthe r in Section V of this preamble. If you still have questions regarding the appli cability of this action to a partic ular entity, consult one of the persons listed for technical information in the preceding FOR FURTHER INFORMATION CONTACT section. Supporting Documentation Today’s final rule is supported by a number of documents including:

 Technical Development Document for Fina l Effluent Limitation Guidelines and Standards for the Airport Deicing Cate gory (TDD), Document No. EPA-821-R-_____;

 Economic Analysis for Final Effluent Lim itation Guidelines and Standards for the Airport Deicing Category (EA) , Document No. EPA-821-R-______;

 Environmental Impact and Benefit Assessment for Final Effluent Limitation Guidelines and Standards for the Airport Deicing Category (EIB), Document No. EPA-821-R-

______. These documents are available in the public re cord for this rule and on EPA’s website at http://epa.gov/guide/airport . Overview The preamble describes the terms, acronyms, an d abbreviations used in this notice; the background documents that support the regulations; th e legal authority of th ese rules; a summary of the final rule; background information; and the technical and economic methodologies used by the Agency to develop these regulations. Table of Contents I. Legal Authority 6 II. Purpose and Summary of the Final Rule 7 III. Background 7 A. Clean Water Act 7*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 4 of 147 B. NPDES Permits 9 1. General Permits 10 2. Individual Permits 11 C. Effluent Guidelines and Standards Program 12 1. Best Practicable Control Technol ogy Currently Available (BPT) 12 2. Best Conventional Pollutant Control Technology (BCT) 13 3. Best Available Technology Economically Achievable (BAT) 13 4. New Source Performance Standards (NSPS) 14 5. Pretreatment Standards fo r Existing Sources (PSES) 14 6. Pretreatment Standards for New Sources (PSNS) 15 D. Proposed Rule 15 1. ADF Collection 16 2. Numeric Limit for Collected ADF 17 3. Airfield Pavement Deicers 17 4. Other Technology Basis Considered 17 IV. Summary of Significant Comments a nd Changes to Rule Since Proposal 17 A. ADF Collection Requirem ents and Applicability 17 1. Applicability of ADF Collection/Discha rge Requirement for Existing Sources 18 2. Collection Requirement 20 B. New Source Definition and ADF Co llection Requirement Applicability 22 C. Extension of Applicability Date 24 D. Deicing for Safe Taxiing 26 E. Glycol Collection Vehicles 26 F. Effluent Limitation for Chemical Oxygen Demand 27 1. COD as an Indicator for ADF 27 2. Arguments that EPA Must Address BOD 5 31 3. COD Versus Soluble COD as a Regulated Pollutant 34 V. Scope and Applicability of the Final Rule 34 A. Subcategorization 35 B. Industry Description 36 C. Wastewater Sources and Wa stewater Characteristics 38 1. Aircraft Deicing 38 2. Airfield Pavement Deicing 39 D. Control and Treatment Technol ogies for the Aviation Industry 40 1. Aircraft Deicing Fluid Collection Technologies 41 2. ADF-Contaminated Wastewater Treatment Technologies 43 3. Pollution Prevention Technologies 44 4. Airfield Pavement Deicing Control Technologies 47 E. Regulated Pollutants 47 VI. Final Regulation 47 A. BPT and BCT 47 B. BAT 48 1. Airfield Deicing: Product Substitution of Pavement Deicers Containing Urea 48 2. Aircraft Deicing: ADF Collection Requirements and Effluent Limitations 50 3. BAT Options Selection 53 C. NSPS 54*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 5 of 147 D. PSES and PSNS 55 VII. Technology Costs and Pollutant Reductions 57 A. Compliance Costs 57 1. Overview 57 2. Approach for Estimating Airfie ld Pavement Deicing Costs 58 3. Approach for Developing Aircraft Deic ing Costs 59 4. Calculation of National Costs 61 B. Approach to Estimating Pollutant Reductions 62 1. Overview 62 2. Sources and Use of Available Data 63 C. Approach to Determining Long-Term Av erages, Variability Factors and Effluent Limitation Guidelines and Standards 68 1. Criteria Used to Select Data as the Basis of the Limitations 68 2. Data Used As Basis of the Effluent Limitations 70 3. Statistical Percentile Basis for Limitations 71 4. Rationale for Establishing Limitation on Week ly Averages Instead of Monthly Averages for COD in Effluent Discharges 73 5. Rationale for Promulgating a Limitation On ly for Daily Discharges of Ammonia in Effluent Discharges 74 6. Calculation of Limitations for COD and Ammonia 75 7. Derivation of Long-Term Average for COD and Ammonia: Target Level for Treatment 76 8. Engineering Review of Effluent Limitations 77 VIII. Economic Analysis 79 A. Introduction 79 B. Annualized Compliance Cost Estimates 79 C. Economic Impact Methodologies 82 1. Cost Annualization 83 2. Airport Impact Methodology 84 3. Co-Permittee Airline Impact Methodology 88 D. Results of Impact Analysis 92 1. Results of Airport Impact Analysis 92 2. Results of Co-permittee Airline Impact Analysis 97 3. Economic Achievability 98 E. Economic Impacts for New Sources 100 F. Cost and Pollutant Reduction Comparison 102 G. Small Business Analysis 103 IX. Environmental Assessment 105 A. Environmental Impacts 105 B. Environmental Benefits 107 X. Non-Water Quality Environmental Impacts 108 A. Energy Requirements 108 B. Air Emissions 110 1. Emissions from GCV Collection 110 2. Emissions from AFB Treatment Systems 111 C. Solid Waste Generation 111*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 6 of 147 XI. Regulatory Implementation 112 A. Relation of ELGs to NPDES Permits 112 B. Applicability Date 113 C. Demonstrating Compliance with the ADF Collection Requirement 113 D. Permit Application Requirements 116 E. COD Effluent Monitoring for Direct Dischargers 116 Direct dischargers are required by the final rule to sample and analy ze the discharges from their treatment system for COD prior to any dilution or co-mingling with other non-deicing waters. The sampling frequency, analytical me thod and reporting procedures are determined by the permit authority. Permittees must follow the sampling protocol specified in Appendix A of Part 449. 116 F. Alternative Compliance Option for Pavement Deicers Containing Urea 116 G. Best Management Practices 117 H. Upset and Bypass Provisions 117 I. Variances and Modifications 118 1. Fundamentally Different Factors Variance 118 2. Economic Variances 120 3. Water Quality Variances 120 J. Information Resources 120 XII. Statutory and Executive Order Reviews 121 A. Executive Order 12866: Regulatory Planni ng and Review and Executive Order 13563: Improving Regulation and Regulatory Review 121 B. Paperwork Reduction Act 121 C. Regulatory Flexibility Act 123 D. Unfunded Mandates Reform Act 124 E. Executive Order 13132: Federalism 125 F. Executive Order 13175: Consultation and Coor dination with Indian Tribal Governments 126 G. Executive Order 13045: Protection of Childre n from Environmental Health and Safety Risks 126 H. Executive Order 13211: Energy Effects 126 I. National Technology Transfer Advancement Act 127 J. Executive Order 12898: Federal Actions to Address Environmental Justice in Minority Populations and Low-Income Populations 127 K. Congressional Review Act 128 Appendix A: Abbreviations and Defin itions Used in This Document 128 I. Legal Authority EPA is promulgating this regulation unde r the authorities of sections 301, 304, 306, 308, 402 and 501 of the Clean Water Act (C WA), 33 U.S.C. 1311, 1314, 1316, 1318, 1342 and 1361 and pursuant to the Pollution Prevention Act of 1990, 42 U.S.C. 13101 et seq.*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 7 of 147 II. Purpose and Summary of the Final Rule Commercial airports and ai r carriers conduct deicing ope rations as required by the Federal Aviation Administration (FAA). Airport di scharges from deicing operations may affect water quality in surrounding communities, includ ing reductions in dissolved oxygen, fish kills, reduced organism abundance and species divers ity, contamination of drinking water sources (both surface and groundwater), creation of noxious odors and disc olored water in residential areas and parkland, and other effects. Today EPA is promulgating effluent limitation guidelines (ELGs) and new source performance standards (NSPS) for the Airport De icing Point Source Category. The regulations address control of the wastewater discharges from deicing operations based on product substitution, wastewater collection practices us ed by airports, and trea tment practices for the collected wastewater. Certain air ports within the scope of this ru le are required to collect spent aircraft deicing fluid (ADF) a nd meet numerical discharge limits . Those airports and certain additional airports performing airfield pavement deicing are to use non-ur ea-containing deicers, or alternatively, meet a numeric effluent limitation for ammonia. The requirements are implemented in CWA discharge permits. The rule requirements and the technologies that serve as the basis for the ELGs are explained in Sections V, VI and VII of this preamble.

III. Background A. Clean Water Act Congress passed the Federal Water Pollution Control Act Amendments of 1972, also known as the Clean Water Act (CWA), to “resto re and maintain the chemical, physical, and*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 8 of 147 biological integrity of the nation's waters.” (33 U.S.C. 1251(a)). The CWA establishes a comprehensive program for protecting our nation' s waters. Among its core provisions, the CWA prohibits the discharge of pollutants from a poi nt source to waters of the U.S. except as authorized under the CWA. Under section 402 of the CWA, EPA authorizes discharges by a National Pollutant Discharge Elimination System (NPDES) permit. The CWA also authorizes EPA to establish national technology-based efflue nt limitation guidelines and standards (effluent guidelines or ELGs) for discharges from different categories of point sources , such as industrial, commercial and public sources. In addition, the CWA authorizes EPA to promulgate nationally app licable pretreatment standards that restrict pollutant discharges from facilities that discharge wastewater indirectly through sewers flowing to publicly owned treatm ent works (POTWs). See section 307(b) and (c), 33 U.S.C. 1317(b) and (c). National pret reatment standards are established for those pollutants in wastewater from i ndirect dischargers that may pa ss through, interfere with or are otherwise incompatible with PO TW operations. Generally, pretr eatment standards are designed to ensure that wastewaters from direct and indi rect industrial discharger s are subject to similar levels of treatment. In addition, POTWs are required to implement local treatment limits applicable to their industrial in direct dischargers to satisfy any local requirements. See 40 CFR
403.5. Direct dischargers must comply with efflue nt limitations in NPDES permits. Indirect dischargers, who discharge through POTWs, must comply with pretreatment standards. Technology-based effluent limitations in NPDES pe rmits are derived from effluent limitation guidelines (CWA sections 301 and 304, 33 U.S.C. 1311 and 1314) and new source performance standards (sec. 306) promulgated by EPA, or based on best professiona l judgment where EPA*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 9 of 147 has not promulgated an applicable effluent gui deline or new source performance standard (CWA section 402(a)(1)(B), 33 U.S.C. 1342(a)(1)(B)). Additional limitations based on water quality standards (CWA section 301(b)(1)(C), 33 U.S.C. 1311( b)(1)(C)) are also requi red to be included in the permit in certain circumstances. The ELG s are established by regul ation for categories of industrial dischargers and are base d on the degree of control that can be achieved using various levels of pollution control technology. EPA promulgates national effluent limitation gui delines and standards of performance for major industrial categories for thre e classes of pollutants: (1) c onventional pollutants (i.e., total suspended solids, oil and grease, biochemical oxygen demand, fecal coliform, and pH); (2) toxic pollutants (e.g., toxic metals such as chromium, lead, nickel, and zinc; toxic organic pollutants such as benzene, benzo-a-pyrene, phenol, and naphthalene); and (3) non- conventional pollutants (e.g., ammonia-N, formaldehyde, and phosphorus). B. NPDES Permits Section 402 of the CWA requires permits for point source discharges of pollutants to waters of the United States. In most states, the permits are issued by a state agency that has been authorized by EPA. Currently 46 states and 1 U.S. territory are authorized to issue NPDES permits. In the other states and territories, EPA issues the permits. Section 402(p) of the Act, added by the Water Quality Act of 1987 (Pub. L. 100-4, February 4, 1987), requires stormwat er dischargers “associ ated with industrial activity” to be covered under an NPDES permit. In its initial stormwater permit regulations, called the “Phase I” stormwater regulations (55 FR 47990, Novemb er 16, 1990), EPA designated air transportation facilities, including both airlines and airpor ts, which have vehicle maintenance shops (including vehicle rehabilitation, mechanical repairs, painting, fueling, and lubrication), equipment cleaning*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 10 of 147 operations, or airport deicing operations as subject to NPDES stormwater permitting requirements. See 40 CFR 122.26(b)(14)(viii). Airport stormwater discharges may be c ontrolled under a general NPDES permit, which covers multiple facilities with similar types of operations and/or wastestreams, or by an individual permit. (An airport may have additional NPDES permits for non-stormwater discharges, such as from equipment repair and maintenance facilities. The following discussion pertains only to airport stormwater permits.) 1. General Permits Currently most airport deicing discharges are covered by a general permit issued either by EPA or by an NPDES-authorized state agency . In most areas where EPA is the permit authority, the Multi-Sector General Permit (MSGP) covers airport deici ng discharges (73 FR 56572, September 29, 2008). Many NPDES-authori zed state agencies have issued general permits in their respective jurisdictions with re quirements similar to the MSGP. An airport seeking coverage under a general permit submits a Notice of Intent(NOI) to the permit authority rather than a detailed permit application. By submitting an NOI, the permittee is agreeing to comply with the conditions inthe final general permit. For airports, the major requirements of the current MSGP are:

 develop a stormwater pollution prevention plan (SWPPP), including a drainage area site map, documentation of measures used for management of deicing contaminated stormwater, an evaluation of runway and airc raft deicing operati ons, and implementation of a program to control or manage de icing contaminated stormwater, including consideration of various listed control practices;*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 11 of 147  implement deicing source reduction measures , including minimizing or eliminating the use of urea and glycol-containing deicing chemicals; minimizing contamination of deicing contaminated stormwater from runway and aircraft deicing operations; evaluating whether over-application of deicing chemicals occurs; and consider use of various listed source control measures;

 for airports using over 100,000 ga llons of glycol-based deicin g chemicals and/or 100 tons or more of urea containing deicers annually, monitor discharges quarterly for the first four quarters of the permit cycle, for the following pollutants: biochemical oxygen demand (BOD 5 ), chemical oxygen demand (COD), ammonia and pH;

 if the average of the four monitoring values for any parameter exceeds its benchmark, implement additional control measures where feasible, and continue monitoring;

 conduct an annual site inspection during the deicing season, and during periods of actual deicing operations if possible; and routine facility inspecti ons at least monthly during the deicing season. EPA expects to modify the MSGP when the next permit is issued, to conform to today’s final Airport Deicing rule. 2. Individual Permits Some EPA and state NPDES-permitting authori ties have required certain airports to obtain individual permits. In these situations, an airport must submit a detailed application and the permit authority develops specific requirements for the facility. Some individual permits cont ain specialized requirements for monitoring and/or best management practices. Some of these permits al so contain numeric water quality-based effluent*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 12 of 147 limitations (WQBELs). Information on water qu ality-based permitting is available on EPA's website at http://cfpub.epa.gov/npdes/ge neralissues/watertechnology.cfm . C. Effluent Guidelines and Standards Program Effluent guidelines and new source perf ormance standards are technology-based regulations that are developed by EPA for a category of dischargers. These regulations are based on the performance of control and treatment t echnologies. The legisl ative history of CWA section 304(b), which is the heart of the effluent guidelines program, describes the need to press toward higher levels of c ontrol through research and deve lopment of new processes, modifications, replacement of obsolete plans and processes, and other improvements in technology, taking into account the cost of controls. Congress al so stated that EPA need not consider water quality impacts on individual water bodies as the guidelines are developed. See Statement of Senator Muskie (Oct. 4, 1972), re printed in Legislative History of the Water Pollution Control Act Amendments of 1972, at 170. (U.S. Senate, Committee on Public Works, Serial No. 93-1, January 1973.) There are four types of standards applicable to direct dischargers (dischargers to surface waters), and two standards applicable to indi rect dischargers (disch arges to publicly owned treatment works or POTWs). 1. Best Practicable Control Tec hnology Currently Available (BPT) Traditionally, EPA establishes BPT effluent limitations based on the average of the best performances of facilities within the industry, grouped to reflect various ages, sizes, processes, or other common characteristics. EPA may promulgate BPT effluent limits for conventional, toxic, and non-conventional pollutants. In specifying BP T, EPA looks at a number of factors. EPA first considers the cost of achieving effluent re ductions in relation to the effluent reduction*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 13 of 147 benefits. The Agency also considers the age of the equipment and facilities, the processes employed, engineering aspects of the control technologies, any require d process changes, nonwater quality environmental impacts (including ener gy requirements), and such other factors as the Administrator deems appropriate. See CWA sec. 304(b)(1)(B). If, however, existing performance is uniformly inadequate, EPA may es tablish limitations based on higher levels of control than currently in place in an industrial category when based on an Agency determination that the technology is available in another category or subcat egory, and can be practically applied. 2. Best Conventional Pollutant Control Technology (BCT) The 1977 amendments to the CWA required EPA to identify additional levels of effluent reduction for conventional pollutants associated with BCT technology for discharges from existing industrial point sources. In addition to othe r factors specified insection 304(b)(4)(B), the CWA requires that EPA establish BCT limitati ons after consideration of a two part “costreasonableness” test. EPA explained its methodology for the development of BCT limitations in July 1986 (51 FR 24974). Section 304(a)(4) designates the followi ng as conventional pollutants: biochemical oxygen demand measured over five days (BOD 5 ), total suspended solids (TSS), fecal coliform, pH, and any additional pollutants defined by the Administrator as conventional. The Administrator designated oil and grease as an additional conventional pollutant on July 30, 1979 (44 FR 44501; 40 CFR 401.16). 3. Best Available Technology Economically Achievable (BAT) BAT represents the second leve l of stringency for controllin g direct discharge of toxic and nonconventional pollutants. In general, BAT effluent limitati on guidelines represent the best economically achievable performance of facilities inthe industrial subcategory or category. The*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 14 of 147 factors considered in assessing BAT include the cost of achieving BAT effluent reductions, the age of equipment and facilities involved, the process employed, potential process changes, and non-water quality environmental im pacts including energy requirem ents, and such other factors as the Administrator deems appropriate. The Agen cy retains considerable discretion in assigning the weight to be accorded these factors. An a dditional statutory factor considered in setting BAT is economic achievability. Generally, EPA dete rmines economic achievability on the basis of total costs to the industry and the effect of compliance with BAT limitations on overall industry and subcategory financial conditions. As with BPT, where existing performance is uniformly inadequate, BAT may reflect a hi gher level of performance than is currently being achieved based on technology transferred from a different subcategory or category. BAT may be based upon process changes or internal controls, ev en when these technologies are not common industry practice. 4. New Source Performance Standards (NSPS) New Source Performance Standard s reflect effluent reductions that are achievable based on the best available demonstrated control technology (BADCT). Owners of new facilities have the opportunity to install the best and most efficient produc tion processes and wastewater treatment technologies. As a resu lt, NSPS should represent the most stringent contro ls attainable through the application of the best available demonstrated control technology for all pollutants (that is, conventional, nonconventio nal, and priority pollutants). In establishing NSPS, EPA is directed to take into consider ation the cost of ach ieving the effluent re duction and any non-water quality environmental impact s and energy requirements. 5. Pretreatment Standards fo r Existing Sources (PSES)*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 15 of 147 Section 307(b) calls for EPA to issue pretreat ment standards for discharges of pollutants to publicly owned treatment works (POTW). Pr etreatment Standards for Existing Sources are designed to prevent the discharge of pollutants th at pass through, interfere with, or are otherwise incompatible with the operation of POTWs. Categorical pretreatmentstandards are technologybased and are analogous to BPT and BAT efflue nt limitation guidelines. See CWA sections 301((b)(1)(B) and 301(b)(2)(A)), 33 U.S.C. 1311(b)(1)(B) and 1311(b)(2 )(A). The General Pretreatment Regulations, which set forth the fr amework for the implementation of categorical pretreatment standards, are found at 40 CFR part 403. These regulations establish pretreatment standards that apply to a ll non-domestic dischargers. See 52 FR 1586 (Jan. 14, 1987). 6. Pretreatment Standards for New Sources (PSNS) Section 307(c) of the Act calls for EPA to promulgate pretreatment standards for new sources. Such pretreatment standards must prev ent the discharge of any pollutant into a POTW that may interfere with, pass through, or may ot herwise be incompatible with the POTW. EPA promulgates pretreatment standards for new s ources based on best available demonstrated technology for new sources. New indirect discharg ers have the opportunity to incorporate into their facilities the best available demonstrated technologies. The Agency typically considers the same factors in promulgating PSNS as it considers in promulgating NSPS. D. Proposed Rule EPA published a proposed rule for the Ai rport Deicing Category on August 28, 2009 (74 FR 44676). The proposed rule covered primary commercial airports that conduct deicing operations and have 1,000 or more annual jet departur es. An existing airport in the scope of the proposal would have been required to certify that it uses airfield paveme nt deicers that do not*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 16 of 147 contain urea, or alternatively, meet an effluent limitation for ammonia. Additionally, in-scope airports with 10,000 or more annual depa rtures would have been required to:

 Collect at least a specified pr oportion (either 20 or 60 percent, based on size) of available aircraft deicing fluid (ADF) afte r it is sprayed on aircraft; and

 Meet a specified numeric effluent limit for ADF wastewater collected and discharged directly. As proposed, all in-scope new source discharg ers had the same airfield pavement deicing requirements as existing sources and were requir ed to collect 60 percen t of available ADF and meet the specified numeric limit for direct discharg es of the collected fluid. EPA estimated that the proposed rule would apply to 218 existing air ports: 110 airports for both the pavement deicer and ADF collection and discharge requirements, and another 108 airports for the pavement deicer requirement only. Of those 218 airports, the Agency estimated th at 148 airports were already in compliance with the proposed requirements. 1. ADF Collection The proposed rule would have required all existing primary airports that have 10,000 or more annual departures to collect at least 20 pe rcent of available ADF. The 20 percent collection requirement was based on the estimated performa nce of glycol collection vehicles (GCVs). A subset of this group, those primary airports th at use 460,000 or more gallons of normalized ADF annually, would be required to co llect at least 60 per cent of all available ADF. (As defined at proposed §449.2, normalized ADF is ADF less any wa ter added by the manufacturer or customer before ADF application.) This collection requi rement was based on the estimated performance of centralized deicing pads (CDPs). In-scope primary airports with less than 10,000 annual*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 17 of 147 departures would not be required to collect their available deicing fluid or meet associated discharge limitations and would have continued to be subject to BPJ permitting requirements. 2. Numeric Limit for Collected ADF For airports discharging collected ADF dir ectly to surface waters, the proposal would have required them to meet numeric efflue nt limitations for chemical oxygen demand (COD). The limits were based on anaerobic fl uidized bed (AFB) treatment technology. 3. Airfield Pavement Deicers EPA proposed BAT for direct dischargers a ssociated with airfiel d pavement deicing based on product substitution. Specifically, EPA based BAT on discontinuing use of pavement deicers containing urea in favor of alternative, less toxic products that are also effective and not harmful to aircraft. 4. Other Technology Basis Considered In the proposed rule, in a ddition to centralized deicing pads and glycol collection vehicles, EPA described plug-and- pump technology with GCVs as a possible BAT basis for an ADF collection requirement, and calculated the cost of this t echnology. This technology, when used in combination with GCVs, is estimated to collect at least 40 percent of available ADF.

IV. Summary of Significant Comments a nd Changes to Rule Since Proposal A. ADF Collection Requirements and Applicability For BAT, EPA has revised the basis for and the applicability of the ADF collection and discharge requirement. As explained in Section VII.E of the proposed rule, EPA proposed as its lead option a combination of three different collection/discharge requirements for in-scope airports:*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 18 of 147  Airports with less than 10,000 annual departures were not required to collect their spent deicing fluid or meet associated discharge limitations, but were subject to BPJ permit requirements;

 Airports with 10,000 or more annual departures that use less than 460,000 gallons of normalized ADF per deicing season were requir ed to collect 20 percent of available ADF based on GCVs and, if discharged directl y, meet associated numerical discharge limitations based on bi ological treatment.

 Airports with 10,000 or more annual departur es that use 460,000 or more gallons of normalized ADF per deicing season were requir ed to collect 60 percent of available ADF based on CDPs and, if discharged directl y, meet associated numerical discharge limitations based on bi ological treatment. The proposal also discussed collection and tr eatment of 40 percent of the available ADF, based on plug and pump collection technology togeth er with use of GCVs. EPA had rejected this collection technology because it estimated th e costs to be comparable to those of CDPs, while CDPs achieve greater ADF collection. 1. Applicability of ADF Collection/Disc harge Requirement for Existing Sources Commenters raised multiple concerns with EPA’s proposed approach. First, commenters stated that annual aircraft departures are not a good proxy for ADF usage. For example, they explained that an airport in the very southern portion of the US c ould have significant departures but use little ADF. Second, comme nters requested that EPA consid er a de minimis cut-off to account for defrosting. Under the proposal, defros ting would be counted towards the volume of ADF required to be collected, yet commenters cl aim that it evaporates and is unable to be collected. Finally, airports with low overall ADF usage also requested EPA consider a de*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 19 of 147 minimis cut-off. They cited concerns that the costs of the collection and treatment for ADF at these airports are disproportionally high in rela tion to the amount of pollutants generated. For example, one commenter, a non-hub primary airport, explained that it typi cally receives little snow and conducts occasional defrosting of airc raft, and generates no ADF-contaminated water yet it would effectively be required to purchase a GCV if subject to the 20 percent collection requirement. EPA reviewed its data with respect to each of these comments. On further review of the data and comments, we now conclude that ADF us age in general is not closely related to the number of departures at airports alone. As such, in today’s final rule, EPA did not base the ADF collection and associated discharge requirement s on the number of departures. Instead, we decided to base the applicabilityof these requirements direct ly on estimates of the overall volume of ADF usage, which EPA indicated in the proposal was another possible threshold criterion for the rule (74 FR 44714). EPA reviewed its estimated costs for all the ADF collection and treatment scenarios evaluated for proposal, as a function of ADF usage and found that costs and impacts for airports using less than 60,000 gallons of normalized ADF annually were disproportionally higher than those with great er ADF usage. See DCN XXXX for additional details. As a result, in today’s final rule, EPA has established a cut- off of greater than or equal to 60,000 gallons of normalized ADF per deicing season. Those airports below this threshold are not subject to the final rule’s ADF collection/disc harge requirements, while those at or above this threshold are subject to these requirements. For the airports that are below this threshold, permit authorities will determine the technology-based limitations for aircraft deicing discharges in their NPDES permits on a case-by-case, be st professional judgment basis.*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 20 of 147 2. Collection Requirement Commenters also raised multiple concerns about the technology that EPA proposed to identify as BAT for the 60 percent collection requirement: centralized deicing pads. First, they raised concerns that CDPs are notfeasible at all locations becaus e of lack of space. Some of these commenters provided detailed engineering plans and analyses demonstrating their specific space constraints. Second, commenters raised concerns that using CDPs for all deicing operations would cause traffic and/ or safety problems. Third, co mmenters asserted that the use of CDPs would lead to flight delays and that EPA had not included costs associated with such delays in its analyses. In addi tion, FAA indicated that it had sim ilar concerns to those raised by industry commenters, regarding id entification of centralized deic ing facilities as BAT. FAA indicated that the 60 percent co llection requirement based on th e exclusive use of CDPs might adversely affect the operational efficiency of some of the nation's largest and busiest airports. Further, FAA was concerned that for those land- constrained airports, c onstruction and operation of centralized deicing pads for all deicing ope rations would not be ab le to meet FAA design standards. In explaining its co ncerns, FAA noted that delays a ssociated with the use of CDPs would be extremely costly to the nation's pr oductivity, economy, businesse s, and the traveling public. After considering these comments and reviewi ng the information in its record, EPA is not promulgating a 60 percent ADF collection require ment based on CDPs for BAT. First, in response to FAA’s concerns about the exclusive use of deicing pads for aircraft deicing, EPA contacted a number of large hub airports that cu rrently use CDPs. EPA found the current percentage of flights for which these airports use the CDPs range s from 50 to 95 percent. The airports explained that various operational or weather-related i ssues may make deicing pad use*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 21 of 147 for all flights cumbersome if not impossible, (i.e . severe system-wide dela ys), and require them to deice at the gate in some circumstances. EPA shares the commenters’ and FAA’s concerns that moving to exclusive use of CDPs for all deic ing might lead to operatio nal issues and delays. EPA, in discussions with FAA, attempted to craft regulatory provision s to allow an airport limited ability to bypass the use of a centralized pad in order to avoid these circumstances. However, limited data on the site-specific nature of this industry left EPA unable to develop regulatory provisions that would give airports th e flexibility they need to ensure efficient operations at airports. Second, based on public comments and inform ation from FAA since proposal, EPA is concerned that some large airports critical to e fficient air traffic operations in this country are space (land) constrained and that building well-located CDPs for all deicing operations at these airports is likely not feasible for that reason. At the time of the proposal, EPA estimated that 14 airports would be subject to the 60 percent coll ection requirement. Because the data in EPA’s record indicate that many of these airports currently meet this requirement, EPA estimated approximately seven airports would likely need to install pads as a result of the proposed requirement. Of these seven airports, four ar e large hubs which, over years of expansions and other improvements, have already built out the majo rity of the land available to them. EPA has concluded that the lack of rema ining available land, coupled with their existing layouts, has left these airports in a position where a CDP, conf orming to FAA’s Advisory Circulars on deicing pad design, (e.g., in a location that ai rcraft can travel to safely a nd efficiently to conduct deicing operations) cannot be constructed. Therefore, for today’s final rule, EPA has rejected a 60 percent ADF collection requirement based on identification of centralized deicing facilities as BAT for 100 percent of*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 22 of 147 aircraft departures because the technology is no t available at most airp orts and, therefore not technologically feasible. Because EPA has rejected a 60 percent re quirement in this final rule on the grounds that it is not technol ogically feasible, EP A did not do a detailed analysis of the commenters’ claims that signifi cantly increased economic costs a ssociated with flight delays would be expected to occur under a 60 percent collection requirement. B. New Source Definition and ADF Co llection Requirement Applicability In the proposed rule, “new source” would have included both new airports and new runways constructed at existing airports. Commen ters objected to the inclusion of new runways at existing airports in the new s ource definition. They noted that a new runway is not a source of pollutant discharges from aircraft deicing activit y and that a new runway is not “substantially independent” of an existing source as required unde r the regulatory definition of “new source.” See 40 CFR 122.2 and 40 CFR 122.29(b)(1). Comm enters acknowledge that a new runway may lead to additional discharges associated with ai rfield deicing, but noted that the requirements for airfield deicing discharges are the same for new and existing discharges. With respect to the requirements associated with discha rges from aircraft deicing, th ey explained that a new runway is not a source of new discharges because aircraft deicing is performed at locations away from airport runways. Moreover, they explained th at unlike a plant or factory from which a new source of discharge associated with a new proces s, production line, or piece of equipment can be clearly distinguished as a new s ource of discharge associated with an existing source, a new runway is not operated independently from other runways at an airport. Rather, a new runway and associated deicing operations are part of a who lly integrated airport syst em. In light of this new information, EPA agrees that under the cu rrent new source defini tion, new runways should*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 23 of 147 not be treated as new sources because new runways are generally too integral to the operations of an existing airport to be considered “substa ntially independent” of the existing airport. EPA has also revised the cut-off level of ADF usage that determines which new sources are subject to the ADF collection and discharge requirements. The proposal would have required ADF collection and associated discharge require ments for any new source with more than 10,000 annual jet departures. As was the case with existing sources, commenter s explained that the number of departures is not a good analog for the amount of ADF usage, citing, for example, airports in the south that may ha ve significant numbers of departur es but typically need to deice their aircraft only once a year. After reviewing these comments and the information in its record, EPA agrees that departures alone are not the mo st appropriate indicato r of ADF usage. As detailed in Section IV.A.2, for existing sources, to day’s final rule establishes a cut-off of greater than or equal to 60,000 gallons of normalized ADF per deicing season for the ADF collection and discharge requirements. Unlike existing sources, however, new sources do not have ADF usage data available—i.e., EPA ca nnot use past ADF usage to similarly inform a cut-off level for whether a new source is subject to NSPS requireme nts. Rather, in today’s final rule, as an indicator of the amount of ADF usage, EPA is basing NSPS applicability on whether the airport is located within specific colder climatic zone s (called here “heating degree day category”) as documented by the National Oceanic and Atmospheric Administration (NOAA). A “heating degree day” means the number of degrees per day the daily average temperature is below 65 degrees Fa hrenheit. The daily average temperature is the mean of the maximum and minimum temperature for a 24-hour period. The annual heating degree day value is derived by summing the daily heating degree days over a calendar year period. Heating degree days (HDD) are computed using data from the “U.S. National 1961-1990 Climate*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 24 of 147 Normals,” published by the National Climatic Data Center of NOAA. The original data are in whole degrees Fahrenheit. HDD values range from 0 to over 9,000. NOAA presents this information in 1,000-HDD increment groups. EP A used the NOAA information to create HDD groups. These groups range from A to I, with group A being the lowest HDD values (less than 1,000 HDD) and group I being the highe st (greater than 9,000 HDD). EPA identified the corresponding HDD group for ex isting airports and then compared the HDD group to ADF usage at each airport. In general, airports in HDD groups A through C (3,000 HDD or less) used less than 60,000 ga llons of ADF while those in HDD groups D through I used more than 60,000 gallons of ADF. As a result, these HDD groups provide a geographic dividing line nationwid e that corresponds we ll with the ADF usage dividing line for existing airports. EPA concludes that this approa ch best captures those new airports which will conduct more frequent deicing oper ations and excludes those new ai rports that expect to conduct infrequent deicing. See DCN XXX for EPA’s analysis of HDD categories. For the airports in the warmer climate locations that are excluded from the NSPS requirements in today’s final rule, permit write rs would determine an applicable new source performance standard on a case-by-case , best professional judgment basis. C. Extension of Applicability Date The applicability date of the final rule is 30 days following its pub lication in the Federal Register. However, the ADF co llection and discharge requirement s for existing dischargers are applicable three years following publication. S ee 40 CFR 449.1(b). EPA included this provision because it agrees with comments explaining th at airports are public entities that need considerable time to arrange both financing a nd construction for capital improvements to a facility associated with ADF coll ection and treatment. Furthermore, to the extent that airports*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 25 of 147 can obtain financing from FAA, FAA explained that its proce ss to obtain such funds would similarly require additional time. The extension of time for exis ting airports is necessary a nd appropriate because EPA has determined that the “best available technology” identified in this rulemaking for the ADF collection and discharge requirements, in many cas es, will not be an “available” technology upon the effective date of this rule (which is 30 days following publication). This is because many airport authorities need substantial additional time to carry out the steps for financing and capital improvements to implement these BAT technologies. However, the final rule provides that this extension of time is available only for the firs t three years af ter this rule’s promulgation. Existing airports that will be unde rgoing permit renewal past that date are able to use these first three years to plan and obtain financing such th at the BAT technology identified in this rule will be “available” to them at the tim e of their permit renewals. B ecause the technology basis for the airfield deicing discharges (pr oduct substitution) does not require large capital expenditures, it is available upon the effective date of the rule and an extension of time is not similarly appropriate. Because EPA has defined “new source” in today’ s final rule to include only new airports, EPA does not believe that new sources will require an extension of time as there are no new airport projects planned in the near future that would be subject to the ADF collection requirements in this final rule. EPA consulted with FAA about the potent ial for construction of new airports over the next several years. FAA stated that there are currently no plans for new airports to begin construction in the next several years. As a result, EPA concludes that any potential new airport will have ad equate time in its planning pro cess to incorporate today’s NSPS requirements, and as such would not require an extension in order to comply with any of the requirements of today’s rule. Th e technology that EPA has identif ied in this rule as “best*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 26 of 147 available demonstrated control technology” for new sources will be “available” for any and all new airports without the need for an extension of time. D. Deicing for Safe Taxiing The proposed rule included a provision th at would have exempted ADF-contaminated wastewater associated with deicing for safe ta xiing from the proposed collection and treatment requirement. EPA proposed to limit deicing for sa fe taxiing to 25 gallons of ADF, based on an allowance at Denver Internationa l Airport (DIA), as the maximu m amount that could be applied to an aircraft for the purposes of safe taxiing. This definition was intende d to apply to airports with CDPs, and to prohibit conducting complete deici ng of an aircraft at a terminal area without a collection system, instead of using the deici ng pad. However, commenters expressed concern that climatic conditions at airports in the Midw est, Alaska and on the East Coast differ greatly from those at DIA: they claim that any “deicing for safe taxiing” allowances established at DIA cannot form a reasonable basis fo r application to airports in ot her regions of the country. In addition, cargo aircraft sometimes experience layovers in excess of 24 hours, potentially increasing the amount of snow or ice that must be removed to achieve compliance with FAA regulations. EPA agrees with the commenters a nd as such, the final rule does not limit the amount of ADF sprayed for the purposes of safe taxi ing nor does the final rule require an airport to collect and treat ADF applie d for safe taxiing purposes. E. Glycol Collection Vehicles Although glycol collection vehicl es are currently used by at least 53 airports, commenters suggested that requiring some ai rports to use GCVs could affect operations and safety at those facilities. Commenters’ specific concerns abou t the increase in GCVs at and around the gate areas include affecting the ability of other ground support vehicles (baggage carts, fueling trucks,*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 27 of 147 etc.) to perform their duties and limiting the ability of aircraft to safely maneuver at the gates. However, the commenters provided no data to support these claims. Currently, many airports use GCVs with no apparent problems. More over, EPA observed GCV operations during its airport site visits and intervie wed airport personnel about operati onal practices and no one raised any safety or operational issues associated withuse of GCVs. EPA also consulted with FAA about potential operational and sa fety issues of today’s regulation, and FAA raised no concerns about EPA’s identification of GCVs as part of th e best available technolo gy for use by airports. Therefore, EPA believes that the use of GCVs will not affect operations or safety of an aircraft or aircraft-related operations in gate areas. F. Effluent Limitation fo r Chemical Oxygen Demand EPA received comments questioning the Agency’s use of chemical oxygen demand (COD) as an effluent limitation parameter. Specific comments include questions on whether EPA’s rationale for using COD as opposed to BOD 5 as an indicator pollutant for glycol was reasonable, and whether the agency intended to set a limit for COD or soluble COD. 1. COD as an Indicator for ADF Some commenters raised issues on EP A’s selection of COD instead of BOD 5 as an indicator parameter. Others, such as the Phila delphia Airport, agreed with EPA’s selection. Specific comments against EPA’s selection includ e: EPA’s rationale of why COD is a better indicator parameter is not accurate, COD does not adequately reflect the dissolved oxygen available for treatment in a biological treatmen t system, and there is an implied Congressional mandate to address BOD 5 . Each of these is discussed in more detail below. EPA presented four reasons in the proposed rule as to why it selected COD as the indicator pollutant for ADF discharges:*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 28 of 147  While both BOD 5 and COD parameters are good indi cators of the glycol-based oxygen demand component of deici ng stormwater, COD will also capture the oxygen demand from nitrogen and other organic component s of the stormwater that may not be represented in a BOD 5 result.

 COD analyses are simple to conduct and can be measured in real time, compared to the 5-day test required by the BOD 5 analytical method.

 COD eliminates the need to consider receiv ing water temperature when evaluating water quality concerns.

 Toxic ADF additive compounds in deicing stor mwater may have a negative and variable affect on the acclimation of the active culture s used in BOD analysis, making the method less robust than COD analys is for these wastewaters. Trade association comments in response ar gued that EPA had not proven that COD will also capture the oxygen demand from nitrogen and other organic components of the stormwater. Furthermore, they argue nitrogen is not associated with ADF and is being regulated separately as part of the airfield deicing stormwater requirements. EPA agrees that nitrogen is not associated with ADF discharges and that it is addressing nitrogen concerns a ssociated with airfield deicing discharges (specifically the ge neration of ammonia from urea degradation) primarily through regulation of ammonia as N. As such, the prim ary purpose of the COD indicator pollutant is to address organic components of ai rcraft deicing discharges, some of which are not captured with
a BOD 5 analysis. It is widely accepted that COD measures pollutants that are not measured by BOD 5 . The ratio of COD to BOD 5 for most industrial wastewater typically ranges from 1.5 to 2.0. As explained in Section xx of the TDD, EPA doe s not have information on all of the exact*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 29 of 147 constituents in aircraft deicing fluid. Without these data, it is not possible for EPA to determine the chemicals measured by COD that would not be captured by a BOD 5 analysis. However, samples of ADF-contaminated wastewater show a similar trend to typica l industrial wastewater (i.e., COD concentrations are higher than BOD 5 concentrations), indicating that ADF has oxygen-demanding additives that are not measured by a BOD 5 analysis. Therefore EPA has determined that the most robust and accurate manner of documenting the oxygen demand associated with ADF is to use the more inclusive oxygen dema nd indicator, COD. Commenters also argued that COD measur ement in “real time” versus the five days required for the BOD 5 test was not a valid reason for selec tion of COD as the regulated pollutant. EPA disagrees and concludes that this is a hi ghly significant reason for selecting COD as the appropriate pollutant for regulation. Because COD can be measured more quickly and accurately, it allows a treatment operator more ab ility to ensure optimal and reliable operation than the BOD 5 test would allow. Data provided by the industry and a manufacturer of an AFB system demonstrate that it is i ndustry practice to eval uate treatment effectiveness and system control by measuring the C OD of the system effluent. Specifica lly, the record demonstrates that industry uses COD because the BOD 5 analyses requires five days to obtain a result and does not enable a system operator to obtain invaluable fee dback to evaluate treatment system control and effectiveness in real time allowing for optimal treatment system operation. (The use of COD in place of BOD 5 is also used to optimize and evaluate biological treatment of other industrial wastewaters and is widely recommended in wastewater treatment references.) Real-time feedback through use of the COD parameter is particularly important for optimal treatment and control of ADF wastewaters in this rulemaking, compared to other effluent limitation guidelines. Most ELGs for other industrial categories with BOD 5 limitations limit*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 30 of 147 individual constituents in addition to BOD 5 . In such cases, most facilities have on site laboratories that provide the capabil ity to measure those constituents in real time. As a result, treatment operators use the data from the individual constituents to monitor and adjust the operation of their treatment system in real time to ensure optimal treatment. In contrast, in today’s final regulations for ADF , there are no limits being set fo r individual constituents in the waste stream. Consequently, there will be no data from monitoring of individual constituents on which to base real-time adjustments to the treatment system. Instead, to make such real-time adjustments, under today’s rule, operators wi ll be able to rely on COD measurements. In addition, EPA notes that the commente rs’ remarks concerni ng consideration of receiving water temperature when evalua ting water quality concerns using a BOD 5 value vs. COD are irrelevant. EPA agrees that organic compounds like glyc ol might degrade at a slower rate in cold receiving waters; however, effluent limits are not established based on receiving water temperature, but on treatment system pe rformance. For example, secondary treatment effluent limitations for BOD 5 from publicly owned treatment works are established on treatment system performance, and compliance with the BOD 5 limitation requires the POTW to measure
BOD 5 using an approved analytical method. That method requires sample analysis be conducted
at 20 o C, regardless of the receiving water temper ature. Therefore establishing an effluent limitation based on COD or BOD 5 is appropriate for the airport deicing rule because receiving water temperature is not a factor in analyt ical methods used to determine compliance. Finally, commenters argued that use of BOD 5 instead of COD is appropriate because any effect of toxicity on BOD testing can be account ed for through proper analysis. EPA disagrees that the BOD 5 and COD tests are equally appropriate in this regard. In ev aluating pollutants of concern for aircraft deicing-re lated stormwater, EPA noted thatthere are additives to ADF,*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 31 of 147 which may exert toxicity above that caused by the oxygen demand of the glycol components of these fluids. Until the effects of these a dditive compounds are further understood, EPA maintains that their presence in deicing st ormwater (which was confirmed through EPA’s sampling efforts) may cause negative and vari able affects on the acclimation of the active cultures used in BOD analysis. This i ssue is not a factor for COD analysis. 2. Arguments that EPA Must Address BOD 5 Commenters argued that EPA impermissibly selected COD as the regulated pollutant and should have selected BOD inst ead. As asserted by one comm enter, by designating COD (a nonconventional pollutant) as the “r egulated pollutant,” and thendeveloping a proposal only at the BAT level, EPA has avoided the need to char acterize the levels of tr eatment that would be needed if EPA were regulating BOD 5 , which is a conventional pollutant – i.e., EPA has avoided the cost tests applicable to BPT and the two-part cost sensitivity analysis that is required for a BCT analysis. It believes that EPA’s decision th at COD is the appropria te regulated pollutant rather than BOD 5 , “facilitates the imposition of BAT, whic h is potentially much more stringent and costly than BPT or BCT.” (DCN xxx [ATA, Docket #1226], p. 167) In response, EPA has discretion to determine what pollutant parameters are appropriate to regulate as pollutants of concern in an effluent guideline. See, e.g., National Wildlife Federation
v. EPA , 286 F.3d 554 (D.C. Cir. 2002) (EPA had discreti on not to regulate color as a pollutant of concern). Chemical oxygen demand is a pollutant in and of itself. See BASF Wyandotte Corp. v. Costle, 598 F.2d 637, 651 (1 st Cir. 1979). The CWA defines pollutant broadly to include “dredged spoil, solid waste, incinerator resi due, sewage, garbage, sewage sludge, munitions, chemical wastes, biological materials, heat, wr ecked or discarded equipment, rock, sand, cellar dirt and industrial, municipal and agricultural waste” (CWA sec tion 502(6)). See NRDC v. EPA ,*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 32 of 147 822 F.2d 104, 109 (D.C. Cir. 1987)(“The term ‘polluta nt’ is broadly defined . . .”); U.S. v. Hammel, 551 F.2d 107, 110 (6 th Cir. 1977)(noting that the defi nition is set forth in “broad generic terms”). COD is a chemical measure of the oxygen requirement to oxidize the organic matter in water. COD, like BOD or pH, wh ich are expressly mentioned as conventional pollutants in CWA section 304(a)(4) and 40 CFR 401.16, easily fits that definition. The definition of pollutant is not limited to those term s that are specifically lis ted in the statute at section 502(6). See NWF v. Gorsuch, 693 F.3d 156, 174 n. 56 (D.C. Cir. 1982); Sierra Club v. Cedar Point Oil Co., 73 F.3d 546, 565 (5 th Cir. 1996). Thus, COD is a pollutant under the Act, and EPA has described above the comprehensive r easons for why it determined that COD is the appropriate pollutant on which to set effluent limitations in this rule rather than BOD 5 . An additional reason why it is appropriate to se t limits in this rule based on COD is that, apart from the biodegradable oxygen-demanding or ganic containing polluta nts, the wastestream from aircraft deicing operations also contains certain non-conven tional pollutants that may not be measured in a BOD 5 analysis. Even if EPA were to set BPT/BCT limits for the oxygendemanding pollutants on the basis of BOD 5 , we would still be require d to promulgate the BAT limits in this final rule in order to control the non-conventio nal pollutants that may not be measured by the BOD 5 analysis. Any BPT/BCT established for BOD 5 would be equal to or less stringent than the BAT limits th at would be set for these other non-conventionals. Because the BAT limits would be controlling, any addi tional BPT/BCT limits established for BOD 5 would therefore be superfluous. Aircraft deicing fluid contains not only biodegradable oxygen-demanding pollutants but also chemical additives which, under the CWA, are toxic or non-conventional pollutants. Additionally, stormwater discharges from airports in their entirety are “industrial waste,” a*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 33 of 147 nonconventional pollutant under th e CWA (see, e.g., Reynolds v. Rick's Mushroom Service,
Inc. , 246 F.Supp.2d 449, 455 (E.D. Pa. 2003) (rainwat er contaminated by industrial waste constitutes a pollutant). EPA is not required to single out specific constit uents or parameters in the discharge. See Northern Plains Resource Council v. Fidelity Exploration and Development
Co . 325 F.3d 1155 (9 th Cir. 2003). The appropriate level of control under the CWA for these nonconventional pollutants is BAT. See CWA se ction 301(b)(2)(A) and (F). Similarly, the appropriate level of control unde r the CWA for all pollutants from new sources is best available demonstrated control technology (BADCT). See CWA section 306. Where the same wastestream contains bot h conventional pollutants (such as BOD 5 ) and toxic and non-conventional pollutants, it is reasonable to limit the rule to BAT limits (and BADCT standards for new sources) because these controls would supersede any less stringent limits under BPT or BCT. The first component of the BAT technology in this final rule is a collection requirement, requiring in-s cope airports to collect 40 percent of available ADF after it is applied to aircraft. Even if the oxygen-demanding pollutant in ADF were considered to be a conventional pollutant (BOD 5 ), the ADF contaminated stormwat er that is collected contains other non-conventional pollutants, as described ab ove. The final rule thus would contain, under any scenario, a BAT requirement of 40 per cent collection to cont rol these other nonconventionals. This 40 percent co llection requirement would be controlling even if EPA were to determine that the criteria for BPT/BCT would re sult in a less stringent collection requirement for conventional pollutants in the discharge. Co llection is done once, and obviously will capture whatever pollutants are in the discharge; it is not possible to have different collection requirements for different pollutants in the discharge.*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 34 of 147 The second component of BAT identified in this final rule is based on treatment of the collected ADF contaminated stormwater by an an aerobic fluidized bed treatment system. Again, based on the presence of the non-conventional po llutants alone, the final rule would require treatment of all the co llected ADF through an AFB treatment system. Doing so would treat any conventional pollutants such as BOD 5 in the wastestream as well. In sum, both the collection and treatment components of BAT in today’s rule will apply to the entire wastestream, based on the non-conventional pollutants in the wastestr eam alone. Those collection and treatment requirements would be controlling even if there were other conventional pollutants contained in the wastestream as well, such as BOD 5 . 3. COD Versus Soluble COD as a Regulated Pollutant EPA proposed to establish a numeric limit for COD for direct discharges of collected ADF based on anaerobic fluidized bed treatment. EPA calculated the proposed COD limit from long term sampling data from Albany Airport. EPA received comments in support of its use of Albany sampling data for setting the numeric limit. However, commenters correctly noted that while EPA proposed to establish a COD limit, Al bany filtered its sample prior to analyzing for soluble COD. Moreover, commenters stated that setting a COD limit based on soluble COD data is inappropriate because COD measurements wo uld likely be higher than the proposed limit. EPA agrees with the commenters that the Al bany data upon which it developed the proposed limit reflects COD that is filtered. As a result, to day’s final rule includes a sampling protocol for airports to filter compliance samples prior to analysis for COD.

V. Scope and Applicability of the Final Rule*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 35 of 147 This final rule applies to primary airports with discharges from deicing operations. The applicability is further narrowe d in the provisions on BAT and N SPS, to airports with greater than or equal to 1,000 annual departures by non-propeller-driven airc raft. The ammonia discharge provisions (concerning runway de icing), § 449.10(b) for BAT and § 449.11(b) for NSPS, apply to all such airports. In addition, existing in-scope airports that use ADF at an annual rate of 60,000 gallons or more (normaliz ed) are subject to th e BAT collection and discharge requirements, as applicable at § 449.10(b) and (c). New source ai rports located in an area with more than 3,000 annual heating degr ee days are subject to NSPS collection and discharge requirements, as applicable at § 449.11(a) and (b) (see discussion above). A new airport with deicing discharges, that is initially ope rating less than 1,000 nonpropeller aircraft departures a nnually is not initially subject to the NSPS provisions in §449.11. However, if the number of departures later incr eases above that thres hold, then §449.11 becomes applicable. This means that a new airport that expects to eventually ex ceed the 1,000 departure threshold must plan to install and operate facili ties that comply with the requirements of that section.

A. Subcategorization EPA may divide a point source category into groupings called "subcat egories" to provide a method for addressing variations among products, processes, and ot her factors, which result in distinctly different effluent characteristic s. See Texas Oil & Gas Ass'n. v. US EPA , 161 F.3d 923, 939-40 (5th Cir. 1998). Regulation of a category by subcategories provides that each subcategory has a uniform set of effluent limitations that takes into account technological achievability and economic impacts unique to th at subcategory. In some cases, effluent*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 36 of 147 limitations within a subcategory may be different based on consideration of these same factors, which are identified in CWA s ection 304(b)(2)(B). The CWA requires EPA, in developing effluent guidelines, to consider a number of di fferent factors, which are also relevant for subcategorization. The CWA also authorizes EP A to take into account other factors that the Agency deems appropriate. In developing today’s rule, EPA consid ered whether subcategorizing the aviation industry was warranted. In addi tion to those factors specified in the CWA, EPA evaluated a number of factors and potential subcategorization approaches, in cluding the presence of an onsite glycol reclamation facility, amount of ADF applied, number of departures, availability of land to install collection systems, and FAA ai rport classifications. EPA concluded that establishing formal subcategories is not neces sary for the Airport Deicing category. EPA structured the applicability and re quirements of the final rule to account for the relevant factors (e.g., amount of ADF applied) and has established a set of requirements appropriate for the range of situations that an airpor t may encounter during deicing op erations. Commenters suggested there should be a separate sub category for land-constrained air ports, however now that EPA has determined that CDPs are not the basis for BAT, there is no longer a need for a formal subcategory. B. Industry Description The Airport and Airway Improvement Ac t (AAIA), 49 U.S.C. Chapter 471, defines airports by categories of air port activities, including Commerci al Service (Primary and NonPrimary), Cargo Service, and Reliever. These cat egories are not mutually exclusive; an airport may be classified in more than one of these categories. Another gr oup of generally smaller*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 37 of 147 airports, not specifically define d by AAIA, is commonly known as "general aviation" airports. EPA estimates that there are approxima tely 500 commercial service airports. Commercial service airports are publiclyowned airports that have at least 2,500 passenger boardings each calendar year and rece ive scheduled passenger service. Passenger boardings refer to revenue passenger boardings on an aircraft in service in air commerce, whether or not in scheduled service. The defin ition also includes passengers who continue on an aircraft in interna tional flight that stops at an airport in any of th e 50 States for a non-traffic purpose, such as refueling or aircraft mainte nance rather than passenger activity. Passenger boardings at airports that receive scheduled passenger service are also referred to as "enplanements." Primary commercial service airports (primary airports) have mo re than 10,000 passenger boardings each year. Primary airports are fu rther subdivided into Large Hub, Medium Hub, Small Hub and Non-Hub classifications, based on the percentage of total passenger boardings within the United States in the most current cale ndar year ending before th e start of the current fiscal year. Early in the regulatory development proce ss, EPA focused on deicing activities at primary airports, particularly t hose with extensive non-propeller tr affic. Operators of general aviation aircraft, as well as sm aller commercial non-jet aircraft , typically suspend flights during icing conditions, whereas commercial airlines oper ating at primary airports are much more likely to deice their jets in order to meet customer demands. Based on the results of surveys of the indus try that EPA conducted prior to the proposed rule, the Agency estimated that 320 primary airp orts conduct deicing operations. EPA reviewed the relative sizes of various airports (based on annual departures), the le vels of deicing activity,*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 38 of 147 traffic characteristics (i.e. passe nger vs. cargo operations), the ex tent of pollution controls and treatment in place, and the costs of various t echnologies for these airports. EPA further classified airports based on the number of annual non-propeller departures. EPA found that there were some primary airports, typically smaller airports, with high per centages of non-propeller aircraft, and so it excluded air ports with fewer than 1,000 annual non-propeller departures from the scope of the proposed rule. These airpor ts have a higher proporti on of propeller-aircraft flights, which are typically delayed or cancelle d during icing conditions (i.e. far less deicing takes place at these airports, and far less deicing fluid is used, than at airports se rving more jets). C. Wastewater Sources and Wastewater Characteristics 1. Aircraft Deicing Airlines apply most ADF to aircraft through pressurizedspraying systems, mounted either on trucks that move around an aircraft, or on large fixe d boom devices located at a pad dedicated to deicing. Most of the aircraft deicing fluid sprayed is Type I fluid, which is designed for minimal adhesion to aircraft surfaces. Consequently the majority of Type I ADF is available for discharge due to dripping, over-s praying, tires rolling through or sprayed with fluid, and shearing during takeoff. Once the ADF has reached the ground, it will then mix with precipitation, as well as other chemicals found on airport surfaces. (These chemicals typi cally include aircraft fuel, lubricants and solvents, and metals from aircraft, ground support and utility vehicles.) Water containing these substances enters an airp ort's storm drain system. At many airports, the storm drains discharge directly to waters of the United States with no treatment.*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 39 of 147 Type IV fluid, an anti-icing chemical, is design ed to adhere to the aircraft. Because of this adherence characteristic, EPA estimated that th e majority of Type IV fluid is not available for collection. For the purposes of this rule, the pollutant lo adings are discussed in terms of applied ADF and how much of that is expect ed to be discharged. A more detailed discussion of loadings estimates is presented in Section VII.B below. Gi ven the highly variable nature of storm events, it is difficult to estimate flows or concentratio ns of ADF-contaminated stormwater generated at an airport. Those factors are gr eatly dependent on site specific factors such as the size of the storm event associated with the discharge, drai nage characteristics, ADF collection systems (if present), and airport operations. Additionally, due to the design of drainage systems at some airports, their discharges may occur we ll after a storm event has completed. 2. Airfield Pavement Deicing Most solid airfield deicing chemical pr oducts are composed of an active deicing ingredient (e.g., potassium acetate, sodium acet ate) and a small amount of additives (e.g., corrosion inhibitors). Liquid ai rfield deicing chemical products are composed of an active ingredient (e.g., potassium acetate, propylene glycol), water, and minimal additives. The airfield deicing products that include salts (i.e., potassi um acetate, sodium acetate, and sodium formate) will all ionize in water, creating positive salt ions (K + , Na + ), BOD 5 and COD load as the acetate or formate ion degrades into carbon dioxide (CO 2 ) and water. Pavement deicers containing urea will degrade to ammonia, and generate BOD 5 and COD load as well. Most of EPA’s deicing characterization data do es not reflect airfield pavement deicers. However, EPA collected samples from a few loca tions at Detroit Metro Airport that contain airfield deicing stormwater. Large hub airports, both Detroit Metro and Pittsburgh, provided*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 40 of 147 sampling data associated with stormwater contam inated by airfield pavement deicers. More information on these sampling activities is provided in the TDD. As with the aircraft deicers, the variability of storm events and drainage syst ems makes it difficult to estimate flows or concentrations of pavement deicing wast e streams generated at an airport. D. Control and Treatment Technol ogies for the Aviation Industry The ADF application process has presented a challenge for airports attempting to manage their contaminated stormwater streams. The process of applying ADF to aircraft through high pressure spraying, combined with the typical pr actices of spraying the aircraft outdoors in multiple, large unconfined (but usually designated) spaces, results in pollutants being dispersed over a wide area and entering storm drains at multip le locations. This process contrasts sharply with many other industries where pollutants are ge nerated in confined areas, managed through a piping system, and not commi ngled with precipitation. EPA has identified several technologies that are available to collect and manage portions of the ADF wastestream. Some of these collecti on technologies are more effective than others. However, no single technology is capable of collec ting all applied ADF, as a portion of the fluid is designed to adhere to the aircraft until after takeoff, to ensure safe operations. Furthermore, with few exceptions, tracking by aircraft tires, wind dispersion, and drip ping during taxiing and takeoff ensures that some amount of sprayed ADF, even if performed in a contained area, will end up in the drainage system of the airport. For these reasons EPA concludes that all airports that perform aircraft deicing ope rations are direct di schargers. (There are limited instances where an airport in a warm climate that pe rforms only defrosting and gets little to no precipitation may, in fact, not di scharge any deicing materials.)*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 41 of 147 Once the available ADF wastestream is collect ed, it can be treated, and this process is similar to many other industries th at generate wastewater. In a similar manner, airfield deicing has presented a challenge for airports attempting to manage their contaminated stormwater streams. Airfield deicing is typically conducted over a large area, includi ng areas with frequent aircraft traffic, such as runways, where active collection technologies (i.e . GCVs) are impractical to implement. At this time, EPA has not identified any available economically achievable technologies for the collection of pavement deici ng stormwater. As a result, EPA also examined pollution prevention technologies, which can reduce or eliminate use of ADF chemicals and urea containing deicers for pavement deicing in today’s final rule. The following section discusses the technologi es EPA considered for ADF collection and treatment and for addres sing airfield deicing. 1. Aircraft Deicing Flui d Collection Technologies a. Glycol Collection Vehicle. A glycol collection vehicle (GCV) is a truck that utilizes a vacuum mechanism to gather stormwater contaminated with ADF resulting fr om deicing operations. GCVs are typically stationed near the ADF spraying tr ucks and are deployed either dur ing aircraft deicing activitiesor, after the aircraft deicing activity has completed. The GCV then transports the ADFcontaminated stormwater to an on-site storag e and/or equalization facility, after which the material is either treated at the airport or sent off site for trea tment. EPA estimates that GCVs typically collect at least 20 percent of the avai lable ADF when properly operated and maintained. b. Plug and Pump The plug-and-pump collection system utilizes an airport’s existing storm water collection system infrastructure to contain and collect ADF contaminated stormwater. Plug and pump*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 42 of 147 systems also commonly utilize GCVs for ancill ary ADF collection. Typical GCV deployment may include collecting ADF that has been sp rayed beyond the plug and pump containment area or as an additional collection measure at the gate , ramp and/or apron area after deicing operations and active plug and pump collection has ceased. The plug and pump system operates by placing either temporary inflatable balloons or storm se wer shutoff valves in the existing storm sewer system. During deicing events, the balloons are inflated and storm sewer shutoff valves are closed, trapping the ADF-contaminated stormwater in the collection system. Vacuum trucks pump the trapped contaminated stormwater from the storm sewer system and transport the liquid to on-site storage and/or equalization. In a ddition, catch basin insert s can be placed into manholes to collect ADF-contaminated stormwater. c. Centralized Deicing Pads A centralized deicing pad is a paved area on an airfield built speci fically for aircraft deicing operations. It is typically located ad jacent to a gate area, taxiway, or runway, and constructed with a drainage system separate from the airport's main storm drain system. It is usually constructed of concrete with sealed joints to prevent the loss of sprayed ADF through the joints. The pad's collection system is typically connected to a wastewater storage facility, which then may send the wastewater to an on- site or off-site treatment facility. Some airports use GCVs in combination with CDPs to collect ADF that lands outside the pad collection area in order to maximize coll ection and containment of ADF-contaminated stormwater. Airports typically loca te the pads near the gate areas or at the threshold of a runway to minimize delays in aircraft takeoff and to enhance the effectiveness of the ADF applied by limiting time between application and takeoff.*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 43 of 147 CDPs reduce the volume of deicing wastewater by restricting deicing to small areas, and managing the collected wastewater through a dedicat ed drain system. EPA estimates that CDPs allow airports to collect at leas t 60 percent of the available ADF. d. Summary of ADF Collection Technology Usage EPA estimates the number of airports that use each of the above collection technologies in Table V-1. Some airports use more than one technology, and some of the airports in the estimate use the technology for only a portion of their ADF-contaminated stormwater.
Table V-1. Estimated Totals of ADF Collection Technologies Used by Airports Collection Technology Number of Airports Glycol Collection Vehicle 53 Plug and Pump 29 Centralized Deicing Pad 66

See section 8.2 of the Technical Development Document for further explanation of EPA’s estimates of the ADF collection rates for the fluid collection technologies. 2. ADF-Contaminated Wastewat er Treatment Technologies In the proposed rule EPA identified four technologies for treating ADF-contaminated wastewater: Anaerobic Fluidized Bed (AFB), U ltrafiltration/Reverse Osmosis, Mechanical Vapor Recompression and Distillation, and Aera ted Pond. The Agency selected AFB and rejected the other technologies . See 74 FR 44687 and the TDD. An AFB treatment system uses a vertical, cylindrical tank in which the ADFcontaminated stormwater is pumped upwards th rough a bed of granular activated carbon at a velocity sufficient to fluidize, or suspend, the media. A thin film of microorganisms grows on and coats each granular activat ed carbon particle, providing a va st surface area for biological*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 44 of 147 growth. These microorganisms provide treatme nt of the ADF-contaminated stormwater. Byproducts from the AFB treatment system in clude methane, carbon dioxide and new biomass (animal material, e.g. bacteria). The AFB treatment system includes storage as an initial step to equalize flows and pollutant concentrations th at feed into the biol ogical treatment unit. Treating wastes using an anaer obic biological system as comp ared to an aerobic system offers several advantages. The anaerobic system requires much less energy since aeration is not required and the anaerobic system produces less than 10 percent of the sludge of an aerobic process. In addition, because th e biological process is containe d in a sealed reactor, odors are eliminated. Based on EPA sampling results, th e AFB treatment system successfully removes over 98 percent of BOD 5 , over 97 percent of COD, and over 99 percent of propylene glycol from deicing wastestreams. This reduces the BOD 5 and COD loads discharged to receiving waters by over 98 and 97 percent, respectivel y. Two airports in the United States use the AFB technology: Albany International Airport in Albany, New Yo rk, and Akron-Canton Regional Airport, Akron, Ohio. Additionally, Portland International Air port (Oregon) recently installed an AFB system and T.F. Green Airport (Providence, RI) is planning installation of this technology. 3. Pollution Prevention Technologies EPA has identified several technologies that may reduce ADF usage, that are in use at airports across the United States. The following section describes the ma jor pollution prevention approaches EPA identified during this rulemaking. However, there are limited data on the actual pollutant reductions that these t echnologies may achieve. In add ition, the airports that use these technologies only use them on a limited basis. As a result, they are not currently demonstrated to be widely feasible and/or available technology and EPA did not consider them as a basis for BAT or NSPS in today’s final rule. If thes e technologies are proven to be available and*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 45 of 147 effective, they have the ability to eliminate or reduce ADF applic ation. The ability to reduce the amount of applied deicing chemicals will not onlyhave a positive environmental effect, but may also be cost-effective, as the decreases in cost s of purchased deicing chemicals may offset the cost of the technology itself. EPA applauds all efforts to develop deici ng chemicals and approaches that reduce or eliminate pollutant discharges. In order to ensure that this rule doesn’t prevent such approaches as they become proven, feasible, and available, today’s final rule include s a provision to apply a pollution prevention credit against the standard ADF collection requirement. See Section XI.C., Demonstrating Compliance with the ADF Co llection Requirement, in this preamble. a. Infrared Deicing Systems A few U.S. airports have used infrared (IR ) heating systems for se veral years and these systems have been demonstrated to deice aircraft effectively. One type of IR system consists of an open-ended hangar-type structure with IR generators mounted inside, suspended from the ceiling. The IR equipment is designed to use spec ific wavelengths that heat ice and snow, and minimize heating of aircraft components. The IR energy level and wavelength may be adjusted to suit the type of aircraft. A lthough the system can deice an airc raft, it cannot provide aircraft with anti-icing protection. Consequently, when the ambient temperature is below freezing, antiicing fluid is typically applied to the aircraft after it leaves the hangar. In addition, a small amount of deicing fluid may be required for deici ng areas of the aircraft not reached by the IR radiation, such as the flap track s and elevators. The system, th erefore, does not completely replace glycol-based fluids, but may greatly reduce th e volume required.*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 46 of 147 Vendors claim use of an IR system reduces the amount of Type I ADF required by up to 90 percent. John F. Kennedy Inte rnational Airport, New York, uses an IR system for a small percentage of its flights. b. Forced Air/Hot Air Deicing Systems Forced air/hot air deicing systems are currently in operation at a few U.S. airports. These systems use forced air to blow snow and ice from aircraft surfaces. Some systems allow deicing fluids to be added to the forcedair stream at different flow settings (e.g., 9 and 20 gpm), while other systems require separate application of deicing fluid. Several vendors are currently developing self-contained, truck-mount ed versions of these forced-a ir systems, and most systems can be retrofitted onto existing deicing trucks. A similar method to truck-mounted forced-a ir systems is the double gantry forced-air spray system. The gantries support a set of high- and low-pressure nozzles, which blast the aircraft surfaces with heated air at a pressure of 40 to 500 pounds per square inch. When weather conditions are severe, a sm all volume of water and glycol ma y be added to the air stream to remove dense coverings of snow and ice. Ai rfield use of the gantrysystem has been limited perhaps because it is a permanently mounted system that has been known to cause delays in aircraft departures. c. Product Substitution Another solution to environmental problems associated with deicing chemicals is to replace chemical deicers with more environm ent-friendly products. In the ADF products category, initially the predominan t deicers were based on ethyle ne glycol, whereas in recent years propylene glycol-based deicers, which are less toxic to mammals, have become more widely used. Chemical manu facturers, the aviation industr y and the U.S. Air Force are*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 47 of 147 continuing to explore development of deicers th at could generate lower levels of pollutants compared to the glycol-based products. 4. Airfield Pavement Deicing Control Technologies EPA identified product substitution as an available control technology for airfield pavement deicing chemicals. The Agency did not identify an available economically achievable technology to collect and treat pavement deicing pollutants. Several types of products are available as alternatives to pavement deicers containing urea, such as potassium acetate, sodium format e and sodium acetate. The results from EPA’s airport questionnaire reported that eighty-three percent of primary airports use airfield pavement deicers that do not contain urea. The most widely used substi tute product, potassium acetate, accounts for 63 percent (by weight) of the annual ai rfield pavement deicer usage in the U.S. E. Regulated Pollutants EPA identified 31 pollutants of concern th at stem directly from airport deicing operations. In today’s rule, EPA is establ ishing discharge limitations for collected ADF contaminated stormwater for COD only and re quiring product substitutio n (or, alternatively, meeting an ammonia limit) to redu ce ammonia discharges associated with airfield deicing. See Section 6 of the Final Technica l Development Document for a fu ll discussion of pollutants of concern and EPA’s rationale for selecting regulat ed pollutants. VI. Final Regulation A. BPT and BCT EPA considered whether in this rule, it was necessary to establish BPT limits, given that ADF and pavement deicers will be controlled at the no less stringent BAT level. Because the BAT controls in this rule also result in the coll ection and treatment of glycol at the same level as*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 48 of 147 would be established in BPT limits, it is not ne cessary for EPA to promulgate BPT effluent limitation guidelines for the Airport Deicing Ca tegory. Additionally, EPA is not establishing BCT limitations for this industry because these limitations apply only to conventional pollutants such as BOD 5 and total suspended solids, and for the other reasons set forth in the related discussion above at Section IV.F, Effluent Limitation for Chemical Oxygen Demand.
B. BAT For airfield deicing (runways), EPA concl udes that the “best available technology” for reducing ammonia in wastewater discharges consists of the use of deicing products not containing urea, instead of deici ng products that contain urea. The record shows that products without urea are widely available in the industry, and in fact are already in use at a majority of airports across the country. In addition, using only deicers without urea is economically achievable by the industry, as explained in the discussion of EPA’s economic analysis below. To comply with this limitation, a discharger subject to the rule must either certify annually that it does not use airf ield deicing products that cont ain urea or airfield pavement discharges must achieve a numeric limitation for ammonia as nitrog en of 14.7 mg/L. In addition, with respect to ai rcraft deicing, for a subset of airports subject to the rule (with average annual normalized ADF usage as described in 40 CFR 122.21(s)(1) of 60,000 gallons or greater as calculated over the previ ous five deicing seasons), the rule also requires ADF collection of 40 percent of available ADF and treatment of collected ADF prior to direct discharge to meet a numerical effluent limitation for COD. 1. Airfield Deicing: Product Substitution of Pavement Deicers Containing Urea In general, airports discharg e airfield pavement deicing ch emicals without treatment, due to the difficulty and expense required in collecting and treating the large volumes of*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 49 of 147 contaminated stormwater generate d on paved airfield surfaces. EPA is not aware of an available, economically achievable means for controlling th ese pollutants through co llection and use of a conventional, end-of-pipe treatment system. It is possible, however, to reduce or eliminate certain pollutants by modifying deicing practices, such as using alternative chemical deicing products. In particular, EPA ha s identified ammonia as the prim ary pollutant of concern from airfield deicing, while COD from ai rfield deicing is also a pollutant of concern, and both of these pollutants are a byproduct of pavement deicer s containing urea. Accordingly, to address discharges of ammonia from airfield pavement, EPA identified one candidate for best available technology, namely, product substitution, or di scontinuing the use of pavement deicers containing urea and using alternative pavement deicers instead. EPA found that the use of deicers without urea is the best available technology for reducing discharges of ammonia from pavement deicing because it is safe, technologically feasible and availabl e across the industry, it does not produce discharges of ammonia as ar e produced by deicers cont aining urea, and it is economically achievable for all airports. Curren tly only about 10 percent of chemical pavement deicers applied nationwide contain urea. The most widely used pavement deicer is potassium acetate, 63 percent of all chemical paveme nt deicers, and is used nationwide. Under the final rule, this requirement is implemented through one of tw o ways: (1) any discharger subject to this part must certify annually that it does not use airfield deicing products that contain urea, or (2) airfie ld pavement discharges at all locations where pavement deicers contain urea must achieve the numeric limitation of 14.7 mg/L for ammonia prior to any dilution or commingling with no n-deicing stormwater. This numeric limit is based on the ammonia generated by the BAT technology for treating aircraft deicing wastewater. EPA expects that most dischargers will select a certification*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 50 of 147 route to comply with this limit. However, if airports choose not to so certify, EPA is providing a numeric limitation as an alternative complian ce mechanism. EPA chose to use the ammonia levels discharged from the AFB treatment system as the basis for setting the numeric limit to ensure that no inadvertent exceedances of the limit occur from ammonia generated by the AFB treatment system, in cases where the effluent from AFB treatment is discharged through the same outfalls as are used for discharges from runw ays. Information in the record for today's rule indicates that discharges from airports not using pavement deicers containing urea are well below the promulgated numeric limit for ammoni a. Airports provided data to EPA on outfall concentrations of ammonia associated with pave ments treated with deicers not containing urea. These concentrations are below the pr omulgated numeric limit for ammonia. While EPA is unaware of a method to collectand treat all pavement deicer containing stormwater, some industry commenters stated, but provided no data to support, that deicers containing urea are more effective at than non-urea deicers at lo wer temperatures. The record contains some evidence to the contrary. Nevertheless, the final rule is crafted such that an airport is able to use a deicer containing urea in the ev ent it is able to collect and treat the airfield discharges to meet the numeric ammonia limit. 2. Aircraft Deicing: ADF Collection Requirements a nd Effluent Limitations a. Available ADF Collection Technologies and Scope Another primary component of today’s rule concerns deicing fluid that is applied to (sprayed onto) aircraft. For the reasons explai ned in Section IV.A, EPA based the applicability of final ADF collection and di scharge requirements on ADF usag e and established a small ADF usage cut-off below which these requirements do not apply. (Permit authorities will determine the technology-based limitations for small ADF di scharges on a case-by-cas e, best professional*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 51 of 147 judgment basis.) This final rule requires the co llection of available ADF at airports that use greater than or equal to 60,000 gallons of normalized ADF per deicing season and establishes requirements for direct discharges of collected AD F. EPA estimates that 55 airports are subject to this requirement. EPA is not aware of an available and economically achievable technology that is capable of capturing 100 pe rcent of the sprayed ADF. Sec tion V.D.1 details the available technologies for collecting ADF: glycol collect ion vehicles, plug-and-pump equipment, and centralized deicing pads. EPA estimates these technologies colle ct 20 percent, 40 percent and 60 percent of available ADF, respectively. Secti on IV.A.2 explains that EPA no longer considers CDPs as representative of BAT. The Agencythen considered the other technology options described in the proposal--those with ADF coll ection requirements of 40 and 20 percent. b. Options Considered for BAT for Today’s Final Regulation EPA considered two options for today’s final rule:

 Option 1: 40 percent ADF colle ction requirement for the large ADF users (based on plug and pump with GCVs) and 20 percent ADF collection requirement for medium ADF users (based on GCVs); and

 Option 2: 40 percent ADF co llection requirement for large and medium ADF users (based on plug and pump with GCVs). Both options include the following:

 Airports with normalized ADF usage belo w 60,000 gallons/year are not subject to the ADF collection requirement in this rule (they would receive case-by-case effluent limitations in their permits for thei r aircraft deicing discharges).

 For deicing of aircraft, numeric COD limitations for direct discharges of collected ADF (based on anaerobic treatment).*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 52 of 147  For deicing of airfield pavement, BAT is iden tified as the use of only deicers that do not contain urea, implemented through either a certification that only non-urea airfield pavement deicers are used or meeting a numer ic effluent limitation for ammonia (as total nitrogen), based on product substitution. The technology basis for the numeric COD limitations in the final rule is Anaerobic Fluidized Beds (AFB), as described in Section V.D.2. The identification of AFB as best available technology for control of COD and the numeric li mitations that AFB can achieve is unchanged from proposal (74 FR 44692). The technology is t echnologically feasible and available for all airports. Under the first option, airports that use greater than or equa l to 60,000 gallons of normalized ADF annually but less than 460,000 gallons of normalized ADF (“medium ADF users,” estimated to be 42 airports) would be required to collect 20 percent of available ADF based on GCVs, and airports that use more than 460,000 gallons of nor malized ADF (“large ADF users,” estimated to be 14 airports) would be required to collect 40 percent of available ADF based on the usage of plug and pump with GCV technology. Under the second option, all airports that us e greater than or equal to 60,000 gallons of normalized ADF annually would be required to collect 40 percent of available ADF based on plug and pump and GCV technologies. In th e proposed rule, EPA considered but did not identify this as its lead option because it found its costs to be comparable to those of CDPs, while CDPs achieved greater ADF coll ection. In the proposal, EPA therefore identified centralized deicing pads as BAT. Because EPA no longe r considers centralized deicing pads a BAT candidate technology, the plug and pump with GCV option represents the technology, among*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 53 of 147 those that are widely available, that would achieve the greatest collection of ADF considered for today’s final rule. Under both options, the requirement to meet numeric effluent limits for COD for the collected ADF would need to be met prior to commingling with other wa stestreams prior to discharge. For a discussion of other technologies examined and rejected as candidates for the basis of the COD limitations, see Section VII.E. 2 in the proposed rule preamble (74 FR 44692) and Section 7 of the TDD. 3. BAT Options Selection EPA concludes that both Option 1 and Option 2 are technologically fe asible and available to all airports. Option 1 would remove 30 m illion pounds of ammonia and COD with a projected annual cost of $49million while option 2 woul d remove 33 million pounds of ammonia and COD with a projected cost of $78 million. Further, as discussed in more deta il in Section VIII, EPA finds both options are economica lly achievable. In addition, EPA examined the non-water quality impacts anticipated from compliance with today’s final rule and found that they were very minor in comparison to typical industry energy use, emissions generation and sludge generation. See Section X, “N on Water Quality Environmental Impacts.” The main difference between the two options is the pollutant reduction and projected compliance costs. Option 2 achieves greater pollutant reducti ons with greater costs compared to Option 1. Moreover, in comparing the costs to achieve reductions under either option, both options produce costs that are reasonable in terms of the pollutant reduc tions achieved ($1.64/lb and $2.37/lb for Options 1 and 2, respectively). Therefore, based on all th e factors above and that Option 2 achieves the greatest amount of pollutant reduction, EPA is identifying Option 2 as BAT and has based today’s requirements on Option 2.*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 54 of 147 C. NSPS EPA evaluated “best available demonstrated control technologies” fo r purposes of setting new source performance standards under CWA section 306. Among the collection technologies for ADF that EPA considered, CDPs collect the gr eatest level of availabl e ADF and are available to new sources in this industry. With respect to new airports, the use of CDPs does not present the space/land, safety or operational issues that would be raised in conne ction with the use of deicing pads at existing sources, nor are they so costly in comparis on to the cost of a new airport that they would be considered a “barrier to entry.” When designing a new airport, the local operating agency plans the site for all needed faci lities, such as runways, taxiways, terminal(s) and other components needed to comply with safety and environmental requirements, and this includes deicing facilities. S ee FAA Advisory Circular 150/5 070-6B, “Airport Master Plans,” and DCN XXXX. Therefore, EPA is promulga ting NSPS requirements for ADF collection at new airports based on CDPs. EPA is promulgating the same numeric C OD limitations for collected ADF that is discharged directly for new sources as it is promulgating for existing sources. The technology basis, anaerobic fluidized bed system, is appli cable to both existing and new airports. In addition, it achieves the greatest le vel of pollutant removals of those technologies considered during the development of this regulation. EPA is similarly promulgating the same require ments associated with airfield deicing for new and existing sources. EPA determined that, just as with existing sources, all new sources would be capable of eliminating the use of urea c ontaining deicers for airfiel d deicing in favor of substitute deicing products. Furthermore, product substitution represents the greatest level of reduction in ammonia among the available tech nologies considered. Accordingly, EPA*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 55 of 147 identifies product substitution of non-urea-containi ng airfield deicers as the best demonstrated available control techno logy for all new sources. As with BAT, there would be two alternatives for meeting this efflue nt limitation, either a certification requirement or a numeric limit on ammonia for all direct discharges of the stormwater from the airfields. For the purpose of this regulation, today’s final rule defines a “New Source” as a new airport. As discussed in Sec tion IV.B above, EPA has revised th e new source definition in the proposed rule and excluded new runways at exis ting airports from the definition. Meeting the new source requirements would not be an economic ba rrier to entry for new airports, as the cost of new airport construction, even at small air ports is significantly greater than the costs associated with collection and/or treatment of spent deicing fluids. See Section VIII.E. D. PSES and PSNS EPA is not promulgating PSES and PSNS fo r the Airport Deicing Category. Although some airports in the U.S. discharge ADF-contam inated stormwater to publicly owned treatment works (POTWs), EPA received no comments or other information indicating that POTWs currently have problems of pollutant pass-through, interference or sludge contamination stemming from these discharges that would neces sitate the promulgation of national categorical pretreatment standards. Like the biological treatment system that forms the basis for today’s COD limitations, POTWs typically employ biological treatment sy stems and are similarly designed to remove organic pollutants that cont ribute to COD and/or BOD 5 . In general, POTWs have the capability to achieve comparable removals to the BAT t echnology basis. However, some airports and POTWs may need to make operationa l adjustments in order to process the wastewater effectively*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 56 of 147 while avoiding POTW upset. EPA received a co mment about the Downriver Treatment Facility in Detroit, Michigan, which accepts ADF wast ewater from the Detr oit Metropolitan Wayne County Airport. The treatment plant experien ced viscous bulking due to a nutrient imbalance that occurred during the months that ADF was accepted. The issue was resolved by removing phosphorus at a later stage in the treatment plant system, rather than from the raw wastewater. The airport also made significant changes in orde r to segregate the deicing wastewater, collect and recycle the most concentrated ADF wastewater , and control the amount and concentration of wastewater discharged to the POTW. EPA is aware that high concentration or “s lug” discharges of de icing wastewater can create POTW upset. The national pretreatme nt program regulations specifically prohibit industrial users from discharging high con centrations of oxygen-demanding pollutants to POTWs if they cause interference to the POTW. See 40 CFR 403.5(b )(4). Under 40 CFR 403.5(c), control authorities may se t and enforce “local limits” for airport discharges to POTWs to implement the prohibitions listed in § 403.5(b)(4 ). This provision ensures that any potential limits would protect against POTW interferen ce by the oxygen-demanding pollutants in airport deicing discharges. See “Local Limits De velopment Guidance,” document no. EPA 833-R-04- 002A, July 2004, available on EPA’s website at http://cfpub.epa.gov/npdes/pre treatment/pstandards.cfm. . As a result, many airports that discharge to POTWs have airport-spec ific requirements on allowable BOD 5 or COD discharge loading per day. These limits on daily pollutant loadings are specific to the receiving POTW. Airports usually meet this requirement by stor ing deicing stormwater in ponds or tanks and metering the discharge to meet the POTW permit loading requirements.*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 57 of 147 VII. Technology Costs and Pollutant Reductions A. Compliance Costs 1. Overview EPA estimated industry-wide compliance costs for today’s rule. This section summarizes EPA’s approach for estimating compliance costs, while the TDD provides detailed information on these estimates. All final co st estimates are expressed in te rms of 2006 dollars and represent the cost of purchasing and in stalling equipment and control technologies, annual operating and maintenance costs, and associated monitoring and reporting requirements. In general this approach is the same as the one used in the pr oposal. However, some modifications were made for costing specific technology pieces in the cos ting models, including the numbers of GCVs per airport and the manner in which airports woul d store collected ADF containing wastewater. EPA estimated compliance costs associated with today’s rule using data collected through survey responses, site visits, sampling epis odes, specific airport requests and information supplied by vendors. Under this ru le, certain airports would be re quired to collect a percentage of their available ADF and treat the collected wast ewater to comply with numeric limitations if discharged directly. EPA estimated costs for anairport to install technology to comply with today’s requirements, as well as annually to operate and maintain equipment and perform required monitoring or other activities to de monstrate ongoing compliance. EPA’s cost estimates represent the incrementa l costs for a facility when its existing practices would not lead to compliance with today’s rule. EPA calculated costs based on a computerized design and cost model developed for each of the technology options considered. EPA developed facility-specific costs for each of the airport industry questionnaire re spondents (149 facilities), where each facility was treated as a*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 58 of 147 “model” airport. Because the questionnaire resp ondents represent a subset of the industry, EPA subsequently modeled the national population by adjusting the costs upward to estimate the entire affected airport population. The questionnaire responses provided EPA withinformation on three consecutive deicing seasons (2002 to 2005) for each of the model facil ities. Some portions of EPA’s costing effort reflect the airports' operations as reported for the three seasons. For example, estimates of applied deicing chemicals were taken as an average of the years for which the information was reported. In instances where asp ects of an airport's operation ch anged over the three-year period, EPA used the most recent information. EPA first established existing conditions (i.e ., baseline) for each model airport based on information and site plans submitted as part of the airport questionnaire. EPA then determined what upgrades or changes, if any, would be requ ired to comply with today’s final rule. For example, in general, when an airport lacked a comparable collection system to the one used as the basis for today’s rule, EPA included costs fo r installation/operation an d maintenance of plugand-pump systems in conjunction with GCVs. 2. Approach for Estimating Airf ield Pavement Deicing Costs Today’s rule sets requirements for an airport to certify it uses non-ur ea-containing airfield deicers. Through the airport questionnaire respon ses, EPA estimates that 198 airports will be subject to today’s requirements. Of these 198 airports, 37 airports use urea containing deicers for airfield pavement deicing. As detailed in Section V.D.4., EPA based its airfield pavement deicing requirement on product substitution. EPA cal culated the cost for facilities to substitute the urea containing deicers with another widely available pavement deicer that does not produce ammonia in the wastewater. EPA chose to model the substitution costs on what it would cost to*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 59 of 147 switch to potassium acetate, specifically becau se that product accounts for 63 percent of the applied chemical airfield deicerusage (by weight) in the U.S. These incremental costs include capital costs associated with a pplication equipment and storage, as appropriate, as well as the differential chemical costs. EPA assumed that those airports that currently do not use urea containing deicers as a means of pavement deicing would experience no cost associated with this portion of today’ s regulation. Using the facility area usage as provided in the airport quest ionnaire and available literature on typical urea-contai ning pavement deicer application rates, EPA estimated the airfield area that was annually deiced at each model facility. Us ing the estimated model facility deicing area in conjunction w ith the estimated $2.92/1,000 ft 2 cost of potassium acetate, EPA was able to calculate the cost per model facil ity to perform airfield deicing with potassium acetate. This cost was compared to the questi onnaire reported urea cont aining deicer costs to determine the incremental costs of switching ch emical airfield deicer s. See the TDD for additional details on costing for airfield deicing product substitution. 3. Approach for Developing Aircraft Deicing Costs Under this rule, certain air ports are required to collect a percentage of their available ADF, and treat the collected wastewater to co mply with numeric effluent limitations if it discharges directly. EPA estimated the costs for an airport to comply with collection and treatment requirements, as applicable, as well as performing required monitoring to demonstrate compliance. Of the 198 airports subject to BAT, EPA expects that 55 airports will exceed the threshold for ADF use that would trigger the co llection/discharge requirement. Costing for ADF collection is not relative to base line practices in all instances, as an airport's existing collection technology may not be incrementally upgradeable to achieve the required co llection efficiency.*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 60 of 147 As such, EPA assessed all costs to comply with today’s regulation with the assumption that any airport required to make upgrades to their collec tion and/or treatment system to meet today’s requirement, would be starting from a baseline of zero collection and treatment. Note that this assumption does not carry through to pollutant rem ovals, as baseline removals are accounted for when assessing pollutant removals associated wi th today’s regulations (see section VII.B for more detail on the pollutant removal calculations). EPA first established existing conditions for each model airport based on information and site plans submitted as part of the airport questio nnaire. EPA then determined what upgrades, if any, would be required to comply with today’s re quirements. As explained above, in general, when an airport lacked a compar able collection system to the one used as the basis for today’s rule, EPA included costs for installation/im plementation of plug-and-pump systems in conjunction with GCVs and AFB treatment system. For those airports that are required to collect additional ADF and meet associated discharge requirements to comply with today’s rule, EPA estimated costs for storage/equalization (and associated piping to transfer collected ADF to storage) as part of the costs of the treatment technology. The final rule does not require nor is it based on collecting the full volume of wastewater generated in a deicing season. Rather, storage is included as part of the technology basis for flow and/or pollutant eq ualization to support the AFB treatment system. Where EPA estimates an airport will incur capi tal costs associated with ADF collection and discharge requirements, the Agency included co sts for above-ground storage tanks, since aboveground storage tanks will have less of an impact on subsurface utilities, for which EPA does not have site-specific information.*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 61 of 147 For the 15 airports that EPA anticipates will need to collect additional quantities of ADFcontaminated stormwater to comply with toda y’s rule, EPA assumed these additional quantities would be discharged directly, thus requiring treatment to comply with the COD limitations. This includes all airports that EPA estimates collect less than 40 percent of available ADF. Specifically, this includes those facilities th at currently collect some portion of ADFcontaminated stormwater and subsequently disc harge indirectly to a POTW or a centralized waste treatment (CWT) facility. EPA recognizes th at an airport may decide to discharge to a POTW or CWT facility rather than directly discha rge its wastewater. While this is likely a lower cost alternative in some cases, EPA did not assume that airports could di scharge to a POTW or CWT, because the Agency does not have enough information about the capacity or willingness of a specific POTWs to receive these volumes of wastewater. To the extent that an airport selects this alternative, EPA ma y have over-costed the option. Additionally, airports may have costs associ ated with permit application requirements or demonstrating compliance with today’s rule, in cluding assessing yearly ADF usage, determining ADF stormwater collection, syst em inspections and COD monito ring. Monitoring requirements will continue to be determined by the permitting authority. However, for purposes of estimating monitoring costs associated with today’s rule, EPA assumed that ai rports that directly discharge collected ADF would take a 24-hour composite sa mple and analyze that for COD, and perform that analysis seven times per w eek for the duration the treated discharge occurs. EPA made a similar assumption for purposes of computing th e weekly average effluent limitation (see the TDD for additional details). As a conservative estimate, EPA assumed a six-month discharge duration season for all modeled facilities. 4. Calculation of National Costs*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 62 of 147 EPA categorized all of the costs as either capital costs (one-time costs associated with planning or installation of technol ogies), or as operations and maintenance (O&M) costs (costs that occur on a regular ongoing basis such as monitoring or annual purchases of deicing materials). EPA amortized these capital costs over the lifespan of the capital improvement. For additional information on amortization, see the EA. Finally, EPA combined the amortized capital costs with the annual O&M costs to calcul ate the total annual costof the regulation for that model facility. EPA then utilized statistical weights assi gned to each of the 149 model facilities to calculate a national estimated cost of $78 million fo r complying with the rule. Further discussion of all of the calculations discussed can be found in the TDD and in the EA. B. Approach to Estimating Pollutant Reductions 1. Overview The pollutants of concern associated with airfield and aircraft deicing and anti-icing chemicals are discussed in Section 6 of the TDD. These chemicals commingle with stormwater and may be discharged to the environment. These discharges are of environmental concern because the biodegradation of deicing chemicals results in oxygen depletion in the receiving water body. Moreover, some of these pollutants, such as ammonia, have toxic properties. Pollutant loadings from airport deicing ope rations are challenging to estimate because they are highly variable and airport-specific. Be cause the use of deicing and anti-icing chemicals is weather dependent, the pollutant loadings at each airport vary based on weather conditions. The pollutant loadings also vary from airport to airport based on each ai rport’s climate. In addition, the amount of applied chemical that is discharged to surface water is airport specific,*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 63 of 147 based on the existing stormwater separation, collec tion, and/or containment equipment present at each airport. Due to the variable nature of these pollutantloads, EPA developed a baseline (or current) pollutant loading methodology based on the usage of ADF and airfield chemicals at the airports responding to the survey questionnaires. Th e methodology takes into account EPA’s existing data sources and provides a better estimate of the loadings than those based on sporadic monitoring data alone. Similar to the cost ing methodology, EPA devel oped facility-specific baseline loads for a subset of the industry (i.e., model facilities). For those model airports where existing practices would not leadto compliance with today’s rule, EPA then calculated the incremental pollutant removals associated with compliance. EPA subsequently adjusted the incremental pollutant removals upw ard to estimate the entire aff ected airport population. This approach is the same as the approach taken in the proposal. 2. Sources and Use of Available Data While developing the polluta nt loading models, EPA cons idered the following data

sources:

 Pavement deicing chemical usage/purc hase information for the 2002/2003, 2003/2004, and 2004/2005 deicing seasons, as reported by airport authoriti es in the Airport Deicing Questionnaire;

 ADF purchase information for the 2002/2003, 2003/2004, and 2004/2005 deicing seasons, as reported by air carriers inthe Airline Deicing Questionnaire;

 Standard airport information available from the FAA and the Bureau of Transportation Statistics (BTS), including the number of operations and departures by airport;*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 64 of 147  Weather information for each airport fr om National Oceanic and Atmospheric Administration (NOAA), including temperatur e, freezing precipit ation, and snowfall data;

 Existing airport stormwater collection and c ontainment systems, as reported by airport authorities in the Airport Deicing Questionnaire;

 Standard chemical information about ADF and pavement deicing chemicals, including molecular formulas and densities; and

 Analytical data from EPA sampling ep isodes of airport de icing operations. a. Baseline Loading Calculations The Agency estimated the total amount of pavement deicing chemicals and ADF used based on data collected in the Airport and Air line Questionnaires. The Airport Questionnaire respondents reported the purchase/usage amount, c oncentration, and brand name of pavement deicing materials. EPA collected ADF purchas e data from airlines with 1,000 or more departures operating at selected airports through the airline questionnaire . (During questionnaire development, airports indicated they did nothave information on ADF usage and that EPA should direct this question to airlines. Purchase data were collected because the airlines stated that purchase data were most r eadily available, while usage data was not.) For the purposes of these loading calculations, EPA estimated that the annual amount purchased was equal to the amount used for a deicing season. For instances where EPA did not have ADF purchase data for every airline operating at a particular model airp ort, EPA extrapolated the amount of ADF used by the reporting airlines to estimate the total amount of ADF used by the entire airport. This was done based on the number of airport operations (dep artures) at the reporti ng airlines versus the total number of airport operations. In addition to the 56 airports for which EPA collected ADF*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 65 of 147 purchase/usage data from the airline tenants, 10 airports reported the to tal volume of their ADF usage to EPA in their comment section of the Airport Deicing Questionnaire, resulting in estimates of total ADF usage for 66 model airports. Using the airline and airport ADF purch ase and usage data obtained from the questionnaire; airport departure data; and clim ate data, EPA developed a relationship between the amount of ADF used, and the climate and size of each model airport. EPA then used this equation to estimate the total gall ons of ADF used at model airports that did not have ADF usage data in the Airport or Airline Questionnaires. (EPA is aware th at a core component of today’s regulation is airport-sp ecific ADF usage estimates. However in order to prevent mandatory survey responses marked as CBI from bei ng released, EPA is not revealing the exact methodology for modeling this ADF usage due to the potential for the deduction of CBI data through back calculation). Once the amount of ADF used at each mode l airport had been determined, EPA needed to determine the amount of ADF available for dir ect discharge. EPA assumes that 75 percent of applied Type I ADF falls onto the pavement at the deicing area and is available for discharge. EPA assumes that 10 percent of Type IV ADF falls to the pavement in the deicing area and is available for discharge; the rema ining 90 percent adheres to the plane. (See the TDD for more information on these estimates.) EPA then multiplied the total amount of applied ADF for each model airport by the appropriate percent available for discharge to determine the amount of ADF available for discharge. Note th at collection requirements in the rule are specified as percentages of ADF available for discharge, not percentages of total ADF applied. Evaluating the amount of ADF available for discharge, coupled with the es timated baseline collection rate, results in the*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 66 of 147 total amount of discharged avai lable ADF. EPA then calculated the amount of COD loading associated with these discharges as described below. Airfield pavement deicing chemicals are ap plied at various airside locations such as runways, taxiways and ramps. Theoretically, th e amount of pavement deicers being discharged could range from approximately zero percent, for chemicals that infiltrate highly permeable soils in unpaved areas during a thaw, to virtually 100 pe rcent for paved areas near storm drains. In general, soil in unpaved areas is frozen during deicing season and is impermeable, promoting the overland flow of stormwater and pollutants to surface waters. Estimating the amount or proportion of pavement deicers disc harged at a particular airport is difficult without performing a detailed study at the airport. EPA has not received any such detail ed studies, nor other information from airports indicating that pave ment deicers are absorbed into soil during the deicing season. Therefore, the Agency assume d for this rulemaking th at 100 percent of the pavement deicers used could be discharged to surface waters. This means the estimates of baseline pollutant loadings and removals a ssociated with pavement de-icing are upper bound estimates. EPA then calculated the amount of C OD loading associated with airfield chemical use and discharge as described below. To calculate the COD loading associated with either ADF or airfield chemical discharge, EPA determined the theoretical oxygen demand (Th OD) associated with the degradation of each of the deicing chemicals. EPA based the ThOD estimate on the molecular formula of the chemical and the stoichiometric equation of th e breakdown of the chemi cal to the end products of carbon dioxide and water. EPA assumed that the chemical would comp letely degrade in the environment over time and therefore the calculat ed ThOD load would be equivalent to the COD load. EPA estimated the COD load associated with each reported chemical based on the*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 67 of 147 calculated mass of the chemical discharged, the molecular weight of the chemical, the ThOD, and the molecular weight of oxygen. EPA estimated the ammonia load asso ciated with deicers containing urea on the chemical equation for the breakdown of urea to ammonia, the mass of urea use, and the molecular weights of urea and ammonia. See Section 9 of the TDD for more information and example calculations of baseline loadings associated with ADF and airfield deicers. b. Calculation of Pollutant Removals After determination of baseline loadings , EPA calculated total reductions of COD and ammonia associated with a national implementation of today’s rule. i. Aircraft Deicing Rela ted Pollutant Removals EPA estimated the amounts of COD that woul d be reduced by the rule, by estimating the existing baseline loadings associated with aircraft deicing at model airpor ts and comparing that to the COD load that would be discharged af ter complying with the rule (i.e., COD load discharged if 40 percent of av ailable ADF were collected and treated to meet the required discharge limitation). If a particular airport w ould be subject to a coll ection requirement of 40 percent under this rule and it currently is es timated to collect a greater proportion of available ADF, then no load removals were estimated for that airport. ii. Airfield Deicing Related Pollutant Removals EPA calculated ammonia and COD baseline load s for those model facilities using deicers containing urea. The Agency then calculated ammonia and COD loads for those same model facilities if they replaced thei r deicers containing urea with th e substitute product, potassium acetate (which does not form ammo nia and exerts a lower COD than urea). EPA computed the*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 68 of 147 total load reduction by s ubtracting the ammonia and COD loadi ngs between the baseline and the regulatory compliance conditions. iii. National Extrapolation These calculated loading reductions, summed for both airfield and aircraft deicing chemicals, as applicable, were then extrapolated by multiplyin g the pollutant removals for each model facility by the airport survey weighting factors to dete rmine national loads for the entire industry for each regulatory option considered for today’s rule. C. Approach to Determining Long-Term Averages , Variability Factors and Effluent Limitation Guidelines and Standards This section describes the statistical methodology used to develop the daily maximum and the maximum for weekly average effluent li mitations and new source performance standards representing the BAT and BADCT levels of control for COD. EPA also used the same statistical methodology to develop the daily maximum lim itation/standard for ammonia that is a compliance alternative when dei cers containing urea are applied to runways. For simplicity, the following discussion uses the term “limitation” to refer to effluent limitations guidelines, standards, and the compliance alternative. EP A has promulgated the same limitations for each level of collection requirement, because the tr eatment technology and performance are the same regardless of the amount of fluid collected. The following sections describe the data sele ction criteria; the statistical percentile basis of the effluent limitations; rationales for certain limitations; the calculations; the recommended long-term average value for treatment operations ; and the engineering ev aluation of the model technology’s ability to achieve the levels required by the limitations. 1. Criteria Used to Select Data as the Basis of the Limitations*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 69 of 147 Typically, in developing effluent limitati ons for any industry, EPA qualitatively reviews all the data before selecting the appropriate da ta to use for calculating the limitations. EPA typically uses four criteria to assess the data. One criterion gene rally requires that the influent and effluent represent only wastewater from th e regulated operations (e.g., deicing), and do not include wastewater from other sources (e.g., sanitary wastes). A second criterion typically ensures that the pollutants were present in the in fluent at sufficient con centrations to evaluate treatment effectiveness. A third criterion generally requires that the facility must have the technology and demonstrate proper operation of the technology. A fourth criterion typically requires that the data cannot re present periods of treatment ups ets or shutdown and start-up periods. (Shutdown periods can result from upsetconditions, maintenance, and other atypical operations.) EPA has adapted the applicati on of the fourth general criter ion for data corresponding to start-up periods to reflect some unique characterist ics of treating discharges from aircraft deicing operations. Most industries in cur start-up conditions only dur ing the adjustment period associated with installing new treatment syst ems. During this acclimation and optimization process, the concentration values tend to be high ly variable with occasional extreme values (high and low). After this initial adjustment period, th e systems should operate atsteady state for years with relatively low variability around a long-termaverage. Because st art-up conditions reflect one-time operating conditions, EPA generally excludes such data in developing the limitations. In contrast, EPA expects airpor ts to encounter start-up opera tions at the beginning of every deicing season because they probably will cease treatment operations during warmer months. Because this adjustment period will occur every year for the Airport Deicing Category, EPA has included start-up data in the data set used as the basis of the limitations. However, through its*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 70 of 147 application of the other three criteria, EPA excluded extreme c onditions that do not demonstrate the level of control possible with proper operatio n and control even durin g start-up periods. For detailed information on these exclus ions, see Section 14 of the TDD. In part, by retaining start-up data for the li mitation’s development, the limitations will be achievable because EPA based these limits on typi cal treatment during the entire season. Once the treatment system reaches steady state, EP A expects a typically we ll-designed and operated system for the collected deicing fluid to run co ntinuously until the end of the deicing season. 2. Data Used As Basis of the Effluent Limitations As explained in Section 8 of the TDD, the technology basis for the COD numerical limitations associated with discharges of colle cted ADF wastewater is anaerobic fluidized bed (AFB) biological treatment. Of the effluent data available to EPA, 2,562 concentration values for COD met the requirements in the criteria desc ribed above and are the basis of the COD final effluent limitations. The concentration values are measurements of filtered effluent collected from Albany Airport’s two-unit anaerobic tr eatment system. The 2,562 COD values were collected by the airport during it s daily monitoring of COD ov er ten deicing seasons (i.e., December 1, 1999 through April 10, 2009). The basis for today’s effluent limitation regarding airfield deicing chemicals is product substitution. EPA also established ammonia disc harge limitations as a compliance alternative. Ammonia naturally occurs in airport discharges as a result of excretions from wildlife that enter the stormwater; therefore, EPA determined it would not be appropriate to se t this limitation at the non-detect level. Moreover, depending on a spec ific airports' drainage system, a portion of airfield deicing stormwater may be routed to the treatment system utilized in treating the collected ADF. Further, the anaerobic biologica l treatment system (AFB) that is identified as*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 71 of 147 BAT/BADCT for treating collected ADF will itself produce amm onia discharges as a byproduct of treatment. Therefore, where ai rfield deicing stormwater that is free of urea contamination is routed through the AFB treatment system, the discharge after treatm ent may have ammonia concentrations higher than the non-detect le vel (see DCN xxx). Consequently, EPA used ammonia effluent discharge data from the same AFB system it used to establish BAT/BADCT discharge requirements for ADF, located at Al bany, to establish today’s ammonia compliance alternative. Five ammonia c oncentration values available from Albany met the limitations criteria described above. The five ammonia values were coll ected by EPA during its sampling episode (February 5 through February 9, 2006). 3. Statistical Percentile Basis for Limitations EPA uses a statistical framework to estab lish limitations that well-operated facilities are capable of complying with at all times. By we ll operated facilities, EPA means facilities that represent the BAT/B ADCT level of control. Statistical me thods are appropriate for dealing with effluent data because the quality of effluent, even in well-operated systems, is subject to a certain amount of variability or uncertaint y. Statistics is the science of dealing with uncertainty in a logical and consistent manner. Statistical me thods together with engineering analysis of operating conditions, therefore, prov ide a logical and consistent fr amework for analyzing a set of effluent data and determining values from the data that form a reasonable basis for effluent limitations. Using statistical methods, EPA has de rived numerical values for its daily maximum limitations and weekly average limitations. The statistical percentiles upon which the lim itations are based are intended to be high enough to accommodate reasonably anticipated variab ility within control of the facility. The limitations also reflect a level of performance consistent with the CWA requirement that these*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 72 of 147 limitations be based on the best available tec hnologies (or BADCT for ne w sources), including proper operation and maintenan ce of these technologies. In establishing daily maximum limitations, EPA’ s objective is to rest rict the discharges on a daily basis at a level that is achievable for an airport that targets its treatment system design and operation at the long-term average while allowing for the variability around the long-term average that results from a well-operated system. This variability means that at certain times airports may discharge at a level th at is greater than the long-term average. This variability also means that airports may at other times discharg e at a level that is lower than the long-term average. To allow for possibly higher daily di scharges, EPA has established the daily maximum limitation at a relatively high level (i.e., the 99 th percentile). EPA has consistently used the 99 th percentile as the basis of the daily maximum lim itation in establishing limitations for numerous industries for many years and numerous courts have upheld EPA’s approach. EPA typically establishes limitations based upon st atistical percentile estimates and has done so for the weekly average limitation in today’s final rule. In its derivation of the weekly average limitation for COD, EPA used an estimate of the 97th percen tile of the weekly averages of the daily measurements. This percentile basis is the midpoint of the percentil es used for the daily maximum limitation (i.e., 99th percentile of the di stribution of daily values) and the monthly average limitation (i.e., 95th percentile of the di stribution of monthly average values). Courts have upheld EPA’s use of these per centiles, and the selection of the 97 th percentile of a weekly average of the daily measurements is a logical ex tension of this practice. Compliance with the daily maximum limitation is determined by a single daily value; therefore, EPA considers the
99 th percentile to provide a reasonable basis for the daily maximum limitation by providing an allowance for an occasional extreme discharge. Because compliance with the monthly average*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 73 of 147 limitation is based upon more than one daily measur ement and averages are less variable than daily discharges, EPA has determin ed that facilities should be cap able of control ling the average of daily discharges to avoid extr eme monthly averages above the 95 th percentile. In a similar manner to the monthly average limitation, compliance with the weekly average limitation also would be based upon more than one daily measurem ent. However, the airport would monitor for a shorter time and thus would have fewer opportu nities to counterbalance highly concentrated daily discharges with lower ones. Cons equently, EPA has determined that the 97 th percentile is an appropriate basis for limiting average discharges on a weekly basis. EPA considers the use of the 97 th percentile for the weekly average limitation a level that is achievable for airports using the model technology. EPA also considers this le vel of control in avoiding extreme weekly average discharges to be possible fo r airports using th e model technology. 4. Rationale for Establishing Limitation on WeeklyAverages Instead of Monthly Averages for COD in Effluent Discharges From a monitoring perspective, EPA considers the weekly average limitation to be a better fit than the monthly averag e limitation for the deicing discha rges. In this situation, the weekly average limitation would apply to every week that the treatment system operates during the deicing season. A weekly average limitation preserves EPA’s intention for an additional restriction beyond the daily maximum limitation thatsupports its objectiv e of having airports control their average discharges at the long-term average level. When it establishes monthly average limita tions, EPA’s objective is to provide an additional restriction to help ensure that facilities target their treatment systems to achieve the long-term average. The monthly average lim itation requires facili ties to provide on-going control that complements controls imposed by the daily maximum limitation. To meet the*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 74 of 147 monthly average limitation, a f acility must counterbalance a value near the daily maximum limitation with one or more values well below the daily maximum limitation. To achieve compliance, these values must result in a monthl y average value at or below the monthly average limitation. The deicing season is unlikely to start atthe beginning of a calendar month and close exactly at the end of a calendar month. This means that the facility would be monitoring at a reduced frequency during those two months. Increasing or d ecreasing monitoring frequency does not affect the statistical prope rties of the underlying distributi on of the data used to derive the limitations. However, monitoring less frequen tly theoretically results in average values that are more variable. For example, monthly av erage values based on 10 monitoring samples per month would be (statisti cally) expected to include some averag es that are numerically larger (as well as some that are numerically smalle r) than monthly average values based upon 20 monitoring samples. Because of this reduced monitoring, an airport might have trouble in complying with the monthly average limitation even with an otherw ise well-operated and controlled system. In other words, because it wa s not monitoring as frequently, the airport would have fewer opportunities to counterbalance hi gh concentrations with lower values. 5. Rationale for Promulgating a Limitation Only fo r Daily Discharges of Ammonia in Effluent Discharges EPA believes that it is appropriate to relyon a daily maximum limitation to ensure that airports appropriately control ammonia levels as airports might have difficulties in complying with any average limitation due to monitoring less frequently than assumed in the statistical calculations (see discussion rela ted to monitoring for COD). Unlike for the COD limitation, EPA is not promulgating a weekly ammonia effl uent limitation. The technology basis for the*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 75 of 147 COD effluent limitations would operate thr oughout the deicing seas on with continuous discharges allowing for weekly monitoring. In contrast, urea containing deicers are applied to airfield pavement as needed, and discharges would occur for a short time after the initial application, as the urea works its way through the stormwater collection and any associated treatment system that may be present. Most airports would have non-continuous and somewhat infrequent urea discharges. Cons equently, it would be difficult to assume a single value for the monitoring frequency that could reasonably be applied to all ai rports, regardless of climatic conditions. Additionally, EPA expects airports to select product subst itution (i.e., non-urea deicers) rather than the compliance altern ative that requires collection and treatment of runway deicing contaminated stormwater. Thus, it is possible that no airports will be subject to any limitation on ammonia discharges. 6. Calculation of Limitations for COD and Ammonia For COD, EPA used nonparametric statistical me thods to estimate the percentiles used as the basis of the daily maximum and weekly average limitations. A simple nonparametric estimate of a particul ar percentile (e.g., 99 th ) of an effluent concentra tion data set is the observed value that exceeds that percent (e.g., 99) of the observed data points. For the daily maximum limitation for COD, EPA used the nonparametric method to derive a 99 thpercentile of the more than 1,200 daily measurements for each unit, and then set the limitation equal to the median of the two 99 th percentile estimates, or 271 mg/L. The median is, by definition, the midpoint of all available data va lues ordered (i.e., ranked) from smallest to largest. In this particular case, because there ar e two units, the median is equal to the arithmetic average (or mean).*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 76 of 147 For the weekly average limitation of COD, EPA first calculated, for each unit, the arithmetic average of the measurements observed during each week, excluding weekends. EPA then used the nonparametric method to derive a 97 th percentile of the more than 200 weekly averages for each unit, and set the limita tion equal to the median of the two 97 th percentile estimates, or 154 mg/L. For ammonia, EPA used a parametric approach in estimating the 99 th percentile based upon the data collected during EPA's 5-day samp ling episode. The cal culations assume the ammonia concentrations can be modeled by a lognormal distribution. EPA's selection of parametric methods, such as a model based on the lognormal distribution, used in developing limitations for other industries is well documente d (e.g., Iron and Steel ( 40 CFR part 420), Pulp, Paper and Paperboard (40 CFR part 430), Meta l Products and Machinery (40 CFR part 438) categories). Variance estimates based upon parametric methods can be adjusted for possible biases in the data. The limitation of 14.7 mg/L includes such an adjustment for possible bias from positive autocorrelation. When data ar e positively autocorrelated, it means that measurements taken close together in time (such as 1 or 2 days apart) are more similar than measurements taken farther apart in time, such as a week or month apart. The adjusted variance then better reflects the underlyi ng variability that would be pres ent if the data were collected over a longer period. 7. Derivation of Long-Term Average for COD and Ammonia: Target Level for Treatment Due to routine variability in treated effluent, an airport that discharg es consistently at a level near the values of the daily maximum limitation or the weekly average limitation, instead of the long-term average, may experience freque nt values exceeding the limitations. For this reason and as noted previously inthis section, EPA recommends th at airports design and operate*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 77 of 147 the treatment system to achieve the long-term av erage for the model technology. Thus, a system that is designed to represent the BAT/BADCT level of control will be capable of complying with the promulgated effluent limitations. For COD, EPA recommends that airports ta rget treatment systems to achieve the longterm average value of 52.8 mg /L, which is the median of the two averages, of 52.28 and 53.40 mg/L, of the daily values from the two units. Th e daily allowance for vari ability, or the ratio of the limitation to the long-term av erage, is 5.13. (EPA usually refe rs to this allowance as the “variability factor.”) In othe r words, the daily maximum limita tion of 271 mg/L is about five times greater than the long-term average ach ievable by the model technology. The weekly variability factor is 2.92. For ammonia, EPA derived its recommended long-term average value of 5.24 mg/L from the (statistical) expect ed value of the lognormal distributi on. The daily maximum limitation of 14.7 mg/L is about three times greater than th e long-term average, of 5.24 mg/L, achievable by the ADF treatment model technology. Ammonia is generated as a by- product of the model technology, and EPA expects the con centrations of ammonia to have similar variability to what is being treated (i.e., COD). Incontrast to the COD limitations, which are based on a mixture of start-up and steady state periods, the ammonia limitation is based upon data collected only during steady state operations. 8. Engineering Review of Effluent Limitations In conjunction with the stat istical methods, EPA performs an engineering review to verify that the limitations are reasonable base d upon the design and expected operation of the control technologies and the facil ity conditions. During the site visit and sampling trip at the Albany treatment plant, EPA confirmed that the airport used the model technologies, specifically*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 78 of 147 AFB. EPA subsequently contac ted the plant personnel to obtain more information about the installation and opera tion of the model technologies. EPA us ed this engineering information to select the subset of data from which to develop the effluent limitations. As part of this engineering review, EPA concluded that the values of the limitations were consistent with the levels th at are achievable by the model t echnologies. Next, EPA compared the value of the effluent limitations to the data values used to calculate the limitations. None of the data selected for ammonia were greater th an its daily maximum limitation which supports the engineering and statistical conclu sions that the limitation value is appropriate. Because of the statistical methodology used for the COD limitations (i.e., use of percentiles), some values were appropriately greater than the limitations. See section VII.C.3. Even though we would expect this statistically, EPA looked at the values th at exceed the limitations from an engineering perspective. EPA wanted to ensure there were no underlying conditions contributing to such exceedances. In particular, EPA looked at deicing season, influent concentrations, and start-up operations. In evaluating the impact of the deicing seasons, EPA concluded that the higher values did not seem to be predominant in any one season. In particular, the higher values occurred one to seven times in each of eight seas ons. In evaluating influent concentrations, EPA found that influent concentrations were generally well-controlled into the treatment plant. In general, the treatment system adequately treate d even the extreme influent values, and the high effluent values did not appear to be the result of high influent di scharges. In considering start-up operations, EPA noted that the higher values occurred in every month from December through May, except in April, and thus, the limitations ap pear to provide adequate allowance for start-up operations.*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 79 of 147 VIII. Economic Analysis A. Introduction EPA’s economic analysis assesses the costs and impacts of the final effluent guidelines on the regulated industry. This section expl ains EPA’s methodology and the results of its economic analysis. With one exception, all costs, ai rport counts and other re sults in this section are presented using sample weights to expand results from the surveyed airports to represent the entire population of airports poten tially affected by the rule. Th e single exception, the results of the debt service coverage analys is, is clearly marked as “unwei ghted.” In addition, all cost figures are presented in 2006 dollars. B. Annualized Compliance Cost Estimates EPA considered two regulatory options for today’s final rule. Under both, all airports subject to BAT or NSPS would have requirements with respect to airfield deicing stormwater (certify no use of airfield deici ng products that contain urea, or airfield pavement discharges must achieve a numeric limit for ammonia). EPA estimates that 198 airports—those that perform deicing operations with at least 1,000 annual non-propeller aircraft departures--are subject to the airfield deicing requirements. 1 In addition, a subset of those airports—airports with annual normalized ADF usage equal to or exceeding 60,000 gallons per year (55 airports)— would also need to meet requirements related to wastewater from aircraftdeicing (ADF collection and COD discharge limita tions). The regulatory options that EPA considered differ in the level of ADF collection required for airc raft deicing. Option 1 would set a two-tier requirement: 20 percent collection and treatment for airports w ith at least 60,000, but less than

1 Because many airports do not meet the applicab ility criteria, EPA estimates that approximately 184 primary airports, 135 non-primary airports, and almost 3,000 general aviation airports are not regulated under the final rule.*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 80 of 147 460,000 gallons of annual normalized ADF usage, and 40 percent collection and treatment for airports with at least 460,000 ga llons of annual ADF usage. Op tion 2 would require 40 percent collection and treatment for all airports with at least 60,000 ga llons of annual normalized ADF
usage. EPA selected Option 2 for promulgation in th is final rule. EPA estimates the technologies identified in this notice to comply with the BAT limitations will cost affected airports $314.4 million in total capital costs over 20 years in nominal terms EPA projects the effective service life of glycol collection vehicles (GCV) and blockand-pump technologies to be 10 years; all other components necessary to meet today’s requirements have an effective service life of 20 years. Theref ore, EPA selected a 20 year analytic period and incorporated replacement capital expenditures in year 10, in addition to the initial capital expenditure. As such, we estimat ed total capital costs to include all initial and replacement capital expenditures for GCV and plug-and-pump. However, because the replacement capital expenditures occur 10 years after promulgation, the di scounted present value (PV) of those expenditures is le ss than their current value. EPA uses 3 and 7 percent interest rates for two purposes. First, it is used to discount future capital replacement costs required when th e 20-year analytic period exceeds the effective service life of a technology. Second, it represents the opportunity cost of capital to industry, and thus, essentially the interest rate the i ndustry may be charged if it borrows money. EPA discounted and annualized the stream of capital costs projected to be incurred by industry over 20 years using two di fferent discount rates. EPA has determined that a 3 percent real discount rate best represents society’s preferences for future consumption of goods and products, including improved environmental cond itions (EPA. 2010. “Guidelines for Preparing*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 81 of 147 Economic Analyses.” Document no. EPA-240-R-10- 01). Thus, discounting and annualizing the future stream of costs using a 3 percent real discount rate best represents th e cost of the rule to the nation as a whole. However, in order to be ab le to continue to attrac t capital in the long run, businesses would be expected to meet the opportunity cost of capit al; therefore capital costs are also using a 7 percent re al rate (as determined by OMB) to represent the long-term opportunity cost of capital to industry. The PV of capital costs under the final rule is $309.0 million based on the societal discount rate of 3 percent, and $299.0 million over the 20-year analytic period using the 7 percent private opport unity cost of capital rate. The annual cost of operating and maintaini ng the technologies id entified as BAT for deicing for this final rule, is estimated at $52 million. Adding this operation and maintenance cost to the annualized capital costs, the rule has aggreg ate national costs of $72.1 million per year using a 3 percent discount rate and annua lized costs to industry of $78.4 million using a 7 percent rate (in 2006 dollars). Table VIII-1 presents projected costs for the final rule, as well as the other option examined.

Table VIII–1. Costs to Existing Airports th at Deice Aircraft and Airfield Pavement [2006 $ millions – 198 airports (weighted)]

Option Total Capital

Costs Present Value of Capital

Costs Annualized Capital

Costs Annual O&M Costs Total Annualized Compliance Costs
3 Percent Real Discount Rate 1 $250.3 $243.7 $15.9 $28.4 $44.3 2 [a] $319.9 $309.0 $20.2 $52.0 $72.1
7 Percent Real Discount Rate 1 $250.3 $237.6 $21.0 $28.4 $49.4 2 [a] $319.9 $299.0 $26.4 $52.0 $78.4 [a] Selected option.*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 82 of 147 C. Economic Impact Methodologies For the purposes of the economic impact analys is, the distinguishing feature of airports that makes the analysis different from more traditional analyses EPA would perform for a forprofit manufacturing industry is th at all potentially affected ai rports are publicly owned and operated by local, county, or state governments, or by quasi-governme ntal authorities created to operate the airport. As governmental or quasi-gov ernmental entities, airpor ts do not earn a profit or loss in the traditional financial sense; in fact, many airports have been operated with the expectation that they will break even financially, with the airlin es that use the airport legally required to cover expenditure s in excess of costs. Airlines may also be impact ed by today’s rulemaking. In the vast majority of cases airlines are not directlysubject to today’s requ irements. In such cases, impacts to airlines are considered secondary impacts. Historically, EPA determines economic achievability based on primary or direct impacts only (i.e., impacts to NPDES permit holders directly subject to ELG requirements) and does not eval uate secondary impacts. At the time of the proposal, EPA elected to evaluate secondary impacts to airlin es because of the unique contractual relationship between airports and airlines, because airlines ar e the entities that use ADF, and because airlines are occasionally co-permittees (but never the principal permittee) at an airport. In a revision from proposal and consistentwith past effluentguideline economic achievability analyses, for today’s final rule, EPA determined economic achievability based on primary or direct impacts only. EPA returned to its historical approach of evaluating economic achievability to only primary impacts (here imp acts on airports and airline co-permittees) for today’s final rule because the Agency concluded th at ultimately these entities will be responsible for incurring the costs and associated impact of any addi tional regulation.*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 83 of 147 In the analyses described below, EPA first evaluates the economic achievability of the rule assuming all costs are borne by airports, and the summaries of impacts to airports are based on that assumption. EPA also presents an analysis that shares compliance costs between affected airports and their co-permittee air lines, as applicable. Therefore, impacts to co-permittee airlines presented below are not in addition to the impacts to airports. To the extent that airports share costs with co-permittee airlines according to EPA assumptions, the costs and impacts to airports are reduced. This analysis is described in detail in the rulemaking record DCN XXXX. The following describes the methodology and the results EPA used to evaluate economic impact associated with the two regulatory options c onsidered for today’s fi nal rule, both under the assumption that airports incur 100 percent of comp liance costs, and the as sumption that airports share compliance costs withco-permittee airlines. 1. Cost Annualization The first step in projecting the economic and financial impacts of th e regulatory options rule is cost annualization. EPA projected the cap ital and operating and maintenance costs of the two regulatory options for each airport, then a nnualized those costs over 20 years. The method for estimating each airport’s capital and operati ng costs is described in Section VII.A. EPA used airport-specific interest rates based on recent General Airport Revenue Bonds (GARBs) issues to annualize compliance costs fo r the proposed rule. Based on public comments arguing that EPA underestimated the cost of capital to airports, EPA used a higher real interest rate of 7 percent to annualize airport capital costs for the fina l rule. However, EPA believes many airports will issue tax-exempt GARBs to f und capital expenditures. To the extent that airports use GARBs, it will lower the cost of capital, and reduce impacts to the financial health of the airports. EPA does not assume that airpor ts will be able to fund capital expenditures using*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 84 of 147 Airport Improvement Program (AIP) grants or Passenger Facility Charges (PFCs) because such funds are likely to already be committed to airpor t projects into the foreseeable future. However, to the extent that airports might use AIP or PFC funds for capital expenditu res associate with this rule, it will also lower the cost of capital, a nd reduce impacts to the financial health of the airports relative to what EPA has projected in its analysis. 2. Airport Impact Methodology Because all in-scope airports are nonprofit government or quasi-government entities (e.g., port authority), the effect of an effluent gui deline on airport income statements and balance sheets is not best measured by a traditional closure analysis. Th erefore, EPA chose to examine the financial impacts of the regulatory options us ing two measures. First, EPA compared total annualized compliance costs with airport revenue s. Second, because many airports fund capital expenditures using debt financing, EPA examined the impact of additional debt on each airport’s debt service coverage ratio.
a. Revenue Test EPA's "Guidelines for Preparing Economic Analyses" (2010) recommends the ''revenue test'' as a measure for impacts of programs that directly affect government and not-for-profit entities. EPA finds that the revenue test is appr opriate in this case. The revenue test compares the total annualized compliance costs of each regulatory option with the revenues of the governmental entities. Although th e current Guidelines do not spec ify the use of one and three percent for the revenue test, EPA’s 2000 Guidel ines did, and the Agency’s analysis for the proposed rule followed that guidance; EPA applied the same test here. The Guidelines (2010) suggest evaluating th e affordability of a regulatory option as follows:*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 85 of 147  If total annualized complianc e costs are less than 1 percent of revenues, the option is generally considered affo rdable for the entity;

 If total annualized compliance costs are greater than 3 percent of revenues, the option is generally considered not affordable for the entity. EPA used operating revenue as reported on Form 127 of the FAA’s Airport Financial Reporting Program as the denominator for the reve nue test ratio, and total annualized compliance costs as described under Cost Annualizat ion as the numerator for the ratio. Industry commenters on the proposed rule objected that the revenue test is too simplistic. EPA disagrees, and moreover, industry commenters were unable to provide any alternative test that would more accurately project economic impacts on the industry. Some industry commenters suggested that EPA examine different, more narrowly defined ratios, such as the ratio of compliance costs to aeronautical reve nues, or the incrementa l cost per enplaned passenger. EPA did not choose to replace the revenue test with one of these variants because it determined that total operating revenues are the appropriate denominator for the test: the sole purpose of the airport is to s upport air transportation services. Landside revenues raised through parking, retail, and food concession s, for example, are not designe d to provide a revenue stream to support the provision of a differe nt service or product, but to allow airports to accumulate revenue from non-airline sources. Thus the intent of these revenue streams is also to support the provision of air transportation serv ices and is therefore a compone nt of an airport’s resources relevant to its implementation of these efflue nt limitation guidelines. Furthermore, industry commenters offered no suggestions for alternative thresholds for finding airport impacts, and, in fact, acknowledged that such thresholds do not exist in the case of their recommended incremental cost per enplaned passenger test . EPA did, however, perform several of these*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 86 of 147 alternative tests as sensitivity an alyses and determined that the resulting projections of economic impacts to the industry did not differ significantly from those unde r the revenue test analysis. b. Debt Service Coverage Ratio When creating quasi-governmental agencies such as port authorities, the legislation that created the agency typically incl udes a lower limit on the authority’s debt service coverage ratio (DSCR). Airports owned and operated directly by a state or local govern ment might also have direct limits on airport debt (i f the airport has authority indepe ndent of the city or county government to incur debt). The authority will be in default on its debt if the DSCR falls below the relevant benchmark. A review of Compre hensive Annual Financial Reports (CAFR) for affected airports shows that generally the ratio of net revenues to debt service for any given year cannot fall below 1.25. Therefore, EPA estimated the impact debt financing will have on the post-regulatory DSCR for each airport incurring capit al expenditures under the promulgated rule. From the Airport Questionnaire responses, EP A collected each airport’s current DSCR, and the net revenues and debt service used to calc ulate that ratio. For ai rports that belonged to multi-airport systems under the same ownership, DS CR was reported at the level of the entire system. Therefore, for each re gulatory option, EPA aggregated co mpliance costs for all affected airports in the system, and performed a singl e calculation for the post-regulatory DSCR. Some evidence suggests airports will pass on less than 100 percent of cost s, at least in the short run, if there is concern an airline might withdraw service if the airport increases fees too much. This might occur if the airport has nearby competitors, or if airline finances are fragile. EPA wanted to determine if an airport would be in danger of default on its debt even if it was unable to pass through option costs to its airline customers. Thus, the Agency calculated post-*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 87 of 147 regulatory DSCR in two ways: (1) assuming costs ar e passed through to air lines in the form of higher landing fees, and (2) assu ming no costs are passed through. In the baseline, the DSCR is calculated by divi ding airport net revenues by airport debt service. Assuming 100 percent co st pass-through from airports to airlines, EPA estimated the post-regulatory DSCR of each regulatory option by: (1) assuming zero change in airport net revenues in the numerator (more precisely, EPA assu mes that annual increase in landing fees are exactly equal to incremental annualized deicing costs, thus leaving net revenues unchanged), and (2) adding the annualized value of capital complian ce costs to debt servic e in the denominator. The DSCR decreases even when assuming 100 per cent cost pass-through: although the value of the numerator is unchanged, the denominator incr eases by the amount equal to annualized capital cost, decreasing the value of the ratio. Assuming no cost pass-through from airports to airlines, EPA estimated the postregulatory DSCR by for each regulatory option by : (1) subtracting incremental annual deicing operating and maintenance costs fr om pre-regulatory airport net revenues in the numerator, and (2) adding the annualized value of capital complian ce costs to debt servic e in the denominator. With zero cost pass-through, the numerator in the ratio decreases because incremental O&M costs are subtracted from existing revenues, while the denominator increases because incremental debt is added to existing debt; thus, the DSCR clearly falls. All additional analyses, their methodology, justif ication, and results, ar e presented in the Economic Analysis for Final Effluent Limitati on Guidelines and Standards for the Airport Deicing Category (EA), Do cument No. EPA-821-R-______.*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 88 of 147 3. Co-Permittee Airline Impact Methodology In response to public comment, EPA examined potential economic impacts to airlines that are directly subject to today’s final re gulation: those that are co-permittees on NPDES permits. EPA conducted analyses of impacts to air lines that are co-permittees at certain airports, under the assumption that co-permittee airlines would directly pay a share of the airport’s compliance costs. EPA identified airline co-permittees through EPA’s Airport Deicing Questionnaire, where airports had been aske d to identify all co-permittees. While the questionnaire responses identified co-permittees, th ey did not provide any data or insight into how permit-related compliance costs are currently distributed to, and among, co-permittees, if at all. Although the general outlines of standard contractual relations between airports and airlines can be characterized (see secti on 2.8 of the EA), the inclusion of an airline on the airport’s NPDES permit is not a common practice. In add ition to reviewing information supplied in the questionnaires, EPA searched publicly availabl e information, reviewed comment responses, and inquired with airline representa tives on such relationships. In dustry representatives did not provide EPA with information on these contractua l relationships in the questionnaires or their comments on the proposed rule, nor did they prov ide this information to the Agency in preproposal meetings that were arranged to disc uss the economic methodology of the rule. EPA was unable to gather any specific insight into these relationships and a distribution of compliance costs among the principal NPDES permit holder and its co-permittees. Thus, for purposes of this analysis, EPA assumed compliance costs would be distributed equally among the principal permittee (i.e., airport) and its co-permittee ai rlines. EPA recognizes that some individual airports may share a higher percentage of the co mpliance costs with its co-permittees and others*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 89 of 147 may share a lower percentage. However, for purposes of a national analysis, and with a lack of informative data, EPA finds a 50 percent di stribution assumption to be reasonable. EPA does not separately assign capital costs to airlines and annua lize those costs using airline-specific costs of capital; it seems more likely that with res ponsibility for the physical site, the airport would take the lead and have those costs reimbursed by the co-permittees. Thus, EPA assigned 50 percent of the tota l annualized compliance costs co llectively to the co-permittee airlines. For each model airport with co-perm ittees, EPA needed to determine how to apportion the co-permittee portion of the compliance costs to the individual co-permittees. As explained above, EPA does not have data to determine if co-permittees currently incur any permit compliance-related costs nor, if they do incur th ose costs, how they are distributed among copermittees at individual airport locations. In th e absence of specific information, EPA chose to attribute airport-specific compliance costs to each co-permittee based on its share of total landed weight at the airport. EPA chose this method because ADF usage should be roughly proportionate to the number and type of aircraft an airline typically uses at the airport, and therefore the costs of collec ting and treating that ADF. Sh are of landed weight can be considered a simple summary meas ure that reflects both relative usage and aircraft size. This approach is also consistent w ith how airports typically attrib ute airside operational costs to airlines. EPA then calculated an airline’s tota l compliance costs by summing its airport-specific compliance costs over all airports at which the airline is a co-per mittee. Finally, each airline’s compliance costs are compared to its system-w ide operating revenue, operating profit, and net income. The comparison of one year’s average annuali zed compliance costs with operating profit and net income is consistent wi th a typical economic impact analysis. In a typical economic*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 90 of 147 impact analysis, EPA would project the affectedentities’ discounted compliance costs and cash flow over the period of analysis. If an entity’s pre-regulatory discounted cash flow is positive, and its post-regulatory discounted cash flow is ne gative (i.e., projected pr e-regulatory discounted cash flow less discounted compliance costs), the entity would be proj ected to close as a result of the effluent guideline. EPA th en typically examines economic achievability by looking at the total number of closures relative to the total numbe r of in-scope companies. In this case, if average compliance costs in one year exceed averag e operating profit or net income for that year (i.e., the ratio of compliance cost s to operating profit or net income is greater than 100 percent), the airline can be projected to “close” as a result of the effluent guideline. However, such an analysis is problematic for airlines, for a number of reasons. First is the problem of “baseline closures.” A baseline closure is an entitywith negative income prior to the promulgation of the effluent guideline. A ba seline closure cannot be evaluated on the basis described above because the logic of that anal ysis requires that the entity’s pre-regulatory income be greater than zero. As amply documented in the Economic Analysis document (and updated in DCN XXXX), the last decade has been financially difficult for the airline industry, and approximately half the U.S.-flag airlines incurring compliance costs as co-permittees under normal circumstances would be ca tegorized as “baseline closures ” and could not be analyzed by this standard. Second, airlines have many options they can undertake in response to increased costs, short of going out of business. For example, ai rlines have the option to change service to a particular airport by increasing fares, decreasing service freque ncy, using different (typically smaller) aircraft, eliminating destin ations flown to directly from that airport, or even eliminating service altogether to that airport.*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 91 of 147 To address the baseline closur e issue, EPA included airline operating revenue as a third measure against which compliance costs can be compared, along with operating profit and net income. The purpose of using operating revenue is solely because such a large proportion of the airline industry cannot be evaluated due to negative baseline ope rating profit and/or net income: 23 of 46 co-permittee airlines with financial da ta available have nega tive baseline operating profit, and 25 of 46 have negative baseline net income. Furthermore, classifying an entity as a “baseline closure” does not mean it will necessarily close; a business entity might earn negative operating profit or net income at some point in its fi nancial history without closing permanently, and this appears to be particular ly prevalent in the ai rline industry (see, for example, the Industry Profile in the Economic Analysis document). Ra ther than ignore roughly ha lf of all co-permittee airlines, EPA chose to evaluate them using the ratio of compliance cost s to operating profit to determine if the rule imposes costs that can be characterized as “relatively small.” The primary drawback of using operating revenue to measure economic impacts is that , unlike with operating profit or net income, there is no obvious thresh old that determines what is economically achievable. To respond to the issue of changing service levels at an airport, it would also be informative to perform, if possible, a closure anal ysis at the route level fo r each airline’s routes associated with airports. However, EPA does not have available, nor could it reasonably obtain, airline financial data at either the route level or the airport level. Therefore, EPA must evaluate impacts to co-permittee airlines based on the onl y level at which airline financial data are available: their system-wide operations.*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 92 of 147 D. Results of Impact Analysis 1. Results of Airport Impact Analysis a. Revenue Test Impact Results As noted in the previous section, EPA exam ined a number of alte rnative measures of economic impacts for airports in response to pub lic comments on the proposed rule. However, EPA found none of these alternative approaches to be preferable. None of them provided a clear dividing line for determining what impacts might or might not be economically achievable for airports. That is, even if EPA selected one of industry’s measures, EPA would still have to determine some threshold that distinguishes imp acts that are economically achievable from those that are not; industry did not provi de such thresholds with their preferred measures, and for one measure specifically stated they did not know what the appropriate threshold would be. Nevertheless, EPA did perform sensitivity analyses to determine what effect the use of these alternative measures might have on our conclusions on economic achie vability of the final rule. Our sensitivity analyses found th at using these alternative meas ures would not substantively change the overall results on the final rule’s economic achievability. The results of these alternative analyses are not presented in this pr eamble, but are included in the EA as sensitivity analyses. Table VIII-2 shows the projec ted financial impact of the regulatory options considered for today’s rule. Under Option 1, airports would incur $49.4 million in annualized costs (7 percent real interest rate), a nd 5 of the 198 airports (2.5 percen t) are projected to incur costs exceeding 3 percent of operating revenue. One hundred seventy-six of the 198 airports subject to BAT (87 percent) are projected to incur annua lized compliance costs composing less than 1 percent of operating revenue. Under Option 2, ai rports would incur $78. 4 million in annualized*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 93 of 147 costs (7 percent real interest rate), and 9 of the 198 airports (4.5 percent) are proj ected to incur costs exceeding 3 perc ent of operating revenue. One hundred seventy-two of the 198 BAT airports (87 percent) are projec ted to incur annualized compliance costs composing less than 1 percent of operating revenue. Five airports do no t have airport-specific financial data because they are part of Alaska’s Rural Aviation Sy stem, and therefore could not be analyzed. Table VIII–2. Financial Impacts of BA T Options on Airports that Deice [2006 $ millions – 198 airports (weighted)]
Option Total annualized costs Number of airports with ratio of annualized compliance costs to operating revenue of: Less than 1% Between 1% and 3% Greater than 3% Not analyzed [a] 1 $49.4 176 13 5 5 2 [ b ] $78.4 172 13 9 5 [a] Airports incurred compliance costs but ow ned by the state of Alas ka; financial impacts could not be analyzed because Alaska does not track revenue data for these airports. [b] Selected option.
b. DSCR Impact Results For multi-airport systems, the DSCR must be evaluated at the level of the owner, aggregating compliance costs incurred by all syst em airports. Thus, EPA analyzes entities owning single airports separately from multi-ai rport systems. Under today’s final rule, among owners of single airports, only one is projected to be in danger of default on its debt even if 100 percent of compliance costs are assumed to be passe d through to airlines; tw o additional airports are in danger of default if they are constrained intheir ability to pass through costs to airlines (see Table VIII–3). EPA identified 9 multi-airport systems owning 21 airports projected to incur costs under the final rule, and analyzed costs for the 8 systems with data available. For the 8 airport systems owning 16 BAT airports for whic h the debt service coverage ratio (DSCR) analysis could be performed, the re sults presented in Table VIII–4 s how that today’s final rule is*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 94 of 147 projected to have no impact on th e ability of airport authorities to finance debt. EPA did not analyze impacts to the DSCR for the Alaska Ru ral Aviation System (1 system owning 5 BAT airports) because Alaska does not use debt financing to fund this system. Table VIII–3. Impact of Financing BA T Options on Airport Debt Service Coverage Ratio – Single Airport Owners [172 airports (weighted)] Option Incur costs [a] Not analyzed [a] Owners with pre-regulatory DSCR > 1.25 & post-regulatory DSCR < 1.25

100% Cost Pass Through 0% Cost Pass Through 1 172 59 1 2 2 [ b ] 172 59 2 3 [a] Of 198 airports (weighted), each of the 172 was estimated to be both subject to BAT and the only airport controlled by its owners hip. These columns represent the number of those 172 airports projected to incur cost s under each option, and of those airports incurring costs, the number that cannot be an alyzed due to lack of sufficient data. [b] Selected option.

Table VIII–4. Impact of Financing BAT Option s on Airport Debt Service Coverage Ratio – Multi Airport Owners [9 airport authorities owning 21 in-scope airports (unweighted) [a] ]

Option Incur costs [b] Not analyzed [b] Owners with preregulatory DSCR > 1.25 & post-regulatory DSCR < 1.25 Owners Airports Owners Airports 100% Cost Pass Through 0% Cost Pass Through 1 9 21 1 5 0 0 2 [c] 9 21 1 5 0 0 [a] Some airports that are part of a multi-airport system have a sample weight greater than one; because airports were not sampled based on owne rship patterns it is not appropriate to use the sample weight in this analysis; the results cannot be extrapolated to represent any airports and their ownership patterns other than themselves. [b] EPA found 9 distinct airpor t authorities owning 21 airports that were determined to be subject to BAT. These columns represent the number of airport owne rs and the number of airports they owned that are pr ojected to incur cost s under each option, and of those owners and airports incurring costs, the numbe r that cannot be analyzed due to lack of sufficient data. [c] Selected option.*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 95 of 147 The DSCR analysis projects that two airports (of 59 analyzable airports) owned by single airport authorities, a nd no airports owned by multi-airport authorities (eight authorities owning 16 airports subject to BAT), are at risk for default on their debtassuming 100 percent cost passthrough from airports to airlines. One additiona l airport is at risk for default assuming zero compliance costs are passed through from airports to airlines. Therefore EPA determined that this analysis also demonstrates thatthe rule is economically achievable. Moreover, EPA’s analysis likely overestimates the impact of the rule on airports’ ability to service debt. Of the two air ports projected to be at risk of default under the 100 percent cost pass-through assumption, one completed installa tion of a deicing pad after the survey was submitted, and therefore, in reality, would incur significantly lower costs than the projected compliance costs. The second airport result may be an artifact of how th at airport’s rates and charges are calculated: the ai rport’s 2004 DSCR was reported as exactly 1.25, and therefore, even though its projected annuali zed compliance costs are less than $10,000, the model predicts it is in danger of default. However, we judge it unlikely that an airport with 11 million passenger enplanements, operating revenues exceeding $80 million, and long-term bond ratings of “A” from Standard and Poor’s and Fitch Ratings, an d “A2” from Moody’s Investor Services in 2004 will default on its debt because of $1 0,000 in annualized compliance costs. Finally, an airport will not necessarily de fault on its debt should the airport’s postregulatory DSCR as measured in this analysis fa ll below the 1.25 threshold. Rather, this should be taken as an indication that the airport will potentially be in seri ous financial distress if it issues additional debt but does nothing to strengthen its financial cond ition. This is essentially a warning sign that the airport must undertake acti on to avoid default: rates and charges could be raised by a larger amount, debt might be restru ctured, and airports may have opportunities to pay*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 96 of 147 for capital expenditures without incurring debt (e.g., “pay-a s-you-go” funded through rates and charges or passenger facility charges (PFC)). c. Impacts to Alaska’s Rural Aviation System Five airports operated by the State of Alaska could not be analyzed using the revenue test or the DSCR as presented above. These airports are part of Alaska’s Rural Aviation System (RAS) which is not a self-supporting system; Alaska has determined these airports must remain open despite financial loses to provide access to otherwise isolated rural communities. EPA evaluated economic impacts to these air ports separately, as described below. Alaska operates two airport systems. The Al aska International Airport System (Ted Stevens Anchorage International Airport and Fa irbanks International Airport) is a major enterprise fund of the State of Alaska, and consider ed to be self-sufficient; in short, the Alaska International Airport System operates in the same manner as most other multi-airport authorities in the United States. Alaska’s second system, the RAS, consists of 256 rural airports, is not a self-sufficient government unit, and loses money every year. EPA determ ined that five RAS airports would be subject to BAT requirements (Bethel, Ketchikan Inte rnational, Sitka Rocky Gutierrez, Nome, and Ralph Wien Memorial). Due to the nature of transportation in Alaska, it is vital that these airports remain in operation despite not being profitable; approximately 82 percent of Alaskan communities are not served by roads, and these communities rarely have a practical alternative to air transportation fo r access (DOT website c onvert to DCN XXXX). According to the Alaska Department of Tran sportation and Public Facilities (DOT&PF), RAS airports “are funded through a combination of user fees, state, local, or tribal funds, and federal funds.” However, the rural airp orts have very limited opportuni ties for generating revenue; in 2004 revenues from airport users, concessions, a nd leasing of airport property comprised less*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 97 of 147 than 17 percent of the cost of operating the system (Maggard, 2008 [convert to DCN XXXX]). The system is largely reliant on state subsidies to pay O&M costs at thes e airports. Therefore EPA separately evaluated impacts to the RAS. EPA estimated compliance costs for the five RA S airports subject to BAT. EPA used the estimated yearly contribution of $23 to $24 million by the State of Alaska to cover the operating costs of the RAS (DCN AD05081) as a proxy for RAS operating revenues for the purpose of measuring economic impacts. This is an unde restimate of RAS revenues because it does not account for the unknown revenue stream from other sources. Under the selected BAT option in the final rule, projected compliance costs for th e five RAS airports to gether total $69,000, which compose 2.94 percent of the State’s contribution to airport operations. EPA therefore determined that because compliance costs to the RAS compose less th an 3 percent of the system’s revenues, the rule is ec onomically achievable to the RAS. Based on all of the above and as further doc umented in the record, EPA has determined that the final rule is economically achievable for airports. 2. Results of Co-permittee Airline Impact Analysis EPA determined that 27 airports subject to BAT and incurring costs listed 75 individual airlines as co-permittees. Forty-nine of these co-permittee airlines were U.S.-flagged, while the remaining 26 were foreign-owned. On average, eachof the 49 U.S.-flagged air carriers was a copermittee at 5 airports, with a range of co-permitting of between 1 to 21 airports. Under an assumption of a 50:50 split of compliance costs betw een airports and co-permittee airlines, these 49 carriers would incur $18.8 million in annualized compliance costs, and the 26 foreign-flag carriers would incur $0.7 million.*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 98 of 147 Forty-six of the 49 U.S. co-permittee airlines have financial data available. Twenty-three co-permittees have positive baseline operating prof its, and 21 have positive baseline net income, and therefore are eligible to be analyzed using these metrics. EPA projected that none of these airlines will incur costs exceeding 3 percent of ope rating profit or net income under either option 1 or option 2. This is well short of the 100 perc ent threshold that woul d indicate a definitive closure. Furthermore, none of the 46 airlines we re projected to incur compliance costs exceeding 0.25 percent of operating revenues un der option 1, and only 1 airline was projected to incur costs exceeding costs 0.25 percent of revenues under option 2. To put this in c ontext of other costs borne by the airlines, EPA’s analysis shows that co -permittee airlines will incur costs from this rule that create on average 0.029 percent of opera ting revenues; while thes e airlines on average spend 26 times that amount on advertising (0.7 6 percent of operating revenues), and 35 times that amount on food (1.02 percent of operating re venues). Therefore EPA judged these airline co-permittees are not significantly impacted by the rule. Finally, to the extent that 50 percent of ai rport compliance costs are shared with copermittee airlines, impacts to air ports are reduced as measured by the ratio of compliance costs to operating revenue. EPA projects 5 airports incur costs exceeding 3 percent of revenues under the promulgated option using the assumptions of the co-permittee airline analysis. Assuming no costs are shared with co-permittee airlines, EP A projected 9 airports incur costs exceeding 3 percent of revenues under this option. 3. Economic Achievability Based on the analyses presented above, EPA has determined that both Option 1 and Option 2 are economically achievable. EPA find s that the promulgated option is economically*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 99 of 147 achievable both when airports are assumed to in cur 100 percent of compliance costs, and when airports and their applicable airline co-permittees are assume d to share compliance costs. Under previous rulemaking efforts that di rectly impose compliance costs on government agencies, EPA used the revenue test to evaluate impacts to these agencies; when projected compliance costs exceed 3 percent of operating re venues, the rule is judged to be unaffordable for a facility. As shown in Table VIII–2, only 9 airports, which are less than 5 percent of the airports subject to BAT, are projected to incur costs exceeding 3 per cent of operating revenue when airports are assumed to incur 100 per cent of compliance costs. EPA used several conservative assumptions in evaluating impacts to airports: costs were annualized using a real 7 percent interest rate, which is si gnificantly higher than airports typically pay for debt financing. At the 7 percent real interest rate, EPA demonstrat ed that airports’ abilit y to service debt would not, in general, be negatively affected by the rule . EPA also did not take into account airports’ ability to access other funding for capital expenditure, such as AIP grants or PFCs. Also, EPA performed its analysis of airport impacts without distributing any costs to co-permittee airlines. As such, the estimates of impacts at airports with co-permittees may be overstated. With respect to airlines that are NPDES co -permittees, none of these airlines are shown to incur a demonstrable impact under either optio n on three airline income measures: operating revenue, operating profit, or net income. Therefore, EPA finds the costs to be economically achievable for co-permittee airlines for either of the options considered fo r today’s final rule. Finally, EPA also assumed compliance costs would not be passed th rough to airlines and/or their passengers in the form of higher ra tes and charges. (As explained above, EPA did assume costs would be shared by co-permittee air lines.) This is a conservative assumption and EPA believes that airports and, ulti mately, airlines will use some or all of the above to reduce the*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 100 of 147 cost and impact of the rule, which is further s upport for EPA’s conclusion that today’s final rule is economically achievable. E. Economic Impacts for New Sources EPA has determined that the NSPS in the fina l rule would not impose a barrier to entry. Although few greenfield airports (a irports built on undeveloped land or land not previously used for aviation) have been developed with deicing pads, EPA obtained data for Denver International Airport, which incorporated deic ing pads. Information from Denve r demonstrates that the CDPs comprised 4 percent of the cost of building a ne w airport, and did not po se a barrier to entry (DCN XXXX). However, the building of ma jor greenfield airports has become a relatively rare occurrence. Denver International opened in 1995, but new, major airports built prior to Denver predate it by 20 or more year s: Dallas-Fort Worth, which opened in 1973, and George Bush International in Houston, Texas and Washingt on Dulles, which opened in the 1960s. Conversion of ex-military airports appears to be a much mo re common source of sites for cities seeking to increase air transportation access (e.g., Orlando International). EPA re viewed FAA’s National Plan of Integrated Airport Systems (NPI AS) reports published between 2002 and 2010, and found that the development of any new commercial service airports is relatively rare, but a smaller commercial service greenfield airport is more likely to be built than a major one. In 2002 FAA expected 125 airports to open within the next five years, none of which were commercial service airports. Sinc e then, a new commercial service airport in Panama City, FL opened in May 2010, and St. George, UT opene d in January, 2011. The opening of a third commercial service airport in Peotone, IL that was expected by 2015 currently appears to be on hold (Chicago-Tribune, 2010/DCN XXXX). Cities such as Bow ling Green, KY, Hazleton, PA,*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 101 of 147 and Las Vegas, NV have been performing needs assessment and feasibility studies since before 2002, but as of 2010 no solid plan s appear to have emerged. Therefore, EPA wanted to examine a broader set of airport characteristics to account for new smaller commercial airports that might be subject to new source requirements. Based on incomplete data published in the NPIAS, EPA assumes that the St. George airport, with a planned service level of 55,000 annual enplanem ents, cost a minimum of $70 million. The Panama City airport, with a planned servic e level of 225,000 annual enplanements, appears to have cost a nominal $200 million in the same peri od. Because eligibility for the ELG is partly based on non-propeller driven ai rcraft departures, EPA estimat ed departures for these two airports based on expected annual enplanements . Among the 198 existing airports subject to BAT requirements, only 14 in the lower 48 states have fewer than 100,000 annual enplanements, and only 6 have fewer than 60,000 annual enplanemen ts. Thus, EPA believes an airport like St. George might be too small to be subject to the re quirements of this effluent guideline. However, a new airport the size of the Panama City airport might be subject to new source requirements. Due to its location, EPA does not expect that the Panama City airport itself will be subject to NSPS requirements. However, this airport is the only airport EPA found with data available on construction costs, and is of suff icient size that it might be subj ect to the ELG were it located further north. Therefore, EPA used Panama City’s cost data to represent a new, relatively small airport that is subject to NSPS. Based on CDPs constructed at existing airports , EPA estimated the average capital cost of constructing a CDP of appropriate size to meet the airport's operating requirements as total CDP capital cost divided by average a nnual departures. Thus, the aver age capital cost of a CDP is $515 per average annual departure (DCN XXXX). In addition, EP A estimated annual departures*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 102 of 147 at Panama City; existing comme rcial service airports with annual enplanements between 200,000 and 300,000 average about 32.3 passengers per depart ure, thus EPA expects Panama City will average somewhat less than 7,000 departures per y ear. Therefore, EPA estimates that should an airport the size of Panama City need to build a CDP, then the capital cost of that pad will be about $3.6 million, or about 1.8 percent of the initial cost of the airport. Furthermore, CDPs integrated into airport traffic patterns from the time of construction can be planned to minimize impacts on flight operations. Therefore, with CDPs expected to cost from 1.8 percent to 4 percent of the cost of building a new airport, EPA has determined th at the NSPS in the final rule would not impose a ba rrier to entry. F. Cost and Pollutant Reduction Comparison Today’s final rule is expected to redu ce COD and ammonia loads by 33 million pounds at an annualized cost of $78.0 million, for a co st of $2.37 per pound of pollutant removed. Table VIII-5. Pollutant Removals, Costs and Cost-Reasonableness of BAT Options for Airports that Deice (weighted) Option Total pollutant Removals (million lb) Total annualized costs (2006 $ mil.) Cost/lb pollutant removed 1 30.2 $49.4 $1.64 2 [a] 33.0 $78.4 $2.37 [a] Selected option. EPA has reviewed the relative cost per pound of pollutants removed in previous effluent guidelines and has found that the cost per pound presented in today’s final Airport Deicing rule is similar to or less expensiv e than many guidelines promulgate d to date including: Aluminum Forming (40 CFR part 467), $2.42/lb; Landfills (40 CFR part 445), $15.00/lb; and Waste Combustors (40 CFR part 444), $38.83/lb.*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 103 of 147 G. Small Business Analysis The Regulatory Flexibility Act (RFA), as amended by the Small Business Regulatory Enforcement Fairness Act of 1996 (SBREFA; herein after referred to as RFA), acknowledges that small entities have limited resources, and make s it the responsibility of regulating federal agencies to avoid burdening such entities unnecessarily. The ultimat e goal of RFA is to ensure that small entities do not incur disproportionate adverse economic imp acts as a result of a regulation. The first step in this process is to determine the number and type of small entities potentially affected by the regulation. The RFA (5 U.S.C. 601) defines three types ofsmall entities: small business, small notfor-profit organization, and small governmental juri sdictions. Airport owne rship is composed of states, county, city governments, and single and multi-purpose port authorities. Single and multi-purpose port authorities are quasi-governmental agencies created by legislation to maintain and operate airports, shipping ports , and other government-owned f acilities such as bridges. The RFA defines a small government entity as governments of cities, counties, towns, townships, villages, school districts, or special districts, with a population of less than 50,000. After matching each airport-owning governmental en tity with its population, EPA estimates that:

 72 airports are owned by small government entities

 20 airports owned by small government entiti es are subject to BAT requirements in today’s final rule. Although many Alaskan airports are relatively small when measured by service level, most of these airports are owned by the St ate of Alaska and therefore ar e not considered small for the purposes of the RFA; 10 of the 11 surveyed Alas kan airports are not sm all by this standard.*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 104 of 147 One of the 20 BAT airports owned by small gove rnment entities is expected to incur total annualized compliance costs exceeding thr ee percent of airport operating revenues. Table VIII–6. Financial Impacts of BAT Options on Small Airports that Deice [a] [2006 $ millions – 20 airports (weighted)]
Option Total annualized costs Number of airports with ratio of annualized compliance costs to operating revenues of: Less than 1% Between 1% and 3% Greater than 3% Not analyzed [b] 1 $0.34 19 0 1 0 2 [c] $0.34 19 0 1 0 [a] An airport is considered small if the govern mental entity that owns the airport serves a region with less than 50,000 people. [b]Airports incurred compliance costs but financia l impacts could not be analyzed due to lack of airport revenue data. [c] Selected option.
EPA found 18 airlines that are co-permittees atBAT airports are small by SBA standards; 16 of these airlines had available financial data. None of the 16 small co-permittee airlines were projected to incur compliance costs exceeding 1 percent of operating revenues under either option 1 or option 2; 15 of the 16 are projected to incur costs that are less than 0.25 percent of operating revenues, and the 16th ai rline is projected to incur costs less than 0. 5 percent of operating revenues under option 2. When compari ng compliance costs with operating profits and net income, 8 small airlines had positive base line operating profits and net income, and none are projected to incur costs ex ceeding 3 percent of either measure under option 1 or option 2. Again, these are well short of the 100 percent thre shold that would indicate a definitive closure. One airport with airline co-permittees on its NPDES permit is small by SBA standards. This airport’s projected compliance costs exceed 3 percent of airport reve nue if it does not share compliance costs with its co-perm ittee airlines. Its costs do not ex ceed 3 percent of revenue if it does share compliance costs withits co-permittee airlines.*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 105 of 147 EPA concludes that small entities are not di sproportionately affect ed by this effluent limitations guideline. Only a fraction of in-sco pe airports are small by SBA standards, and only one of those airports is projected to incur costs exceeding 3 percent of operating revenues. Furthermore, this airport is not projected to ex ceed that threshold if 50 percent of its compliance costs are shared with co-permittee airlines. EP A also concludes that small airlines are not disproportionately affected by the rule. Airlines are only subject to the rule if they are copermittees on an airport's NPDES permit. Ei ghteen co-permittee airlines are small by SBA standards, 16 of which have financial data avai lable. As described abov e, analysis of these airlines shows that under the assu mption of 50:50 cost sharing withaffected airports, none come close to a threshold that i ndicates a significant impact to their financial situation.

IX. Environmental Assessment A. Environmental Impacts EPA has evaluated environmental impacts asso ciated with the disc harge of wastewater from airport deicing activities (Environmental Imp act and Benefit Assessment for Final Effluent Guidelines and Standards for the Airport Deicin g Category (EIB)). As discussed in Section VII.B., deicing wastewater discharges can in crease the loadings of multiple pollutants to receiving surface waters. The most widely recognized pollutant from deicing activity is oxygen-demanding material, measured as either COD or BOD 5 . All primary ingredients in both aircraft and airfield deicers exert oxygen demand. Propylene glycol and ethylene glycol are th e primary ingredients in aircraft deicers. Acetate salts, formate salts, propylene glycol, ethylene glycol and urea are the primary ingredients in airfield de icers. Propylene glycol and ethyl ene glycol, in particular, exert*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 106 of 147 extremely high levels of oxygen demand when th ey decay in the environment. Acetates, formates, and urea exert lower, though s till significant, levels of oxygen demand. Acetate or formate salts, the primary ingredie nts in many airfield deicers, also contain potassium or sodium. Potassium and sodium can raise overall salinity levels or cause ion imbalances in surface waters. Urea, another prim ary airfield deicer ingr edient, decomposes in water to produce ammonia, a toxic compound, and n itrates, a nutrient polluta nt that can increase the incidence of organism blooms in surface waters. Aircraft and airfield deicers also contain additives in additi on to the primary ingredients. These additives serve a variety of purposes such as reducing fluid surf ace tension, thickening, and fire and corrosion inhibition. Because dei cer manufacturers consid er the identity and quantity of additives in their formulations to be proprietary information, EPA was unable to obtain complete information on the nature and use of these additives. EPA was able to obtain some limited in formation through various public sources, and identified several additives with toxic properties. Thes e include nonylphenol ethoxylates, alcohol ethoxylates, triazoles, polyacrylic acid and others. Although toxic, these additives directly influence the effectiveness and safety of deicing and anti-ici ng formulations and are therefore essential components. Because deicer formulations change periodically, some of the additives EPA identified may not be present in current formulations. Deicing fluid manufacturers are also investig ating ways to formulate deici ng and anti-icing compounds with the use of less toxic, or non-toxic, additives Airports in the United States discharge deic ing wastewater to a wi de variety of water body types including streams, rivers, lakes and es tuaries. Many airports discharge deicing wastewater to small streams with limited waste dilution and assimilation capacities. Impacts*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 107 of 147 from deicing wastewater discharges have been documented in a variety of surface waters adjacent to or downstream of a number of airp orts in the United States. Some locations experienced acute impact events, whereas other lo cations have chronically degraded conditions. Observed impacts to surface waters include both physical and biological impacts. Some surface waters have been listed as impaired under sec tion 303(d) of the CWA because they do not meet applicable state water quality standards. Physi cal impacts include elevated levels of glycol, salinity, ammonia, and other pollutants; depres sed oxygen levels; foaming; noxious odors; and discoloration. Biological impacts include reduc ed organism abundance; fish kills; modified community composition; and re duced species diversity. Deicing wastewater discharg es have impaired both aquati c community health and human uses of water resources. Available documenta tion indicates multiple cases of hypoxic conditions and severe reduction in aquatic organism leve ls in surface waters downstream of deicing wastewater discharge locations. Documented human use impacts include contamination of surface drinking water sources, contamination of groundwater drinking water sources, degraded surface water aesthetics due to noxious odors and discolored water in residential areas and parklands, and degradation of fisheries. B. Environmental Benefits EPA has evaluated environmental benefits asso ciated with today’s final rule to reduce the discharge of pollutants from airport deicing activities. This assessment is described in detail in the EIB. The final rule BAT requirement is e xpected to decrease COD discharges associated with airport deicing activities by approxima tely 28.6 million pounds per year. The BAT requirement is also estimated to reduce amm onia discharges by 4.4 million pounds. The rule will also reduce the loadings of toxic additives in aircraft deicer formulations to the environment.*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 108 of 147 The decline in pollutant loadings will reduce environmental impacts to surface waters adjacent to and downstream of these airports. A variety of surface waters have improved in quality after reductions in deici ng pollutant loadings. Document ed improvements have included abatement of noxious odors, decline in fish kill frequency, and partial re covery of community species diversity, and organism a bundance in small water bodies. Today’s final rule will decrease pollutant loadings to multiple surface waters currently listed as impaired under CWA s ection 303(d). The rule will also reduce pollutant loadings to surface drinking water intakes, park s, and residential areas downstream of airports. Groundwater aquifers will also benefit. See the EIB for additional details.

X. Non-Water Quality Environmental Impacts Sections 304(b) and 306 ofthe Clean Water Act require EPA to consider non-waterquality environmental impacts (including ener gy requirements) associ ated with effluent limitations guidelines and standards. To complywith these requirement s, EPA considered the potential impact of the colle ction and treatment technologi es on energy consumption, air emissions, and solid waste generation. While EPA prepared formal analyses only for technologies associated with t oday’s BAT requirements, given the similarities between the two regulatory options evaluated toda y, it anticipates that Option 1 would produce similarly minimal non-water quality impacts. For a more in-depth analysis of these non-wate r quality impacts, see the Technical Development Document. A. Energy Requirements Net energy consumption considers electrical requirements for pumping ADFcontaminated stormwater from co llection areas to storage, electrical requirements for operating*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 109 of 147 the anaerobic fluidized bed (AFB) bioreactors, and fuel requirements for glycol collection vehicles (GCVs). EPA estimates that the total incremental el ectrical usage to pump ADF-contaminated stormwater into storage tanks would be appr oximately 1.2 million kilowatt hours per year (kWh/yr). EPA also developed a relationshi p between electrical use and chemical oxygen demand (COD) removal by the AFB bioreactors based on information provided by Albany International (ALB) airport. Using the inform ation from ALB, EPA estimated the electrical requirement for COD removal as approximately 1.3 kWh/lb COD removed. Using this unit rate, EPA estimated total electrical requirements to re move COD for the final rule to be a maximum additional 22 million kWh/yr. EPA also analyzed fuel use by GCVs co llecting ADF-contaminated stormwater. EPA used Airport Questionnaire data for diesel fuel costs for GCVs, and then estimated an average diesel fuel use based on the unit cost for diesel fuel of $2.07/gal. 2 EPA then estimated annual fuel usage per gallon of applied ADF to be 0.08 gal/gal ADF applied. Using this relationship, EPA estimated that the total incremental consumpti on of No. 2 diesel fuel, at all airports subject to BAT and installing additional collection equipment, to be 354,500 gallons per year. EPA compared incremental diesel fuel use by GCVs as a result of the rule to diesel fuel use on a national basis. Approximately 25.4 million gallons per day of No. 2 diesel fuel was consumed in the United States in 2005. The diesel fuel requirement associated with this rule is less than 0.004 percent of the annual amount of diesel fuel consumed.

2 This diesel fuel price was the aver age reported by the Energy Informatio n Administration for the 2004-05 winter season, the same period that EPA is analyzing for airport deicing activity.*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 110 of 147 Additionally, as EPA assumes that aircraft operations will not be delayed as a result of today’s rule and that deicing will occur at the gate s, there is no increase in jet fuel consumption associated with today’s rule. B. Air Emissions Additional air emissions as a result of the rule could be attributed to added diesel fuel combustion by GCVs collecting ADF-contaminated st ormwater and from anaerobic treatment of ADF. Emissions from these sources are discusse d below. As EPA assumed no increase in jet fuel consumption, there is no increase in emissi ons from aircraft operations associated with today’s regulation. 1. Emissions from GCV Collection As discussed in Section XI.A above, EPA c onservatively estimated that GCVs collecting ADF-contaminated stormwater at airports will consume an additional 354,500 gallons per year of No. 2 diesel fuel. To estimate air emissions re lated to combustion of No. 2 diesel fuel in the internal combustion engines on GCVs, EPA us ed published emission factors for internal combustion engines. The Agency selected emissi on factors for gasoline and diesel industrial engines because EPA assumed this class to be a mo re representative population of engines. To estimate emissions from the GCVs, EPA first c onverted the additional 354,500 gallons of diesel fuel to million British Thermal Units (MMBtu) and then applied the appropriate emission factors. The calculated annual emissions indicate that an a dditional 4,070 tons per year of carbon dioxide (CO 2 ) will be emitted from GCVs combusting additional diesel fuel to comply with the rule. Carbon dioxide is the primary greenhouse gas attribut ed to climate change, and the 4,070 additional tons per year that would be associ ated with the rule is very small relative to other sources. For example, in 2006, industria l facilities combusting fossil fuels emitted 948*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 111 of 147 million tons of CO 2 equivalents. An additional 4,070 tons per year from GCVs is less than a 0.0004 percent increase in the overall CO 2 emissions from all industrial sources. 2. Emissions from AFB Treatment Systems Anaerobic digestion of glycols found in ADF -contaminated stormwater generates biogas containing approximately 60 per cent methane and 40 percent carbon dioxide. Airports installing AFBs for treatment of ADF-contaminated stormwater are expected to burn a portion of the gas in on-site boilers in order to maintain reactor te mperature. The remainder of gas can be either combusted in a microturbine for electricity gene ration or flared. Regardless of the combustion technology, nearly all biogas generated by AFBs is converted to carbon dioxide, the primary greenhouse gas. EPA calculates a maximu m 3,730 additional tons per year of CO 2 generation for 40 percent ADF collection, which is very sma ll relative to other sour ces. For example, in 2006, industrial facilities combusting fo ssil fuels emitted 948 million tons of CO 2 equivalents. An additional 3,730 tons per year of carbon diox ide from AFB treatment is less than 0.0004 percent of the annual industrial ca rbon dioxide emissions nationwide. C. Solid Waste Generation AFB bioreactors will generate sludge that will require disposal, probably in an off-site landfill. To estimate annual sludge generation by the AFB bioreactors that may be installed at airports to treat ADF-contaminated stormwater, EPA first estimated the potential COD removal for the collection and treatment scenarios and th en applied published anaerobic biomass yield information to estimate total sludge generation on a national basis. The biomass yield calculation, which simply multiplies the COD removal by the yield, is a rough method of estimating sludge generation and does not account for other factors such as degradation or inorganic material (e.g., AFB medi a) that may be entrained into the sludge. However, this*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 112 of 147 method does provide an order of magnitude estimate of sludge generation that can be compared to other types of common biol ogical treatment systems to dete rmine if AFB sludge generation would be unusually high at airports treating ADF-contaminated stormwater. To provide some perspective on the potent ial total amount of biomass produced annually by the AFB biological reactors tr eating ADF-contaminated stormwater, EPA compared the most conservative biomass generation estimate with it s national biosolids estimates for all domestic wastewater treatment plants thr oughout the United States. Appr oximately 8.2 million dry tons of biosolids were produced in 2010. EPA estim ates that AFB bioreactors treating ADFcontaminated stormwater will increase bi osolids generation in the United States by approximately 271 dry tons/year or less than 0.003 percent of dry ton biosolids produced in the U.S. in 2010. Based on this evaluation of non-water qualityimpacts, EPA concludes there are no nonwater quality impacts associated with today’s final rule.

XI. Regulatory Implementation A. Relation of ELGs to NPDES Permits Effluent guidelines act as a primary mechanis m to control the discharge of pollutants to waters of the U.S. Today’s final rule will be applied to airports through incorporation in individual or general NPDES permits issued by EPA or authorized states under section 402 of the Act. The Agency has developed the limitations for this final rule to c over the discharge of pollutants from this point source category. In ad dition, if state water qua lity standards or other provisions of state or federal law require limits on pollutants not covered by this regulation (or*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 113 of 147 require more stringent limits or standards on covered pollutants to achieve compliance), the permit authority must apply those ef fluent limitations or standards. For individual permits, ELG provisions are typically incorporated when those permits are renewed, although permit authorities may requi re modification upon promulgation. EPA will revise its Multi-Sector General Permit to include the airport deicing provisions when the permit is renewed, and authorized states will proceed likewise with th eir respective general permits. B. Applicability Date The general applicability date for today’s final ru le is [insert date that is 30 days after the date of publication in the Federa l Register]. However, in re sponse to comments received, EPA has added a provision at § 449.1(b) to extend the date of applicab ility of the ADF collection and discharge requirements for existing airports to provide an additional three years to comply, in order to arrange for financing a nd/or construction of capital improve ments. Airports that have permit renewal dates more than three years from th e general applicability date do not receive this extension. C. Demonstrating Compliance with the ADF Collection Requirement The ADF collection requirement differs from traditional end-of-pipe effluent limitations with regard to demonstrating compliance. Co mpliance with the collection requirement may not always be determined through end-of-pipe samp ling and analysis. Additionally, the amount of ADF available for collection can vary depending on the weather and icing conditions at the time of application. As in the proposed rule, today’s final rule provides three procedures for selection by the permittee, for demonstrating compliance with the ADF collection requirement. To utilize the first procedure, at §449.20 (a)(1) for BAT and §449.20 (b) for NSPS, a permittee certifies to the permitting authority that it is operating its collection system in*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 114 of 147 accordance with specifications for the applicable technology. The specifications describe design and operating practices for the technologies. As long as these technol ogies are operated and maintained as required, the permittee will be deemed in compliance with the associated collection rate. The only reporting requirement for this procedure would be for the permitted facilities to certify to the permit authority that it is operating according to the specifications. Since it is not practical for EPA to provi de operating specificati ons for all potential collection technologies, the pro cedure at §449.20 (a)(2) and (b)(2) allows an airport with an individual permit to propose performing ADF collection with a technology other than those described in the regulations. The permit aut hority may allow, on a case-by-case basis, an alternative ADF collection technology as the ma nner in which the permittee must demonstrate compliance with its collection requirement. The Director may also allow alternate operating parameters for one of the technologies lis ted elsewhere in § 449.20, as requested and demonstrated by the permittee. For example, an airport may operate a plug and pump system and demonstrate that it collects 40 percent of available ADF, without necessarily having all flights deiced in the designated collection area(s). Another exam ple would be an airport that utilizes a technology other than pl ug and pump, with clearly detailed technical specifications and data demonstrating it would collect 40 percent of the available ADF. A third example would be an airport that is unable or unwilling to utilize a standard se t of collection technologies and operating procedures, and instea d elects to demonstrate compliance with the ADF collection requirement by regular monitoring of applied and collected ADF. EPA has not published a specific monitoring methodology for a permittee to demonstrate its compliance with the collection requirement, but expects that such a demonstration would invol ve some type of massbalance analysis. This procedure would be de veloped by the permittee, prior to the permitting*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 115 of 147 authority proposing the permit, so that the method would be subject to public comments prior to incorporation into the permit. As long as the permittee is able to demonstrate to the permit authority’s satisfaction that the specified t echnology is designed to achieve the collection requirement as set forth in § 449.10(a)(1) or § 449.11(a)(1), the only repo rting requirement for this provision is for the permittee to certify th at it is operating and maintaining its permitted technology as required in its permit. Several pollution prevention (P2) approaches and technolog ies are described above in Section V.D.3. Although EPA did not identify any of these technologies as a basis for BAT or NSPS, these technologies may be effective at reducing available ADF. Permittees using a P2 technology for aircraft deicing may request a credit to be applied to the ADF collection requirement. Under § 449.20 (a)(2)(ii) and § 449.20 (b)(2)(ii), a permittee may request a credit by providing documentation on volumes of available ADF that would be generated in absence of the pollution prevention approach and the volumes of available ADF reduced through the use of P2. Once the permit authority determines that the reductions values are demonstrated, it will adjust the ADF collection requirement by subtrac ting the P2 available ADF reductions from the original ADF collection requirement. For exampl e, an existing airport calculated to have 1,000,000 gallons of available ADF would ordinarilybe required to demonstrate 40 percent collection (or 400,000 gallons). If the permittee can demonstrate that its P2 activities reduce the amount of available ADF to 800,000 gallons, then it would only be required to demonstrate collection of 200,000 additional gallons. Permittees may request use of alterna tive procedures at the time of permit application/renewal or throughout the permit term . A request submitted during the permit term*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 116 of 147 would be a proposed permit modification, subject to the requirements at 40 CFR 122.62 and 40 CFR part 124. D. Permit Application Requirements In order for the permit authority to determine whether an existing discharger is subject to the ADF collection and associated discharge re quirements in today’s final rule, the permittee must report its prior ADF usage when applying for permit renewal or submitting an NOI under a general permit. The permittee may also simply report that it met or exceeded the annual threshold of 60,000 gallons of normalized ADF usage. See § 122.21(s)(1). E. COD Effluent Monitori ng for Direct Dischargers Direct dischargers are required by the final rule to sample and an alyze the discharges from their treatment system for COD prior to any dilution or co-m ingling with other non-deicing waters. The sampling frequency, analytical method and reporting procedures are determined by the permit authority. Permittees must follow the sampling protocol specified in Appendix A of
Part 449. F. Alternative Compliance Option for Pavement Deicers Containing Urea While EPA expects that most airports will choose product substitution to meet the pavement deicer requirement in § 449.10(b) or § 449.11(b), airports ma y continue to use pavement deicers containing urea if they meet the alternative effluent limitation. An airport that chooses this alternative is requi red to perform an analysis for ammonia in airfield pavement discharges at all locations where pavement deic ing with deicers contai ning urea is occurring and must achieve the numeric limitations for ammoni a prior to any dilution or commingling with other non-deicing discharges. The sampling frequency, analytical method and reporting procedures are determined by the permit authority.*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 117 of 147 G. Best Management Practices Sections 304(e), 308(a), 402(a) , and 501(a) of the CWA auth orize the Administrator to prescribe BMPs as part of effluent guidelines an d standards or as part of a permit. EPA's BMP regulations are found at 40 CFR 122.44(k). Section 304(e) of the CWA authorizes EPA to include BMPs in effluent limitation guidelines for certain toxic or hazardous pollutants to control "plant site runoff, spillage or leaks, sludge or waste disposal, and drainage from raw material storage." CWA sec. 402(a)(1) and NPDES regulations (40 CFR 122.44(k)) also provide for best management practices to control or abate the discharge of pollutants when numeric limitations and standards are infeasible. In addition, CWA s ec. 402(a)(2), read in concert with CWA sec. 501(a), authorizes EPA to prescribe as wide a range of permit conditions as the Administrator deems appropriate in order to ensure complian ce with applicable effluent limitations and standards and such other requirements as the Administrator deems appropriate. There are no BMPs specified in today’s fina l rule. However, existing NPDES permits for airports include BMP requirements, and some pe rmits may have included, as required BMPs, the technologies that EPA has identifi ed as a basis for BAT or NSPS in today’s rule. Other BMPs included in airport permits include dikes, curbs, and other co ntrol measures to contain leaks and spills as part of good "housekeeping" practices. Ona facility-by-facilitybasis a permit writer may choose to incorporate BMPs into the permit. See the TDD for a detailed discussion of pollution prevention and best management pr actices used by airports and airlines. H. Upset and Bypass Provisions A “bypass” is an intentional diversion of the streams from any portion of a treatment facility. An “upset” is an exceptional incident in which there is unint entional and temporary noncompliance with technology-based permit efflue nt limitations because of factors beyond the*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 118 of 147 reasonable control of the permittee. EPA's regula tions concerning bypasses and upsets for direct dischargers are set forth at 40 CFR 122.41(m) and (n). I. Variances and Modifications The CWA requires application of effluent lim itations established pursuant to sec. 301 to all direct dischargers. However, the statute provides for the modification of these national requirements in a limited number of circumstan ces. Moreover, the Agency has established administrative mechanisms to provide an opportu nity for relief from the application of the national effluent limitation guidelines for categorie s of existing sources fo r toxic, conventional, and nonconventional pollutants. 1. Fundamentally Different Factors Variance EPA, with the concurrence of the State, may develop effluent limitations or standards different from the otherwise applicable requirements if an individual discharger is fundamentally different with respect to factor s considered in establishing the limitation of standards applicable to the individual discharger. Such a modificatio n is known as a "fundamentally different factors" (FDF) variance. EPA, in its initial implementa tion of the effluent guidelines program, provided for the FDF modifications in regulations. Th ese were variances from the BCT effluent limitations, BAT limitations for toxic and nonco nventional pollutants and BPT limitations for conventional pollutants for direct dischargers. FDF variances for toxic pollutants were challenged judicially and ultimately sustained by the Supreme Court. (Chemical Manufacturers Association v. Natural Resources Defense Council , 479 U.S. 116 (1985)). Subsequently, in the Water Quality Ac t of 1987, Congress added new CWA section 301(n). This provision explicitly authorizes m odifications of the othe rwise applicable BAT effluent limitations, if a discharger is fundamentally different with respect to the factors specified*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 119 of 147 in CWA section 304 (other than costs) from thos e considered by EPA in establishing the effluent limitations. CWA section 301(n) also defined the conditions under which EPA may establish alternative requirements. Under sec. 301(n), an application for approval of a FDF variance must be based solely on (1) information submitted during rulemaking raising the factors that are fundamentally different or (2) information the applicant did not have an opportunity to submit. The alternate limitation must be no less stringent than justified by the di fference and must not result in markedly more adverse non-water qu ality environmental impacts than the national limitation. EPA regulations at 40 CFR part 125, subpart D, authorizing the Re gional Administrators to establish alternative limitations, further detail the substantive criteria used to evaluate FDF variance requests for direct di schargers. Thus, 40 CFR 125.31(d) identifies six factors (e.g., volume of process wastewater, age and size of a discharger 's facility) that may be considered in determining if a discharger is fundamentally different. The Agency must determine whether, based on one or more of these factors, the discha rger in question is fundamentally different from the dischargers and factors considered by EPA indeveloping the nationallyapplicable effluent guidelines. The regulation also li sts four other factors (e.g., inabil ity to install e quipment within the time allowed or a discharger's ability to pay) that may not provide a basis for an FDF variance. In addition, under 40 CFR 125.31(b) (3), a request for limitations less stringent than the national limitation may be approved only if compliance with the national limitations would result in either (a) a removal co st wholly out of proportion to th e removal cost considered during development of the national limitations, or (b) a non-water quality environmental impact (including energy requirements) fundamentally mo re adverse than the impact considered during development of the national limits. The legi slative history of sec. 301(n) underscores the*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 120 of 147 necessity for the FDF variance applicant to es tablish eligibility for the variance. EPA's regulations at 40 CFR 125.32(b)(1) ar e explicit in imposing this bur den upon the applicant. The applicant must show that the factors relating to the discharge controlled by the applicant's permit which are claimed to be fundamentally different ar e, in fact, fundamentally different from those factors considered by EPA in establishing the app licable guidelines. In practice, very few FDF variances have been granted for past ELGs. An FDF variance is not available to a new source subject to NSPS. 2. Economic Variances Section 301(c) of the CWA authorizes a variance from the otherwise applicable BAT effluent guidelines for nonconventional pollutants due to economic factors. The request for a variance from effluent limitations developed fr om BAT guidelines must normally be filed by the discharger during the public notice period for the draft permit. Other filing periods may apply, as specified in 40 CFR 122.21(m)(2). Specific guidan ce for this type of variance is provided in “Draft Guidance for Application and Review of Section 301(c) Variance Requests,” August 21, 1984, available on EPA’s website at http://www.epa.gov/npdes/pubs/OWM0469.pdf

. 3. Water Quality Variances Section 301(g) of the CWA authorizes a variance from BAT effl uent guidelines for certain nonconventional pollutants due to localize d environmental factors. These pollutants include ammonia, chlorine, co lor, iron, and total phenols. J. Information Resources The Transportation Research Board (TRB), a division of the National Academies of Science, established a research panel to develop factsheets on deicing practic es to assist airports in reducing their deicing chemical usage and di scharges. A report was prepared in 2009 under*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 121 of 147 TRB’s Airport Cooperative Research Program (ACRP), titled “Deicing Planning Guidelines and Practices for Stormwater Management Systems. ” This report (DCN AD01191) and the fact sheets (DCN AD01192) are available in the docket for today’s rule.

XII. Statutory and Executive Order Reviews A. Executive Order 12866: Regulatory Planni ng and Review and Executive Order 13563: Improving Regulation a nd Regulatory Review EPA submitted this action to the Office of Management and Budget (OMB) for review under EO 12866 (58 FR 51735, October 4, 1993) and EO 13563 (76 FR 3821, January 21, 2011) and any changes made in response to OMB r ecommendations have been documented in the docket for this action. B. Paperwork Reduction Act The information collection requirements in this rule [* Insert “have been” or “will be”] submitted for approval to the Office of Manage ment and Budget (OMB) under the Paperwork Reduction Act, 44 U.S.C. 3501 et seq. The information collection requirements are not enforceable until OMB approves them. Some of the reporting requirements in today’ s rule are once per permit cycle or once per year, while others are continuous. Based on the reporting requirements in today’s rule, EPA is assessing the costs for permittees to:

 report the amount of normalized ADF usage per year, once a permit cycle.

 Annually certify non-use of airfield pavement deicer s containing urea. EPA estimates that the once-per-year cost is negligible.

 demonstrate compliance with BAT or NSPS requirements by:*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 122 of 147 o conducting and documenting annual insp ections of the ADF collection system to demonstrate compliance withtechnical specifications set forth in today’s regulation,

o analyzing COD concentrati ons of effluent, and

o conducting an assessment of their AD F collection percentage once per permit cycle. While this is not a requirement of the regulation, EPA anticipates that many permittees will opt to comply using alternate technologies or technologi es with alternate tech nical specifications, and will likely need to assess the ADF collection rate at their airport in order to determine how much additional colle ction is required. As such, EPA is likely over estimating the costs associ ated with reporting requirements by assuming all airports will conduct such an assessment. EPA estimates it would take an annu al average of 15,231 hours and $533,078 for permittees to collect and report the information required by the rule. This estimate is based on average labor rates obtained from EPA’s airport questionnaire EPA estimates it would take an average of 218 hours and $7,195 for permit authorities to review the information submitted in response to requirements in the rule as part of permit applications, renewals, and NOIs. EPA estimates that there would be no st art-up or capital cost associated with the information described above. Burden is defined at 5 CFR 1320(b). 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 EPA's regulations in 40 CFR are listed in 40 CFR part 9. In addition, EPA is amending the table in 40 CFR part 9 of curre ntly approved OMB control numbers for various*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 123 of 147 regulations to list the regulatory citations for th e information requirements contained in this final rule. C. Regulatory Flexibility Act The Regulatory Flexibility Act (RFA) gene rally requires an agency to prepare a regulatory flexibility analysis of any rule subject to notice and comment rulemaking requirements under the Administrative Procedure Act or any other statute unless the agency certifies that the rule will not have a signifi cant economic impact on a substantial number of small entities. Small entities include sma ll businesses, small organizations, and small governmental jurisdictions. For the purposes of assessing the impacts of today’s final rule on small entities, EPA determined that all airports expected to be subject to BAT requirements are owned by government entities. The RFA defines a sma ll government entity as governments of cities, counties, towns, townships, villages, school distri cts, or special district s, with a population of less than 50,000 (5 U.S.C. 601 (5)). After consider ing the economic impact of today’s final rule on small entities, including consideration of alterna tive regulatory approaches, I certify that this action will not have significant economic impact on a substantial number of small entities. After matching each airport-owning governmental entity w ith its population, EPA estimates that 20 of 198 airports subject to BAT, or 10 percent, are owned by small government entities. EPA projected impacts on these small airports using th e revenue test described in Section VIII.C.2.a. EPA found that 1 of the 20 small BAT airports are expected to incur annualized compliance costs exceeding 3 pe rcent of airport op erating revenues. In general, airlines are not directly subject to the final rule. In a small number of cases, airlines are co-permittees on NPDES permits at certain airports, and such co-permittee airlines*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 124 of 147 are therefore subject to the final rule. EPA dete rmined that 18 airlines considered small by SBA standards are co-permittees, but based on the anal ytic approach described in Section VIII.C.3, none are expected to be signi ficantly impacted by the rule Although this final rule will not have a si gnificant economic impact on a substantial number of small entities, EPA undertook a number of steps to minimize the impact of this rule on small entities. According to the FAA National Plan of Integrated Airport Systems (2007– 2011), there are almost 3,000 public us e general aviation and reliever airports in the U.S., some of which have substantial cargo service. Many, if not most, of these airports are likely to be owned by small government entities. Also likely to be owned by small governmental entities are approximately 135 non-primary commercial service airports. EPA has c hosen not to regulate any general aviation, reliever, or non-primary commercial servi ce airports under today’s final rule. EPA also estimates that in addition to the 20 small government-owned primary commercial airports, another 52 primary commercial airports are owned by small government entities, but will be out-of-scope of the regulation because little or no ADF is used at those airports. D. Unfunded Mandates Reform Act This rule does not contain a Federal mandate that may result in expenditures of $100 million or more for State, local, and tribal government s, in the aggregate, or the private sector in any one year. As explained in Section VIII a nd the TDD, the annual cost of the rule is $78 million. Thus, this rule is not subject to th e requirements of sections 202 or 205 of UMRA. By statute, a small government jurisdiction is defined as a government with a population less than 50,000 (5 U.S.C. sec. 601). Because all in-scope airports are owned by a government or governmental agency, the definition for a sma ll airport is identical for the purposes of both UMRA and SBREFA. If the rule exceeds annual compliance costs of $100 million in aggregate*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 125 of 147 all provisions of UMRA will need to be met. If the rule does not exceed $100 million in aggregate costs, but small airports are significantly or uniquely affected by the rule, EPA will be required to develop the small government agencyplan required under section 203 of UMRA because these airports are owned by small governments. This rule is also not subject to the re quirements of section 203 of UMRA because it contains no regulatory require ments that might significantly or uniquely affect small governments. The scope of the rule focuses on the airports that are the la rgest users of ADF. The rule is not projected to exceed $100 million in aggregate annual compliance costs. Further, as discussed in Section XII.C above, EPA has determined the rule will not have significant economic impact on a substantia l number of small entities. E. Executive Order 13132: Federalism This action does not have federalism implica tions. It will not have substantial direct effects on the States, on the relationship between the national government and the States, or on the distribution of power and responsibilities among the various levels of government, as specified in Executive Order 13132 (64 FR 43255, August 10, 1999). Today’s final rule requires airports to implement water po llution control requirem ents through a long-est ablished regulatory mechanism, i.e. NPDES, which is jointly admini stered by EPA and states. EPA expects the rule will have little effect on the relationship between, or the distribution of power and responsibilities among, the federal and state gov ernments. Thus, Executive Order 13132 does not apply to this action. In the spirit of Executive Order 13132 and consistent with EPA policy to promote communications between EPA and St ate and local governments, EPA specifically solicited comment on the proposed action from St ate and local officials, however none were received on the topic of federalism.*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 126 of 147 F. Executive Order 13175: Consultation and Coor dination with Indian Tribal Governments This rule does not have tribal implicati ons, as specified in Executive Order 13175 (65 FR 67249, November 6, 2000). It will not have substant ial direct effects on Tribal governments, on the relationship between the Federal government and Indian Tribes, or on the distribution of power and responsibilities between the Federal g overnment and Indian tribes. Today's rule contains no Federal mandates for Tribal gove rnments and does not impose any enforceable duties on Tribal governments. Thus, Executive Orde r 13175 does not apply to this rule. In the spirit of Executive Order 13175 and consistent with EPA policy to promote communications between EPA and Tribal governments, EPA specifi cally solicited comment on the proposed rule on tribal impacts. No comments were received on this topic. G. Executive Order 13045: Protection of Children from Environmental Health and Safety Risks EPA interprets EO 13045 (62 FR 19885, April 2 3, 1997) as applying to those regulatory actions that concern health or sa fety risks, such that the analys is required unde r section 5-501 of the Order has the potential to infl uence the regulation. This action is not subject to EO 13045 because it is based solely on technology performance. H. Executive Order 13211: Energy Effects This rule is not a "significant energyaction" as defined in Executive Order 13211, "Actions Concerning Regulations That Significantly Affect Ener gy Supply, Distribution, or Use" (66 FR 28355, May 22, 2001) because it is not likely to have a significant adverse effect on the supply, distribution, or use of ener gy, as described in Section X.A. of today’s final rule. EPA determined that the additional fuel usage would be insignificant, relative to the total fuel consumption by airports and airlines, and the total annual U.S. fuel consumption.*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 127 of 147 I. National Technology Transfer Advancement Act Section 12(d) of the Nati onal Technology Transfer and Advancement Act (NTTAA) of 1995, (P.L. 104-113, sec. 12(d); 15 U.S.C. 272 note) directs EPA to use voluntary consensus standards in its regulatory activities unless to do so would be inconsistent with applicable law or otherwise impractical. Voluntary consensus st andards are technical st andards (e.g., materials specifications, test methods, sampling procedures , and business practices) that are developed or adopted by voluntary consensus standard bodies. The NTTAA directs EPA to provide Congress, through OMB, explanations when the Agency de cides not to use avai lable and applicable voluntary consensus standards. The rulemaking involves technical standards. Therefore, the Agency conducted a search to identify potentially applicable voluntary consensus standards. However, we identified no such standards, and none were brought to our attention in comments. Therefore, EPA decided to use the technology-based controls for aircraft and ai rfield pavement deicing di scharges described in Section VI. J. Executive Order 12898: Federal Actions to Address Environmental Justice in Minority Populations and Low-Income Populations Executive Order 12898 (59 FR 7629, Feb. 16, 1994) establishes federal executive policy on environmental justice. Its ma in provision directs federal agen cies, to the greatest extent practicable and permitted by law, to make environmental justice part of their mission by identifying and addressing, as appropriate, disp roportionately high and adverse human health or environmental effects of their programs, policie s, and activities on minority populations and lowincome populations in the United States.*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 128 of 147 EPA has determined that this final rule will not have disproportionately high and adverse human health or environmental effects on mi nority or low-income populations because it increases the level of environm ental protection for all affected populations without having any disproportionately high and adve rse human health or environm ental effects on any population, including any minority or low-income population. The rule will reduce the negative effects of discharges from airports to the nation’s waters, to benefit all of society, including minority communities. K. Congressional Review Act The Congressional Review Act, 5 U.S.C. 801 et seq., as added by the Small Business Regulatory Enforcement Fairness Act of 1996, genera lly provides that before a rule may take effect, the agency promulgating the rule must submit a rule report, which includes a copy of the rule, to each House of the Congress and to the Comptroller General of the United States. EPA will submit a report containing this rule and othe r required information to the U.S. Senate, the U.S. House of Representatives, and the Comptr oller General of the United States prior to publication of the rule in the Fede ral Register. A major rule cannot take effect until 60 days after it is published in the Federal Register. This action is not a “maj or rule” as defined by 5 U.S.C. 804(2). This rule will be effective [30 days after publication in the Federal Register].

Appendix A: Abbreviations and Defi nitions Used in This Document ADF—Aircraft deicing fluid (i ncludes anti-icing fluid) AFB--Anaerobic fluidized bed treatment technology
BAT



### — Best available technology econo mically achievable, as defined by sec. 301(b)(2)(A) and sec. 304(b)(2)(B) of the CWA*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 129 of 147 BOD 5 —Biochemical oxygen demand CAFR—Comprehensive a nnual financial reports COD—Chemical oxygen demand CDP—Centralized deicing pad CPT—Cost pass-through CWA—Clean Water Act DSCR—Debt service coverage ratio EA—Economic Analysis FAA—Federal Aviation Administration
GARB



### — General airport revenue bonds GCV—Glycol collection vehicle Net income—Operating profit minus interest, taxe s, depreciation, and non-operating profits and losses NOI—Notice of Intent to discharge unde r a general permit (40 CFR 122.28(b)(2)) Normalized ADF—ADF less any water added by the manufacturer or customer before ADF application. NPDES—National Pollutant Discharge Elimination System, as defined by sec. 402 of the CWA
NSPS



### — New Source Performance Standards, as defined by sec. 306 of the CWA
O&M



### — Operations and maintenance Operating profit—Revenues minus co st of providing those services POTW—Publicly owned treatment works P2—Pollution prevention Revenues—Money received for services rendered*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 130 of 147 RFA—Regulatory Flexibility Act TDD—Technical Development Document.

List of subjects in 40 CFR Part 449 Environmental protection, Airport deicing, Airport, Airline, Wast e treatment and disposal, Water pollution control.

Dated:

____________________________ Lisa P. Jackson, Administrator.*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 131 of 147  40 CFR part 122 is amended as follows: PART 122—EPA ADMINISTERED PE RMIT PROGRAMS: THE NATIONAL POLLUTANT DISCHARGE ELIMINATION SYSTEM Subpart B—Permit Application and Sp ecial NPDES Program Requirements
Sec. 122.21 Application for a permit (applicab le to State programs, see Sec. 123.25). Authority: The Clean Water Ac t, 33 U.S.C. 1251 et seq. Add new paragraph (s) to § 122.21 to read as follows: (s) Application requirements for airport de icing permittees subject to 40 CFR part 449. In addition to the other applicati on requirements of this section: (1) Reporting Normalized Aircraft Deicing Fluid Usage. (i) The following reporting requirement appl ies to permit applications submitted on or before [insert date that is fi ve years after date of publicati on in Federal Register]: When submitting a permit renewal application or NOI, if an existing point source with at least 1,000 annual non-propeller aircraft departures has coll ected data on the annual volume of normalized aircraft deicing fluid (ADF) it has used in the pa st, it must report all such data it has collected, not to exceed data for the previous five (5) deic ing seasons. The existing point source must also report the average of the annual normalized ADF used during the ye ars for which it reports data. (ii) The following reporting requirement applies to permit applications submitted after [insert date that is five years after date of publication in Fede ral Register]: When submitting a permit renewal application or NOI, an exis ting point source with at least 1,000 annual nonpropeller aircraft departures must report all data that the existing permit has required it to collect on the annual volume of normalized ADF it has used during the term of the existing permit and the average annual volume of normalized ADF it has used during this period.*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 132 of 147 (iii) Alternatively, in lieu of subm itting actual normalized ADF usage data under subsections (i) or (ii), an ex isting point source may report that it expects to use an average volume of normalized ADF of 60,000 ga llons or more per deicing season. (2) Selection of a procedure for demonstrating compliance . The following requirements apply in the case of permits th at are subject to ADF collectio n requirements in 40 CFR 449.10 or
40 CFR 449.11: (i) Individual permits . An application for an indi vidual permit must include the applicant’s selection of a procedure to demons trate compliance with applicable ADF collection requirements as specified in § 449.20(a) for exis ting sources and § 449.20(b) for new sources. (ii) General permits . An existing source seeking cove rage under a general permit must include in its Notice of Intent its selection of a procedure to demonstrate compliance with applicable ADF collection requirements as sp ecified in § 449.20(a). A new source seeking coverage under a general permit need not includ e in its Notice of Inte nt its selection of a procedure to demonstrate compliance with ADF collection requirements – see § 449.20(b) (general permits must require use of the procedure specified inthat provision).

 40 CFR part 449 is added as follows: PART 449

—AIRPORT DEICING POINT SOURCE CATEGORY Subpart A–Airport Deicing Category
Sec. 449.1 Applicability. 449.2 General definitions.*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 133 of 147 449.10 Effluent limitations reflecting the best available technology economically achievable (BAT). 449.11 New source performance standards (NSPS). 449.20 Monitoring, reporting and recordkeeping requirements Appendix A to 40 CFR Part 449—Samp ling Protocol for Soluble COD Authority: 33 U.S.C. 1311, 1314, 1316, 1318, 1342, 1361 and 1370.

Subpart A

—Airport Deicing Category § 449.1 Applicability. (a) This part applies to discharges of pollutants from deicing operations at Primary Airports. (b) Applicability date. The requirements of §449.10(a) apply on or after [insert date that is 3 years after the date of publication in the Fe deral Register]. All other requirements of this part apply on or after [insert date that is 30 days after the date of publication in the Federal Register]. § 449.2 General definitions. The following definitions apply to this part: Advisory circular means a guidance document issued by FAA on methods, procedures or facility design. Aircraft deicing fluid (ADF) means a fluid (other than hot water) applied to aircraft to remove or prevent any accumulation of snow or ice on the aircraft. This includes deicing and anti-icing fluids. Airfield pavementmeans all paved surfaces on the airside of an airport.*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 134 of 147 Airside means the part of an airport directly involved in the arri val and departure of aircraft, including runways, ta xiways, aprons and ramps. Annual non-propeller aircraft departures means the average number of commercial turbine-engine aircraft that are pr opelled by jet, i.e. turbojet or turbofan, that take off from an airport on an annual basis, as tabulate d by the Federal Aviation Administration. Available ADF means 75 percent of the normalized T ype I aircraft deicing fluid and 10 percent of the normalized Type IV aircraft deic ing fluid, excluding aircraft deicing fluids used for defrosting or deicing for safe taxiing. Centralized deicing padmeans a facility on an airfield designed for aircraft deicing operations, constructed with a drainage system separate from the air port main storm drain system. Certification statement means a written submission to th e Director that is signed by the responsible party as defined in 40 CFR 122.22(a). Collection requirement means the requirement in §§ 449.10 and 449.11 for the permittee to collect available ADF.
COD means Chemical Oxygen Demand. Defrosting means the removal of frost contamination from an aircraft when there has been no activ e precipitation. Deicing mean procedures and practices to re move or prevent any accumulation of snow or ice on: 1) an aircraft; or 2) airfield pavement.*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 135 of 147 Deicing for safe taxiing means the application of ADF necessary to remove snow or ice to prevent damage to a taxiing aircraft.
FAA means Federal Aviation Administration. Heating degree daymeans the number of degrees per da y the daily average temperature is below 65 degrees Fahrenheit. The daily average temperature is the mean of the maximum and minimum temperature for a 24-hour period. The annual heating degree day value is derived by summing the daily heating degree days over a calendar year period. Notice of Intent (NOI) means a Notice of Intent to di scharge under a general permit, as described at 40 CFR 122.28(b)(2). Normalized aircraft deicing fluid means ADF less any water added by the manufacturer or customer before ADF application. Plug and pump collection system means a system of devices and equipment that alter an airport’s existing storm drain syst em to contain and collect ADF-contaminated stormwater. This includes, but is not limited to, temporary blocking devices at storm drain inlets, glycol collection vehicles, and/or installation of shuto ff valves in the storm sewer system. Primary Airport means an airport defined at 49 U.S.C. 47102 (15).

§ 449.10 Effluent limitations representing the best available technology economically achievable (BAT). Except as provided in 40 CFR 125.30 through 125.32, any existing poin t source with at least 1,000 annual non-propeller aircraft departures must comply with the following requirements representing the degree of effluent reduction attainable by the application of the best available technology ec onomically achievable (BAT):*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 136 of 147 (a) Where average annual normalized ADF usage, as reported pursuant to 40 CFR 122.21(s)(1), is 60,000 gallons or greater: (1) Collection requirement . The existing point source must collect at least 40 percent of available ADF; and (2) Numerical effluent limitation . The existing point source must achieve the numeric effluent limitations in Table I for available ADF collected pursuant to paragraph (1) of this subsection. The limitation must be met at the lo cation where the effluent leaves the on-site treatment system utilized for meeting these re quirements and before commingling with any nondeicing discharge.

Table I BAT Limitations

Wastestream Pollutant Daily Maximum Weekly Average
Aircraft Deicing COD 271 mg/L 154 mg/L

(b) Airfield pavement deicing discharges . There shall be no discharge of airfield pavement deicers containing urea. To comply with this limitation, any existing point source must certify annually that it do es not use airfield deicing pr oducts that contain urea or alternatively, airfield pavement discharges at any discharge point mu st achieve the numeric limitations for ammonia in Table II, prior to any dilution or commingli ng with any non-deicing discharge.*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 137 of 147 Table II BAT Limitations

Wastestream Pollutant Daily Maximum

Airfield Pavement Deicin g Ammonia as Nitro g e n 14.7 mg/L

§ 449.11 New source performance standards (NSPS). New sources with at least 1,000 annual non-prop eller aircraft departur es must achieve the following new source performance standards: (a) All new sources located in an area w ith more than 3,000 annual heating degree days must comply with the following requirements: (1) Collection requirement . The new source must collect at least 60 percen t of available ADF; and (2) Numerical effluent limitation . The new source must achieve the performance standards in Table III for available ADF collectedpursuant to paragraph (1 ) of this subsection. The limitation must be met at the location where th e effluent leaves the on-site treatment system utilized for meeting these requirements and befo re commingling with any non-deicing discharge.*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 138 of 147 Table III

NSPS

Wastestream Pollutant Daily Maximum Weekly Average
Aircraft Deicing COD 271 mg/L 154 mg/L

(b) Airfield pavement deicing discharges . There shall be no discharge of airfield pavement deicers containing urea. To comply with this limitation, any new source must certify annually that it does not use airfie ld deicing products that contain urea or alternatively, airfield pavement discharges at any disc harge point must achieve the nume ric limitations for ammonia in Table IV, prior to any dilution or comming ling with any non-deicing discharge.

Table IV

NSPS

Wastestream Pollutant Daily Maximum

Airfield Pavement Deicin g Ammonia as Nitro g e n 14.7 mg/L

§ 449.20 Monitoring, reporting and recordkeeping requirements. (a) Demonstrating compliance with the ADF collection requirement for existing point sources subject to BAT collection requirements in § 449.10 . Except as provided in 40 CFR 125.30 through 125.32, an existing point source that is an individual perm ittee shall select a*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 139 of 147 procedure under either s ubsections (1) or (2) below in its pe rmit application as the procedure for the permittee to demonstrate compliance with the applicable collection, reporting and recordkeeping requirements of this Part. If the permittee selects a pr ocedure under subsection (1), the Director shall specify in the permit th e procedure chosen by the permittee. A procedure selected by the permittee under subsection (2) may be included in the permit only with the Director’s approval, as described in subsection (2). General permits must require the permittee to use one of the procedures in subsection (1) for demonstrating compliance with the applicable collection, reporting and recordkeep ing requirements of this Part and may not allow the use of procedures in subsection (2). In its Notice of Intent, a prospective general permittee must select which of the procedures under subsection (1) it will use: (1) The permittee shall maintain records to de monstrate, and certify annually, that it is operating and maintaining one of the following ADF collection t echnologies according to the technical specifications set forth in paragraphs (i) or (ii). For both individual and general permits, these technical specifications shall be expr essly set forth as requirements in the permit. The permittee’s demonstration and valid certification are sufficient to meet the applicable BAT collection requirement without the permittee having to determin e the numeric percentage of available ADF collected. (i) Centralized Deicing Pads . Operation of a centralized de icing pad in accordance with these technical specifications meets the requirement to collect at least 40 percent of the available
ADF. (A) Each centralized deicing pad shall be sized and sited in accordance with all applicable FAA advisory circulars.*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 140 of 147 (B) Drainage valves associated with the centr alized deicing pad shal l be activated before deicing activities commence, to collect available ADF. (C) The total volume of normalized ADF spra yed at centralized deicing pads(s) must exceed 67 percent of the total volume of normalized ADF sprayed for the airport for each deicing season, not including ADF sprayed for purposes of defrosting or deicing for safe taxiing. (D) The centralized deicing pad and associated deicing equipment shall be installed and maintained per any applicable manufacturers’ instructions, and shall be inspected, at a minimum, at the beginning of each deicing season to ensure that the pad and associated equipment are in working condition. (ii) Plug and Pump Collection System . Operation of a plug and pump collection system in accordance with these technical specifications is sufficient to demonstrate compliance with a requirement to collect at least 40 percent of the available ADF. (A) All aircraft deicing sha ll take place in a location w ith an active plug and pump system, except for defrosting and deicing for safe taxiing. (B) Prior to aircraft deicing at a location, all drain blocks associated with the deicing location, including diversion valves, catch basin inserts, etc. shall be installed or activated in accordance with manufacturer specifications. (C) All open drains serving areas in which ai rcraft deicing is occu rring, shall either be blocked or have runoff diverted to another drai nage area in order to segregate ADF-contaminated

water. (D) Pumping, vacuuming or other means of ADF transport shall occur as soon as is practicable and consistent w ith safe airport operations.*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 141 of 147 (E) All equipment used in blocking storm drains, diverting runoff, or pumping/collecting/transporting ADF -contaminated water shall be installed and maintained per any applicable manufacturer’s in structions, and shall be insp ected, at a minimum, at the beginning of each deicing season to ensure the device is in working condition. (F) Glycol collection vehicles shall be used as ancillary collection for ADF overspray, to the extent airport traffic allows. (2) Alternative technology or specifications. (i) An individual permittee may request th at the permit specify one of the following alternative procedures for demonstrating compliance with its collection requirement, instead of specifying one of the procedures in subsection (1). The perm ittee must submit all information and documentation necessary to support this reques t. The permittee may request this alternative procedure in its applicat ion for permit renewal. During the term of a permit, the permittee may also request this alternative procedure as a pe rmit modification, subject to the requirements and procedures at 40 CFR 122.62 and 40 CFR part 124. If the Director determines, in his or her discretion, that the reques ted alternative procedure will achieve the collection requirement in the permit, the Director shall approve the request: (A) the use of a different ADF collection technology from th e technologies specified in paragraph (a) (1) of this section; or (B) the use of the same ADF collection tec hnology, but with differentspecifications for operation and/or maintenance; or (C) the use of a combination of any of the above ADF collection technologies. (ii) Pollution prevention credit . A permittee may apply for, and obtain credit towards, compliance with some or all of the available ADF collection requirement, provided the permittee*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 142 of 147 can demonstrate to the Director ’s satisfaction that it employs a pollution prevention technique that reduces the amount of available ADF. The cr edit shall be equivalent to the demonstrated reduction in available ADF. (iii) The Director shall set forth techni cal specifications for proper operation and maintenance of the chosen collection technology and these technical spec ifications must be expressly included as requirements in the permit. The permittee must maintain appropriate records to demonstrate compliance with these requirements. This demonstration constitutes compliance by the permittee with the percent capture requirement without the permittee having to determine the numeric percentage of ADF th at it has collected. Before the Director may approve an alternate technology under this subsection, the permittee must demonstrate to the Director’s satisfaction that the alternate tec hnology will achieve the applicable percent capture requirement. (b) Demonstrating compliance with the ADF collection requirement for dischargers subject to NSPS collection requirements in § 449.11 . Except as provided in 40 CFR 125.30 through 125.32, an individual permitt ee shall select a procedure unde r either subsections (1) or (2) below in its permit application as the procedure for the permittee to demonstrate compliance with the applicable co llection, reporting and reco rdkeeping requirements of this Part. If the permittee selects a procedure under subsection (1), the Director sh all specify in the permit the procedure chosen by the permittee. A procedur e selected by the permittee under subsection (2) may be included in the permit only with the Director ’s approval, as described in subsection (2). General permits must require the permittee to use the procedure in subsection (1) for demonstrating compliance with the applicab le collection, reporti ng and recordkeeping requirements of this Part and may not allow the use of procedures in subsection (2):*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 143 of 147 (1) The permittee shall maintain records to demonstrate, and certify annually that it is operating and maintaining one or more centralized deicing pa ds. This technology shall be operated and maintained according to the technical specifications set forth in paragraphs (i) through (iv). For both individual and general perm its, these technical specifications shall be expressly set forth as requirements in the pe rmit. The permittee’s demonstration and valid certification are sufficient to meet the applic able NSPS collection requirement without the permittee having to determine the numeric percentage of available ADF collected. (i) Each centralized deicing pa d shall be sized and sited in accordance with all applicable FAA advisory circulars. (ii) Drainage valves associated with the centr alized deicing pad shal l be activated before deicing activities commence, to collect available ADF. (iii) The centralized deicing pa d and associated deicing equi pment shall be installed and maintained per any applicable manufacturers’ instructions, and shall be inspected, at a minimum, at the beginning of each deicing season to ensure that the pad and associated equipment are in working condition. (iv) All aircraft deicing sha ll take place on a centr alized deicing pad, with the exception of defrosting and deicin g for safe taxiing. (2) Alternative technology or specifications. (i) An individual permittee may request that the permit specify one of the following alternative procedures for demonstrating compliance with its collection requirement, instead of specifying the procedure in subsection (1). The permittee must submit all information and documentation necessary to support this request . The permittee may request this alternative procedure in its initial permit application or permit renewal application. Duri ng the term of a*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 144 of 147 permit, the permittee may also request this al ternative procedure as a permit modification, subject to the requirements and procedures at 40 CFR 122.62 and 40 CFR part 124. If the Director determines, in his or her discretion, thatthe requested alternative procedure will achieve the collection requirement in the permit, the Director shall approve the request: (A) the use of a different ADF collection technology from the cen tralized deicing pad technology specified in paragraph (d )(1)(i) of this section; or (B) the use of the same ADF collection tec hnology, but with differentspecifications for operation and/or maintenance. (ii) Pollution prevention credit. A permittee may apply for, and obtain credit towards, compliance with some or all of the available ADF collection requirement, provided the permittee can demonstrate to the Director ’s satisfaction that it employs a pollution prevention technique that reduces the available ADF. The credit shall be equivalent to the demonstrated reduction in available ADF. (iii) The Director shall set forth tech nical specifications for proper operation and maintenance of the chosen collection technology and these technical spec ifications must be expressly included as requirements in the perm it. The permittee must maintain appropriate records to demonstrate compliance with these requirements. This demonstration constitutes compliance by the permittee with the percent capture requirement without the permittee having to determine the numeric percentage of ADF th at it has collected. Before the Director may approve an alternate technology under this subsection, the permittee must demonstrate to the Director’s satisfaction that the alternate tec hnology will achieve the applicable percent capture requirement. (c) Monitoring requirements.*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 145 of 147 (1) COD limitation . Permittees subject to the ADF co llection and discharge requirements specified in § 449.10 or § 449.11 must conduct compliance monitoring to demonstrate compliance with the COD limitation. Compliance must be measured at the location where the effluent leaves the on-site treatment system utilized for meeting these requirements and before commingling with any non-deicing discharge. E ffluent samples must be collected following the protocol in Appendix A. (2) Ammonia limitation . If a permittee chooses to comply with the compliance alternative specified in §449.10(b) or §449.11( b), the permittee must conduct compliance monitoring at all locations where pavement de icing with a product that contains urea is occurring, prior to any dilution or comming ling with any non-deicing discharge. (d) Recordkeeping. (1) The permit shall provide that the permittee must maintain on site, for a period of five years from the date they are created, record s documenting compliance with 40 CFR 449.20(b) through (d). These records incl ude, but are not limited to, documentation of wastewater samples collected and analyzed, certifications, and equi pment maintenance schedules and agreements. (2) At the Director’s discretion, a requireme nt may be included in the permit for the permittee to collect, and maintain on site during th e term of the permit, up to five (5) years of data on the annual volume of ADF used.

Appendix A to 40 CFR Part 449—Samp ling Protocol for Soluble COD This sampling protocol applies only to samples collected for use in measurement of COD when demonstrating compliance with the regulations set forth in this part. Co llect a representative sample of the effluent from the airport deici ng treatment system, based on the discharge permit*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 146 of 147 requirements (e.g., a grab sample or a composite sample). Because only the COD sample is filtered, do not use in-line filters if collecting a sample with a compositing device.

Grab Samples 1. Cap the container and shake the grab sample vi gorously to mix it. Remove the plunger from a 10-mL or larger Luer-lock plastic syringe equippe d with an Acrodisc Luer -lock filter containing a 1.5-μm glass fiber filter (Whatman 934-AH, or equivalent), and fill the syringe body with sample. 2. Replace the plunger and filter th e sample into a clean 50-mL screw-cap glass, plastic, or fluoropolymer bottle. Note: If testing is being done in the field, or with a test kit product (e.g., Hach Method 8000), the filtrate may be collected in the test kit vial or container. 3. Additional 10-mL volumes of sample may be filtered and the filtrate added to the same sample bottle. This additional volume may be used to repeat sample analyses or to prepare QC samples, as needed. 4. Unless the filtered sample will be analyzed wi thin 15 minutes, preserve the filtered sample with H 2 SO 4 to pH < 2. Cap the bottle and label with the sample number. Place in a cooler on ice prior to shipping. 5. Once at the analytical laboratory, the sample must be stored at ≤ 6 oC and analyzed within 28 days of collection (see the re quirements for COD in Table II at 40 CFR part 136). 6. Analyze the sample using a method approved for COD in Table IB at 40 CFR part 136. Note: Because this procedure is specific to th is point source category, it does not appear by name in 40 CFR part 136.*** E.O. 12866 Review – Draft – Do Not Cite, Quote, or Release During Review ***

Page 147 of 147 7. Report the sample results as Soluble COD in un its of mg/L. There is no Chemical Abstracts Service (CAS) Registry Nu mber for soluble COD.

Composite Samples 1. If the sample will be analyzed in a fixed laboratory (as opposed to fiel d testing), transfer at least 50 mL of well-mixed sample from the co mpositing device into a clean 50-mL screw-cap glass, plastic, or fluoropolymer bottle. Preserve the sample with H 2 SO 4 to pH < 2. Cap the bottle and label with the sample number. Pl ace in a cooler on ice prior to shipping. 2. Once at the analytical laboratory, the sample must be stored at ≤ 6 oC and analyzed within 28 days of collection (see the re quirements for COD in Table II at 40 CFR part 136). 3. Prior to analysis, remove the sample from cold storage and allow it to warm to room temperature. Shake the sample vigorously to mix it. 4. Remove the plunger from a 10-mL or larger Luer-lock plastic syringe equipped with an Acrodisc Luer-lock filter c ontaining a 1.5-μm glass fiber filter (Whatman 934-AH, or equivalent), and fill the syringe body with sample. 5. Replace the plunger and filter the sample into a clean COD vial or other suitable container. 6. Additional 10-mL volumes of sample may be filtered and the filtrate added to separate containers, as needed, to provide samples for re peat analyses or to prepare QC samples. 7. Analyze the sample using a method approved for COD in Table 1B at 40 CFR part 136. Note: Because this procedure is specific to th is point source category, it does not appear by name in 40 CFR part 136. 8. Report the sample results as Soluble COD in un its of mg/L. There is no Chemical Abstracts Service (CAS) Registry Nu mber for soluble COD.