Document ID: EPA-HQ-OW-2004-0038-0020
Agency: epa
Document Type: Proposed Rule
Title: Effluent Limitation Guidelines and New Source Performance Standards for the Airport Deicing Category
Posted Date: 2009-08-28T04:00Z

[Federal Register: August 28, 2009 (Volume 74, Number 166)]
[Proposed Rules]               
[Page 44675-44718]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr28au09-28]                         

[[Page 44675]]

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Part V

Environmental Protection Agency

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40 CFR Part 449

Effluent Limitation Guidelines and New Source Performance Standards for 
the Airport Deicing Category; Proposed Rule

[[Page 44676]]

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 449

[EPA-HQ-OW-2004-0038 FRL-8948-2]
RIN 2040-AE69

 
Effluent Limitation Guidelines and New Source Performance 
Standards for the Airport Deicing Category

AGENCY: Environmental Protection Agency (EPA).

ACTION: Proposed rule.

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SUMMARY: EPA is proposing technology-based effluent limitation 
guidelines (ELGs) and new source performance standards (NSPS) under the 
Clean Water Act (CWA) for discharges from airport deicing operations. 
The requirements generally would apply to wastewater associated with 
the deicing of aircraft and airfield pavement at primary commercial 
airports. The ELGs would be incorporated into the NPDES permits issued 
by EPA, states or tribes. EPA expects compliance with this regulation 
to reduce the discharge of deicing-related pollutants by at least 44.6 
million pounds per year. EPA estimates the annual cost of the rule 
would be $91.3 million.

DATES: Comments must be received on or before December 28, 2009. Under 
the Paperwork Reduction Act, comments on the information collection 
provisions must be received by the Office of Management and Budget on 
or before September 28, 2009.

ADDRESSES: Submit your comments, identified by Docket No. EPA-HQ-OW-
2004-0038 by one of the following methods:
     http:www.regulations.gov: Follow the on-line instructions 
for submitting comments.
     E-mail: OW-Docket@epa.gov, Attention Docket ID No. EPA-HQ-
OW-2004-0038.
     Mail: Water Docket, U.S. Environmental Protection Agency, 
Mail Code: 4203M, 1200 Pennsylvania Ave., NW., Washington, DC 20460. 
Attention Docket ID No. EPA-HQ-OW-2004-0038. Please include a total of 
3 copies. In addition, please mail a copy of your comments on the 
information collection provisions to the Office of Information and 
Regulatory Affairs, Office of Management and Budget (OMB), Attn: Desk 
Officer for EPA, 725 17th St., NW., Washington, DC 20503.
     Hand Delivery: Water Docket, EPA Docket Center, EPA West 
Building Room 3334, 1301 Constitution Ave., NW., Washington, DC, 
Attention Docket ID No. EPA-HQ-OW-2004-0038. Such deliveries are only 
accepted during the Docket's normal hours of operation, and special 
arrangements should be made for deliveries of boxed information by 
calling 202-566-2426.
    Instructions: Direct your comments to Docket No EPA-HQ-OW-2004-
0038. EPA's policy is that all comments received will be included in 
the public docket without change and may be made available online at 
http://www.regulations.gov, including any personal information 
provided, unless the comment includes information claimed to be 
Confidential Business Information (CBI) or other information whose 
disclosure is restricted by statute. Do not submit information that you 
consider to be CBI or otherwise protected through www.regulations.gov 
or e-mail. The www.regulations.gov Web site is an ``anonymous access'' 
system, which means EPA will not know your identity or contact 
information unless you provide it in the body of your comment. If you 
send an e-mail comment directly to EPA without going through http://
www.regulations.gov your e-mail address will be automatically captured 
and included as part of the comment that is placed in the public docket 
and made available on the Internet. If you submit an electronic 
comment, EPA recommends that you include your name and other contact 
information in the body of your comment and with any disk or CD-ROM you 
submit. If EPA cannot read your comment due to technical difficulties 
and cannot contact you for clarification, EPA may not be able to 
consider your comment. Electronic files should avoid the use of special 
characters, any form of encryption, and be free of any defects or 
viruses.
    Docket: All documents in the docket are listed in the http://
www.regulations.gov index. A detailed record index, organized by 
subject, is available on EPA's Web site at http://epa.gov/guide/
airport. Although listed in the index, some information is not publicly 
available, e.g., CBI or other information whose disclosure is 
restricted by statute. Certain other material, such as copyrighted 
material, will be publicly available only in hard copy. Publicly 
available docket materials are available either electronically in 
http://www.regulations.gov or in hard copy at the Water Docket in the 
EPA Docket Center, EPA/DC, EPA West, Room 3334, 1301 Constitution Ave., 
NW., Washington, DC. The Public Reading Room is open from 8:30 a.m. to 
4:30 p.m., Monday through Friday, excluding legal holidays. The 
telephone number for the Public Reading Room is 202-566-1744, and the 
telephone number for the Water Docket is 202-566-2426.

FOR FURTHER INFORMATION CONTACT: Eric Strassler, Engineering and 
Analysis Division, telephone: 202-566-1026; e-mail: 
strassler.eric@epa.gov or Brian D'Amico, Engineering and Analysis 
Division, telephone: 202-566-1069; e-mail: damico.brian@epa.gov.

SUPPLEMENTARY INFORMATION: 

Regulated Entities

    Entities potentially regulated by this action include:

------------------------------------------------------------------------
                                                          North American
                                   Example of regulated      Industry
            Category                      entity          Classification
                                                            System Code
------------------------------------------------------------------------
Industry.......................  Primary airports with         481, 4881
                                  over 1,000 annual jet
                                  departures that
                                  conduct deicing
                                  operations.
------------------------------------------------------------------------

    This section is not intended to be exhaustive, but rather provides 
a guide for readers regarding entities likely to be regulated by this 
action. Other types 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 Sec.  449.01 and the definitions in 
Sec.  449.02 of the rule and detailed further in Section IV of this 
preamble. If you still have questions regarding the applicability of 
this action to a particular entity, consult one of the persons listed 
for technical information in the preceding FOR FURTHER INFORMATION 
CONTACT section.

[[Page 44677]]

How To Submit Comments

    The public may submit comments in written or electronic form. (See 
the ADDRESSES section above.) Electronic comments must be identified by 
the docket no. EPA-HQ-OW-2004-0038 and must be submitted as a 
WordPerfect, MS Word or ASCII text file, avoiding the use of special 
characters and any form of encryption. EPA requests that any graphics 
included in electronic comments also be provided in hard-copy form. EPA 
also will accept comments and data on disks in the aforementioned file 
formats. Electronic comments received on this notice may be filed 
online at many Federal Depository Libraries. No confidential business 
information (CBI) should be sent by e-mail.

Supporting Documentation

    The rule proposed today is supported by a number of documents 
including:
     Technical Development Document for Proposed Effluent 
Limitation Guidelines and Standards for the Airport Deicing Category 
(TDD), Document No. EPA-821-R-09-004;
     Economic Analysis for Proposed Effluent Limitation 
Guidelines and Standards for the Airport Deicing Category (EA), 
Document No. EPA-821-R-09-005;
     Environmental Impact and Benefit Assessment for Proposed 
Effluent Limitation Guidelines and Standards for the Airport Deicing 
Category (EIB), Document No. EPA-821-R-09-003.

These documents are available in the public record for this rule and on 
EPA's Web site at http://epa.gov/guide/airport. They are available in 
hard copy from the National Service Center for Environmental 
Publications (NSCEP), U.S. EPA/NSCEP, P.O. Box 42419, Cincinnati, Ohio 
45242-2419, telephone 800-490-9198, http://epa.gov/ncepihom.

Overview

    The preamble describes the terms, acronyms, and abbreviations used 
in this notice; the background documents that support these proposed 
regulations; the legal authority of these rules; a summary of the 
proposal; background information; and the technical and economic 
methodologies used by the Agency to develop these regulations. This 
preamble also solicits comment and data on specific areas of interest.

Table of Contents

I. Legal Authority
II. Purpose and Summary of Proposed Rule
III. Background
IV. Scope/Applicability of Proposed Rule
V. Industry Profile
VI. Summary of Data Collection
VII. Technology Options, Costs, Wastewater Characteristics, and 
Pollutant Reductions
VIII. Economic Analysis for Airports
IX. Airline Impacts
X. Environmental Assessment
XI. Non-Water Quality Environmental Impacts
XII. Regulatory Implementation
XIII. Statutory and Executive Order Reviews
XIV. Solicitation of Data and Comments
XV. Guidelines for Submission of Analytical Data
Appendix A: Abbreviations and Definitions Used in This Document

I. Legal Authority

    EPA is proposing this regulation under the authorities of sections 
301, 304, 306, 308, 402 and 501 of the Clean Water Act (CWA), 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.

II. Purpose and Summary of Proposed Rule

    Section 304(m) of the CWA, added by the Water Quality Act of 1987, 
requires EPA to establish schedules for (1) reviewing and revising 
existing effluent limitation guidelines and standards (``effluent 
guidelines'') and (2) promulgating new effluent guidelines. On 
September 2, 2004, EPA published an Effluent Guidelines Plan (69 FR 
53705) that established schedules for developing new and revised 
effluent guidelines for several industry categories. One of the 
industries for which the Agency established a schedule was the Airport 
Deicing Category. Today EPA proposes to set national standards for 
control of wastewater discharges from deicing operations at airports. 
Deicing operations include removal of ice from aircraft, application of 
chemicals to prevent initial icing or further icing (anti-icing), and 
removal of (and preventing) ice from airfield pavement (runways, 
taxiways, aprons and ramps).
    Commercial airports and air carriers conduct deicing operations as 
required by the Federal Aviation Administration (FAA). Airport 
discharges from deicing operations may affect water quality, including 
reductions in dissolved oxygen, fish kills, reduced organism abundance 
and species diversity, contamination of drinking water sources (both 
surface and groundwater), creation of noxious odors and discolored 
water in residential areas and parkland, and other effects.
    The proposed effluent guidelines and standards address both the 
wastewater collection practices used by airports, and the treatment of 
those wastes. Airports within the scope of this proposed rule would be 
required to collect spent aircraft deicing fluid (ADF) and treat the 
associated wastewater. Additionally, airports performing airfield 
pavement deicing would be required to use non-urea-based deicers. The 
requirements would be implemented in CWA discharge permits.

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 ``restore and 
maintain the chemical, physical, and 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 
point 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 effluent 
limitation guidelines and standards (effluent guidelines or ELGs) for 
discharges from different categories of point sources, such as 
industrial, commercial and public sources.
    Congress recognized that regulating only those sources that 
discharge effluent directly into the nation's waters would not be 
sufficient to achieve the CWA's goals. Consequently, the CWA requires 
EPA to promulgate nationally applicable pretreatment standards that 
restrict pollutant discharges from facilities that discharge wastewater 
indirectly through sewers flowing to publicly owned treatment works 
(POTWs). See section 307(b) and (c), 33 U.S.C. 1317(b) and (c). 
National pretreatment standards are established for those pollutants in 
wastewater from indirect dischargers that may pass through, interfere 
with or are otherwise incompatible with POTW operations. Generally, 
pretreatment standards are designed to ensure that wastewaters from 
direct and indirect industrial dischargers are subject to similar 
levels of treatment. In addition, POTWs are required to implement local 
treatment limits applicable to their industrial indirect dischargers to 
satisfy any local requirements. See 40 CFR 403.5.
    Direct dischargers must comply with effluent limitations in NPDES 
permits. Indirect dischargers, who discharge through POTWs, must comply 
with pretreatment standards. Technology-based effluent limitations in 
NPDES

[[Page 44678]]

permits are derived from effluent limitation guidelines (CWA sections 
301 and 304) and new source performance standards (sec. 306) 
promulgated by EPA, or based on best professional judgment where EPA 
has not promulgated an applicable effluent guideline or new source 
performance standard. Additional limitations based on water quality 
standards (sec. 303) may also be included in the permit in certain 
circumstances. The ELGs are established by regulation for categories of 
industrial dischargers and are based on the degree of control that can 
be achieved using various levels of pollution control technology.
    EPA promulgates national effluent limitation guidelines and 
standards of performance for major industrial categories for three 
classes of pollutants: (1) Conventional 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 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 stormwater dischargers 
``associated 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, November 16, 1990), 
EPA designated air transportation facilities, including both airlines 
and airports, which have vehicle maintenance shops (including vehicle 
rehabilitation, mechanical repairs, painting, fueling, and 
lubrication), equipment cleaning 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 controlled 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 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 deicing discharges (73 FR 56572, September 
29, 2008). Many NPDES-authorized state agencies have issued general 
permits in their respective jurisdictions with requirements 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 in the published permit.
    For airports, the major requirements of the MSGP are:
     Develop a stormwater pollution prevention plan (SWPPP), 
including a drainage area site map, documentation of measures used for 
management of runoff, an evaluation of runway and aircraft deicing 
operations, and implementation of a program to control or manage 
contaminated runoff, including consideration of various listed control 
practices;
     Implement deicing source reduction measures, including 
minimizing or eliminating the use of urea and glycol-based deicing 
chemicals; minimizing contamination of stormwater runoff 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 gal. of glycol based 
deicing chemicals and/or 100 tons or more of urea annually, monitor 
discharges quarterly for the first four quarters of the permit cycle, 
for the following pollutants: biochemical oxygen demand 
(BOD5), 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 inspections at least monthly during the deicing 
season.
2. Individual Permits
    Some EPA and state NPDES-permitting authorities 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 contain specialized requirements for 
monitoring and/or best management practices. Some of these permits also 
contain numeric water quality-based effluent limitations (WQBELs). 
Information on water quality-based permitting is available on EPA's Web 
site at http://cfpub.epa.gov/npdes/generalissues/watertechnology.cfm.

C. Effluent Guidelines and Standards Program

    Effluent guidelines and new source performance 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 technologies. The legislative history of CWA 
section 304(b), which is the heart of the effluent guidelines program, 
describes the need to press toward higher levels of control through 
research and development of new processes, modifications, replacement 
of obsolete plans and processes, and other improvements in technology, 
taking into account the cost of controls. Congress also directed that 
EPA not consider water quality impacts on individual water bodies as 
the guidelines are developed. See Statement of Senator Muskie (Oct. 4, 
1972), reprinted 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 
indirect dischargers (discharges to publicly owned treatment works or 
POTWs).
1. Best Practicable Control Technology 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 
BPT, EPA looks at a number of factors. EPA first considers the cost of 
achieving effluent reductions in relation to the

[[Page 44679]]

effluent reduction benefits. The Agency also considers the age of the 
equipment and facilities, the processes employed, engineering aspects 
of the control technologies, any required process changes, non-water 
quality environmental impacts (including energy 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 establish 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 subcategory, 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 other factors specified in section 
304(b)(4)(B), the CWA requires that EPA establish BCT limitations after 
consideration of a two part ``cost-reasonableness'' test. EPA explained 
its methodology for the development of BCT limitations in July 1986 (51 
FR 24974). Section 304(a)(4) designates the following as conventional 
pollutants: biochemical oxygen demand measured over five days 
(BOD5), 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 level of stringency for controlling 
direct discharge of toxic and nonconventional pollutants. In general, 
BAT effluent limitation guidelines represent the best economically 
achievable performance of facilities in the industrial subcategory or 
category. The 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 impacts including energy requirements, and 
such other factors as the Administrator deems appropriate. The Agency 
retains considerable discretion in assigning the weight to be accorded 
these factors. An additional statutory factor considered in setting BAT 
is economic achievability. Generally, EPA determines 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 higher 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, even when these technologies 
are not common industry practice.
4. New Source Performance Standards (NSPS)
    New Source Performance Standards reflect effluent reductions that 
are achievable based on the best available demonstrated control 
technology. Owners of new facilities have the opportunity to install 
the best and most efficient production processes and wastewater 
treatment technologies. As a result, NSPS should represent the most 
stringent controls attainable through the application of the best 
available demonstrated control technology for all pollutants (that is, 
conventional, nonconventional, and priority pollutants). In 
establishing NSPS, EPA is directed to take into consideration the cost 
of achieving the effluent reduction and any non-water quality 
environmental impacts and energy requirements.
5. Pretreatment Standards for Existing Sources (PSES)
    Pretreatment standards apply to discharges of pollutants to 
publicly owned treatment works (POTW) rather than to discharges to 
waters of the United States. Pretreatment Standards for Existing 
Sources are designed to prevent the discharge of pollutants that pass 
through, interfere with, or are otherwise incompatible with the 
operation of POTWs. Categorical pretreatment standards are technology-
based and are analogous to BAT effluent limitation guidelines. The 
General Pretreatment Regulations, which set forth the framework for the 
implementation of categorical pretreatment standards, are found at 40 
CFR part 403. These regulations establish pretreatment standards that 
apply to all 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 at the same time it promulgates new source 
performance standards. Such pretreatment standards must prevent the 
discharge of any pollutant into a POTW that may interfere with, pass 
through, or may otherwise be incompatible with the POTW. EPA 
promulgates categorical pretreatment standards for existing sources 
based principally on BAT technology for existing sources. EPA 
promulgates pretreatment standards for new sources based on best 
available demonstrated technology for new sources. New indirect 
dischargers 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.

IV. Scope/Applicability of Proposed Rule

    EPA solicits comments on various issues specifically identified in 
this preamble as well as any other issues related to this rule that are 
not specifically addressed in today's notice.

A. Facilities Subject to 40 CFR Part 449

    EPA is proposing to establish effluent limitation guidelines and 
standards for primary commercial airports that conduct deicing 
operations and have more than 1,000 annual departures of scheduled 
commercial jet aircraft. Further information on the rationale for the 
proposed scope is provided in Section VII.D.1 of this preamble and in 
both the TDD and the EA.

B. Overview of Technology Requirements

    The proposed rule would require an airport subject to this Part to:
     Collect at least a specified proportion (either 20 or 60 
percent) of available ADF after it is sprayed on aircraft;
     Meet a specified numeric effluent limit for ADF wastewater 
collected and discharged on site; and
     Certify that it uses airfield pavement deicers that do not 
contain urea.

All references to ADF in today's proposed rule are for normalized ADF, 
which is ADF less any water added by the manufacturer or customer 
before ADF application.

    The technologies that serve as the basis for the proposed ELGs are 
summarized in Table IV-1 and Figure IV-1. These provisions are 
explained in Section VII of this preamble.

[[Page 44680]]

          Table IV-1--Summary of Proposed Airport Deicing Effluent Limitation Guidelines and Standards
----------------------------------------------------------------------------------------------------------------
                                                                        Technical components
                                                   -------------------------------------------------------------
    Regulatory level          Technology basis       Airports > 1,000 annual jet    Airports > 1,000 annual jet
                                                       departures and >= 10,000       departures and < 10,000
                                                          annual departures              annual departures
----------------------------------------------------------------------------------------------------------------
BAT.....................  1. 60% or 20% ADF         1. Capture 60% of available    1. Certify use of non-urea-
                           capture.                  ADF (for airports having >=    based pavement deicers or
                                                     460,000 gal. ADF usage) or     Meet effluent limit for
                                                     capture 20% (for airports <    ammonia.
                                                     460,000 gal. ADF usage).
                          2. Biological treatment.  2. Treat wastewater to meet
                                                     effluent limit for chemical
                                                     oxygen demand (COD).
                          3. Pavement deicer        3. Certify use of non-urea-
                           product substitution.     based pavement deicers or
                                                     Meet effluent limit for
                                                     ammonia.
NSPS....................  1. 60% ADF capture......  1. Capture 60% of available    1. Certify use of non-urea-
                                                     ADF.                           based pavement deicers or
                                                                                    Meet effluent limit for
                                                                                    ammonia.
                          2. Biological treatment.  2. Treat wastewater to meet
                                                     effluent limit for chemical
                                                     oxygen demand (COD).
                          3. Pavement deicer        3. Certify use of non-urea-
                           product substitution.     based pavement deicers or
                                                     Meet effluent limit for
                                                     ammonia.
----------------------------------------------------------------------------------------------------------------
Note: All references to ADF are for normalized ADF, which is ADF less any water added by the manufacturer or
  customer before ADF application.

[[Page 44681]]

[GRAPHIC] [TIFF OMITTED] TP28AU09.006

V. Industry Profile

A. Airport Population

    The Airport and Airway Improvement Act (AAIA), 49 U.S.C. Chapter 
471, defines airports by categories of airport activities, including 
Commercial Service (Primary and Non-Primary), Cargo Service, and 
Reliever. These categories are not mutually exclusive; an airport may 
be classified in more than one of these categories. Another group of 
generally smaller airports, not specifically defined by AAIA, is 
commonly known as ``general aviation'' airports. EPA estimates that 
there are approximately 500 commercial service airports.

[[Page 44682]]

    Commercial service airports are publicly owned airports that have 
at least 2,500 passenger boardings each calendar year and receive 
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 definition also includes passengers 
who continue on an aircraft in international flight that stops at an 
airport in any of the 50 States for a non-traffic purpose, such as 
refueling or aircraft maintenance 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 more 
than 10,000 passenger boardings each year. Primary airports are further 
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 calendar year ending 
before the start of the current fiscal year.

B. FAA Deicing Requirements

    The Federal Aviation Administration requires airlines to deice 
aircraft and airfield pavement to protect the safety of passenger and 
cargo operations. FAA regulations in 14 CFR Part 121 require a complete 
deicing/anti-icing program. The regulations in 14 CFR Parts 121, 125 
and 135 regulate takeoff when snow, ice, or frost is adhering to wings, 
propellers, control surfaces, engine inlets, and other critical 
surfaces of the aircraft. FAA does not require airlines to use a 
specific technology when deicing aircraft. In fact, airlines develop 
their own deicing protocols to meet the requirements of 14 CFR 125.221. 
Additionally, FAA has released Advisory Circulars (AC) which provide 
guidance for aircraft and airfield deicing, including AC 20-73A 
(Aircraft Ice Protection), AC 135-16 (Ground Deicing & Anti-icing 
Training & Checking), AC 120-58 (Pilot Guide: Large Aircraft Ground 
Deicing) and AC 150/5300-14B (Design of Aircraft Deicing Facilities). 
Advisory Circulars are available on FAA's Web site at http://
www.airweb.faa.gov.

C. Description of Deicing Operations

    A major concern for the safety of passengers is the clearing of ice 
and snow buildup on runways, taxiways, roadways, gate areas, and 
aircraft. Two basic types of deicing/anti-icing operations are 
generally performed at an airport: the deicing/anti-icing of aircraft, 
and the deicing/anti-icing of paved areas, including runways, taxiways, 
roadways, and gate areas. The most common technique for the deicing/
anti-icing of aircraft is the application of chemical deicing/anti-
icing agents. Deicing of runways, taxiways, and roadways is most 
commonly performed using mechanical means, but may also be performed 
using chemical agents. The anti-icing of paved areas is typically 
conducted with anti-icing chemicals.
1. Aircraft Deicing
    Aircraft deicing involves the removal of frost, snow, or ice from 
an aircraft. Aircraft anti-icing generally refers to the prevention of 
the accumulation of frost, snow, or ice. The responsibility for 
performing deicing/anti-icing varies between airports, but it is 
usually performed by a combination of individual airlines and support 
contractors, commonly called fixed-base operators (FBOs) or ground 
service providers. Airlines typically select procedures for deicing/
anti-icing their aircraft, which are then approved by the FAA.
a. Chemical Deicing Practices
    In the deicing/anti-icing process, aircraft are usually sprayed 
with deicing/anti-icing fluids (ADF) that contain chemical deicing 
agents; however, non-chemical methods are also performed. Deicing/anti-
icing occurs when the weather conditions are such that ice or snow 
accumulates on an aircraft. During snowstorms, freezing rain, or cold 
weather that causes frost to accumulate on aircraft surfaces including 
the wings, deicing is necessary to ensure the safe operation of 
aircraft. Studies have concluded that even a small amount of ice, if 
located on critical aircraft surfaces (e.g., leading edge of the wing), 
can cause significant decreases in lift.
    The typical deicing season runs from October through April for most 
airports in the northern U.S. In colder areas, the deicing season may 
extend over a longer period. In warmer climates, the deicing season may 
be shorter or deicing may rarely occur. However, it is important to 
note that deicing may be needed in hot, humid areas at any time. Some 
aircraft may experience frost build-up after landing at an airport in a 
hot, humid area. (The phenomenon is similar to frost forming on a cold 
glass of water exposed to hot, humid air and occurs for the same reason 
that the cold glass developed frost. Fuel chills when a plane operates 
at high altitudes where the temperature is very cold. When the plane 
lands in a hot, humid area, the cold fuel chills the fuel tank. If the 
tank is very close to the surface of the wing, it causes frost to form 
on the wing.)
    ADF works by adhering to aircraft surfaces to remove and/or prevent 
snow and ice accumulation. Non-chemical methods include the use of 
mechanical or thermal means (e.g., infrared heating) to prevent, 
remove, or melt ice and snow. Two types of deicing are performed: Wet-
weather and dry-weather deicing, depending on a number of climatic and 
operational factors. Wet-weather deicing is performed during storm 
events that include precipitation such as snow, sleet, or freezing 
rain. Dry-weather deicing is performed when changes in the ambient 
temperature cause frost or ice to form on aircraft but no precipitation 
is present. Dry-weather deicing may also be performed on some types of 
aircraft whose fuel tanks become super-cooled during high-altitude 
flight, resulting in ice formation at lower altitudes and after 
landing. Dry-weather deicing may occur at temperatures up to 55[deg] 
Fahrenheit (F), but generally requires a significantly smaller volume 
of deicing fluid than wet-weather deicing.
    During typical wet-weather conditions, 150 to 1,000 gallons of ADF 
may be used on a single commercial jet, while as little as 10 gallons 
may be used on a small corporate jet. An estimated 1,000 to 4,000 
gallons may be needed to deice a larger commercial jet during severe 
weather conditions. Aircraft anti-icing fluids are applied in much 
smaller volumes than their deicing counterparts are. A commercial jet 
requires approximately 35 gallons of fluid for anti-icing after 
deicing. Generally, dry-weather deicing requires 20 to 50 gallons of 
deicing fluid, depending on the size of the aircraft.
    Chemical aircraft deicers are categorized into four classes. Not 
all types are currently used. Fluid types vary by composition and 
allowed holdover time (the estimated time for which deicing/anti-icing 
fluid will prevent the formation of frost or ice and the accumulation 
of snow on the treated surfaces of an aircraft). Type I is the most 
commonly used fluid and is used primarily for aircraft deicing. These 
types of fluids typically contain glycol as the active ingredient 
(usually ethylene glycol or propylene glycol), along with water and 
additives, and remove accumulated ice and snow from aircraft surfaces. 
Types II, III, and IV were developed for anti-icing. These fluids form 
a protective anti-icing film on aircraft surfaces to prevent the 
accumulation of ice and snow. Anti-icing fluids are composed of either 
ethylene glycol or propylene glycol, a small amount of thickener, 
water, and additives. The additives in aircraft

[[Page 44683]]

deicing and anti-icing fluids may include corrosion inhibitors, flame 
retardants, wetting agents, identifying dyes, and foam suppressors. 
Type IV fluids can provide up to a 70 minute holdover time, depending 
on atmospheric conditions. (Holdover time is the amount of time a given 
aircraft treatment by ground anti-icing fluid remains effective. 
Holdover time effectively runs out when frozen deposits start to form 
or accumulate on treated aircraft surfaces.) Most large airlines use 
both Type I and Type IV fluids.
    Aircraft deicing and anti-icing operations usually occur at 
terminal gates, gate aprons, taxiways, or centralized deicing pads. 
Centralized deicing pads may be located near terminals and gates, along 
taxiways serving departure runways, or near the departure end of 
runways. Each airport may use only one or a combination of all of these 
locations for deicing/anti-icing. The amount and type of deicing 
performed at each location may vary. For example, an airport with 
deicing pads may allow air carriers to perform minimal deicing at 
gates, at a level sufficient to move the aircraft safely, and require 
all other deicing operations to be conducted at a pad.
    If deicing is not conducted at the gate, then, prior to takeoff, an 
aircraft will taxi to an airport-approved deicing/anti-icing location. 
Depending on the deicing location design, several aircraft may be 
deiced simultaneously on a single deicing pad. Deicing trucks and/or 
spray equipment mounted on fixed booms apply the appropriate ADF. One 
to four deicer trucks may be used for deicing a single aircraft, 
depending on its size and weather conditions. When holdover times are 
exceeded prior to takeoff, secondary deicing/anti-icing is necessary. 
If an aircraft must return to the gate or another designated location 
for secondary deicing/anti-icing, its departure may be substantially 
delayed. The need for secondary deicing will likely decrease as more 
airlines use Type IV fluids to extend the allowable holdover time.
    While the FAA has issued regulations and guidance on conducting 
deicing/anti-icing operations, the aircraft pilot is ultimately 
responsible for determining whether the deicing performed is adequate. 
The pilot may inspect the aircraft after deicing and order additional 
deicing or anti-icing.
    Dry-weather deicing, also referred to as clear ice deicing, may be 
performed whenever ambient temperatures are cold enough to form ice on 
aircraft wings (below 55[deg] F). Dry-weather deicing is also used to 
defrost windshields and wingtips on commuter planes and is usually 
conducted throughout the entire deicing/anti-icing season.
b. Non-Chemical Deicing Practices
    Non-chemical deicing methods involve mechanical or thermal means to 
remove ice and snow from aircraft surfaces. Dry, powdery snow can be 
swept from aircraft using brooms or brushes. Hot air blowers can also 
be used to remove snow mechanically with forced air and to melt ice and 
snow. In addition, some smaller aircraft are equipped with inflatable 
pneumatic or hydraulic boots that can expand to break ice off the 
leading edges of wings and elevators.
    Mechanical snow removal methods (e.g., using nylon brooms and ropes 
to remove snow from parked aircraft) are typically only used in the 
early morning because they are time-intensive and labor-intensive, and 
would be too disruptive to airline schedules during the day. Mechanical 
methods are typically also used in conjunction with fluid application 
and are dependent on climate and operational variables. Personnel must 
be properly trained and provided with appropriate equipment so as not 
to damage navigational equipment mounted on aircraft. Airlines 
typically use brooms to remove as much snow and ice as possible before 
applying conventional aircraft deicing fluids.
    Other non-chemical deicing practices--infrared heating, forced air 
and hot air systems--are being used at several airports throughout the 
U.S. These technologies are described in Section VII.B.3, Pollution 
Prevention Technologies.
2. Airfield Pavement Deicing
    Pavement snow removal and deicing/anti-icing removes or prevents 
the accumulation of frost, snow, or ice on runways, taxiways, aprons, 
gates, and ramps. A combination of mechanical methods and chemical 
deicing/anti-icing agents is used for pavement deicing at airports. 
Runway deicing/anti-icing is typically performed by airport personnel 
or a contractor hired by the authority. Some ramp, apron, gate, and 
taxiway deicing/anti-icing may be performed by other entities, such as 
airlines and FBOs that operate on those areas. Pavement deicing 
typically occurs during the same season as aircraft deicing, but may be 
shorter or longer than the aircraft deicing season.
a. Mechanical Methods
    Mechanical methods, such as plows, brushes, blowers, and shovels 
for snow removal, are the most common form of runway deicing, and may 
be used in combination with chemical methods. Airports generally own 
multiple pieces of snow removal equipment and have employees trained to 
operate them. Sand may be used to increase the friction of icy paved 
areas. Because winter storm events can be unpredictable, personnel 
trained in pavement deicing/anti-icing may be available at an airport 
24 hours a day during the winter season.
b. Chemical Methods
    Because ice, sleet, and snow may be difficult to remove by 
mechanical methods alone, most airports use a combination of mechanical 
methods and chemical deicing agents. Common pavement deicing and anti-
icing agents include potassium acetate, sodium acetate, urea, ethylene 
glycol-based fluids, propylene glycol-based fluids, and sodium formate. 
Road salt (i.e., sodium chloride or potassium chloride) may be used to 
deice/anti-ice paved areas that are not used by aircraft (e.g., 
automobile roadways and parking areas) but are not considered suitable 
for deicing/anti-icing taxiways, runways, aprons, and ramps because of 
their corrosive effects on aircraft.
    Many airports perform deicing of heavy accumulations of snow and 
ice using mechanical equipment followed by chemical applications. 
Pavement anti-icing may be performed based on predicted weather 
conditions and pavement temperature. Deicing and anti-icing solutions 
are applied using either truck-mounted spray equipment or manual 
methods.
3. Estimates of Deicing Activity
a. Aircraft Deicing Chemical Usage
    Airlines use approximately 25 million gallons of ADF annually, 
consisting of 22.1 million gallons of propylene glycol-based deicers 
and almost 3 million gallons of ethylene glycol-based deicers. EPA 
estimates that approximately 320 primary airports conduct deicing 
operations annually and that approximately 85 percent of this ADF (21.6 
million gallons) is used at 110 of the 320 airports.
b. Airfield Pavement Deicing Chemical Usage
    Primary airports use approximately 71 million pounds of chemical 
deicers on airfield pavement (runways, taxiways and ramps) annually. 
The six most frequently used deicers, with estimated percentages by 
weight, are as follows: potassium acetate (63 percent); urea (12 
percent); propylene glycol-based fluids (11 percent); sodium acetate (9 
percent);

[[Page 44684]]

sodium formate (3 percent); and ethylene glycol-based fluids (2 
percent).

VI. Summary of Data Collection

A. Previous EPA Data Collection Activities

1. 1993 Screener Questionnaire
    In 1992, EPA began developing effluent guidelines and standards for 
the Transportation Equipment Cleaning (TEC) category (40 CFR Part 442). 
The scope of the TEC regulation at that time included facilities that 
clean the interiors of tank trucks, rail tank cars, and tank barges; 
facilities that clean aircraft exteriors; and facilities that deice/
anti-ice aircraft and/or airport pavement. Initial data collection 
efforts for this project related to airport deicing operations included 
development and administration of a ``screener'' questionnaire that was 
administered in 1993. The screener questionnaire was developed, in 
part, to enable EPA to: (1) Identify facilities that perform TEC 
aircraft operations; (2) evaluate facilities based on wastewater, 
economic, and operational characteristics; and (3) develop technical 
and economic profiles of the industry. Subsequent to distribution of 
the screener questionnaire, EPA decided not to include the aircraft 
segment as part of the TEC effluent guidelines that were promulgated in 
2000 (65 FR 49665, August 14, 2000). The Agency indicated that its 
recently-issued stormwater regulations and permits under the NPDES 
program imposed new requirements for airport discharges, and that 
aircraft cleaning and airport deicing operations were significantly 
different from other portions of the TEC category.
    EPA mailed the screener questionnaire to 760 entities that 
potentially perform aircraft exterior cleaning and/or aircraft or 
pavement deicing/anti-icing operations. Following the screener 
questionnaire mail-out and analyses of responses, EPA estimated that, 
in 1993, there were 588 entities (i.e., airlines and FBOs) that perform 
deicing/anti-icing operations.
2. 1998-99 Preliminary Data Summary
    EPA conducted a study of airport deicing practices in 1998-99 and 
published a report in 2000. (Preliminary Data Summary: Airport Deicing 
Operations (Revised), Document No. 821-R-00-016, August 2000). The 
study described deicing operations in the industry, wastewater 
characteristics and procedures for its collection and treatment. The 
study was conducted to comply with CWA sec. 304(m), which requires the 
Agency to publish a biennial Effluent Guidelines Plan, and a consent 
decree in Natural Resources Defense Council and Public Citizen, Inc. v. 
Browner (D.D.C. 89-2980, as modified February 4, 1997). As part of the 
study, EPA distributed short questionnaires to several aviation 
sectors, including those involved in deicing; conducted site visits to 
airports; and conducted wastewater sampling episodes.
a. Questionnaires
    In 1999, EPA sent questionnaires to airports, an airline industry 
association, equipment vendors, and publicly owned treatment works 
(POTW), and requested data about the 1998-99 deicing season. The 
Airport Questionnaire was sent to nine airports and asked for 
information on aircraft and airfield deicing activities; wastewater 
handling and treatment; and airport structure, finances and operations. 
A questionnaire requesting financial data was sent to an airline 
industry association, which provided information about the deicing 
operations of 12 of its members, and eight regional airlines also 
received questionnaires. The Vendor Questionnaire was sent to nine 
businesses and requested information about equipment used to collect, 
control, recycle/recover, treat or reduce the generation of glycol-
contaminated wastewater from aircraft and airfield deicing operations. 
The POTW Questionnaire was sent to nine facilities and requested 
information about potential pollutants in wastewater discharges from 
airports, and the potential environmental impacts stemming from POTWs' 
acceptance of these wastes.
b. Wastewater Sampling
    EPA conducted six sampling episodes for the study. Two of these 
episodes obtained data on ADF, and four episodes obtained data on ADF-
contaminated wastewater and final effluent data from airports with 
various collection and treatment systems.
c. Airport Site Visits
    EPA visited 16 airports between 1997 and 1999 (including one visit 
before the formal commencement of the study). Information gathered 
included deicing operations, names and quantities of deicing chemical 
products used, wastewater characterization, treatment technologies and 
costs, and financial data. The Agency obtained effluent self-monitoring 
data from some of the airports that were visited.
d. Other Data Sources
    EPA collected data on NPDES permits and from the Toxic Release 
Inventory database, which have wastewater discharge information. EPA 
also collected data from state, local, and other federal agencies, 
including the FAA, Department of Transportation and the United States 
Geological Survey (USGS); and Canadian federal agencies involved with 
airport environmental issues. These included interviews conducted 
during site visits, airport effluent monitoring data, airline 
operations data (i.e., departures and enplanement statistics), and 
economic and financial information about the industry. All of the 
collected data are available in the record for this proposed rule.

B. 2006-07 Industry Surveys

    For this proposed rule, EPA developed a series of survey 
questionnaires to compile a complete profile of the industry with 
regard to type and amounts of deicing chemicals used, collection 
systems, and wastewater treatment systems. These questionnaires 
expanded on the Agency's earlier survey efforts by the design of a 
scientific national statistical sample of airports and development of a 
reasonable national estimate of deicing activity by major airlines. A 
comprehensive set of questions and data tables was also developed. In 
designing the questionnaires, EPA consulted with airport and airline 
industry representatives, including the American Association of Airport 
Executives (AAAE), Airports Council International--North America (ACI-
NA) and the Air Transport Association (ATA). The Office of Management 
and Budget (OMB) approved the questionnaires on January 13, 2006, and 
EPA distributed the questionnaires during 2006 and 2007.
1. Airline Screener
    EPA designed a short ``screener'' questionnaire to obtain basic 
information from air carriers on which organizations actually performed 
deicing services for a particular carrier, at specified airport 
locations (i.e., the airline conducted its own deicing, it contracted 
with another airline, or it used an FBO). EPA used the results of this 
questionnaire to select respondents for the Detailed Airline 
Questionnaire. The screener was distributed to 72 airlines and 
requested information on deicing activities at 149 airports. EPA 
distributed the screener to the industry in April 2006.
2. Airport Questionnaire
    EPA designed the Airport Deicing Questionnaire to serve as the 
Agency's primary data source for airport-specific

[[Page 44685]]

information. The questionnaire requested information on a number of 
topics including, general airport information, deicing operations, 
deicing stormwater collection and conveyance, deicing stormwater 
treatment, sampling data, pollution prevention, receiving waters, and 
airport financial information.
    EPA distributed the Airport Deicing Questionnaire to the industry 
in April 2006. The questionnaire was sent to 153 airports, including a 
census of all large and medium hub airports, as well as a sample survey 
of all Small and Non-Hub Airports. (General aviation airports were not 
included in the survey, except for a few with large cargo operations, 
because these airports are used mainly by small private airplanes that 
typically do not fly during icing conditions, and therefore are sites 
where little or no ADF use occurs.)
3. Detailed Airline Questionnaire
    EPA designed the Detailed Airline Questionnaire in order to learn 
more about the airlines' role in deicing operations, as well as to get 
information that is more precise on ADF usage. This questionnaire was 
EPA's primary data source for airline-specific information. The 
questionnaire asked questions on topics including deicing operations, 
ADF purchase and usage, pollution prevention practices, and operational 
costs. The questionnaire was sent in March 2007 to 58 air carriers, 
covering deicing operations at 57 airports. This questionnaire 
requested information on a number of topics including: General airline 
information, airline deicing practices, pollution prevention practices 
and deicing costs.

C. Site Visits

    In order to become familiar with the day-to-day operations at 
airports, as well as learn some of the more site-specific issues that 
arise with deicing, EPA conducted site visits at more than 20 airports. 
EPA visited airports that had specific treatment technologies in place, 
in order to learn more about these technologies. Some of the airports 
included were Denver, Pittsburgh and General Mitchell (Milwaukee). All 
site visits were documented with Site Visit Reports (SVRs), which are 
in the record for today's proposed rule (Record Index, Section 2.3).

D. Wastewater Sampling Episodes

    EPA collected several wastewater samples for chemical analysis 
during sampling episodes at six airports to characterize pollutants 
found in ADF-contaminated runoff, and to assess the performance of 
treatment systems. The Agency conducted episodes at these six airports 
in 2005 and 2006: Minneapolis/St. Paul International Airport, Detroit 
Metropolitan Wayne County International Airport, Albany International 
Airport, Denver International Airport, Greater Rockford (Illinois) 
Airport, and Pittsburgh International Airport. At the first two 
airports, EPA conducted one-day sampling episodes, to provide a general 
characterization of wastewater from deicing operations. The subsequent 
four events were multiple-day performance sampling episodes, which were 
designed to document the performance of wastewater treatment systems.
    For each analytical chemical class or parameter, EPA collected 24-
hour composite samples when possible, in order to capture the 
variability in the waste streams containing ADF generated throughout 
the day. EPA used the data from the laboratory analyses of these 
samples to develop a list of pollutants of concern, and characterize 
the raw wastewater at airports. EPA used the data collected from the 
influent, intermediate, and effluent points to analyze the efficacy of 
treatment at the facilities, and to develop current discharge 
concentrations, loadings, and the treatment technology options for the 
Airport Deicing effluent guideline. EPA used effluent data, along with 
data provided by industry in the questionnaires and other sources, to 
calculate the long-term averages and limitations for each of the 
proposed regulatory options. During each sampling episode, EPA 
collected flow rate data corresponding to each sample collected and 
production information from each associated production system for use 
in calculating pollutant loadings. EPA has included in the public 
record all information collected for which a facility has not asserted 
a claim of Confidential Business Information (CBI) or which would 
indirectly reveal information claimed to be CBI.
    After conducting the sampling episodes, EPA prepared sampling 
episode reports for each facility. These reports included descriptions 
of the wastewater treatment processes, sampling procedures, and 
analytical results. EPA documented all data collected during sampling 
episodes in the sampling episode report for each sampled site. Non-
confidential business information from these reports is available in 
the public record for this proposal. For detailed information on 
sampling and preservation procedures, analytical methods, and quality 
assurance/quality control procedures see the Quality Assurance Project 
Plans and the Sampling and Analysis Plans (Record Index, Section 2.4).

E. Other Data Collection

    EPA collected other information from various other data sources 
including: National Pollutant Discharge Elimination System (NPDES) 
permits for information on current permit requirements; industry 
correspondence on technology costs and long-term wastewater monitoring 
data; and searches of technical and scientific literature, covering 
current deicing practices and treatment technologies, current airport 
deicing runoff data, chemical information and environmental impact 
studies, and current stormwater regulations in the United States and 
other countries.

F. Summary of Public Participation

    EPA has met or corresponded with many airport and airline 
representatives, citizen and environmental groups, vendors of deicing 
chemicals and equipment, state permit agencies, other Federal agencies 
and engineering consulting firms. The Agency has attended conferences 
on airport deicing and has given presentations at several of those 
conferences. Correspondence from these organizations about the proposed 
rule is in the Record for the proposed rule.

VII. Technology Options, Costs, Wastewater Characteristics, and 
Pollutant Reductions

A. Wastewater Sources and Wastewater Characteristics

1. Aircraft Deicing
    Most ADF is applied to aircraft through pressurized spraying 
systems, mounted either on trucks that move around an aircraft, or on 
large fixed boom devices located at a pad dedicated to deicing. 
Airlines typically purchase ADF in concentrated form (normalized) and 
dilute it with water prior to spraying.
    Most of the aircraft deicing fluid is Type I fluid, which is not 
designed to adhere to aircraft surfaces. Consequently the majority of 
Type I ADF is available for discharge due to dripping, overspraying, 
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 pavements. 
(These chemicals typically include aircraft fuel, lubricants and 
solvents, and metals from aircraft, ground support and utility 
vehicles.) Water containing these substances enters an airport's storm 
drain system. At many airports, the

[[Page 44686]]

storm drains discharge directly to waters of the United States with no 
treatment.
    Type IV fluid, an anti-icing chemical, is designed to adhere to the 
aircraft. Because of this adherence characteristic, EPA estimated that 
the majority of Type IV fluid is not available for discharge.
    For the purposes of this proposed rule, the pollutant loadings are 
discussed in terms of applied ADF and how much of that is expected to 
be discharged. A more detailed discussion of loadings estimates is 
presented later in this section. Given the highly variable nature of 
storm events, it is difficult to estimate flows or concentrations of 
ADF-contaminated stormwater generated at an airport. Those factors are 
greatly dependent on the size of the storm event associated with the 
discharge, drainage characteristics, ADF collection systems (if 
present), and airport operations. Additionally, due to the design of 
drainage systems at some airports, their discharges may occur well 
after a storm event has completed.
2. Airfield Pavement Deicing
    Most solid airfield deicing chemical products are composed of an 
active deicing ingredient (e.g., potassium acetate, sodium acetate) and 
a small amount of additives (e.g., corrosion inhibitors). Liquid 
airfield 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., 
potassium acetate, sodium acetate, and sodium formate) will all ionize 
in water, creating positive salt ions (K\+\, Na\+\), BOD5 
and COD load as the acetate or formate ion degrades into carbon dioxide 
(CO2) and water. Pavement deicers containing urea will 
degrade to ammonia, and generate BOD5 and COD load as well.
    Most of EPA's sampling data does not include airfield pavement 
deicers. However, EPA collected samples from a few locations at Detroit 
Metro Airport that contain airfield deicing stormwater. Large hub 
airports, both Detroit Metro and Pittsburgh, provided sampling data 
associated with stormwater contaminated by airfield pavement deicers. 
More information on these sampling activities is provided in the TDD. 
As with the aircraft deicers, the variablity of storm events and 
drainage systems make it difficult to estimate flows or concentrations 
of pavement deicing waste streams generated at an airport.

B. Control and Treatment Technologies in the Aviation Industry

    The ADF application process has presented a challenge for airports 
attempting to manage their contaminated stormwater streams. The 
airlines' process of applying ADF to aircraft through high pressure 
spraying, combined with their typical practices 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 multiple locations. This process 
contrasts sharply with many other industries where pollutants are 
generated in confined areas, managed through a piping system, and not 
commingled with precipitation.
    EPA has identified several technologies that are available to 
collect and manage portions of the ADF wastestream. Some of these 
collection technologies are more effective than others; however, EPA 
has not identified any single technology that is capable of collecting 
all applied ADF. Typically, ADF that is not captured becomes available 
for discharge, either through an airport's drainage system, or from 
shearing off the aircraft during takeoff.
    Once the ADF wastestream is collected, it can be treated, and this 
process is similar to many other industries that generate wastewater. 
EPA identified four technologies available for treating ADF wastewater.
    EPA also examined pollution prevention technologies, which can 
reduce or eliminate use of ADF chemicals and urea for pavement deicing.
1. Aircraft Deicing Fluid Collection Technologies
a. Glycol Recovery Vehicle
    A glycol recovery vehicle (GRV) is a truck that utilizes a vacuum 
mechanism to gather stormwater contaminated with ADF resulting from 
deicing operations. A GRV is a modular technology, in that collection 
capacity can be increased by using additional units, without the 
complicating factors of in-ground construction associated with some 
other technologies. An airport may increase its overall ADF collection 
capacity by purchasing or leasing larger units and/or additional units.
    GRV trucks are typically stationed near the ADF spraying trucks and 
are deployed either during aircraft deicing activities or, after the 
aircraft deicing activity has completed. The truck then transports the 
ADF-contaminated stormwater to an on-site storage facility, after which 
the material is either treated at the airport or sent off site for 
treatment. EPA estimates that GRVs typically capture approximately 20 
percent of the available ADF when properly operated and maintained.
b. Plug and Pump
    The plug-and-pump collection system involves simple alterations to 
an airport's existing storm drain system, typically the insertion of 
blocking plugs or similar devices in storm drains, combined with use of 
GRVs, to contain and collect ADF-contaminated stormwater. Drainage 
system modifications involve the placement of temporary blocking 
devices at storm drain inlets, and/or installation of shutoff valves at 
one or more points in the storm sewer system. Before a deicing event 
begins, airport personnel activate the blocking devices, which trap the 
ADF-contaminated stormwater in the collection system. After the deicing 
activity ceases, the vacuum trucks pump the contaminated stormwater 
from the storm sewer system and transport the liquid to on-site storage 
and subsequent treatment. EPA estimates that plug-and-pump systems, 
which incorporate GRVs, may capture approximately 40 percent of the 
available ADF when properly operated and maintained.
c. Centralized Deicing Pads
    A centralized deicing pad is a facility on an airfield built 
specifically for aircraft deicing operations. It is typically a paved 
area adjacent 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 GRVs in combination with centralized deicing pads 
in order to maximize collection and containment of ADF-contaminated 
stormwater. Airports typically locate 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.
    Centralized deicing pads reduce the volume of deicing wastewater by 
restricting deicing to very small areas, and managing the captured 
wastewater through a dedicated drain system. EPA estimates that central 
deicing pads allow airports to capture about 60 percent of the 
available ADF.

[[Page 44687]]

    In addition, although the name implies a small collection area, 
central pads designed to accommodate more than one commercial aircraft 
generally encompass several acres. A deicing pad is specially graded 
and designed to capture highly contaminated runoff, which can then be 
sent to storage ponds, tanks or directly to treatment. By capturing 
high concentrations of spent ADF, the feasibility of recycling 
increases. Recovered glycol is typically sold to chemical manufacturers 
for use in a variety of products, including coatings, paints, plastics 
and polyester fibers.
d. Summary of ADF Collection Technology Usage
    EPA estimates the number of airports that use each of the above 
collection technologies in Table VII-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 VII-1--Estimated Totals of ADF Collection Technologies Used by
                                Airports
------------------------------------------------------------------------
                                                              Number of
                   Collection technology                       airports
------------------------------------------------------------------------
Glycol Recovery Vehicle....................................           53
Plug and Pump..............................................           29
Centralized Deicing Pad....................................           66
------------------------------------------------------------------------

    See the Technical Development Document for further explanation of 
EPA's estimates of the ADF capture rates for the fluid collection 
technologies.
2. Wastewater Treatment and Recycling Technologies
    EPA identified four potential BAT wastewater technologies. Two of 
these technologies are biological in that they use microorganisms to 
break down the glycol. The other two technologies are mechanical and 
produce two wastestreams, one a high concentrated glycol stream, and 
one that is primarily water for discharge. The high glycol stream can, 
in some instances, be recycled and used for a variety of products. 
There have been limited instances in the U.S. of recycled glycol used 
for ADF formulation.
a. Anaerobic Fluidized Bed
    An Anaerobic Fluidized Bed (AFB) treatment system uses a vertical, 
cylindrical tank in which the ADF-contaminated stormwater is pumped 
upwards through 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 activated carbon 
particle, providing a vast surface area for biological growth. These 
microorganisms provide treatment of the ADF-contaminated stormwater. 
Byproducts from the AFB treatment system include methane, carbon 
dioxide and new biomass (animal material, e.g. bacteria).
    Treating wastes using an anaerobic biological system as compared 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 the biological process is 
contained in a sealed reactor, odors are eliminated. Based on EPA 
sampling results, the AFB treatment system successfully removed over 98 
percent of BOD5, over 97 percent of COD, and over 99 percent 
of propylene glycol from the wastestream. This reduced the 
BOD5 and COD loads discharged to receiving waters by over 98 
and 97 percent, respectively. Two airports in the United States use the 
AFB technology: Albany County Airport in Albany, New York, and Akron-
Canton Regional Airport, Akron, Ohio.
b. Ultrafiltration/Reverse Osmosis
    Ultrafiltration/Reverse Osmosis (UF/RO) technology filters ADF-
contaminated stormwater at a high temperature (75 [deg]C) using an 
ultrafiltration membrane as its first stage. Next, the deicing fluid 
(filtrate) can be dewatered using a reverse osmosis membrane as a 
second stage. Since the ultrafiltration membrane is effective at 
removing contaminants, the RO stage is used for dewatering and glycol 
separation. This process produces a glycol-laden stream that can be 
distilled in an additional stage to increase its glycol concentration. 
Concentrated glycol streams can be recycled as a feedstock in chemical 
manufacturing. The effluent from the UF/RO system contains small 
amounts of glycol, carbonaceous BOD (cBOD) and COD, and can either be 
discharged to surface water, or sent to a POTW for further treatment.
    Based on EPA sampling results, the RO treatment system successfully 
removed over 99 percent of BOD5, over 99 percent of COD, and 
over 99 percent of propylene glycol. UF/RO technology is used at 
Pittsburgh International Airport.
c. Mechanical Vapor Recompression and Distillation
    Mechanical Vapor Recompression (MVR) followed by distillation is 
typically used when glycol concentrations in ADF-contaminated 
stormwater are greater than 5 percent. This type of a system is not 
generally practical for lower concentration glycol contaminated 
stormwater, which would typically be discharged directly to a POTW for 
treatment. The MVR/distillation technology generates a concentrated 
glycol stream (containing greater than 99 percent glycol) that can be 
sold as a chemical feedstock. The effluent from the MVR/distillation 
system contains propylene glycol, cBOD and COD and it must be 
discharged to a POTW for further treatment.
    MVR and distillation is used at Denver International Airport for 
recycle and recovery of spent ADF. The system first treats ADF-
contaminated stormwater using the MVRs, which increase the glycol 
concentration to approximately 40 percent. Effluent from the MVRs is 
then treated by distillation to increase the glycol concentration to 
approximately 99 percent. The glycol product is passed through 
polishing filters to remove residual contaminants allowing for resale 
of the product as a chemical feedstock. Overheads (distillate) from 
both the MVRs and distillation columns contain propylene glycol and 
they are sent to a POTW for additional treatment.
    Based on EPA sampling results, the MVR/Distillation treatment 
system successfully removed over 93 percent of BOD5, over 97 
percent of COD, and over 98 percent of propylene glycol.
d. Aerated Pond
    An aerated pond uses mechanical aerators either to inject air into 
the wastewater or to cause violent agitation of wastewater and air in 
order to achieve oxygen transfer to the wastewater. Bacteria are 
suspended in the wastewater, and aid in the biodegradation of glycol. 
Contaminated stormwater is retained in the detention pond during the 
deicing season and discharged later, after microorganisms present in 
the pond have biodegraded the glycols. The detention pond is monitored 
and nutrients are added, pH is adjusted, and anti-foaming agents are 
added as needed. The biodegradation of glycol is temperature-dependant 
and predominantly occurs during the spring and early summer months when 
ambient temperatures are higher. When the BOD5 concentration 
has been sufficiently reduced, the volume is discharged to surface 
waters.
    Based on EPA sampling results, the aerated pond treatment system 
successfully removed 100 percent of BOD5, and over 93 
percent of COD. An aerated pond system is currently in use

[[Page 44688]]

at Greater Rockford Airport, in Rockford, Illinois.
3. Pollution Prevention Technologies
    EPA has identified several technologies that reduce ADF usage to 
some extent while safely deicing aircraft, and one applicable to 
airfield pavement deicing, that are in use at airports across the 
United States. However, there are limited data on the actual pollutant 
reductions that these technologies may achieve. While the effectiveness 
or cost-effectiveness of these technologies has not been documented, 
these technologies can reduce the amount of deicing chemicals required 
to deicing aircraft and airfields. The reduction of chemicals will not 
only have a positive environmental effect, but may also be cost-
effective, as the decrease in costs of purchased deicing chemicals may 
offset the cost of the technology itself.
a. Infrared Deicing Systems
    A few U.S. airports have used infrared (IR) heating systems for 
several years. The systems have been demonstrated to deice aircraft 
effectively, which substantially reduces ADF usage. 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 specific 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. Although the 
system can deice an aircraft, it cannot provide aircraft with anti-
icing protection. Consequently, when the ambient temperature is below 
freezing, anti-icing fluid is typically applied to the aircraft after 
it leaves the hangar. Since the aircraft surfaces are dry, the volume 
of anti-icing fluid required is less than for typical anti-icing 
operations. In addition, a small amount of deicing fluid may be 
required for deicing areas of the aircraft not reached by the IR 
radiation, such as the flap tracks and elevators. The system, 
therefore, does not completely replace glycol-based fluids, but greatly 
reduces the volume required.
    Documents provided by a vendor describe use of an IR system that 
reduces the amount of Type I ADF required by up to 90 percent. Two 
large hub airports, Newark Liberty International, Newark, New Jersey, 
and John F. Kennedy International Airport, New York, use IR systems for 
some of their flights. If this technology can be applied widely, it may 
prove to be a highly effective means of reducing ADF pollution.
    EPA has not obtained substantial data documenting the amount of 
reduced glycol usage from use of IR systems, nor information on the 
availability of the technology for broader or industry-wide 
installation. EPA is interested in receiving any available data on 
those topics to documenting IR costs including (e.g., the capital costs 
of installing an IR facility, operating and maintenance costs, 
especially energy costs, glycol used during deicing and siting/sizing 
requirements for an IR facility). Because IR is not widely available or 
used, EPA does not propose to identify IR as an available technology 
for purposes of establishing ELGs. However, the Agency may reconsider 
this technology, if sufficient data support a conclusion that this 
technology is available. Specifically, EPA would require information 
proving that IR is an available technology for a sufficient percentage 
of an airports total deicing activity, as well as information on the 
amount of time required for deicing, as well as any sizing and siting 
requirements for placing an IR facility.
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 forced air 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-
mounted versions of these forced-air systems, and most systems can be 
retrofitted onto existing deicing trucks.
    A similar method to truck-mounted forced-air 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 small volume of water and glycol may be added 
to the air stream to remove dense coverings of snow and ice. Airfield 
use of the gantry system 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 environment-friendly 
products. In the ADF products category, initially the predominant 
deicers were based on ethylene glycol, whereas in recent years 
propylene glycol-based deicers, which are less toxic to mammals, have 
become more widely used. Chemical manufacturers, the aviation industry 
and the U.S. Air Force are continuing to explore development of deicers 
that could generate lower levels of pollutants compared to the glycol-
based products.
    In the field of airfield pavement deicers, several types of 
products are available as alternatives to glycol-based and urea-based 
deicers, such as potassium acetate, sodium formate and sodium acetate.
d. Transportation Research Board Report
    The Transportation Research Board (TRB), a division of the National 
Academies of Science, established a research panel to develop fact 
sheets on deicing practices to assist airports in reducing their 
deicing chemical usage and discharges. A report was prepared in 2009 
under 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 in the docket for today's proposed rule.

C. Pollutants of Concern

    Airport deicing stormwater is generated when airfield and aircraft 
deicing/anti-icing chemicals mix with snow, freezing precipitation or 
rainwater. In addition, other airport-related activities, including 
aircraft fueling and maintenance activities, may contribute pollutants 
to stormwater. Because of the difficulties in characterizing airport 
deicing stormwater, EPA evaluated pollutants detected in the 
stormwater, pollutants present in source water (i.e., prior to 
contamination with ADF), and pollutants that are present in ADF prior 
to use to determine which pollutants are present in deicing stormwater. 
The primary source of information used to identify potential pollutants 
of concern from deicing stormwater was EPA's sampling episodes, 
detailed in Section VI, as well as information presented in available 
NPDES permits and the Airport Questionnaire.
1. Aircraft Deicers
    EPA, through its review of sampling data, discussions with experts 
in the field of chemical deicers, and review of NPDES permits, 
identified over 90 pollutants associated with ADF-contaminated 
stormwater.
    EPA shortened the list of pollutants to those that were directly 
associated with aircraft deicing. This was done by reviewing 
information provided by

[[Page 44689]]

experts and excluding pollutants that were thought to be associated 
with one of the following sources; source water, aircraft and vehicle 
fueling operations, maintenance-related operations, or runoff from 
building roofs.
    Having identified pollutants that are present in airport deicing 
stormwater, the Agency next needed to consider which pollutants should 
be controlled. EPA did not consider a pollutant as a potential 
pollutant of concern if it possesses the following characteristics:
     The pollutant is present in the deicing stormwater from a 
source other than deicing chemical use;
     The pollutant is discharged in relatively small amounts 
and is neither causing nor likely to cause toxic effects;
     The pollutant is detected in the effluent from only a 
small number of airports and is uniquely related to those facilities; 
or
     The pollutant cannot be analyzed by EPA-approved or other 
established methods.
2. Airfield Deicers
    While field information on the constituents of airfield deicing and 
anti-icing chemicals is scarce, EPA determined which chemicals are 
commonly used based on the Airport Questionnaire responses. EPA did not 
identify an available technology to collect and treat pavement deicing 
pollutants, and therefore did not collect wastewater samples from 
pavement deicing discharges. Some of the most common airfield deicing 
and anti-icing chemicals include potassium acetate, sodium acetate, 
urea, sodium formate, and glycols.
3. Summary
    After reviewing these criteria, EPA identified 21 chemicals or 
parameters as pollutants of concern. Based on our knowledge of usage 
volumes, and known effects, EPA focused on the glycols in ADF fluids, 
and the ammonia in urea-based pavement deicers. Section VII.D.2 below 
discusses how EPA determined which of these pollutants of concern 
should become regulated pollutants in today's proposed rule. See the 
TDD and the EIB for further discussion of pollutants of concern.

D. Options Considered for Proposal

    Current airport deicing operations involve application of chemicals 
to both aircraft and airfield pavement. ADF may be dispersed over a 
large area due to the high-pressure spraying process used with aircraft 
as well as shearing during aircraft taxiing and takeoff. Pavement 
chemicals, while not sprayed at high pressure, are nonetheless 
similarly dispersed over a large area, namely runways, taxiways and 
aprons. The deicing chemicals mix with stormwater and are conveyed 
through a combination of overland flow and conveyance structures 
(ditches and pipes). At some airports, the contaminated stormwater is 
discharged untreated directly to waters of the United States. At other 
airports, the wastewater is treated before discharge, sent to a POTW or 
off-site waste contractor, and/or discharged to groundwater.
    In order to reduce discharges of untreated ADF wastewater for this 
industry, EPA concluded that the best available technology would need 
to include two basic components. The first component is a requirement 
to capture (collect) a certain percentage of available ADF. The second 
component is a requirement to treat the collected ADF to meet specified 
end-of-pipe discharge limitations. In many other industrial sectors, 
wastewater is typically generated and handled in confined systems such 
as reactors, pipes and pumps. Wastewater flows are carefully managed in 
these systems, and under normal operations all wastewater is directed 
to the facility's treatment system or to a POTW. In aircraft deicing 
operations, the chemicals are sprayed outdoors in a comparatively 
unconfined, usually designated setting, and there is a high likelihood 
that some pollutants will bypass the treatment system. Setting a 
minimum collection rate in the proposed rule, based on available 
technology, will require an airport to reduce significantly its level 
of uncontrolled discharges in an economically achievable manner.
1. Regulated Facilities
    Early in the regulatory development process, EPA focused on deicing 
activities at primary airports, particularly those with extensive jet 
traffic. Operators of general aviation aircraft, as well as smaller 
commercial non-jet aircraft, typically suspend flights during icing 
conditions, whereas commercial airlines operating at primary airports 
are much more likely to deice their jets in order to meet customer 
demands.
    Based on the survey results, EPA estimated that 320 primary 
commercial airports conduct deicing operations. Any effluent guidelines 
that EPA might develop for these airports must be ``economically 
achievable'' as required by the CWA, so the Agency proceeded to analyze 
various industry characteristics that would be an indicator of 
affordability for the candidate control and treatment technologies. 
This included a review of the relative sizes of various airports (based 
on annual departures), the levels of deicing activity, traffic 
characteristics (i.e., passenger vs. cargo operations), the extent of 
pollution controls and treatment in place, and the costs of various 
technologies. EPA further classified airports based on the number of 
annual jet departures. EPA found that there were some primary airports, 
typically smaller airports, with high percentages of non-jet traffic, 
and so it excluded airports with 1,000 or fewer annual jet departures 
from the scope of the proposed rule. These airports have a higher 
proportion of propeller-aircraft flights, which are typically delayed 
or cancelled during icing conditions (i.e., far less deicing takes 
place at these airports, and far less deicing fluid is used, than at 
airports serving more jets). The Agency estimated that the remaining 
218 largest primary airports account for approximately 85 percent of 
the deicing fluid used nationally, and including these airports in the 
scope of today's proposed rule is economically achievable. Moreover, 
not applying the 1,000 annual jet departure cutoff would only increase 
the volume of deicing fluid that is within the scope of today's 
proposed rule by 1 to 2 percent yet would potentially result in high 
costs to smaller airports that have minimal pollutant contributions. 
Accordingly, it is appropriate to establish this exclusion because it 
avoids projected significant adverse economic impacts on this segment 
of the industry without excluding from the national standards a 
significant pollutant load.
2. Regulated Pollutants
    As described in Section VII.C, EPA identified 21 pollutants of 
concern that stem directly from airport deicing operations. EPA 
estimates, however, that many of these pollutants, such as metals, are 
generally present in airport stormwater discharges irrespective of 
deicing activities that are taking place. These pollutants would be 
also present in discharges at airports where no deicing takes place and 
as such are beyond the scope of today's proposed rule.
    EPA determined that pollutants directly associated with aircraft 
deicing chemicals could be associated with an indicator pollutant. 
Initially, both COD and BOD5 were identified as possible 
indicator parameters. The Agency determined that COD is the best 
indicator for the following reasons:
     COD captures the oxygen demand from nitrogen and other 
organic components of the contaminated

[[Page 44690]]

stormwater that may not be represented in a BOD5 analytical 
result.
     Toxic aircraft deicing fluid additive compounds in deicing 
stormwater may have a negative and variable impact on the acclimation 
of the active cultures used in BOD5 analysis, making that 
method less accurate than a COD analysis.
     COD analyses are simple to conduct and can be measured in 
real time, compared to the 5-day test required by the BOD5 
analytical method.
     The COD analytical method does not require measurement of 
the receiving water temperature.

Further discussion of analytical methods is provided in a memorandum, 
``Regulation of COD for Airport Deicing Operations'' (DCN AD00845) in 
the docket for today's proposed rule.

    While EPA has an understanding generally of ADF composition--i.e., 
each product is a glycol-based compound with several additives--deicing 
fluid manufacturers did not provide us with information on specific ADF 
formulations. These manufacturers declined several requests to provide 
information on formulations, citing concerns about confidential 
business information. EPA has learned about a number of the additives, 
but not necessarily their concentration, from other sources. Because of 
incomplete information on these ADF additives, EPA is not proposing 
numeric effluent limits for any of these additives.
    Ammonia is the principal pollutant generated by urea-based pavement 
deicers, and EPA determined that ammonia is an appropriate indicator 
pollutant for urea-based airfield pavement deicers.
    See the TDD and EIB for further information on regulated 
pollutants.
3. Technology Options Considered for Basis of Regulation
    The effluent limitations that EPA is proposing to establish today 
are based on well-designed, well-operated collection and treatment 
systems. Below is a summary of the technology basis for the proposed 
limitations and the alternative options considered by the Agency. As is 
the case for any effluent guideline containing numeric effluent 
limitations, a facility would be able to use any combination of 
wastewater treatment technologies and pollution prevention strategies 
at the facility to meet effluent limitations.
a. Subcategorization
    EPA may divide a point source category into groupings called 
``subcategories'' to provide a method for addressing variations among 
products, processes, and other factors, which result in distinctly 
different effluent characteristics. 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 take into account technological achievability 
and economic impacts unique to that subcategory. In some cases, 
effluent limitations within a subcategory may be different based on 
consideration of these same factors, which are identified in CWA 
section 304(b)(2)(B). The CWA requires EPA, in developing effluent 
guidelines, to consider a number of different factors, which are also 
relevant for subcategorization. The CWA also authorizes EPA to take 
into account other factors that the Agency deems appropriate.
    In developing the proposed rule, EPA considered whether 
subcategorizing the aviation industry was warranted. EPA evaluated a 
number of factors and potential subcategorization approaches, including 
the presence of an on-site glycol reclamation facility, amount of ADF 
applied, number of departures, availability of land to install 
collection systems, and FAA airport classifications.
    Establishing formal subcategories is not necessary for the Airport 
Deicing category because the proposed rule is structured to address the 
relevant factors (i.e., amount of ADF applied and number of departures) 
and establish a set of requirements that encompasses the range of 
situations that an airport may encounter during deicing operations. 
Both the aircraft deicing and pavement deicing requirements include an 
airport size threshold, which excludes smaller facilities. The use of a 
performance standard, as compared to a technology specification, 
provides flexibility for airports in meeting the requirements. EPA is 
proposing to establish a set of effluent limitations that take into 
account the factors that EPA determined are relevant for 
subcategorizing this point source category.
b. Aircraft Deicing
    EPA is proposing capture and treatment requirements for spent ADF. 
EPA is not aware of an available and economically achievable technology 
that is capable of capturing 100 percent of the spent ADF, and 
therefore the Agency is focusing on collection technologies and their 
efficacy.
i. ADF Collection
    The available technologies for collecting ADF--glycol recovery 
vehicles, plug-and-pump equipment, and deicing pads--are described 
above. EPA evaluated various different combinations of these collection 
technologies for different-sized airports. See Table VII-2. These 
various options were developed to represent a wide range of collection 
requirements and corresponding costs. EPA's objective was to find a 
combination of requirements that would result in the greatest level of 
pollutant removals while still being economically achievable.
    Specifically, EPA finds that the number of aircraft departures is 
an appropriate criterion for grouping airports by size and applying 
different collection requirements to the various size groups. EPA's 
review of airline and airport deicing practices revealed that the 
amount of ADF required to deice a single aircraft varies widely. This 
is primarily due to the type of weather conditions to which an aircraft 
is exposed, or aircraft size. However, the Agency has concluded that an 
airport's overall ADF usage level directly correlates to the amount of 
wastewater generated and pollutant loadings. Because direct ADF usage 
data were not available for every airport, EPA determined that the 
annual number of aircraft departures at an airport, considered 
simultaneously with precipitation data, is a reliable predictor of ADF 
usage, based on extrapolations of data provided in the questionnaires.
    Based on the available technologies, EPA developed four ADF 
collection options as listed in Table VII-2 below as candidates for 
identification as best available technology for the collection of ADF.

    Table VII-2--ADF Collection Technology Options Considered for BAT
------------------------------------------------------------------------
               Requirement (applies
                to primary airports       Estimated
   Option      with more than 1,000      airports in    Technology basis
              annual jet departures)        scope
------------------------------------------------------------------------
1...........  20% ADF Capture         110.............  Glycol recovery
               (Airports w/10,000 or                     vehicle (GRV).
               more annual
               departures).

[[Page 44691]]

2...........  40% ADF Capture         110.............  Plug & Pump.
               (Airports w/10,000 or
               more annual
               departures).
3...........  60% ADF Capture         110 (14 @ 60% +   Centralized
               (Airports w/460,000     96 @ 20%).        Deicing Pad +
               gals. or more annual                      GRV.
               ADF usage and 10,000
               or more departures) +
               20% ADF Capture
               (Airports w/10,000 or
               more annual
               departures and less
               than 460,000 gals.
               annual ADF usage).
4...........  60% ADF Capture         218 (14 @ 60% +   Centralized
               (Airports w/460,000     204 @ 20%).       Deicing Pad +
               gals. or more ADF                         GRV.
               usage) + 20% ADF
               Capture (Airports w/
               1,000 or more jet
               departures).
------------------------------------------------------------------------
Note: All references to ADF are for normalized ADF, which is ADF less
  any water added by the manufacturer or customer before ADF
  application.

    Not all airports estimated to be in the scope of this proposed rule 
would incur ADF collection costs under it, because many of these 
airports already have ADF collection systems in place (Section VIII.C 
below). For example, of the estimated 14 airports that would have to 
meet the 60 percent ADF collection requirement in this proposal, seven 
already have installed deicing pads that would capture at least 60 
percent of the ADF.
ii. Treatment
    All airports subject to the ADF collection requirement would also 
be required to treat their ADF wastewater prior to discharge, unless 
they send this wastewater to a POTW or commercial treatment/recycle 
facility. EPA examined the four wastewater treatment technologies 
described above in Section VII.B.2 as candidates for the model BAT 
technology.
    Under this proposal, the collected ADF wastewater would need to be 
treated to a specified numeric effluent limit for COD. This limit would 
be based on the long-term averages of effluent from the treatment 
system identified at BAT (see Section VII.E.2 below).
    Further discussion of other ADF treatment technologies that EPA 
considered can be found in the TDD.
c. Airfield Pavement Deicing
    In general, airports discharge airfield pavement deicing chemicals 
without treatment due to the difficulty and expense required in 
collecting and treating the large volumes of contaminated stormwater 
generated on paved airfield surfaces. EPA is not aware of an available, 
economically achievable means for controlling these pollutants through 
collection and use of a conventional, end-of-pipe treatment system. It 
may be possible, however, to reduce or eliminate certain pollutants by 
modifying deicing practices, such as using alternative chemical deicing 
products. In particular, EPA has identified ammonia as the primary 
pollutant of concern from airfield deicing, while COD from airfield 
deicing is also a pollutant of concern, and both of these pollutants 
are a byproduct of urea-based pavement deicers.
    Accordingly, to address discharges of ammonia from airfield 
pavement, EPA identified one candidate for best available technology, 
namely, discontinuing the use of urea-based pavement deicers and using 
alternative pavement deicers instead. EPA researched product 
substitution for urea-based deicers and found that airfield pavement 
deicers other than urea are widely available in the market and that 
these alternate deicers do not produce ammonia. Eighty-nine percent of 
primary airports currently use airfield pavement deicers that do not 
contain urea. The most widely used substitute product, potassium 
acetate, accounts for 64 percent (by weight) of the annual airfield 
pavement deicer usage in the U.S. Urea stood out as an airfield deicer 
that was not predominantly used in the industry to begin with. Where it 
is still used, one of the main reasons for its use appears to be low 
cost compared to other products. Alternatives to urea are available 
that are equally effective and safe, and would greatly reduce 
discharges of ammonia from airfield deicing. These alternative airfield 
deicers include potassium acetate, sodium formate and sodium acetate. 
In suggesting these alternative deicers, EPA considered environmental 
impacts and safety issues. The Agency solicits specific data on those 
issues. EPA has also determined that the use of substitute airfield 
deicers would be economically achievable in the industry (see Section 
VIII below).
    Discontinuing the use of urea-based deicers would greatly reduce 
ammonia discharges from airfield runoff, but it would not eliminate 
them entirely because of the background levels of ammonia present in 
the general runoff from airfields. One method of ensuring that airports 
discontinue use of urea-based airfield deicers is to require them to 
certify that they use an alternative deicer. Alternatively, EPA could 
set a numeric BAT limit on ammonia based on no use of urea that 
accounts for the remaining sources of ammonia in airport discharges. 
Product substitution would also result in significant reductions of COD 
discharges. See the further discussion of this issue in the options 
selection discussion in the next section below.

E. BAT Options Selection

    EPA is proposing to identify Best Available Technology Economically 
Achievable based on Option 3 in Table VII-2. Specifically, this BAT 
option has the following three components: collection of ADF sprayed 
onto aircraft based on either GRV or deicing pads (depending on the 
amount of ADF used), treatment of the collected ADF, if appropriate, 
based on anaerobic fluidized bed technology, and certification of non-
urea-based airfield pavement deicing.
    Under Option 3, all primary airports that have over 1,000 annual 
jet departures and 10,000 or more annual departures would be required 
to collect at least 20 percent of all available spent ADF. This 
collection requirement is based on the estimated performance of glycol 
recovery vehicles. A subset of this group, those primary airports that 
have more than 1,000 annual jet departures, 10,000 or more annual 
departures and use 460,000 or more gallons of normalized ADF annually, 
would be required to collect at least 60 percent of all available spent 
ADF. (As defined at proposed Sec.  449.2, normalized ADF is ADF less 
any water added by the manufacturer or customer before ADF 
application.) This collection requirement is based on the estimated 
performance of centralized deicing pads, which are present at 8 of the 
14

[[Page 44692]]

primary airports currently meeting the departure/annualized ADF usage 
criteria noted above. Primary airports with less than 10,000 annual 
departures would not be required to collect or treat their spent 
deicing fluid.
    The proposed rule would reduce pollutant discharges by 44.6 million 
pounds annually, comprised of 39.9 million pounds of COD (from both ADF 
and urea reductions) and 4.7 million pounds of ammonia (from urea 
alone). The proposed BAT requirements for ADF would reduce the aviation 
industry's discharges of COD associated with ADF by 27.9 million pounds 
per year. This represents almost a 22 percent reduction in discharges 
of ADF-correlated COD relative to current practices used by airlines 
and airports that conduct deicing. Additionally, the proposed BAT 
requirements for airfield pavement deicing would reduce discharges of 
COD (from urea deicers) by 12.7 million pounds per year, and reduce 
discharges of ammonia by 4.7 million pounds per year.
    EPA finds that the proposed BAT technologies are generally 
available to be installed or used by those in the industry. Further, as 
will be discussed in more detail in Section VIII below, EPA has 
determined that the proposed BAT technologies are economically 
achievable. The Agency also examined the non-water quality 
environmental impacts of the rule and found them to be acceptable. The 
technology basis for each requirement--ADF collection, treatment of the 
collected ADF, and non-urea-based airfield pavement deicing--is 
discussed below.
1. ADF Collection
    For each of the four options in Table VII-2, EPA finds that the 
collection technology is widely available to the industry. See the 
summary of collection technologies used by airports in Table VII-1. EPA 
finds that for the top fourteen airports in terms of annual ADF usage, 
collection of ADF based on the use of deicing pads is technologically 
available. EPA's record indicates that at least seven of the fourteen 
airports already have installed deicing pads. For the remaining seven, 
EPA examined what appeared to be the most land-constrained airports and 
using a formula based on number of departures and number of runways, 
estimated the amount of land that would be required for installation of 
deicing pads. EPA then reviewed airport site plans provided in the 
questionnaires and determined that these constrained airports have 
sufficient land to install the necessary collection technologies. See 
the TDD for further discussion on the estimated land availability for 
deicing pads. Therefore, the Agency determined that economic 
achievability is the controlling factor in identifying which option 
represents BAT for collection of ADF.
    EPA rejected Option 2, Plug-and-Pump technology, as a basis for BAT 
for ADF collection. Although Plug-and-Pump is estimated to capture 40 
percent of spent ADF, as compared to the other options considered, the 
equipment has comparatively high operating and maintenance costs. In 
many cases, EPA estimated that Plug-and-Pump costs would be higher than 
the cost of deicing pads for a comparable airport, yet deicing pads 
achieve greater pollutant removals than Plug-and-Pump. Overall, Option 
2 achieves lower levels of pollutant removals, and it would impose 
higher costs than Option 3. Therefore, EPA finds that Option 2 is not 
the best available technology for ADF collection.
    Of the remaining options, Options 1 and 3 are economically 
achievable while Option 4 is not. Therefore, EPA proposes to identify 
Option 3 as BAT because it achieves the greatest level of pollutant 
removals among the remaining options and is economically achievable by 
the industry. The 60 percent ADF capture and treatment standard for the 
14 airports at which the largest ADF usage occurs is expected to result 
in approximately a 70 percent increase in pollutant removals compared 
to Option 1 (an increase from 26.4 million pounds to 44.6 million 
pounds of COD and ammonia removals; see Section 13 of the TDD). Thus, 
EPA projects that Option 3 will result in significantly greater 
pollutant removals but little increase in the economic impacts of the 
rule compared to Option 1. Under Option 3, only two additional airports 
would incur costs beyond Option 1 that would exceed 3 percent of 
operating revenue. These two airports are among the largest airports in 
the U.S. and therefore have the greatest ability to take on these 
additional costs without undue financial burden. See Section VIII below 
for EPA's analysis of economic achievability.
    Although EPA's analysis indicates that airports have sufficient 
land to install deicing pads, the Agency invites commenters to provide 
site-specific data and documentation on any space limitations that 
would affect an airport's ability to install deicing pads, along with 
recommendations for alternative ADF collection techniques if deicing 
pads are not feasible.
    EPA is also proposing to allow credit for facilities that might 
adopt new technologies, such as infrared heating, that use less ADF, 
but may not change the percent of ADF captured. See proposed Sec.  
449.20(b)(2)(i)(C).
2. Treatment
    The Agency proposes to identify Anaerobic Fluidized Bed (AFB) as 
the best available treatment technology for reductions of COD. EPA 
finds this technology to be widely available to the industry. It is 
currently in use at two hub airports, Albany International (New York) 
and Akron-Canton Regional (Ohio).
    The other three wastewater treatment technologies that EPA 
considered were less effective at pollutant removal compared to AFB 
systems. In addition, treating spent ADF with the mechanical methods, 
UF/RO and MVR/DC results in a concentrated waste stream that also must 
be disposed of. While these technologies have potential as a part of an 
airport's pollutant control strategy, they are not as effective as AFB 
when used as stand-alone treatment options, i.e. the pollutant removals 
they achieve are not as great as the removals achieved by AFB systems.
    The second biological control option, the aerated pond, was not 
selected as the technology basis for BAT for mainly logistical reasons. 
The ponds require large areas for installation, and the normal 
operations of these systems require treatment for many months after the 
end of the annual deicing season, before the wastewater can be 
discharged. Additionally, FAA discourages the installation of new 
stormwater detention ponds at airports, as they can be a lure for 
migratory birds. In those situations, birds and aircraft are safety 
hazards to each other. For airports with existing detention ponds, 
however, where adequate storage capacity is available, aerated pond 
systems may be able to provide efficient treatment that meets the 
standard.
    EPA has determined that AFB, as the proposed best available 
treatment technology for reductions of COD, will also achieve 
significant reductions of many of the other known pollutants associated 
with ADF, including 97 percent removal of propylene and ethylene 
glycol. The AFB treatment system removes over 75 percent of many 
phenol-ethoxylate compounds as well. Moreover, choosing to set a 
numeric limit on COD provides an approach that is both effective and is 
relatively easier and more inexpensive for airports to comply with than 
a numeric limit on glycols, the active ingredient of aircraft deicing 
fluids, would be. Monitoring costs for COD are modest relative to some 
other parameters considered by EPA. Permittees may conduct

[[Page 44693]]

monitoring with the use of portable COD meters, which provide 
immediate, real-time information on the efficacy of their treatment 
systems and facilitate timely adjustments of system operation where 
necessary. Overall, EPA's economic analysis shows that the use of AFB 
technology for treating spent ADF would be economically achievable in 
the industry. See Section VIII below for more information on economic 
achievability.
3. Airfield Pavement Deicers
    In addition to the requirements that EPA is proposing for ADF 
sprayed onto airplanes, EPA is also proposing today to identify BAT for 
the control of deicers that are applied directly to airfield pavement 
areas. Specifically, as described in Section VIII.D.3, for airfield 
pavement deicers, EPA is proposing to identify a BAT of discontinuing 
use of urea-based pavement deicers in favor of alternative, less toxic 
products that are not harmful to aircraft. Thus, BAT would be based on 
product substitution rather than treatment of the wastestream that runs 
off from airfield pavements. To demonstrate that they have used only 
non-urea based pavement deicers, permittees would be required to submit 
a certification to that effect.
    EPA considered two possible methods for eliminating discharges of 
ammonia associated with the application of urea-based pavement deicers. 
One option would be to set a performance-based numeric limit on 
discharges of ammonia that could be met by using non-urea-based 
deicers. A second option would require airports to certify that they do 
not use urea-based airfield deicing products. EPA is proposing today to 
adopt the certification option. EPA is proposing the certification 
because it ensures compliance while minimizing compliance costs. 
Certification allows a facility to demonstrate compliance with this 
product substitution-based BAT without the expense of conducting 
monitoring activities. Collecting and analyzing samples of airfield 
runoff would also present significant practical difficulties. Measuring 
ammonia discharges from airfield pavement is generally difficult due to 
the design of airport drainage systems. Wastestreams from multiple 
areas of an airport may be combined into a single pipe, which 
complicates the calculation of pollutant concentrations. In addition, 
the ``building block'' approach, which has been used to calculate 
combined wastestream concentrations for other industrial categories, is 
generally very difficult to perform at airports, due to the variability 
and unpredictability of the volume of stormwater runoff. Therefore, as 
a practical matter, a permittee who wanted to take samples and 
demonstrate compliance with a numeric limit for ammonia would need to 
show that the ammonia limit is met for all deicing runoff, not just 
airfield discharges.
    While EPA is proposing to identify product substitution as BAT, in 
order to allow flexibility to regulated facilities, the Agency is also 
proposing a compliance alternative to the certification requirement. 
This provision would accommodate facilities that might wish to continue 
using urea-based deicers and install treatment to eliminate urea-based 
ammonia discharges instead. Facilities that elect to comply using the 
compliance alternative would be required to monitor and comply with a 
proposed ammonia limit. To establish the proposed compliance 
alternative limitation for ammonia, the Agency had to take into account 
the ammonia that is a by-product of an AFB wastewater treatment system. 
This is because AFB discharges could have higher ammonia concentrations 
than that of background levels found in airfield runoff. While this 
results in a proposed compliance alternative ammonia effluent limit 
higher than concentrations in airfield runoff where AFB technologies 
are not used, the Agency estimates that these concentrations are lower 
than those from airfield pavement discharges where urea-based deicers 
are used. See ``Evaluation of Proposed Compliance Alternative Ammonia 
Limitations with Respect to Airport Deicing Stormwater Typical Ammonia 
Discharges,'' DCN AD01194, for additional discussion.
    Although EPA has developed compliance alternative ammonia effluent 
limitations for this proposal, it estimates that the cost associated 
with capturing and treating these waste streams would be prohibitively 
high for most airports. Therefore, EPA anticipates that most or all 
airports would choose the certification option rather than the ammonia 
numeric limits option in order to avoid compliance monitoring. EPA 
requests comment on implementation challenges associated with and the 
extent to which regulated facilities may select the compliance 
alternative. To the extent that comments indicate the compliance 
alternative would not be utilized, EPA might not include it in the 
final rule.

F. NSPS

    EPA evaluated which technologies should be identified as the ``best 
available demonstrated control technologies'' for purposes of setting 
new source performance standards under CWA section 306. Among the 
collection technologies that EPA considered, deicing pads capture the 
greatest level of available ADF and are widely available in the 
industry. Among the treatment technologies considered, treatment of the 
captured ADF with an anaerobic fluidized bed system represents the 
greatest level of removals of the pollutants of concern and is widely 
available for use in connection with new airports and new runways at 
existing airports. In considering economic impacts, EPA believes that a 
standard based on the use of deicing pads for ADF collection followed 
by treatment with an AFB system would not represent a barrier to entry 
for new sources in this industry. See the economic analysis discussion 
in Section VIII. Accordingly, EPA proposes to base NSPS for aircraft 
deicing on these technologies. As with the BAT requirement for existing 
sources, the proposed NSPS would require dischargers to collect 60 
percent of available spent ADF, and treat the collected wastewater to a 
specified numeric limit for COD.
    Additionally, EPA considered which technology should be considered 
the basis for setting NSPS with respect to airfield deicing. EPA 
determined that, just as with existing sources, all new sources would 
be capable of eliminating the use of urea for airfield deicing in favor 
of substitute deicing products. Product substitution represents the 
greatest level of reduction in ammonia among the available technologies 
considered and product substitution does not appear to represent a 
barrier to entry. See the economic analysis discussion in Section VIII. 
Accordingly, EPA proposes to identify elimination of urea followed by 
product substitution of non-urea-based airfield deicers as the best 
demonstrated available control technology for purposes of all new 
sources.
    Based on this identified technology, all new sources would be 
required to meet the same certification requirement proposed for BAT. 
In addition, as proposed today for existing sources, EPA proposes the 
same compliance alternative ammonia effluent limitations for new 
sources.
    For the purpose of this regulation, EPA proposes that a ``New 
Source'' would include, first, a new airport. The cost of construction 
of even small airports is significantly greater than the costs 
associated with collection and/or treatment of spent deicing fluids. 
Accordingly, meeting the new source requirements proposed today would 
not be a barrier to entry for them

[[Page 44694]]

economically. See further discussion in Section VIII below.
    In addition, EPA proposes to specify that a new runway at an 
existing airport is also a new source. EPA anticipates that few new 
airports will be constructed in the foreseeable future, and that most 
of the anticipated increase in airport capacity will be accomplished 
through the expansion of existing airports. The term ``new source'' is 
defined in EPA regulations at 40 CFR 122.2 and 122.29. EPA proposes to 
specify in the final rule that a new runway meets the terms of those 
regulations for being defined as a new source, because in EPA's view a 
new runway is a ``structure, facility or installation from which there 
is or may be a discharge of pollutants'' (Sec. Sec.  122.2 and 
122.29(a)(2)) and because a new runway is ``substantially independent 
of an existing source at the same site'' (Sec.  122.29(b)(iii)). EPA 
does not believe in general that new runways will be significantly 
integrated with existing airport facilities in a way that should 
prevent them from being identified as new sources (see Sec.  
122.29(b)(iii)). In addition, it is possible that permit authorities, 
on a case-by-case basis, would be able to deem other types of 
construction activity for aircraft movement areas to constitute a new 
source as well. For example, a permit authority might deem the 
substantial improvement or replacement of an existing runway to be a 
new source if that activity is deemed to ``totally replace the process 
or production equipment that causes the discharge of pollutants'' (see 
Sec.  122.29(b)(ii)). In all of the situations discussed above, the new 
runway or other runway construction activity would be deemed to be a 
new source only if it meets all of the criteria in the regulations 
cited above for definition as a new source.

G. BPT and BCT

    The CWA provides for two increasingly stringent levels of 
technology-based controls on discharges of pollutants. See EPA v. 
National Crushed Stone Association, 449 U.S. 64 (1980). BPT represents 
the first level of control applicable to all pollutants. BCT and BAT 
represent the second level of control for conventional and toxic/
nonconventional pollutants, respectively. EPA considered whether in 
this rule, it was necessary to establish BPT and BCT limits, given that 
ADF and pavement deicing fluid will be controlled at the more stringent 
BAT level. Because the BAT controls in this rule also control the same 
pollutants as would be controlled by BPT or BCT limits, it is not 
necessary for EPA to analyze options and propose BPT and BCT effluent 
limitation guidelines for the Airport Deicing Category. EPA recognizes 
that it has proposed, in the past, all three levels of control, BPT, 
BCT and BAT for various industries even where the same pollutants and 
wastestream were at issue. In this rule however, the Agency solicits 
comments on this approach because it represents significant resource 
savings for EPA in terms of analysis and rulemaking process while not 
sacrificing any environmental protection. Additionally, EPA is not 
establishing BCT limitations for this industry because these 
limitations apply only to conventional pollutants such as 
BOD5 and total suspended solids and this effluent guideline 
regulates only non-conventional pollutants (chiefly COD and ammonia).

H. Pretreatment Standards

    Some airports in the U.S. discharge ADF-contaminated runoff to 
POTWs. EPA does not have any information indicating that POTWs 
currently have problems of pollutant pass-through, interference or 
sludge contamination stemming from these discharges. For this reason, 
the Agency is not proposing PSES or PSNS. EPA is aware that high 
concentration or ``slug'' discharges of deicing wastewater can create 
POTW upset, and many of the airports that discharge to POTWs have 
airport-specific requirements on allowable BOD5 or COD 
discharge loading per day. They may also have requirements for 
discharging at various concentration levels over time. Airports usually 
meet this requirement by storing deicing stormwater in ponds or tanks 
and metering the discharge to meet the POTW permit requirements.

I. Compliance Costs

1. Overview
    EPA estimated industry-wide compliance costs for this proposed 
rule. This section summarizes EPA's approach for estimating compliance 
costs, while the TDD provides detailed information on these estimates. 
All final cost estimates are expressed in terms of 2006 dollars and 
represent the cost of purchasing and installing equipment and control 
technologies, annual operating and maintenance costs, and associated 
monitoring and reporting requirements.
    EPA estimated compliance costs associated with today's proposal 
using data collected through survey responses, site visits, sampling 
episodes, specific airport requests and information supplied by 
vendors. As applicable, EPA estimated the costs for an airport to 
comply with today's proposal initially, as well as maintaining 
equipment and performing required monitoring or other activities to 
demonstrate ongoing compliance. These costs may include upgrading/
installing and operating a collection system and/or a treatment system, 
chemical analysis for compliance as well as the costs associated with 
substituting potassium acetate in place of urea as a chemical airfield 
deicer. EPA's cost estimates represent the incremental costs for a 
facility when its existing practices would not lead to compliance with 
today's proposed 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 
respondents (149 facilities), where each facility was treated as a 
``model'' airport. Because the questionnaire respondents 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 with information on three 
consecutive deicing seasons (2002-2005) for each of the model 
facilities. 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 aspects of an 
airport's operation changed over the three-year period, EPA used the 
most recent information. For example, if an airport installed a deicing 
pad in 2005, EPA's costing estimates would reflect any incremental 
changes required above the current ADF collection rate, to meet the 
collection rate in the proposed rule.
2. Approach for Developing Aircraft Deicing Costs
    Under this proposed rule, an airport would be required to collect a 
percentage of its sprayed ADF, and treat that wastewater to comply with 
numeric effluent limitations. EPA estimated the costs for an airport to 
comply with collection and treatment requirements, as well as 
performing required monitoring to demonstrate compliance. These costs 
include estimates of upgrading airports' current collection systems, 
installing the required technology to treat the wastewater, maintaining 
equipment and conducting chemical analyses for compliance.

[[Page 44695]]

    EPA first established existing conditions for each model airport 
based on information and site plans submitted as part of the Airport 
Questionnaire. EPA then determined what upgrades, if any, would be 
required to comply with today's proposal. In general, when an airport 
lacked a comparable collection system to the one used as the basis for 
the options considered in today's proposal, EPA included costs for 
installation/implementation of one of the following collection 
technologies: GRVs, GRVs used in conjunction with plug-and-pump 
systems, or deicing pads.
    For estimating wastewater treatment costs, EPA assumed costs for 
storage of anticipated volumes of collected ADF. Airport-specific costs 
were assessed for storage options, including ponds, permanent tanks 
(both underground and aboveground), or mobile/temporary fractional 
distillation tanks.
    EPA based its selection of a particular storage option on an 
airport's current storage facilities, and on what would be the easiest 
for that airport to implement. The Agency assumed that it is likely 
that an airport with a pond already in place would use that for 
storage, as opposed to constructing permanent tanks; and assumed that 
an airport with limited available land would install an underground 
tank.
    Based on questionnaire responses and engineering judgment, EPA 
assessed the current level of treatment for each model facility that 
discharges directly to waters of the U.S. Except in limited 
circumstances, when a model facility was determined to require 
additional treatment, EPA assigned costs associated with installing an 
AFB treatment system as the most likely means of compliance.
    Of the direct discharging model facilities that were modeled for 
treatment costs, EPA assumed that approximately five percent would use 
off-site hauling for waste treatment, based on the Agency's estimate 
that this percentage will find this choice to be the most cost-
effective alternative. These facilities have relatively limited deicing 
operations and off-site hauling is more cost-effective than installing 
an on-site biological treatment system. Additionally, an on-site 
biological treatment system would require a regular wastestream flow in 
order to keep the biological system functioning properly, and an 
airport with limited deicing operations may have trouble maintaining a 
regular wastestream.
    EPA recognizes that an airport may decide to use a POTW rather than 
directly discharging its wastewater. While this may be a lower cost 
alternative in some cases, EPA did not estimate costs for such a 
change, because the Agency does not have enough information about the 
capacity of specific POTWs to receive these volumes of wastewater. EPA 
also was not able to determine if a specific POTW would be unwilling to 
accept the wastewater from a particular airport, and for other reasons, 
such as inconsistencies with its future growth plans. For these 
reasons, EPA did not include this alternative in its model.
    An airport that has upgraded its collection and treatment systems 
may have additional monitoring costs. While the permit authority 
determines the required monitoring frequency for an individual 
permittee, EPA estimated the overall costs of the anticipated 
monitoring requirements associated with the proposed rule. EPA 
estimated the cost per airport for the ADF collection requirement, and 
the cost of analyzing COD in the treated effluent. For costing 
purposes, EPA assumed that an airport would take a 24-hour composite 
sample and analyze that for COD, and perform that analysis five times 
per week throughout the deicing season. EPA made a similar assumption 
for purposes of computing the proposed weekly average effluent 
limitation. As a conservative estimate, EPA assumed a six-month deicing 
season for all modeled facilities. Additionally, EPA assumed that the 
model facility would perform an assessment of their collection system 
once every permit cycle.
3. Approach for Estimating Airfield Pavement Deicing Costs
    Under today's proposal, in addition to the requirements set forth 
for capture/treatment of aircraft deicing fluid, an airport would be 
required to certify it uses non-urea-based airfield deicers. Through 
the results of the Airport Questionnaire, EPA learned that 29 model 
facilities (a subset of the 149 model facilities referenced above) use 
urea for airfield pavement deicing. As detailed in Section VII.D.3, EPA 
based its certification requirement on product substitution. EPA 
calculated the cost for these 29 model facilities to substitute the 
urea used for deicing 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 switch to potassium 
acetate, specifically because that product accounts for 64 percent of 
the applied chemical airfield deicer usage (by weight) in the U.S.
    EPA identified 16 airports that used both urea and potassium 
acetate for airfield deicing, and 8 of these airports provided usage 
data. The Agency calculated that the average cost of urea was $274.24/
ton and the average cost of potassium acetate was $3.16/gallon. The 
questionnaire responses indicated that between 2002 and 2005 an average 
of over 7 million pounds of urea were used annually, costing an 
estimated $1.06 million.
    Urea deicers are applied at a different rate to have an efficacy 
equivalent to potassium acetate. EPA had to determine what amount of 
potassium acetate would be required to replace the estimated 7 million 
pounds of urea used annually. EPA could not locate any information on 
the relative application rates between potassium acetate and urea 
directly; however, we did develop a comparison to sodium acetate, 
another solid pavement deicer. Both urea and potassium acetate 
application rates vary depending on the weather conditions and the 
thickness of the ice layer at the time of application. Using the 
information available, EPA assessed comparable application rates and 
costs between urea and potassium acetate to treat 1,000 ft \2\ of area 
for thin ice conditions at 32 [deg]F and 1-inch-thick ice conditions at 
less than 10 [deg]F. DCN AD00843 provides additional details about the 
calculations on product substitution.
    Using the reported urea usage in the Airport Questionnaire, EPA 
estimated the airfield area that was annually deiced at each model 
facility. Finally, using the estimated model facility airfield area in 
conjunction with the estimated $2.32/1,000 ft\2\ cost of potassium 
acetate, EPA was able to calculate the cost per model facility to 
perform airfield deicing with potassium acetate. This cost was compared 
to the questionnaire reported urea costs to determine the incremental 
costs of switching chemical airfield deicers.
4. Calculation of National Costs
    EPA categorized all of the costs as either capital costs (one-time 
costs associated with planning or installation of technologies), 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).
    For each model facility, EPA calculated an annualized cost based on 
the sum of all the associated O&M costs as well as amortized capital 
costs. Capital costs were amortized over the lifespan of the capital 
improvement, as reported by the facility. No capital costs were 
amortized over more than 20 years, even if an estimated lifespan of an 
airport exceeded 20 years. Finally, EPA

[[Page 44696]]

combined the amortized costs with the annual O&M to calculate the total 
annual cost of the regulation for that model facility.
    EPA then utilized statistical weights assigned to each of the 149 
model facilities in order to calculate a national estimated cost of 
$91.3 million for complying with the proposed rule. Further discussion 
of all of the calculations discussed above can be found in the TDD.

J. Approach to Estimating Pollutant Reductions

1. Overview
    The pollutants of concern associated with airfield and aircraft 
deicing and anti-icing chemicals are discussed earlier in this 
preamble. These chemicals commingle with stormwater and they 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. The oxygen demand 
of compounds can be measured as five-day biochemical oxygen demand 
(BOD5) and chemical oxygen demand (COD), or calculated as 
theoretical oxygen demand (ThOD).
    Pollutant loadings from airport deicing operations are challenging 
to estimate because they are highly variable and airport-specific. 
Because 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 airport's climate. In addition, the amount of applied 
chemical that is discharged to surface water is airport specific, based 
on the existing stormwater separation, collection, and/or containment 
equipment present at each airport.
    Due to the variable nature of these pollutant loads, EPA developed 
an estimation methodology based on the usage of ADF and airfield 
chemicals at the airports responding to the survey questionnaires. The 
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.
2. Sources and Use of Available Data
    While developing the pollutant loading models, EPA considered the 
following data sources:
     Pavement deicing chemical usage/purchase information for 
the 2002/2003, 2003/2004, and 2004/2005 deicing seasons, as reported by 
airport authorities in the Airport Deicing Questionnaire;
     ADF purchase information for the 2002/2003, 2003/2004, and 
2004/2005 deicing seasons, as reported by air carriers in the 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;
     Weather information for each airport from National Oceanic 
and Atmospheric Administration (NOAA), including temperature, freezing 
precipitation, and snowfall data;
     Existing airport stormwater collection and containment 
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 episodes of airport 
deicing operations.
a. Baseline Loading Calculations
    To estimate pollutant loadings from deicing operations, EPA 
analyzed airports' questionnaire responses and information provided 
during the site visits. The Agency estimated the total amount of 
pavement deicing chemicals and ADF used based on data collected in the 
Airport and Airline Questionnaires.
    In the Airport Questionnaire, EPA requested that airport 
authorities report the purchase/usage amount, concentration, and brand 
name of pavement deicing materials. EPA evaluated each reported 
chemical to determine the most appropriate way to estimate the average 
amount used over the past three winter seasons. EPA also requested the 
purchase amount, concentration, and brand names of ADF chemicals in the 
Airline Questionnaire.
    The responses to the Airline Questionnaire provided sufficient data 
to estimate ADF usage at 56 airports. In some cases, data were not 
available for every airline operating at a particular airport. In these 
instances, 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 
(departures) at the reporting airlines and the total amount of airport 
operations. In addition to the ADF data reported in the Airline 
Detailed Questionnaire, 10 airports reported total gallons of ADF usage 
to EPA in their comment section of the Airport Deicing Questionnaire. 
These ADF data were combined with the ADF data reported in the Airline 
Deicing Questionnaires, resulting in estimates of total ADF usage for 
66 airports.
    Using the Airline and Airport Questionnaire ADF purchase data, 
airport departure data, and climate data, EPA developed a relationship 
between the estimate of amount of ADF used, the climate and size of 
each airport. EPA used this equation to estimate the total gallons of 
ADF used at airports that did not have available ADF data in the 
Airport or Airline Questionnaires.
    Once the amount of ADF applied at each airport had been determined, 
EPA needed to determine the amount of ADF available for direct 
discharge. EPA assumes that 80 percent of applied Type I and Type II 
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 
remaining 90 percent adheres to the plane. (See the TDD for more 
information on these estimates.) The total amount of applied ADF was 
multiplied by the appropriate percent available for discharge to 
determine the amount of ADF that is available for discharge. Note that 
compliance capture requirements in the proposed 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 estimated baseline collection rate, would result in the total 
amount of discharged ADF. After excluding the ADF removed via baseline 
capture, EPA calculated the amount of COD and BOD5 loading 
associated with the degradation of the applied deicing/anti-icing 
chemicals. EPA later decided that COD was a more accurate and practical 
indicator to regulate than BOD5 (see the discussion in 
Section 7 of the Technical Development Document).
    Airfield pavement deicing chemicals are applied at various airside 
areas where differing activities occur. Theoretically, the 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 percent 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 discharged at a particular airport is

[[Page 44697]]

difficult without performing a detailed study at the airport. EPA has 
not received any such detailed studies, nor other information from 
airports indicating that pavement deicers are absorbed into soil during 
the deicing season. Therefore, the Agency assumed for this rulemaking 
that 100 percent of pavement deicers are discharged to surface waters. 
This means the estimates of baseline pollutant loadings and removals 
associated with pavement de-icing are upper bound estimates.
    EPA calculated the amount of pollutant loadings discharged to 
surface waters by using standard published chemical information and 
stoichiometric equations. This methodology is preferable to using 
empirical data because it can be applied to all deicing chemicals being 
used by the aviation industry. In addition, this methodology allows for 
a clear presentation of the calculations and assumptions used. EPA 
confirmed the validity of the COD concentrations for propylene glycol 
and ethylene glycol calculated using this methodology against the 
available empirical data. See Section 10 of the TDD for more 
information on calculations of baseline loadings due to airfield 
deicers.
b. Calculation of Pollutant Removals
    EPA estimated the amounts of COD that would be reduced by the 
proposed rule, by estimating the existing capture and treatment levels 
at individual airports and comparing that to the levels that would be 
required by the proposed rule. If a particular airport would be subject 
to a collection requirement of 20 percent under the proposed rule and 
it currently is estimated to capture a greater proportion, then no load 
removals were estimated for that airport. Additionally, if an airport 
was estimated to use urea for pavement deicing, EPA assumed that the 
airport would use product substitution to meet the proposed effluent 
limit. The ammonia and COD loads associated with urea were calculated 
and then EPA computed the total load reduction by subtracting the 
ammonia loadings and the COD loadings of the substitute product, 
potassium acetate. (Although some studies indicate that alternative 
pavement deicers can be toxic to aquatic organisms, the combined impact 
of the COD content, toxicity, and nutrient content of urea is greater 
than effects associated with alternative pavement deicers.)
    These calculated loading reductions, for both airfield and aircraft 
deicing chemicals, were then extrapolated by multiplying the direct 
discharge loads or load removals by the airport survey weighting 
factors to determine national loads for the entire industry for 
baseline and each regulatory scenario. EPA estimates the total annual 
pollutant removal for the proposed rule at 44.6 million pounds, 
comprised of 39.9 million pounds of COD and 4.7 million pounds of 
ammonia. The pollutant removal estimates for the other regulatory 
options range from 26 million pounds to 46 million pounds.

K. Approach to Determining Long-Term Averages, Variability Factors and 
Effluent Limitation Guidelines and Standards

    This section describes the statistical methodology used to develop 
the proposed daily maximum and maximum for weekly average effluent 
limitations for BAT and new source performance standards for COD. EPA 
also used the same statistical methodology to develop the daily maximum 
limitation/standard for ammonia that is a proposed compliance 
alternative when urea is applied to runways. For simplicity, the 
following discussion uses the term ``limitation'' to refer to effluent 
limitations, standards, and the compliance alternative. EPA has 
proposed the same limitations for each level of recovery requirements, 
because the treatment technology and performance are the same 
regardless of the amount of fluid recovered.
    The following sections describe the data selection criteria; the 
statistical percentile basis of the proposed limitations; rationales 
for proposing certain limitations; the calculations; the recommended 
long-term average value for treatment operations; and the engineering 
evaluation of the model technology's ability to achieve the levels 
required by the proposed limitations.
1. Criteria Used To Select Data as the Basis of the Proposed 
Limitations
    Typically, in developing effluent limitations for any industry, EPA 
qualitatively reviews all the data before selecting a subset as the 
basis of the limitations. EPA typically uses four criteria to assess 
the data. One criterion generally requires that the influent and 
effluent represent only wastewater from the 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 influent at sufficient concentrations to 
evaluate treatment effectiveness. A third criterion generally requires 
that the facility must have the technology and demonstrate good 
operation. A fourth criterion typically requires that the data cannot 
represent periods of treatment upsets or shutdown and start-up periods. 
(Shutdown periods can result from upset conditions, maintenance, and 
other atypical operations.)
    EPA has adapted the application of the fourth general criterion for 
data corresponding to start-up periods to reflect some unique 
characteristics of treating discharges from aircraft deicing 
operations. Most industries incur start-up conditions only during the 
adjustment period associated with installing new treatment systems. 
During this acclimation and optimization process, the concentration 
values tend to be highly variable with occasional extreme values (high 
and low). After this initial adjustment period, the systems should 
operate at steady state for years with relatively low variability 
around a long-term average. Because start-up conditions reflect one-
time operating conditions, EPA generally excludes such data in 
developing the limitations. In contrast, EPA expects airports to 
encounter start-up operations at the start 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 is proposing to include start-up data in 
the data set used as the basis of the limitations. However, through its 
application of the other three criteria, EPA would exclude extreme 
conditions that do not demonstrate the level of control possible with 
proper operation and control even during start-up periods.
    In part, by retaining start-up data for limitations development, 
the limitations will be achievable because EPA based these limits on 
typical treatment during the entire season. Once the treatment system 
reaches steady state, EPA expects a typically well-designed and 
operated system to run continuously until the end of the deicing 
season. Conversely, EPA might determine that systems that operated only 
during relatively short periods, such as during each winter storm event 
(i.e., of only several days duration), might be poorly operated because 
the model technology requires more time to reach steady state. In other 
words, it would be ineffective and disruptive to turn the system on and 
off throughout the deicing season, particularly for biological systems, 
such as the model technology, and EPA may reject data if it determines 
that it reflects this type of operation.
2. Data Used as Basis of Proposed Limitations
    Of the effluent data available to EPA, 2,562 concentration values 
for COD and

[[Page 44698]]

5 concentration values for ammonia met the requirements in the criteria 
and are the basis of the proposed limitations. The concentration values 
are measurements of effluent collected from Albany Airport's anaerobic 
treatment system. The 2,562 COD values were collected by the airport 
during its daily monitoring of COD over ten deicing seasons (i.e., 
December 1, 1999 through April 10, 2009). The five ammonia values were 
collected by EPA during its sampling episode (February 5 through 
February 9, 2006). (As explained in Section VII.E.3, EPA transferred 
the ammonia data from the anaerobic fluidized bed (AFB) technology 
because an AFB system by design creates ammonia as a by-product of 
wastewater treatment. Consequently, AFB discharges could have higher 
ammonia concentrations than typically found in airfield runoff when 
urea is not present. If the treated aircraft deicing effluent then were 
discharged through the same pipe as the runway runoff, the airport 
might have difficulties complying with the ammonia limitation.)
    For the final rule, EPA might further explore factors contributing 
to variability observed in the available data, assess whether some 
modes of operations do not reflect the performance expected from the 
model technology (as required by criterion 3), and thus decide whether 
to exclude any of the corresponding data as the basis of any 
limitation.
    EPA is soliciting additional data on airport discharges (see 
Section XIV for a detailed request for data). When applying the data 
selection criteria for the final limitations, EPA will consider new 
information from commenters and other sources. Consequently, EPA may 
reach new conclusions about whether some or all of the proposal data 
should be included or excluded as the basis of the final limitations; 
and/or revisions to its statistical approach are appropriate. As a 
result of its evaluation of the new information, EPA may promulgate 
final limitations that are more or less stringent than the proposed 
limitations.
3. Statistical Percentile Basis for Limitations
    EPA uses a statistical framework to establish limitations that 
facilities are capable of complying with at all times. Statistical 
methods are appropriate for dealing with effluent data because the 
quality of effluent, even in well-operated systems, is subject to a 
certain amount of fluctuation or uncertainty. Statistics is the science 
of dealing with uncertainty in a logical and consistent manner. 
Statistical methods together with engineering analysis of operating 
conditions, therefore, provide a logical and consistent framework 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 derived numerical values for its proposed 
daily maximum limitations and weekly average limitations.
    The statistical percentiles are intended, on one hand, to be high 
enough to accommodate reasonably anticipated variability within control 
of the facility. The limitations also reflect a level of performance 
consistent with the CWA requirement that these limitations be based on 
the best technologies that are properly operated and maintained.
    In establishing daily maximum limitations, EPA's objective is to 
restrict 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 normal operations. This variability 
means that at certain times airports may discharge at a level that is 
greater than the long-term average. This variability also means that 
airports may at other times discharge at a level that is considerably 
lower than the long-term average. To allow for possibly higher daily 
discharges, EPA has established the daily maximum limitation at a 
relatively high level (i.e., the 99th percentile). EPA has consistently 
used the 99th percentile as the basis of the daily maximum limitation 
in establishing limitations for numerous industries for many years and 
numerous courts have upheld EPA's approach.
    EPA has not promulgated weekly average limitations for other 
industries, and thus, is soliciting comment on its approach for this 
industry. Because EPA typically establishes limitations based upon 
statistical percentile estimates, it is proposing to do so for the 
weekly average limitation. In its derivation of the weekly average 
limitation for COD, EPA used an estimate of the 97th percentile of the 
weekly averages of the daily measurements. This percentile basis is the 
midpoint of the percentiles used for the daily maximum limitation 
(i.e., 99th percentile of the distribution of daily values) and the 
monthly average limitation (i.e., 95th percentile of the distribution 
of monthly average values). Courts have upheld EPA's use of these 
percentiles, and the selection of the 97th percentile is a logical 
extension of this practice. Compliance with the daily maximum 
limitation is determined by a single daily value; therefore, EPA 
considers the 99th 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 
limitation is based upon more than one daily measurement and averages 
are less variable than daily discharges, EPA has determined that 
facilities should be capable of controlling the average of daily 
discharges to avoid extreme monthly averages above the 95th 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 measurement. However, the airport would monitor for a shorter 
time and thus would have fewer opportunities to counterbalance highly 
concentrated daily discharges with lower ones. For this reason, EPA is 
proposing and seeks comment on the choice to use a larger percentile 
for the weekly average limitation than the one used for the monthly 
average limitation. Consequently, EPA is proposing the 97th percentile 
as an appropriate basis for limiting average discharges on a weekly 
basis. EPA also considers this level of control in avoiding extreme 
weekly average discharges to be possible for airports using the model 
technology.
4. Rationale for Proposing Limitation on Weekly Averages 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 average limitation for 
the circumstances associated with monitoring during the deicing season. 
In this situation, the weekly average limitation would apply to every 
week that the treatment system operates during the deicing season.
    When it establishes monthly average limitations, 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 limitation requires facilities to provide on-going 
control that complements controls imposed by the daily maximum 
limitation. To meet the monthly average limitation, a facility 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 monthly average value at or 
below the monthly average limitation.
    The deicing season is unlikely to start at the 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

[[Page 44699]]

months. Increasing or decreasing monitoring frequency does not affect 
the statistical properties of the underlying distribution of the data 
used to derive the limitations. However, monitoring less frequently 
theoretically results in average values that are more variable. For 
example, monthly average values based on 10 monitoring samples per 
month would be (statistically) expected to include some averages that 
are numerically larger (as well as some that are numerically smaller) 
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 otherwise well-
operated and controlled system. In other words, because it was not 
monitoring as frequently, the airport would have fewer opportunities to 
counterbalance high concentrations with lower values.
    A weekly average limitation preserves EPA's intent for an 
additional restriction beyond the daily maximum limitation that 
supports EPA's objective of having airports control their average 
discharges at the long-term average. EPA is proposing and soliciting 
comment on use of a weekly average instead of a monthly average 
limitation because it appears to be a better fit for this industry from 
a monitoring perspective. However, two factors may warrant another 
approach in the final rule. First, a week may be too short a period to 
ensure that airports will optimize their systems appropriately over a 
longer period to achieve the long-term average. Second, the industry 
and permit writers are unlikely to have experience with weekly average 
limitations and may prefer other alternatives. Other approaches may 
include the monthly average limitation and/or the annual average 
limitation sometimes used for intermittent dischargers in other 
industries. For example, for the Pulp, Paper and Paperboard Category 
(40 CFR Part 430), EPA promulgated an annual average limitation that 
was set equal to the value of the long-term average derived from the 
data used to develop the daily maximum and monthly average limitations 
for continuous dischargers. (It does not have an allowance for 
variability.) EPA solicits comment on whether weekly average 
limitations, monthly average limitations or some other approach would 
be appropriate to ensure that airports have well-operated, maintained, 
and controlled treatment systems that discharge at a level consistent 
with the long-term average.
5. Rationale for Proposing a Limitation Only for Daily Discharges of 
Ammonia in Effluent Discharges
    EPA believes that it appropriate to rely on 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 related to monitoring for 
COD). Unlike COD, EPA is not proposing a weekly ammonia effluent 
limitation. The technology basis for the COD effluent limitations would 
operate throughout the deicing season with continuous discharges 
allowing for weekly monitoring. In contrast, urea is 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. Consequently, it would be difficult to 
assume a single value for the monitoring frequency that could 
reasonably be applied to all airports, regardless of climatic 
conditions. In developing the average limitations, this assumed 
monitoring frequency is used in the statistical calculations. Although 
EPA has concerns about establishing average limitations on a national 
basis, a permit authority may choose to establish weekly or monthly 
average limitations for a specific airport, and would presumably assume 
a monitoring frequency based upon local climatic conditions.
    Additionally, EPA expects airports to select product substitution 
(i.e., non-urea deicers) rather than the compliance alternative that 
requires collection and treatment of runway runoff. Thus, it is 
possible that no airports will be subject to any limitation on ammonia 
discharges. For the final rule, after reviewing any supplementary 
information and comments, EPA may reevaluate whether weekly and/or 
monthly average limitations are necessary for proper control of 
ammonia.
6. Calculation of Limitations for COD and Ammonia
    For COD, EPA used nonparametric statistical methods to estimate the 
percentiles used as the basis of the daily maximum and weekly average 
limitations. A simple nonparametric estimate of a particular percentile 
(e.g., 99th) of an effluent concentration data set is the observed 
value that exceeds that percent (e.g., 99) of the observed data points.
    For the proposed daily maximum limitation for COD, EPA used the 
nonparametric method to derive a 99th percentile of the more than 1200 
daily measurements for each unit, and then set the proposed limitation 
equal to the median of the two 99th percentile estimates, or 271 mg/L. 
The median is, by definition, the midpoint of all available data values 
ordered (i.e., ranked) from smallest to largest. In this particular 
case, because there are two units, the median is equal to the 
arithmetic average (or mean).
    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 (to be consistent with the assumed 
monitoring costs, although permit authorities may specify different 
monitoring requirements). EPA then used the nonparametric method to 
derive a 97th percentile of the more than 200 weekly averages for each 
unit, and set the proposed limitation equal to the median of the two 
97th percentile estimates, or 154 mg/L.
    For comparison purposes, EPA tentatively estimated 112 mg/L as the 
95th percentile of the monthly averages using a statistical model based 
upon the lognormal distribution. If EPA were to establish a monthly 
average limitation, it would examine the statistical properties of the 
data to determine the appropriate model and statistical assumptions.
    For ammonia, EPA used a parametric approach in estimating the 99th 
percentile based upon the data collected during EPA's 4-day sampling 
episode. The calculations assume the ammonia concentrations can be 
modeled by a lognormal distribution. EPA's selection of parametric 
methods, such as the lognormal distribution, in developing limitations 
for other industries is well documented (e.g., Iron and Steel (40 CFR 
Part 420), Pulp, Paper and Paperboard (40 CFR Part 430), Metal Products 
and Machinery (40 CFR Part 438) categories). Variance estimates based 
upon parametric methods can be adjusted for possible biases in the 
data. The proposed limitation of 14.7 mg/L includes such an adjustment 
for possible bias from positive autocorrelation. When data are 
positively autocorrelated, it means that measurements taken close 
together in time are more closely interrelated than measurements taken 
farther apart in time. The adjusted variance then better reflects the 
underlying variability that would be present if the data were

[[Page 44700]]

collected over a longer period. For comparison purposes, EPA estimated 
values of 9.75 and 6.98 mg/L for the weekly average limitation and 
monthly average limitation.
7. Derivation of Long-Term Average for COD and Ammonia: Target Level 
for Treatment
    Due to routine variability in treated effluent, an airport that 
discharges 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 frequent values exceeding the limitations. For 
this reason and as noted previously in this section, EPA recommends 
that airports design and operate the treatment system to achieve the 
long-term average that it derived for the model technology. Thus, a 
well-operated and designed system will be capable of complying with the 
proposed limitations.
    For COD, EPA recommends that airports target treatment systems to 
achieve the long-term average value of 41 mg/L, which is the median of 
the 50th percentiles, of 37 and 45 mg/L, of the daily values from the 
two units. The daily allowance for variability, or the ratio of the 
limitation to the long-term average, is 6.6. (EPA usually refers to 
this allowance as the ``variability factor.'') In other words, the 
daily maximum limitation of 271 mg/L is about seven times greater than 
the long-term average achievable by the model technology. The weekly 
variability factor is 3.8.
    For ammonia, EPA derived its recommended long-term average value of 
5.24 mg/L from the (statistical) expected value of the lognormal 
distribution. The daily maximum limitation of 14.7 mg/L is about three 
times greater than the 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 concentrations of 
ammonia to have similar variability to what is being treated (i.e., 
COD). In contrast 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. EPA requests 
additional data that reflect ammonia discharges during start-up 
operations.
8. Engineering Review of Proposed Limitations
    In conjunction with the statistical methods, EPA performs an 
engineering review to verify that the limitations are reasonable based 
upon the design and expected operation of the control technologies and 
the facility conditions. During the site visit and sampling trip at the 
Albany treatment plant, EPA confirmed that the airport used the model 
technologies, specifically AFB. EPA subsequently contacted the plant 
personnel to obtain more information about the installation and 
operation of the model technologies. EPA used this engineering 
information to select the subset of data from which to develop the 
proposed limitations. In doing so, EPA excluded one extreme value 
because plant personnel considered it to be atypical, and likely, the 
result of high solids content. Plant personnel also noted that they had 
removed and reinstalled the carbon for one unit prior to the last 
deicing season. Because the performance for the next deicing season was 
among the best demonstrated for this system EPA concluded that the data 
with the new carbon characterized variability that operators could 
expect from periodic maintenance for long-term operation.
    As part of this engineering review, EPA concluded that the values 
of the limitations were consistent with the levels that are achievable 
by the model technologies. Next EPA compared the value of the proposed 
limitations to the data values used to calculate the limitations. None 
of the data selected for ammonia were greater than its proposed daily 
maximum limitation which supports the engineering and statistical 
conclusions that the limitation value is appropriate. Because of the 
statistical methodology used for the COD limitations some values were 
greater than the proposed limitations. Of the 2,562 data points 
selected for COD, 27 data points had daily values that were greater 
than the proposed daily maximum limitation of 271 mg/L. Of the 460 
weekly averages, 14 averages had values that were greater than the 
proposed weekly average limitation of 154 mg/L. Of those 14 averages, 
11 were during weeks when the unit also had one or more daily values 
that were greater than the daily maximum limitation. EPA considered, 
from an engineering perspective, whether any factors were likely to 
have led to the larger daily discharges of COD. These factors included 
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 seasons. In evaluating influent concentrations, EPA found that 
influent concentrations were generally well-controlled into the 
treatment plant. In general, the treatment systems adequately treated 
even the extreme influent values, and the high effluent values did not 
appear to be the result of high influent discharges. 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 appear to provide adequate allowance for start-up 
operations.
    For the final rule, EPA may further assess the range of the 
operating conditions and resulting performance of the treatment units 
used at the Albany airport that were the basis of the COD limitation. 
For example, EPA may contact this airport about the 27 COD values 
greater than the proposed daily maximum limitation. In the final rule, 
EPA may consider adjustments (upward or downward) to the limitations to 
ensure that they adequately reflect normal operations of the model 
technology. These final limitations may require some dischargers to 
improve treatment systems and/or operations to meet consistently the 
effluent limitations. EPA determined that this consequence is 
consistent with the Clean Water Act statutory framework, which requires 
that discharge limitations reflect the best available technology.

L. Complying With Regulatory Requirements

1. Compliance Dates
    EPA proposes that the compliance date for today's proposed 
requirements will be 30 days after promulgation. Permits issued after 
this date will need to include limits consistent with the final rule.
2. Determination of Number of Annual Departures
    Airports, in determining whether they are subject to this proposed 
rule, will need to refer to the number of annual departures over a 
five-year period prior to submittal of a permit application or NOI. Air 
traffic controllers tabulate departure data, which are then compiled in 
the BTS T-100 database (available at http://transtats.bts.gov). These 
data, along with ADF usage data collected pursuant to proposed Sec.  
449.20(a), will allow permittees, permit authorities, and the public to 
easily determine which ADF collection requirements would apply to a 
particular airport.

[[Page 44701]]

3. Alternate Means of Demonstrating Compliance
a. ADF Collection Requirement
    EPA is aware that the ADF collection requirement differs from 
traditional end-of-pipe effluent limitations with regard to a mechanism 
for demonstrating compliance. Compliance with the collection 
requirement cannot be determined through end-of-pipe sampling and 
analysis. Additionally, the amount of ADF available for collection can 
vary depending on the weather and icing conditions at the time of 
application. EPA is proposing three procedures for demonstrating 
compliance with the ADF collection requirement.
    The first procedure would require an airport to certify to the 
permitting authority that it is operating its collection system in 
accordance with specifications for the applicable technology described 
at proposed Sec.  449.20(b)(1). The proposed specifications describe 
operating practices for the technologies. As long as these technologies 
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.
    It is not practical for EPA to provide operating specifications for 
all potential collection technologies. In the instance where an airport 
wants to perform ADF collection with a technology other than those 
described in the regulations, under proposed Sec.  449.20(b)(2) the 
permit authority may consult with the permittee and specify, on a case-
by-case basis, an alternative ADF collection technology as the manner 
in which the permittee must demonstrate compliance with its capture 
requirement. Under this provision, the Director would also be able to 
specify alternate operating parameters for one of the technologies 
listed in the proposed rule, in consultation with the permittee. As 
part of the permit application, the permittee would be required to 
demonstrate, to the Permit authority's satisfaction, that the specified 
technology is designed to achieve the capture requirement as set forth 
in today's proposal. Again, the only reporting requirement for this 
scenario would be for the permitted facilities to certify to their 
permit authorities that they are operating and maintaining their 
permitted technology as required.
    A third procedure, under proposed Sec.  449.20(b)(3), would be for 
the permitted facility to periodically monitor, through a mass balance 
analysis or other means deemed acceptable by the permitting authority. 
The permittee would report, at a frequency determined by the permit 
authority, the amount of ADF sprayed and the amount of available ADF 
collected, in order to determine the percentage of available ADF 
collected.
b. Ammonia Limits
    While EPA proposed a non-urea-based airfield deicing certification 
requirement, it is also proposing that an airport may choose a 
compliance alternative in which it would monitor all runway outfalls to 
demonstrate compliance with a proposed alternative compliance ammonia 
limit. However, as described further in Section VII.E.3, EPA 
anticipates that most if not all permittees would certify rather than 
choose the proposed compliance alternative ammonia limitation.

VIII. Economic Analysis for Airports

A. Introduction

    EPA's economic analysis assesses the costs and impacts of the 
proposed effluent guidelines on the regulated industry. This section 
explains EPA's methodology and the results of its economic analysis. 
The EA contains more detailed results of this analysis.

B. Economic Data Collection Activities

    EPA obtained the following data submitted by airlines to the Bureau 
of Transportation Statistics (BTS):
     Aircraft departures, enplaned passengers, and cargo by 
airport of origination, destination, airline, aircraft, and service 
type (passenger or cargo only) maintained in the Form 41 Traffic 
Database;
     Air carrier summary traffic and capacity statistics such 
as available seat-miles, available ton-miles, revenue seat-miles, and 
revenue ton-miles maintained in the Form 41 Traffic Database;
     Operating revenues, profits, and net income for large 
certificated carriers maintained in the Form 41 Financial Database;
     Operating revenues, profits, and net income for small 
certificated and commuter air carriers submitted by airlines to the BTS 
and maintained in the Form 298c Financial Database. These financial 
data are confidential business information and cannot made public until 
three years after the reporting year. EPA obtained them through a 
special request to the BTS, and they will not be included in the 
rulemaking public docket.
    EPA obtained data on airport revenues, expenses and other financial 
information that were submitted under FAA's Financial Reporting Program 
by commercial service airports receiving Airport Improvement Program 
(AIP) grants. As noted in Section VI above, EPA surveyed: All U.S. 
primary airports with more than 30,000 annual departures by commercial 
air carriers; a sample of small hub and non-hub primary airports with 
fewer than 30,000 commercial air carrier annual departures (excluding 
Alaska); and selected General Aviation/Cargo airports and Alaskan 
airports. The Airport Questionnaire collected data on airport 
ownership, financial management, signatory airlines, sources of capital 
funding, and non-airline aircraft operations. These data were collected 
to provide EPA with a context to understand better the data that were 
obtained through the Financial Reporting Program.
    In addition, EPA surveyed a sample of airlines that operated at 
each of the surveyed airports; all airlines with more than 20,000 
annual departures at a surveyed airport received a questionnaire, as 
well as a sample of airlines with more than 1,000 annual departures at 
each surveyed airport. The Airline Questionnaire collected data on 
deicing operations at each airport, including the airline's deicing 
budget, costs included in the budget, whether the airport is an 
operational hub for the airline, and whether its aircraft were deiced 
by another airline or a fixed base operator providing ground services 
at that airport.
    EPA also used journal articles, academic publications, and data and 
reports from trade organizations, FAA, DOT, and other government 
agencies and other publications to inform the analysis of the effluent 
guidelines.

C. Annualized Compliance Cost Estimates

    EPA estimates that 218 primary airports that perform deicing 
operations and have more than 1,000 annual jet departures will be 
regulated by the proposed rule. EPA estimated the economic cost to each 
potentially affected airport of complying with the BAT limitations 
being proposed today using the BAT technologies identified by EPA in 
this proposal. Thus, EPA assumed that airports would:
     Discontinue urea usage for airfield deicing and use 
substitute deicing products instead;
     Collect at least 60 percent of applied ADF and treat to 
the specified numeric discharge limit using anaerobic fluidized bed 
technology if the airport

[[Page 44702]]

has more than 10,000 annual departures, and on average 460,000 or more 
gallons of ADF is applied annually at the airport;
     Collect at least 20 percent of applied ADF and treat to 
the specified numeric discharge limit using anaerobic fluidized bed 
technology if the airport has more than 10,000 annual departures, and 
on average less than 460,000 gallons of ADF is applied annually at the 
airport.

Because many airports do not meet the above criteria, EPA estimates 
that approximately 164 primary airports, 135 non-primary airports, and 
almost 3,000 general aviation airports are not regulated under the 
proposed rule.
    EPA projects that 70 of the 218 in-scope airports would incur costs 
under this proposal associated with deicing of aircraft. EPA's 
assessment of the remaining 148 airports indicates they are already in 
compliance with the performance standard, and therefore would not incur 
additional costs because of this proposal. The technologies that are 
the basis for today's proposal are projected to cost affected airports 
$714.0 million in total capital costs over the 20-year analytic period. 
EPA believes the effective service life of deicing pads is at least 20 
years, but the effective service life of GRV and plug-and-pump 
technologies is 10 years. (Plug-and-pump technologies are not part of 
the proposed option.) Therefore, for any airport modeled using GRV and/
or plug-and-pump technologies, EPA incorporated capital expenditures in 
year 10 for replacement in addition to the initial capital expenditure. 
The total capital cost figure in Table VIII-1 includes all initial and 
replacement capital expenditures. However, because the replacement 
capital expenditures occur 10 years after promulgation, the discounted 
present value (PV) of those expenditures is less than their current 
value. Thus, the PV of capital costs is also presented in Table VIII-1 
to allow a fair comparison between technologies requiring replacement 
with those only requiring initial investment over the 20-year analytic 
period. The PV of capital costs under the proposed option 3 is $701.7 
million over the 20-year analytic period.
    The annual cost of operating and maintaining the technologies 
identified as BAT for aircraft deicing for this proposed rule, which 
includes the cost of using potassium acetate instead of urea to deice 
airfield pavement, is estimated at $45.9 million. Adding this operation 
and maintenance cost to the $45.4 million in capital costs of 
installing deicing pads at the seven airports who are not currently 
meeting the 60 percent capture requirement, the rule would have a total 
annualized cost of $91.3 million ($2006). Of the 70 airports projected 
to incur costs under this proposed rule: 40 airports only incur costs 
associated with the urea ban, 17 airports only incur costs associated 
with the collection and treatment of ADF, and 13 airports incur costs 
associated with both the urea ban and ADF collection and treatment. 
Table VIII-1 presents projected costs for the proposed rule, as well as 
the other three options examined (see Section VII.D.3).

                  Table VIII-1--BAT Costs to Airports That Deice Aircraft and Airfield Pavement
                                       [2006 $ millions--218 airports] \a\
----------------------------------------------------------------------------------------------------------------
                                                                Present
                                      Airports      Total       value of    Annualized   Annual O&M     Total
              Option                 incurring     capital      capital      capital       costs      annualized
                                       costs        costs        costs        costs                     costs
----------------------------------------------------------------------------------------------------------------
1.................................           67       $311.4       $299.5        $19.2        $17.1        $36.4
2.................................           75        457.8        435.2         28.0         82.1        110.1
3 \b\.............................           70        714.0        701.7         45.4         45.9         91.3
4.................................          121        871.8        848.7         54.9         50.0        105.0
----------------------------------------------------------------------------------------------------------------
\a\ EPA used a discount rate of 5.25% as provided by the airport industry. See Section 5 of the Economic
  Analysis for further information.
\b\ Proposed option.

D. Economic Impact Methodologies

    EPA's analysis of the economic impacts of the proposed effluent 
guidelines and new source performance standards for airport deicing 
operations examined the impacts of the proposed regulations on the 
economic viability of airports and their customer airlines. We note 
that there are a number of distinguishing features of this industry 
that make the analysis here different from the type of more traditional 
analysis EPA would perform for a for-profit manufacturing industry.
    First, almost all potentially affected airports are publicly owned 
and operated by local, county, or state governments, or by quasi-
governmental authorities created to operate the airport. As 
governmental or quasi-governmental entities, airports 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 airline customers legally required to cover 
expenditures in excess of costs.
    Second, if compliance costs are passed through to airlines serving 
the affected airports, those airlines would likely determine economic 
achievability on a route and/or airport basis, as well as how that 
route/airport fits into the airline's entire route structure. Further, 
a decision to drop a route at one airport if the route is no longer 
financially viable may affect the financial viability of connecting 
routes associated with the same or different airports. However, airline 
cost and revenue data are only available at the airline level, not on a 
route-specific basis.
    Third, recent years have been financially difficult for the air 
transportation industry. In aggregate, airlines earned negative 
operating profit (operating revenues less operating expenses) from 2001 
through 2004, and negative net income from 2001 through 2005. A 
comparison of the expected compliance costs of this proposed regulation 
with industry profits is not a useful benchmark here (as it usually 
would be for evaluating the impacts of effluent guidelines on for-
profit industries in better financial condition) where many airlines 
are actually losing money prior to this proposal.
1. Cost Annualization
    The first step in projecting the economic and financial impacts of 
this proposed rule on airports is cost annualization. For each airport, 
EPA projected the capital and operating and maintenance costs of the 
technology basis for each ADF target removal percentage over 20 years, 
discounted future costs using an airport-specific opportunity cost of 
capital, and annualized those costs to represent 20 equal annual cost 
payments incurred by the airport. Based on their expected service 
lives, the capital cost estimates incorporate periodic replacement of

[[Page 44703]]

GRVs and plug-and pump-technologies. For the purposes of projecting 
capital costs, EPA expects both these technologies will require 
replacement after 10 years, while a deicing pad is expected to last 20 
years before requiring replacement. The method for projecting each 
airport's capital and operating costs is described in Section VII.I.
    EPA assumed airports will issue tax-exempt, fixed coupon rate 
serial General Airport Revenue Bonds (GARBs) to fund capital 
expenditures. EPA assumed airports will issue bonds equivalent to the 
net present value of capital costs plus 3 percent to account for bond 
issuance costs. Capital costs were annualized using each airport's 
nominal bond rate for its most recent GARB issue. This was converted to 
a real rate using an average annual inflation rate of 2.3 percent over 
the last 5 years. The average nominal discount rate for costed airports 
was 5.25 percent, which is equivalent to 2.87 percent after accounting 
for inflation. Costs were annualized over 20 years. Table VIII-1 
presents the total net present value and annualized value of capital 
costs as well as the operating and maintenance costs for each option.
2. Impacts
    Because airports are generally non-profit government or quasi-
government (e.g., port authorities) enterprise funds, the effect of an 
effluent guideline on airport income statements and balance sheets is 
not equivalent to the impact on income of a for-profit private-sector 
business. Therefore, EPA chose to examine the financial impacts of the 
proposed effluent guidelines using two measures. First, EPA compared 
airport revenues with annualized compliance costs. Second, because EPA 
expects many, if not all, airports will fund capital expenditures by 
issuing debt (GARBs), 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 (2000) recommends 
the ``revenue test'' as a measure for impacts of programs that directly 
affect government and not-for-profit entities. The revenue test 
compares the annualized compliance costs of the regulation with the 
revenues of the governmental entity. The guidance suggests evaluating 
the affordability of a regulatory option as follows:
     If annualized compliance costs are less than 1 percent of 
revenues, the option is generally considered affordable;
     If annualized compliance costs are greater than 1 percent, 
but less than 3 percent of revenues, the option may be considered 
affordable if only a few entities are affected and the majority incurs 
costs less than one percent of revenues;
     If annualized compliance costs are greater than 3 percent 
of revenues, the option is not generally considered affordable.
    EPA found that only one surveyed airport is privately owned, and 
because that airport is not a commercial service airport, it would not 
be within the scope of coverage of today's proposed rule. All other 
surveyed airports are owned by state, city or county governments, or by 
airport or multi-port authorities. Thus, use of the revenue test is 
appropriate to measure impacts to airports. EPA used operating revenues 
as reported on Form 127 of the FAA's Airport Financial Reporting 
Program as the denominator for the revenue test ratio, and annualized 
compliance costs for each option as described under Cost Annualization 
(see Section VIII.D.1) as the numerator for the ratio.
b. Debt Service Coverage Ratio
    When creating quasi-governmental agencies such as port authorities, 
the legislation that created the agency typically includes a lower 
limit on the authority's debt service coverage ratio (DSCR). Airports 
owned and operated directly by a state or local government might also 
have direct limits on airport debt (if the airport has authority 
independent of the city or county government to incur debt). The 
authority will be in default on all bond issues if its DSCR falls below 
the relevant benchmark. Review of Comprehensive Annual Financial 
Reports (CAFR) for affected airports shows that the ratio of net 
revenues to debt service for any given year cannot fall below 1.25.
    EPA assumed capital financing will occur through the issue of 
GARBs; this can only be done if the additional debt does not cause the 
issuer's DSCR to fall below the benchmark. Therefore, EPA estimated the 
post-regulatory DSCR for each airport incurring capital expenditures 
under the proposed rule.
    From the Airport Questionnaire responses, EPA collected each 
airport's current DSCR, and the net revenues and debt service used to 
calculate that ratio. For airports that belonged to multi-airport 
systems under the same ownership, DSCR was reported at the level of the 
entire system. Therefore, EPA aggregated compliance costs for all 
affected airports in the system, and performed a single calculation for 
the entire system. EPA calculated the post-regulatory DSCR in two ways: 
(1) Assuming costs are passed through to airlines in the form of higher 
landing fees, and (2) assuming no costs are passed through. Some 
evidence suggests airports do not pass through 100 percent of costs, at 
least in the short run, if there is concern an airline might withdraw 
service if the airport increases fees. This might occur if the airport 
has nearby competitors, or if airline finances are fragile. Therefore, 
EPA wanted to determine if an airport would be in danger of default on 
its debt even if it was unable to pass through compliance costs to its 
airline customers.
    Assuming 100 percent cost pass-through from airports to airlines, 
EPA estimated the post-regulatory DSCR by: (1) Adding the net increase 
in landing fees associated with compliance (that is, total annualized 
compliance costs less incremental annual deicing operating and 
maintenance costs) to pre-regulatory airport net revenues, and (2) 
adding the annualized value of capital compliance costs to the debt 
service figure. Assuming no cost pass-through from airports to 
airlines, EPA estimated the post-regulatory DSCR by: (1) Subtracting 
incremental annual deicing operating and maintenance costs from pre-
regulatory airport net revenues, and (2) adding the annualized value of 
capital compliance costs to the debt service figure.
3. Cost Pass-Through
    Historically, most or all airport costs are eventually paid for by 
airlines and the airlines' customers. Airlines paid airports for 
operating costs through rates and charges, and for airport capital 
expansion through aviation user taxes that formed the basis for AIP 
grants or by providing the revenue stream to finance bond issues. In 
recent years, airports have developed new revenue streams from 
concessions, parking, and car rentals. In addition, much capital 
expenditure is now funded through Passenger Facility Charges (PFCs), 
although airlines view PFCs as similar to other fees that affect ticket 
prices, and thus reflect costs passed through to them and their 
passengers. Although these recent trends have modified airport finance, 
EPA's overall understanding is still that in the long run, a large 
percentage of airport costs are passed through to airlines and airline 
passengers in the form of increased fees.
    However, in the short run, cost pass-through (CPT) from airports to 
airlines might be significantly smaller than 100 percent. For example, 
due to the severe financial distress experienced by

[[Page 44704]]

airlines in the wake of 9/11, a Department of Transportation report 
showed that airports suspended or reduced airline rates and charges, 
contributed discretionary cash flow to reduce airline charges, and 
found other means of reducing (or at least refrained from increasing) 
airport costs to airlines. In addition, airports compete among 
themselves for airline service. Anecdotally, some airports in 
relatively close proximity to other significant airports have indicated 
to EPA that they are reluctant to increase airline rates and charges 
for fear of losing traffic to competitors.
    Although the general economic pressures that affect an airport's 
ability to pass through costs are well understood, EPA found no studies 
that have attempted to quantify this relationship. Therefore, to study 
the range of possible impacts, EPA has chosen to model CPT in the form 
of three scenarios: the two endpoints of the spectrum (0 percent and 
100 percent CPT), and an intermediate scenario of 50 percent CPT.
    In addition, airlines pass through costs to passengers in the form 
of higher ticket prices. The ability of airlines to do this depends 
largely on market-specific factors such as the desirability of an 
airport as a final destination, whether the trip to that final 
destination is for business or pleasure, and whether other airports 
with acceptable standards of airline service are close to that 
destination. If an airport serves a highly desirable final destination, 
with a high percentage of business travel, and no alternative airports 
nearby, airlines might be able to pass through significant costs to 
their passengers. However, although studies have measured the intensity 
of demand for airline services in general, there are very few studies 
examining airport-specific demand factors.
    In addition, the ability of airlines to pass through costs to 
passengers also depends on the supply of air transportation services. 
In some respects, airline tickets have become something of a commodity, 
where passengers largely base their choice on ticket price. This acts 
to drive prices down to a similar low level. The results of this might 
be observed in the recent behavior of airlines. With airline fuel costs 
projected to increase by 50 to 70 percent in 2008, airlines have found 
it difficult to raise fares, at least in the short run. Announced fare 
increases by one airline have not been followed by others, forcing the 
airline raising its fares to return them to their initial level. While 
airlines have recently started charging or increasing fees for checked 
bags, phone reservations, and in-flight meals and snacks, these fees 
are expected to cover only a fraction of increased fuel costs. Thus, it 
appears that at least in the short run, it is difficult in today's 
business climate for airlines to pass through a significant percentage 
of costs to their passengers.

E. Selection, Costs and Impacts of BAT Options

    Table VIII-2 summarizes the projected annualized compliance costs 
and the number and percent of in-scope airports projected to incur 
compliance costs greater than 3 percent of operating revenues under 
each option analyzed by EPA.

                             Table VIII-2--Summary of Impacts Under Analyzed Options
----------------------------------------------------------------------------------------------------------------
                                                                                      In-scope airports with
                                                                                    projected compliance costs
                                                               Total annualized      exceeding 3% of operating
                           Option                              compliance costs          revenues \a\ \b\
                                                               (2006 $millions)  -------------------------------
                                                                                      Number          Percent
----------------------------------------------------------------------------------------------------------------
1...........................................................               $36.4               9             4.2
2...........................................................               110.1              20             9.2
3 \c\.......................................................                91.3              11             5.1
4...........................................................               105.0              58            26.6
----------------------------------------------------------------------------------------------------------------
\a\ Assuming zero percent cost pass-through.
\b\ Impacts were not projected for 3 airports under Options 1 through 3, and 5 airports under Option 4. All 5
  airports are owned by the Alaska Department of Transportation and Public Facilities. Impacts to these airports
  could not be projected because the airport owner does not maintain airport-specific revenue figures.
\c\ Proposed option.

    Under Option 2, airports are projected to incur the largest total 
annualized costs of all four options examined, yet projected removals 
of COD are less than under either Option 3 or Option 4 (see Section 13 
of the TDD). Because Option 2 costs more but would remove fewer pounds 
of pollutants than either Option 3 or Option 4, EPA eliminated Option 2 
as a candidate for selection as best available technology for this ELG.
    EPA also rejected Option 4 as a candidate for selection as BAT, 
because more than one-quarter of in-scope airports (i.e., 59 out of 218 
in-scope airports) are projected to incur costs exceeding 3 percent of 
operating revenue under this option. The difference between Option 3 
and Option 4 is that Option 4 would extend the 20 percent ADF capture 
and treatment rate requirement from primary commercial service airports 
with more than 10,000 annual departures to primary commercial service 
airports with more than 1,000 annual departures (see Table 4-1 in the 
EA). Extending the capture requirement would cause 51 small airports 
with relatively low operating revenues that were not projected to incur 
costs under Option 3 to incur compliance costs under Option 4. Forty-
seven of these 51 airports are projected to incur costs exceeding 3 
percent of revenues (see Table 5-5 in the EA), which means that these 
entities would experience a heavy economic burden if required to meet 
this option, as described above. Based on the large number of airports 
that EPA projects would experience this heavy economic burden, EPA 
determined that Option 4 is not economically achievable.
    Under Option 3, the proposed regulations would require the 14 
airports where average ADF usage has been estimated to exceed 460,000 
gallons annually to capture and treat 60 percent of ADF. Airports with 
greater than 10,000 annual departures but less than 460,000 gallons of 
ADF usage would be required to meet a 20 percent ADF capture and 
treatment rate. Under Option 1, the regulations would require all 
airports with greater than 10,000 annual departures to meet the 20 
percent ADF capture and treatment rate. Thus, the difference between 
Option 1 and Option 3 in projected compliance costs, economic impacts, 
and pollutant

[[Page 44705]]

removals is entirely attributable to the stricter standard for the 14 
airports with the largest ADF usage; this stricter standard would add a 
projected $54.9 million in annualized compliance costs to the rule.
    EPA determined that both options are economically achievable. The 9 
airports projected to incur costs exceeding 3 percent of operating 
revenues under Option 1 would incur identical impacts under Option 3. 
Due to the 60 percent ADF capture and treatment standard, two 
additional airports are projected to incur costs exceeding 3 percent of 
operating revenues under Option 3 (see Table 5-5 in the EA). However, 
as discussed in Section 2.6 of the EA, very large airports such as 
these have significantly better access to financial resources than 
smaller airports and serve more passengers and aircraft. Thus, they are 
less vulnerable to a potential loss of service in response to increased 
rates and charges and earn higher revenue flows. Consequently, EPA 
believes these airports will be less affected than smaller airports by 
compliance costs that comprise a similar percentage of revenues. In 
addition, both of these airports are currently undergoing significant 
capital expansion and improvement programs; as part of these programs 
both airports are installing deicing pads, however EPA's costing 
assumed no deicing pads. Although EPA does not have sufficient 
information to determine if these pads will enable the airports to meet 
the 60 percent capture and treatment target without further capital 
expenditure, their installation should decrease the incremental costs 
necessary to reach that standard relative to those estimated for our 
analysis.
    Airports with less than 10,000 total annual departures have been 
excluded from ADF collection and treatment requirements based on 
possible economic achievability concerns. EPA's analysis shows that 
approximately 46 percent of the next approximately 100 airports (in 
terms of ADF usage) would incur costs of greater than 3 percent of 
their revenue if required to comply with these additional requirements. 
Moreover, airports with less than 10,000 annual departures are smaller 
airports and may have greater difficulty raising funds to meet these 
ADF requirements. For these reasons, we have decided to exclude 
airports with less than 10,000 total annual departures from the ADF 
collection and treatment requirements of this proposed rule.
    As a check on whether Option 3 is the best combination of 
technologies to be selected as BAT, EPA also examined whether there 
might be an additional option that would result in more removals than 
Option 3 (but less than Option 4) while still being economically 
achievable. Option 3 would impose a 60 percent capture requirement on 
the 14 airports that are the largest by ADF usage. EPA therefore 
considered whether the 60 percent requirement could be extended to 
additional airports beyond the top 14 (i.e., extended to airports with 
somewhat less ADF usage) without going beyond the limits of economic 
achievability. EPA reviewed the projected costs of installing deicing 
pads at airports with less than 460,000 gallons of annual ADF usage as 
well as those airports' operating revenues. From this review, EPA 
concluded that the set of airports immediately following the ``top 14'' 
by ADF usage would incur significantly greater economic impacts 
relative to their resources than would the top 14 airports. 
Specifically, of those airports that would incur costs under today's 
proposal, 5 of the first 6 airports that immediately follow the top 14 
by ADF usage would be projected to incur costs greater than 3 percent 
of revenues and therefore would incur a heavy economic burden. In 
addition, 29 of the 57 airports in all that follow the top 14 by ADF 
usage would be projected to incur costs over 3 percent of revenues. 
This confirms, in EPA's view, that imposing the 60 percent requirement 
on only the top 14 airports under Option 3 is the appropriate cutoff 
point for determining economic achievability for this industry. 
Moreover, these additional airports, if subjected to a 60 percent 
capture requirement, would be expected to achieve few additional pounds 
of pollutant removals relative to Option 3. This additional analysis 
confirms EPA's proposal to identify the Option 3 technologies as the 
BAT basis for this effluent limitation guideline. See ``Regulatory 
Option Development for the Airport Deicing Operations Rulemaking 
Proposal'' (DCN AD01168) in the docket for additional information.
    Tables VIII-3 through VIII-5 below present more detailed estimated 
costs and impacts of the options that EPA considered for BAT.
    Table VIII-3 presents the results of the revenue test for affected 
airports. Under Option 3, 174 of 218 in-scope airports (80 percent) are 
projected to incur zero annualized compliance costs or annualized 
compliance costs composing less than 1 percent of revenues. Of the 
remainder, 11 (5 percent) are projected to incur costs exceeding 3 
percent of revenues, and 29 (13 percent) are projected to incur costs 
exceeding 1 percent, but less than 3 percent of revenues.

                      Table VIII-3--Financial Impacts of BAT Options on Airports That Deice
                                         [2006 $ millions--218 airports]
----------------------------------------------------------------------------------------------------------------
                                                                  Number of airports with ratio of annualized
                                                                compliance costs to operating revenues of: \a\
                                                    Total    ---------------------------------------------------
                     Option                       annualized                                             Not
                                                    costs      Less than    Between 1%    Greater      analyzed
                                                                   1%         and 3%      than 3%        \b\
----------------------------------------------------------------------------------------------------------------
1..............................................        $36.4          178           27            9            3
2..............................................        110.1          165           30           20            3
3 \c\..........................................         91.3          174           29           11            3
4..............................................        105.0          130           25           58            5
----------------------------------------------------------------------------------------------------------------
\a\ Number of airports may not sum to 218 due to rounding.
\b\ Airports incurred compliance costs but financial impacts could not be analyzed due to lack of airport
  revenue data.
\c\ Proposed option.

    Tables VIII-4 and VIII-5 present the projected impact of the rule 
on the ability of the airports to finance their debt. To complete this 
analysis, EPA first had to distinguish multiple airport owners from 
single airport owners. Multiple airport owners might incur costs for 
several airports, and debt is typically held at the ownership level, 
not at the level of the individual airports. EPA used question B-4 of 
the Airport Deicing Questionnaire to

[[Page 44706]]

identify all multiple airport owners, and how many airports under that 
ownership received a survey.
    EPA found 10 airport owners received surveys for 31 airports; of 
these, 9 airport owners received surveys for 21 airports that were 
determined to be in-scope of the proposed regulation. All results for 
multiple airport owners are presented unweighted because each airport 
was individually identified and therefore does not represent any other 
airports but itself with respect to ownership. EPA aggregated projected 
costs for all in-scope airports under that ownership pattern and 
analyzed them using the owning organization's debt service coverage 
ratio obtained from the Comprehensive Annual Financial Report. The 
remaining 93 (unweighted) in-scope airports were evaluated individually 
as single-owner airports. Although EPA did not stratify the survey 
based on ownership, and therefore the survey weights cannot be 
considered statistically reliable for determining the count of single-
owner airports, the weights generally reflect the relative frequency of 
single airport ownership. EPA presents both the weighted and unweighted 
results for this group of airports.
    Some airports did not provide sufficient data to analyze impacts on 
the DSCR. This could occur because: (1) The airport does not use debt 
to finance capital projects, (2) data were not provided through the 
survey or the airport's annual financial report, or (3) data are 
available but the pre-regulatory DSCR is less than 1.25. For single-
owner airports, the impact on DSCR could be projected for all airports 
expected to incur capital costs under the proposed option. Among multi-
airport owners, the impact on DSCR could be projected for all except 
one airport owner that was expected to incur capital costs for three 
airports under the proposed option. This airport owner is described in 
greater detail below.
    Table VIII-4 presents the projected impact of the rule on the 
ability of single airport owners to finance their debt. Assuming no 
costs are passed through to their air carrier customers, two airports 
are projected to incur costs under the proposed rule that would result 
in their post-regulatory debt service ratio falling below the threshold 
that indicates default. However, one of these airports installed a 
deicing pad after the survey was submitted, and therefore would incur 
lower compliance costs than projected here. Under the proposed rule, no 
single airport owners are projected to be in danger of default when 100 
percent of compliance costs are assumed to be passed through to airline 
customers.

   Table VIII-4--Impact of Financing BAT Options on Airport Debt Service Coverage Ratio--Single Airport Owners
                                                 [192 airports]
----------------------------------------------------------------------------------------------------------------
                                                                                Owners with pre-regulatory DSCR
                                                                              >1.25 & post regulatory DSCR <1.25
                 Option                      Incur costs    Not analyzed \a\ -----------------------------------
                                                                                  100% CPT           0% CPT
----------------------------------------------------------------------------------------------------------------
1.......................................                54                 6                 0                 3
2.......................................                62                 6                 1                 7
3 \b\...................................                55                 6                 0                 3
4.......................................                99                42                 0                 3
----------------------------------------------------------------------------------------------------------------
\a\ Of the 218 airports (weighted), 192 were estimated to be both in-scope, and the only airport controlled by
  its ownership. These columns represent the number of those 192 airports projected to incur costs under each
  option, and of those airports incurring costs, the number that cannot be analyzed due to lack of sufficient
  data.
\b\ Proposed option.

    Table VIII-5 presents the projected impact of the rule on the 
ability of the owner to finance debt for the 6 multi-airport systems 
that own the 13 airports projected to incur costs under the proposed 
rule. For the 5 airport systems owning the 10 airports projected to 
incur costs for which the DSCR analysis could be performed, none of the 
four options considered for the proposed rule are projected to have an 
impact on the ability of airport authorities to finance debt.
    EPA could not analyze one multi-airport system, which is 
responsible for five airports projected to incur costs under at least 
one option. This is the Rural Aviation System of the Alaska Department 
of Transportation and Public Facilities, which owns 256 rural airports. 
EPA projects that three of those airports would be affected by the 
proposed rule. The Alaska Rural Aviation system does not use debt 
financing; therefore, it has no DSCR to analyze. Instead, it relies on 
state and federal grants to fund capital expenditures.

                       Table VIII-5--Impact of Financing BAT Options on Airport Debt Service Coverage Ratio--Multi Airport Owners
                                                 [9 airport authorities owning 21 in-scope airports] \a\
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                  Incur costs \b\                Not analyzed \b\           Owners with pre-regulatory
                                                         ----------------------------------------------------------------  DSCR >1.25 & post regulatory
                         Option                                                                                                     DSCR <1.25
                                                              Owners         Airports         Owners         Airports    -------------------------------
                                                                                                                             100% CPT         0% CPT
--------------------------------------------------------------------------------------------------------------------------------------------------------
1.......................................................               5              11               1               3               0               0
2.......................................................               5              11               1               3               0               0
3 \c\...................................................               6              13               1               3               0               0

[[Page 44707]]

4.......................................................               6              16               1               5               0               0
--------------------------------------------------------------------------------------------------------------------------------------------------------
\a\ Because these airports and their ownership were individually identified, the results cannot be assumed to represent any airport owners other than
  themselves. Therefore, these results are not weighted.
\b\ Of 114 surveyed airports (unweighted), 21 (unweighted) under the control of 9 distinct ownership authorities were determined to be in-scope of the
  proposed rule. These columns represent the number of those airports and the number of airport ownership authorities projected to incur costs under
  each option, and of those airports incurring costs, the number that cannot be analyzed due to lack of sufficient data.
\c\ Proposed option.

    In light of the foregoing analysis, EPA does not believe that the 
projected impacts of the rule on the ability of airports to finance 
their debt are significant enough to change our proposed findings on 
which BAT options are economically achievable.

F. Economic Impacts for New Sources

    As explained in Section VII.F above, EPA has determined that the 
proposed NSPS would not impose a barrier to entry, in both the new 
runway and new airport scenarios. The costs for a centralized deicing 
pad are estimated at ten percent or less of the total cost for a new 
runway, and this proportion is even smaller when compared to the cost 
of building a new airport. An analysis of these costs is contained in 
the record for today's proposal.

G. Cost and Pollutant Reduction Comparisons

    EPA compared the projected compliance costs for the proposed rule 
with the estimated reduction in pollutants resulting from the effluent 
guidelines. Table VIII-6 presents projected compliance costs and 
estimated pounds of COD and ammonia removed from airport stormwater 
under the proposed rule. Option 3 is expected to reduce COD and ammonia 
loads by 45.2 million pounds at an annualized cost of $91.3 million, 
for a cost of $2.02 per pound of pollutant removed.

      Table VIII-6--Pollutant Removals, Costs and Cost-Effectiveness of BAT Options for Airports That Deice
----------------------------------------------------------------------------------------------------------------
                                                                       Total           Total
                                                                     pollutant      annualized        Cost/lb
                             Option                                  removals      costs (2006 $     pollutant
                                                                   (million lb)        mil.)          removed
----------------------------------------------------------------------------------------------------------------
1...............................................................            26.6           $36.4           $1.37
2...............................................................            36.6           110.1            3.01
3 \a\...........................................................            45.2            91.3            2.02
4...............................................................            47.4           105.0            2.22
----------------------------------------------------------------------------------------------------------------
\a\ Proposed 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 proposal is similar or less expensive than many 
guidelines promulgated to date including: Aluminum Forming, $2.42/Lb; 
Landfills, $15.00/Lb and; Waste Combustors, $38.83/Lb.

H. Small Business Analysis

    The Regulatory Flexibility Act (RFA), as amended by the Small 
Business Regulatory Enforcement Fairness Act of 1996 (SBREFA; 
hereinafter referred to as RFA), acknowledges that small entities have 
limited resources, and makes it the responsibility of regulating 
federal agencies to avoid burdening such entities unnecessarily. The 
ultimate goal of RFA is to ensure that small entities do not incur 
disproportionate adverse economic impacts 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 of small entities: small 
business, small not-for-profit organization, and small governmental 
jurisdictions. To determine airport ownership, EPA examined FAA Airport 
Data (Form 5010) and the Contact Information data file for National 
Flight Data Center (NFDC) facilities, which list the owner of each 
airport. EPA matched all 153 surveyed airports (representing 359 
airports, both in-scope and out-of-scope) to their owners and 
determined that with the exception of one privately owned airport, 
ownership 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 governmental 
legislation to maintain and operate airports, shipping ports, and other 
government-owned facilities 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 entity with its population, EPA estimates 
that:
     16 surveyed airports representing 76 airports are owned by 
small government entities
     8 surveyed airports representing 34 airports owned by 
small government entities are in the scope of the proposed rule.

Although many Alaskan airports are relatively small when measured by 
service level, most of these airports are owned by the State of Alaska 
and therefore are not considered small for

[[Page 44708]]

the purposes of the RFA; 10 of the 11 surveyed Alaskan airports are not 
small by this standard.
    EPA projected impacts on these small government entities that own 
airports using the revenue test described in Section VIII.D.2. EPA 
found that 3 of the 34 in-scope airports owned by small government 
entities are expected to incur annualized compliance costs exceeding 
three percent of airport operating revenues. These results are 
presented in Table VIII-7.

               Table VIII-7--Financial Impacts of BPT/BAT Options on Small Airports That Deice \a\
                                         [2006 $ millions--34 airports]
----------------------------------------------------------------------------------------------------------------
                                                   Number of airports with ratio of annualized compliance costs
                                       Total                         to operating revenues of:
             Option                 annualized   ---------------------------------------------------------------
                                       costs                      Between 1% and   Greater than    Not analyzed
                                                   Less than 1%         3%              3%              \b\
----------------------------------------------------------------------------------------------------------------
1...............................            $1.8              23               8               3               0
2...............................             4.8              23               8               3               0
3 \c\...........................             1.8              23               8               3               0
4...............................             3.0              23               0              11               0
----------------------------------------------------------------------------------------------------------------
\a\ An airport is considered small if the governmental entity that owns the airport serves a region with less
  than 50,000 people.
\b\ Airports incurred compliance costs but financial impacts could not be analyzed due to lack of airport
  revenue data.
\c\ Proposed option.

    As privately owned, for-profit businesses, air carriers are subject 
to the small business definitions set forth by the Small Business 
Administration's size standards. For EPA's purposes, the size standards 
for the North American Industrial Classification System (NAICS) 
Scheduled Passenger and Freight Air Transportation (NAICS 481111 and 
481112) sectors are appropriate for determining potentially affected 
small airlines. Thus, air carriers with fewer than 1,500 employees will 
be considered small for the purposes of this analysis.
    Available employment data for air carriers are provided by the BTS 
in their Employment Statistics--Certificated Carriers report. This data 
set does not contain records for all affected air carriers. For some 
air carriers with missing data, EPA obtained employment figures from 
annual reports or the annual report of the Regional Airline 
Association. For the remaining carriers, EPA compared their departure 
and enplanement data to the same data for air carriers with employment 
data. EPA determined that annual departures could be used as a suitable 
proxy for size. Using BTS T-100 data, EPA found 139 U.S. air carriers 
had at least one departure from an in-scope airport in 2006. Based on 
employment, or annual departures for air carriers without employment 
data, EPA estimates that of these 139 U.S. air carriers operating from 
in-scope airports in 2006, 36 are not small (27.5 percent) and 103 
(72.5 percent) are small business owned.

IX. Airline Impacts

    The economic and operational structure of airport deicing differs 
significantly from most industries for which EPA has promulgated 
effluent limitations and guidelines. For most industries, EPA evaluates 
direct impacts to affected entities, and only secondarily considers 
impacts on those entities' suppliers and customers. In the case of 
airport deicing, the airport is typically the holder of the NPDES 
permit and thus responsible for collection and treatment of ADF-
contaminated stormwater; air carriers that use the airport are 
occasionally co-permittees, but never the principal permittee at the 
airport. However, the air carrier (or a contractor to the air carrier 
such as another airline or an FBO) is the entity that uses the ADF at 
the airport under rigorous safety guidelines set by the FAA. 
Furthermore, in the long run, air carriers (and their passengers) pay 
for much of the airport's infrastructure and operating expenses. 
Therefore, EPA has chosen to evaluate these secondary impacts of the 
proposed regulation on air carriers in addition to airports.
    EPA examined impacts to airlines with compliance costs passed 
through from airports in the form of higher landing fees. EPA compared 
compliance costs with airline operating revenues (``sales test''); this 
test was supplemented with a comparison of compliance costs with 
operating profit and net income for those airlines with positive 
earnings. EPA also analyzed the impact of costs relative to common air 
carrier benchmarks for unit measures of cost and capacity such as cost 
per available seat-mile. EPA examined impacts of the preferred option 
on airline operating revenue between 2004 and 2006. Only in 2005, and 
for only one airline out of roughly 120 during that period were 
compliance costs greater than three percent of operating revenue. EPA 
does not believe that these impacts are significant enough to change 
our findings on which BAT options are economically achievable. For a 
more detailed discussion of these impacts, see Sections 3.3 and 5.3, 
respectively, of the EA.

X. Environmental Assessment

A. Environmental Impacts

    EPA has evaluated environmental impacts associated with the 
discharge of wastewater from airport deicing activities (Environmental 
Impact and Benefit Assessment for Proposed Effluent Guidelines and 
Standards for the Airport Deicing Category (EIB)). As discussed in 
Section VII.E, deicing wastewater discharges can increase 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 BOD5. 
All primary ingredients in both aircraft and airfield deicers exert 
oxygen demand. Propylene glycol and ethylene glycol are the primary 
ingredients in aircraft deicers. Acetate salts, formate salts, 
propylene glycol, ethylene glycol and urea are the primary ingredients 
in airfield deicers. Propylene glycol and ethylene glycol, in 
particular, exert extremely high levels of oxygen demand when they 
decay in the environment. Acetates, formates, and urea exert lower, 
though still significant, levels of oxygen demand.
    Acetate or formate salts, the primary ingredients 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 primary airfield deicer ingredient, decomposes in 
water to produce ammonia, a toxic compound, and nitrates, a nutrient 
pollutant that can increase the

[[Page 44709]]

incidence of organism blooms in surface waters.
    Aircraft and airfield deicers also contain additives in addition to 
the primary ingredients. These additives serve a variety of purposes 
such as reducing fluid surface tension, thickening, and fire and 
corrosion inhibition. Because deicer manufacturers consider 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 information through various 
public sources, and identified several additives with toxic properties. 
These include nonylphenol ethoxylates, alcohol ethoxylates, triazoles, 
and polyacrylic acid. Because deicer formulations change periodically, 
some of the additives EPA identified may not be present in current 
formulations. Nevertheless, the properties of the additives EPA 
identified may be indicative of deicer additive properties in general. 
EPA solicits additional information on the identity of deicer 
ingredients, and on the quantities in which they are used in current 
formulations. EPA also solicits information about potential 
environmental impacts associated with ingredients in deicer 
formulations.
    Airports in the United States discharge deicing wastewater to a 
wide variety of waterbody types including streams, rivers, lakes and 
estuaries. Many airports discharge deicing wastewater to small streams 
with limited waste dilution and assimilation capacities. Impacts from 
deicing wastewater discharges have been documented in a variety of 
surface waters adjacent to or downstream of a number of airports in the 
United States. Some locations experienced acute impact events, whereas 
other locations have chronically degraded conditions. Observed impacts 
to surface waters include both physical and biological impacts. Some 
surface waters have been listed as impaired under section 303(d) of the 
CWA because they do not meet applicable state water quality standards. 
Physical impacts include elevated levels of glycol, salinity, ammonia, 
and other pollutants; depressed oxygen levels; foaming; noxious odors; 
and discoloration. Biological impacts include reduced organism 
abundance; fish kills; modified community composition; and reduced 
species diversity.
    Deicing wastewater discharges have impaired both aquatic community 
health and human uses of water resources. Available documentation 
indicates multiple cases of hypoxic conditions and severe reduction in 
aquatic organism levels 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 associated with regulatory 
proposals to reduce the discharge of pollutants from airport deicing 
activities. This assessment is described in detail in the EIB. The 
proposed BAT requirement would decrease COD discharges associated with 
airport deicing activities by approximately 39.9 million pounds per 
year. The proposed BAT requirement would also reduce ammonia discharges 
by 4.7 million pounds. The proposed rule would also reduce loadings of 
additives in aircraft deicer formulations to the environment.
    EPA estimates that a reduction in pollutant loadings will take 
place at approximately 70 airports around the country. 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 deicing pollutant 
loadings. Documented improvements have included abatement of noxious 
odors, decline in fish kill frequency, and partial recovery of 
community species diversity, and organism abundance in small water 
bodies.
    Today's proposed rule would decrease pollutant loadings to multiple 
surface waters currently listed as impaired under sec. 303(d). The 
proposal will also reduce pollutant loadings to surface drinking water 
intakes, parks, and residential areas downstream of airports. 
Groundwater aquifers will also benefit. See the EIB for additional 
details.

XI. Non-Water Quality Environmental Impacts

    Sections 304(b) and 306 of the Clean Water Act require EPA to 
consider non-water-quality environmental impacts (including energy 
requirements) associated with effluent limitations guidelines and 
standards. To comply with these requirements, EPA considered the 
potential impact of the collection and treatment technologies on energy 
consumption, air emissions, and solid waste generation. EPA prepared 
these analyses only for technologies associated with the BAT and NSPS 
requirements.

A. Energy Requirements

    Net energy consumption considers electrical requirements for 
pumping collected fluid from centralized deicing pads, and electrical 
requirements for operating the anaerobic fluidized bed (AFB) 
bioreactors and the aerated ponds and fuel requirements for glycol 
recovery vehicles (GRVs). Detailed calculations regarding net energy 
consumption for the collection and treatment technologies are provided 
in a separate memorandum entitled ``Energy Requirements for ADF 
Contaminated Stormwater Collection and Treatment Alternatives'' (DCN 
AD011167), available in the public record for this rule.
    To estimate incremental electrical requirements associated with 
pumping collected ADF to either tanks or ponds, EPA assumed airports 
would continuously operate three 40-horsepower (hp) electric motors 
during each deicing day. EPA also conservatively assumed that all 
airports would use pumps rather than allow ADF-impacted stormwater to 
flow by gravity to holding tanks or ponds. Using that assumption, EPA 
estimated the total incremental electrical usage associated with the 
proposed rule would be approximately 1.2 million kilowatt hours per 
year (kWh/yr).
    EPA developed another relationship between electrical use and 
chemical oxygen demand (COD) removal by the AFB bioreactors based on 
information provided by Albany International Airport. Using the 
information from Albany Airport, EPA estimated the electrical 
requirement for COD removal and used that rate to estimate electrical 
usage associated with COD removal.
    The AFB treatment systems also generate biogas that can be used as 
a source of heat when burned in facility boilers or when converted to 
electricity using technologies such as microturbines or fuel cells. To 
estimate the potential electricity that could be generated if all AFB 
treatment systems installed microturbines to generate electricity, EPA 
developed a relationship between biogas generation and COD removal 
based on data provided by Albany Airport. EPA used these data to 
determine the potential energy of the associated biogas.
    The comparison of the potential electrical generation from 
converting biogas to electricity to the electrical requirements for AFB 
operation

[[Page 44710]]

indicates that treatment of ADF-contaminated stormwater could generate 
nearly the same amount of electricity that is needed to operate the 
treatment systems. Based on this analysis, there will not be a net 
increase in electricity to operate the collection and treatment systems 
for ADF-contaminated stormwater.
    EPA also analyzed fuel use by GRVs collecting ADF-contaminated 
stormwater. EPA used Airport Questionnaire data for diesel fuel costs 
for GRVs, and then estimated an average diesel fuel use based on the 
unit cost for diesel fuel of $2.07/gal.\1\ EPA then estimated annual 
fuel usage per gallon of applied ADF to be 0.08 gal/gal ADF applied. 
Using this relationship, EPA estimated total incremental No. 2 diesel 
fuel consumption at all in-scope airports installing additional 
collection equipment to be 604,000 gallons per year.
---------------------------------------------------------------------------

    \1\ This diesel fuel price was the average reported by the 
Energy Information Administration for the 2004-05 winter season, the 
same period that EPA is analyzing for airport deicing activity.
---------------------------------------------------------------------------

    EPA compared incremental diesel fuel use by GRVs at all airports 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 proposed rule is less 
than 0.005 percent of the annual amount of diesel fuel consumed.

B. Air Emissions

    Additional air emissions as a result of the proposed rule could be 
attributed to added diesel fuel combustion by GRVs collecting ADF-
contaminated stormwater, from additional jet engine taxi time related 
to deicing pads, and from anaerobic treatment of ADF. Emissions from 
these sources are discussed below.
1. Emissions From GRV Collection
    As discussed in Section XI.A above, EPA conservatively estimated 
that GRVs collecting ADF-contaminated stormwater at airports will 
consume an additional 604,000 gallons per year of No. 2 diesel fuel. To 
estimate air emissions related to combustion of No. 2 diesel fuel in 
the internal combustion engines on GRVs, EPA used published emission 
factors for internal combustion engines. The Agency selected emission 
factors for gasoline and diesel industrial engines because EPA assumed 
this class to be a more representative population of engines. To 
estimate emissions from the GRVs, EPA first converted the additional 
604,000 gallons of diesel fuel to million British Thermal Units (MMBtu) 
and then applied the appropriate emission factors. The calculated 
annual emissions indicate that an additional 4,781 tons per year of 
carbon dioxide (CO2) will be emitted from GRVs combusting 
additional diesel fuel to comply with the proposed rule. Carbon dioxide 
is the primary greenhouse gas attributed to climate change, and the 
6,900 additional tons per year that would be associated with the 
proposed rule is very small relative to other sources. For example, in 
2006, industrial facilities combusting fossil fuels emitted 948 million 
tons of CO2 equivalents. An additional 6,900 tons per year 
from GRVs is less than a 0.001 percent increase in the overall 
CO2 emissions from all industrial sources.
2. Emissions From Transportation to Aircraft Deicing Pads
    To estimate aircraft emissions associated with the additional time 
spent taxiing to and from newly installed deicing pad and idling during 
deicing, EPA used the seven busiest airports where deicing pads would 
likely be installed to comply with the proposed rule. To estimate 
aircraft emissions for each airport from transportation to newly 
installed deicing pads, input files such as departure information, 
types of aircraft being deiced, and deicing days were compiled and 
applied to the Emissions and Dispersion Modeling System (EDMS), an 
emission-estimating tool developed by the FAA for activities relative 
to airports. Typically, the EDMS input file quantifies aircraft 
activity relative to an aircraft's landing and takeoff (LTO) cycle. The 
cycle begins when the aircraft approaches the airport on its descent 
from cruising altitude, then lands and taxis to the gate, where it 
idles during passenger deplaning. The cycle continues as the aircraft 
idles during passenger boarding, taxis back out onto the runway, takes 
off, and ascends (climbout) to cruising altitude. Thus, the six 
specific operating modes in an LTO cycle are as follows:
     Approach;
     Taxi/idle-in;
     Taxi/idle-out;
     Idling;
     Takeoff; and
     Climbout.
    The LTO cycle provides a basis for calculating aircraft emissions. 
During each mode of operation, an aircraft engine operates at a 
specific power setting and fuel consumption rate for a given aircraft 
make and model. Emissions for one complete cycle are calculated using 
emission factors for each operating mode for each specific aircraft 
engine combined with the typical period of time the aircraft is in the 
operating mode.
    For this assessment, EPA ran the EDMS model using default time-in-
mode values for each component of the LTO cycle. Next, the Agency 
adjusted the time-in-mode values in the model to account for additional 
time spent traveling to the deicing pad (15 minutes), engine idling 
while deicing (30 minutes), and taxing away from the deicing pad (15 
minutes) and reran the model with these adjusted time-in-mode values. 
Then, EPA subtracted the baseline model run from the second model run 
to estimate the additional emissions associated with deicing.
    EPA then adjusted these values to reflect the snow or freezing 
precipitation (SOFP) days for each airport by multiplying the annual 
values by the SOFP days divided by 365 days per year.
    EPA also estimated total annual LTO aircraft emissions for the 
seven airports to compare aircraft emissions associated only with 
deicing. The calculations indicate that the proposed rule could 
increase carbon monoxide emissions from aircraft at the impacted 
airports by as much as 6.9 percent due to additional ground-time needed 
for pad deicing. Although the annual percentage increase in criteria 
pollutant emissions from the seven airports included in this analysis 
is a concern, the actual increase in emissions (e.g., 903 tons per year 
of carbon monoxide) is insignificant when compared to total criteria 
pollutant emissions for the aircraft sector. For example, in 2002, EPA 
estimated total carbon monoxide emissions from the aircraft sector at 
approximately 260,000 tons. The increase in criteria pollutant 
emissions resulting from additional aircraft deicing time account 
amounts to less than a 0.3 percentage increase in the aircraft sector 
annual criteria pollutant emissions.
3. Emissions From AFB Treatment Systems
    Anaerobic digestion of glycols found in ADF contaminated stormwater 
generates biogas containing approximately 60 percent 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 temperature. The remainder 
of gas can be either combusted in a microturbine for electricity 
generation or flared. Regardless of the combustion technology, nearly 
all biogas generated by AFBs is converted to carbon dioxide, the 
primary greenhouse gas. EPA calculates 17,300 additional tons per

[[Page 44711]]

year for 60% ADF capture, which is very small relative to other 
sources. For example, in 2006, industrial facilities combusting fossil 
fuels emitted 948 million tons of CO2 equivalents. An 
additional 17,300 tons per year of carbon dioxide from AFB treatment is 
less than 0.002 percent of the annual industrial carbon dioxide 
emissions nationwide.

C. Solid Waste Generation

    AFB bioreactors will generate sludge that will require disposal, 
likely 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 proposed collection and treatment scenarios and then 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 media) that may be 
entrained into the sludge. However, this method does provide an order 
of magnitude estimate of sludge generation that can be compared to 
other types of common biological treatment systems to determine if AFB 
sludge generation would be unusually high at airports treating ADF-
contaminated stormwater.
    To provide some perspective on the potential total amount of 
biomass produced annually by the AFB biological reactors treating ADF-
contaminated stormwater, EPA compared the most conservative biomass 
generation estimate with its national biosolids estimates for all 
domestic wastewater treatment plants throughout the United States. 
Approximately 8.2 million dry tons of biosolids will be produced in 
2010. EPA estimates that AFB bioreactors treating ADF-contaminated 
stormwater will increase biosolids generation in the United States by 
less than 0.01 percent.

XII. Regulatory Implementation

A. Relationship of ELGs to NPDES Permits

    Effluent guidelines act as a primary mechanism to control the 
discharge of pollutants to waters of the U.S. Once finalized, the 
regulations would be applied to airports through incorporation in 
individual or general NPDES permits issued by EPA or authorized states 
or tribes under section 402 of the Act.
    The Agency has developed the limitations for this proposed rule to 
cover the discharge of pollutants for this point source category. In 
specific cases, the NPDES permit authority may elect to establish 
technology-based permit limits for pollutants not covered by this 
regulation. In addition, if state water quality standards or other 
provisions of state or federal law require limits on pollutants not 
covered by this regulation (or require more stringent limits or 
standards on covered pollutants to achieve compliance), the permit 
authority must apply those effluent limitations or standards.
    For individual permits, ELG provisions are typically incorporated 
when those permits are renewed, although permit authorities may require 
modification upon promulgation.

B. Best Management Practices

    Sections 304(e), 308(a), 402(a), and 501(a) of the CWA authorize 
the Administrator to prescribe BMPs as part of effluent guidelines and 
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 section 
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, section 402(a)(2), read in concert with section 501(a), 
authorizes EPA to prescribe as wide a range of permit conditions as the 
Administrator deems appropriate in order to ensure compliance with 
applicable effluent limitations and standards and such other 
requirements as the Administrator deems appropriate.
    Dikes, curbs, and other control measures are being used at some 
airport facilities to contain leaks and spills as part of good 
``housekeeping'' practices. However, on a facility-by-facility basis a 
permit writer may choose to incorporate BMPs into the permit. See the 
TDD for this proposed rule for a detailed discussion of pollution 
prevention and best management practices used by airports.

C. 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 unintentional and temporary noncompliance 
with technology-based permit effluent limitations because of factors 
beyond the reasonable control of the permittee. EPA's regulations 
concerning bypasses and upsets for direct dischargers are set forth at 
40 CFR 122.41(m) and (n) and for indirect dischargers at 40 CFR 403.16 
and 403.17.

D. Variances and Modifications

    The CWA requires application of effluent limitations established 
pursuant to section 301 or pretreatment standards of section 307 to all 
direct and indirect dischargers. However, the statute provides for the 
modification of these national requirements in a limited number of 
circumstances. Moreover, the Agency has established administrative 
mechanisms to provide an opportunity for relief from the application of 
the national effluent limitations guidelines and pretreatment standards 
for categories of existing sources for 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 discharging facility is fundamentally 
different with respect to factors considered in establishing the 
limitation of standards applicable to the individual facility. Such a 
modification is known as a ``fundamentally different factors'' (FDF) 
variance. EPA, in its initial implementation of the effluent guidelines 
program, provided for the FDF modifications in regulations. These were 
variances from the BCT effluent limitations, BAT limitations for toxic 
and nonconventional pollutants and BPT limitations for conventional 
pollutants for direct dischargers. For indirect dischargers, EPA 
provided for FDF modifications from pretreatment standards. 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 Act of 1987, Congress added new 
sec. 301(n) of the Act. This provision explicitly authorizes 
modifications of the otherwise applicable BAT effluent limitations or 
categorical pretreatment standards for existing sources, if a facility 
is fundamentally different with respect to the factors specified in 
section 304 (other than costs) from those considered by EPA in 
establishing the effluent limitations or pretreatment

[[Page 44712]]

standard. Section 301(n) also defined the conditions under which EPA 
may establish alternative requirements. Under section 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 or standard must be 
no less stringent than justified by the difference and must not result 
in markedly more adverse non-water quality environmental impacts than 
the national limitation or standard.
    EPA regulations at 40 CFR Part 125, subpart D, authorizing the 
Regional Administrators to establish alternative limitations and 
standards, further detail the substantive criteria used to evaluate FDF 
variance requests for direct dischargers. 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 facility is fundamentally different. The Agency must determine 
whether, based on one or more of these factors, the facility in 
question is fundamentally different from the facilities and factors 
considered by EPA in developing the nationally applicable effluent 
guidelines. The regulation also lists four other factors (e.g., 
inability to install equipment 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 cost wholly out of proportion to the removal cost 
considered during development of the national limitations, or (b) a 
non-water quality environmental impact (including energy requirements) 
fundamentally more adverse than the impact considered during 
development of the national limits. EPA regulations provide for an FDF 
variance for indirect dischargers at 40 CFR 403.13. The conditions for 
approval of a request to modify applicable pretreatment standards and 
factors considered are the same as those for direct dischargers. The 
legislative history of section 301(n) underscores the necessity for the 
FDF variance applicant to establish eligibility for the variance. EPA's 
regulations at 40 CFR 125.32(b)(1) are explicit in imposing this burden 
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 are, in fact, fundamentally different 
from those factors considered by EPA in establishing the applicable 
guidelines. The criteria for applying for and evaluating applications 
for variances from categorical pretreatment standards are included in 
the pretreatment regulations at 40 CFR 403.13(h)(9). 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 or PSNS.
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 from 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 
guidance 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 Web site at http://www.epa.gov/npdes/pubs/
OWM0469.pdf.
3. Water Quality Variances
    Section 301(g) of the CWA authorizes a variance from BAT effluent 
guidelines for certain nonconventional pollutants due to localized 
environmental factors. These pollutants include ammonia, chlorine, 
color, iron, and total phenols.

XIII. Statutory and Executive Order Reviews

A. Executive Order 12866: Regulatory Planning and Review

    Under Executive Order 12866 (58 FR 51735, October 4, 1993), this 
action is a ``significant regulatory action.'' Accordingly, EPA 
submitted this action to the Office of Management and Budget (OMB) for 
review under EO 12866 and any changes made in response to OMB 
recommendations have been documented in the docket for this action.

B. Paperwork Reduction Act

    The information collection requirements in today's proposed rule 
have been submitted for approval to OMB under the Paperwork Reduction 
Act, 44 U.S.C. 3501 et seq. An Information Collection Request (ICR) 
document has been prepared by EPA and has been assigned EPA ICR No. 
2326.01. Proposed Sec.  449.20 would require airports to collect ADF 
usage data and demonstrate compliance with requirements for ADF capture 
and urea-based pavement deicers.
    EPA estimates it would take an annual average of 14,213 hours and 
$706,051 for airport respondents, and 11,440 hours and $377,420 for 
airline respondents to collect and report the information required by 
the proposed rule. This estimate is based on average labor rates from 
EPA's airport questionnaire for the airport personnel involved in 
collecting and reporting the information required. 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 
proposed rule as part of permit applications, renewals, and NOIs. EPA 
estimates that there would be no start-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 are listed in 40 CFR part 9.
    To comment on the Agency's need for this information, the accuracy 
of the provided burden estimates, and any suggested methods for 
minimizing respondent burden, EPA has established a public docket for 
this rule, which includes this ICR, under Docket ID number EPA-HQ-OW-
2004-0038. Submit any comments related to the ICR to EPA and OMB. See 
ADDRESSES section at the beginning of this notice for where to submit 
comments to EPA. Send comments to OMB at the Office of Information and 
Regulatory Affairs, Office of Management and Budget, 725 17th Street, 
NW., Washington, DC 20503, Attention: Desk Officer for EPA. Since OMB 
is required to make a decision concerning the ICR between 30 and 60 
days after August 28, 2009, a comment to OMB is best assured of having 
its full effect if OMB receives it by September 28, 2009. The final 
rule will respond to any OMB or public comments on the information 
collection requirements contained in this proposal.

C. Regulatory Flexibility Act

    The Regulatory Flexibility Act (RFA) generally requires an agency 
to prepare a regulatory flexibility analysis of any rule subject to 
notice and comment rulemaking requirements under the Administrative 
Procedure Act or any other statute unless the agency certifies that the 
rule will not have a significant economic impact on a substantial 
number of small entities. Small entities

[[Page 44713]]

include small businesses, small organizations, and small governmental 
jurisdictions.
    For the purposes of assessing the impacts of today's proposed rule 
on small entities, EPA determined that all airports expected to be 
within scope are owned by government entities. 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 (5 U.S.C. 601(5)). After matching each airport-owning 
governmental entity with its population, EPA estimates that 34 (8 
unweighted) of 218 (114 unweighted) airports in the scope of the 
proposed rule, or 16 percent, are owned by small government entities. 
EPA projected impacts on these small airports using the revenue test 
described in Section VIII.D.2. EPA found that 3 of the 34 small in-
scope airports are expected to incur annualized compliance costs 
exceeding three percent of airport operating revenues. After 
considering the economic impact of today's proposed rule on small 
entities, including consideration of alternative regulatory approaches, 
I certify that this action will not have significant 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 approximately 2,800 public use 
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 chosen not to regulate any general 
aviation, reliever, or non-primary commercial service airports under 
the proposed regulation. EPA also estimates that in addition to the 34 
small government-owned primary commercial airports, another 42 primary 
commercial airports are owned by small government entities, but will be 
out-of-scope of the proposed regulation because little or no ADF is 
used at those airports.

D. Unfunded Mandates Reform Act

    This proposed rule does not contain a Federal mandate that may 
result in expenditures of $100 million or more for State, local, and 
tribal governments, in the aggregate, or the private sector in any one 
year. As explained in Section VIII and the TDD, the annual cost of the 
proposal is $91.3 million. Thus, this rule is not subject to the 
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. 601). Because 
all in-scope airports are owned by a government or governmental agency, 
the definition for a small airport is identical for the purposes of 
both UMRA and SBREFA. If the rule exceeds annual compliance costs of 
$100 million in aggregate 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 agency plan required under 
sec. 203 because these airports are owned by small governments.
    This rule is also not subject to the requirements of section 203 of 
UMRA because it contains no regulatory requirements that might 
significantly or uniquely affect small governments. The scope of the 
proposed rule focuses on the airports that are the largest users of 
ADF. The proposed rule is not projected to exceed $100 million in 
aggregate annual compliance costs. Further, as discussed in Section 
XIII.C above, EPA has determined the rule will not have significant 
economic impact on a substantial number of small entities.

E. Executive Order 13132: Federalism

    Executive Order 13132, entitled ``Federalism'' (64 FR 43255, August 
10, 1999), requires EPA to develop an accountable process to ensure 
``meaningful and timely input by State and local officials in the 
development of regulatory policies that have federalism implications.'' 
``Policies that have federalism implications'' is defined in the 
Executive Order to include regulations that have ``substantial direct 
effects on the States, on the relationship between the national 
government and the States, or on the distribution of power and 
responsibilities among the various levels of government.''
    This proposed rule does not have federalism implications. It will 
not have substantial direct effects on the States, on the relationship 
between the national government and the States, or on the distribution 
of power and responsibilities among the various levels of government, 
as specified in Executive Order 13132. The proposed rule would not 
alter the basic state-federal scheme established in the Clean Water Act 
under which EPA authorizes states to carry out the NPDES permit 
program. EPA expects the proposed rule would have little effect on the 
relationship between, or the distribution of power and responsibilities 
among, the federal and state governments. Thus, Executive Order 13132 
does not apply to this rule.
    In the spirit of Executive Order 13132, and consistent with EPA 
policy to promote communications between EPA and State and local 
governments, EPA specifically solicits comment on this proposed rule 
from State and local officials.

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

    This proposed rule does not have tribal implications, as specified 
in Executive Order 13175 (65 FR 67249, November 6, 2000). It will not 
have substantial 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 
government and Indian tribes. Today's proposed rule contains no Federal 
mandates for Tribal governments and does not impose any enforceable 
duties on Tribal governments. Thus, Executive Order 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 specifically solicits comment on this proposed 
rule from tribal officials.

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

    EO 13045 (62 FR 19885, April 23, 1997) applies to rules that are 
economically significant according to EO 12866 and involve a health or 
safety risk that may disproportionately affect children. This action is 
not subject to EO 13045 because it does not satisfy either criterion.

H. Executive Order 13211: Energy Effects

    This rule is not a ``significant energy action'' as defined in 
Executive Order 13211, ``Actions Concerning Regulations That 
Significantly Affect Energy 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 energy, as 
described in Section XI of today's proposal. 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.

[[Page 44714]]

I. National Technology Transfer Advancement Act

    Section 12(d) of the National Technology Transfer and Advancement 
Act (NTTAA) of 1995, (Pub. L. 104-113, section 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 standards 
are technical standards (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 decides 
not to use available and applicable voluntary consensus standards.
    The Agency is not aware of any consensus-based technical standards 
for the types of controls contained in today's proposal. EPA welcomes 
comments on this aspect of the proposed rulemaking and, specifically, 
invites the public to identify potentially applicable voluntary 
consensus standards and to explain why such standards should be used in 
this regulation.

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 main provision 
directs federal agencies, to the greatest extent practicable and 
permitted by law, to make environmental justice part of their mission 
by identifying and addressing, as appropriate, disproportionately high 
and adverse human health or environmental effects of their programs, 
policies, and activities on minority populations and low-income 
populations in the United States.
    EPA has determined that this proposed rule will not have 
disproportionately high and adverse human health or environmental 
effects on minority or low-income populations. The proposal would 
increase the level of environmental protection for all affected 
populations without having any disproportionately high and adverse 
human health or environmental effects on any population, including any 
minority or low-income population. The proposed rule will reduce the 
negative effects of discharges from airports to the nation's waters, to 
benefit all of society, including minority communities.

XIV. Solicitation of Data and Comments

A. General and Specific Comment Solicitation

    EPA solicits comments on issues specifically identified in the 
preamble as well as any other issues that are not specifically 
addressed in today's notice. Comments are most helpful when accompanied 
by specific examples or supporting data. In addition, EPA solicits 
information and data on the following topics.
    1. Airport-specific data on current ADF capture rates.
    2. Technology-specific data on ADF capture rates.
    3. Available ADF is defined at proposed 40 CFR 449.2 in terms of 
percentages. EPA solicits comments and data to support any alternative 
figures or flexibility for a permit writer to modify these percentages 
on a case-by-case basis. In addition, please provide comment on whether 
the permit writer should have the flexibility to modify the 80 percent 
default based on site-specific conditions and please suggest 
appropriate criteria on which to base the decision.
    4. The identity and amount of the chemicals in formulations of ADF.
    5. EPA invites comment on other possible minimum threshold criteria 
for the scope of the rule, such as the amount of ADF used, or number of 
deicing operational days. Please provide a rationale for any suggested 
alternate criteria.
    6. Detailed information on additional best management practices 
that improve collection of ADF, and/or control and treatment of ADF 
discharges.
    7. Information on start-up and O&M costs of pollution prevention 
technologies that improve collection of ADF or reduce use of ADF, such 
as infrared heating systems, and similar information about technologies 
that improve the cost-effectiveness of aircraft deicing and anti-icing 
practices.
    8. Information about deicing practices at military facilities, 
including ADF usage, other operational characteristics and 
environmental impacts to help us decide whether to include them in the 
scope of this rule. If EPA decides to expand the scope, it may solicit 
additional public comment on the application of these requirements to 
military facilities.
    9. Recommended operational practices for GRVs and deicing pads.
    10. For the ADF collection requirement in proposed Sec.  449.10, 
EPA may extend the usual 30-day compliance date to allow the additional 
time typically needed by publicly owned airport authorities to arrange 
financing for capital improvements. The extended compliance date could 
be as much as three years from date of promulgation. The Agency invites 
comment on the appropriate compliance period for this provision, and 
recommendations for interim measures.
    11. Site-specific data and documentation on space limitations, 
available adjacent land and possible cost, along with recommendations 
for alternative ADF collection techniques, if deicing pads are not 
feasible.
    12. Environmental impacts or safety issues associated with use of 
alternative pavement deicers instead of urea-based deicers.
    13. To what extent, if any, do airports anticipate they will choose 
to monitor their discharges for ammonia rather than certify non-use of 
urea?
    14. Deicing for safe taxiing. For airports choosing to comply with 
technology specifications as proposed in Sec.  449.20(b)(1), the 
proposed rule would require all deicing activities to be conducted in 
locations were the ADF is actively collected, either by GRV or 
centralized pads, depending on the specific requirements. However, 
there may be situations where ice build-up prevents an aircraft from 
taxiing to the location where collection is conducted. For such 
situations, the proposed rule would allow up to 25 gallons of 
normalized ADF to be applied to allow for safe taxiing, without 
actively collecting the spent ADF. This volume is based on a current 
requirement at Denver International Airport. EPA requests comment on 
whether this is the appropriate ADF amount.
    15. The alternative technology provisions in proposed Sec.  
449.20(b)(2) would require approval by the permit authority. EPA 
requests comment on whether any airports intend to use these 
provisions, and whether these provisions would be burdensome to permit 
authorities.
    16. Criteria used to select data as the basis of the proposed 
effluent limitations for COD and the compliance alternative for 
ammonia. EPA also requests comment on whether data from start-up 
conditions should be included as a basis of the limitations.
    17. Substitution of the weekly average effluent limitation for the 
monthly average effluent limitation for COD. EPA is proposing this 
substitution because of compliance monitoring concerns. EPA requests 
comments that identify other alternatives that may better address the 
issues with compliance monitoring, but still provide ongoing incentive 
for airports to target the system performance to the long-term average 
concentration of COD.

[[Page 44715]]

    18. EPA requests comment on whether there are situations, such as 
extreme weather, in which operational or safety concerns would pose a 
challenge to the complete elimination of urea use for airfield pavement 
deicing. If so, please provide specific data or information documenting 
these concerns.
    19. EPA requests comment on its proposal to treat new runway 
construction at existing airports as new sources. EPA specifically 
requests comment on its proposed determination that a new runway would 
be ``substantially independent of an existing source at the same 
site.'' EPA also requests any data relevant to the question of whether 
the proposed NSPS would pose a barrier to entry for new runway 
construction (e.g., at smaller airports within the rule scope) or 
otherwise pose a barrier to entry for new sources.
    20. EPA requests comment on whether there are situations where it 
may or may not be achievable for an airport with one or more deicing 
pads to use them for all commercial flights without exception. Should 
some provision be included in the rule to accommodate such situations? 
Commenters should give specific examples of such situations and explain 
clearly why it would not be feasible or economically achievable to use 
deicing pads for all commercial flights without exception.
    21. EPA requests comment on whether there are airports in semi-warm 
climates for which de-icing is only required occasionally (at most 
several days per year), and whether it would be appropriate to make 
some provision for such airports, such as including a criterion related 
to ADF usage, number of de-icing days, or departures during certain 
seasons, in the scope criteria for the rule. In suggesting any such 
criteria, commenters should be mindful of implementation issues, such 
as availability and verification of appropriate data.

XV. Guidelines for Submission of Analytical Data

    EPA requests that commenters on today's proposed rule submit 
analytical, flow, and aircraft departure data to supplement data 
collected by the Agency during the regulatory development process. To 
ensure that EPA may effectively evaluate these data, EPA suggests these 
guidelines for submission of data.

A. Types of Data Requested

    EPA requests paired influent and effluent treatment data for each 
of the technologies identified in the technology options (see Section 
VII.B) as well as any additional technologies applicable to the 
treatment of deicing and anti-icing wastewater. EPA prefers paired 
influent and effluent treatment data, but solicits unpaired data as 
well. EPA will not evaluate data from systems treating only non-deicing 
wastewater (e.g., sanitary wastewater).
    For the systems treating deicing wastewater, EPA requests paired 
influent and effluent treatment data from samples of flowing wastewater 
streams. This includes end-of-pipe treatment technologies and in-
process treatment, recycling, or water reuse. If commenters submit only 
effluent data, commenters should provide evidence that the influent is 
highly concentrated. EPA also prefers individual measurements, rather 
than averages, to better evaluate variability, but will consider 
averages if individual measurements are unavailable. EPA prefers that 
the measurements are for 24-hour composite samples, but also will 
consider data for grab samples.
    EPA prefers that commenters submit data in an electronic format. In 
addition to providing the measurement of the pollutant in each sample, 
EPA requests that sites provide the detection limit (rather than 
specifying zero or ``ND'') if the pollutant is not detected in the 
wastestream. Identify each measurement with a sample collection date, 
the sampling point location, and the flow rate at that location. For 
each sample or pollutant, identify the analytical method used.
    In support of the treatment data, commenters should submit the 
following items if they are available: A process diagram of the 
treatment system that includes the sampling point locations; treatment 
chemical addition rates; laboratory reports; influent and effluent flow 
rates for each treatment unit during the sampling period; sludge or 
waste oil generation rates; a brief discussion of the treatment 
technology sampled; and a list of deicing operations contributing to 
the sampled wastestream. If available, information and/or estimates of 
capital cost, annual (operation and maintenance) cost, and treatment 
capacity should be included for each treatment unit within the system. 
If specific flows or costs are not available but can reasonably be 
estimated, commenters should provide the assumptions used for the 
estimation procedure.

B. Analytes Requested

    EPA considered metal, organic, conventional, and other 
nonconventional pollutant parameters for regulation. Based on 
analytical data collected, EPA initially identified 21 pollutants of 
concern for deicing operations (see Section VII.C and the TDD). The 
Agency requests analytical data for any of the pollutants of concern 
and for any other pollutant parameters that commenters believe are of 
concern. Of particular interest are COD, BOD5, glycols, 
ammonia as nitrogen, and pH data. Commenters should submit data 
acquired with EPA or equivalent methods (generally, those approved at 
40 CFR Part 136 for compliance monitoring), and should document the 
analytical method used for all data submissions.

C. Quality Assurance/Quality Control (QA/QC) Requirements

    Although EPA requests and prefers that submissions of analytical 
data include any available documentation of QA/QC procedures, EPA will 
consider data submitted without detailed QA/QC information. If 
commenters sample wastewaters to respond to this proposal, EPA 
encourages them to provide detailed documentation of the QA/QC checks 
for each sample. EPA also requests that collection and analysis of ten 
percent field duplicate samples to assess sampling variability, and 
data for equipment blanks for volatile organic pollutants when 
automatic compositors are used to collect samples.

Appendix A: Abbreviations and Definitions Used in This Document

ADF--Aircraft deicing fluid (includes anti-icing fluid)
AFB--Anaerobic fluidized bed treatment technology
AIP--Airport Improvement Program
BAT--Best available technology economically achievable, as defined 
by sec. 301(b)(2)(A) and sec. 304(b)(2)(B) of the CWA
BOD5--Biochemical oxygen demand
CAFR--Comprehensive annual financial reports
COD--Chemical oxygen demand
CPT--Cost pass-through
CWA--Clean Water Act
DSCR--Debt service coverage ratio
FAA--Federal Aviation Administration
FBO--Fixed base operator
GARB--General airport revenue bonds
LTO--Landing and takeoff cycle
Net income--Operating profit minus interest, taxes, depreciation, 
and non-operating profits and losses
NOI--Notice of Intent to discharge under a general permit (40 CFR 
122.28(b)(2))
NSPS--New Source Performance Standards, as defined by sec. 306 of 
the CWA
O&M--Operations and maintenance
Operating profit--Revenues minus cost of providing those services
Outfall--The mouth of conduit drains and other conduits from which a 
facility effluent discharges into receiving waters

[[Page 44716]]

PFC--Passenger facility charges
Revenues--Money received for services rendered
RFA--Regulatory Flexibility Act
RPM--Revenue passenger miles
RTM--Revenue ton miles
SOFP--Snow or freezing precipitation

List of Subjects in 40 CFR Part 449

    Environmental protection, Airport deicing, Airport, Airline, Waste 
treatment and disposal, Water pollution control.

    Dated: August 17, 2009.
Lisa P. Jackon,
Administrator.

    For the reasons set out in the preamble, title 40, chapter I of the 
Code of Federal Regulations is proposed to be amended by adding part 
449 to read as follows:

PART 449--AIRPORT DEICING POINT SOURCE CATEGORY

Subpart A--Airport Deicing Category
Sec.
449.1 Applicability.
449.2 General definitions.
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

Subpart B--[Reserved]

    Authority: 33 U.S.C. 1311, 1314, 1316, 1318, 1342, 1361 and 
1370.

Subpart A--Airport Deicing Category

Sec.  449.1  Applicability.

    This part applies to discharges of pollutants from deicing 
operations at Primary Airports with at least 1,000 annual scheduled 
commercial air carrier jet departures.

Sec.  449.2  General definitions.

    The following definitions apply to this part:
    Aircraft deicing fluid (ADF) means a fluid applied to aircraft to 
remove or prevent any accumulation of snow or ice on the aircraft. This 
includes deicing and anti-icing fluids.
    Airfield pavement means all paved surfaces on the airside of an 
airport.
    Airside means the part of an airport directly involved in the 
arrival and departure of aircraft, including runways, taxiways, aprons 
and ramps.
    Annual jet departures means the average number of commercial jet 
aircraft that take off from an airport on an annual basis, as tabulated 
by the Federal Aviation Administration, calculated over the five-year 
period prior to submittal of a permit application or NOI.
    Annual normalized ADF usage means the average amount of normalized 
aircraft deicing fluid used annually, calculated over the five year 
period prior to submittal of a permit application or Notice of Intent.
    Available ADF means 80 percent of the sprayed deicing fluid and 10 
percent of the sprayed anti-icing fluid.
    Certification statement means a written submission to the Director 
stating that the discharger does not use airfield deicing products that 
contain urea.
    COD means Chemical Oxygen Demand.
    Deicing for safe taxiing means the minimal extent of deicing 
activity that would remove snow or ice to the level needed to prevent 
damage to a taxiing aircraft, and that is performed at a location not 
having ADF collection equipment.
    Deicing operations mean procedures and practices to remove or 
prevent any accumulation of snow or ice on:
    (1) An aircraft; or
    (2) Paved surfaces within an airport's aircraft movement area 
(runway, taxiway, apron, or ramp).
    New source. For the purpose of the definitions at 40 CFR 122.2 and 
40 CFR 122.29(b)(1), a new source includes:
    (1) Any new Primary Airport constructed after [date of 
promulgation]; and
    (2) Any new runway constructed at a Primary Airport, the deicing 
operations associated with the departures on the new runway and the 
deicing of paved surfaces associated with the new runway.
    Normalized aircraft deicing fluid means ADF less any water added by 
the manufacturer or customer before ADF application.
    Notice of Intent (NOI) means a Notice of Intent to discharge under 
a general permit, as described at 40 CFR 122.28(b)(2).
    Percent capture requirement means the requirement in Sec. Sec.  
449.10 and 449.11 for the permittee to collect at least 60 percent or 
20 percent (as applicable) of the available ADF.
    Primary Airport means an airport defined at 49 U.S.C. 47102 (15).

Sec.  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 
point source subject to this part must comply with the following 
requirements representing the degree of effluent reduction attainable 
by the application of the best available technology economically 
achievable (BAT).
    (a) Collection of runoff from aircraft deicing. (1) All dischargers 
subject to this Part, with 10,000 or greater annual departures and 
annual normalized ADF usage of 460,000 gallons or greater, must collect 
at least 60 percent of available ADF and comply with applicable 
discharge standards in paragraph (b) of this section.
    (2) All dischargers subject to this part, with annual departures of 
10,000 or greater, and annual normalized ADF usage less than 460,000 
gallons, must collect at least 20 percent of the available ADF and 
comply with applicable discharge standards in paragraph (b) of this 
section for all the collected ADF.
    (b) Treatment of collected runoff from aircraft deicing. Except for 
ADF collected and transported to off-site treatment facilities, any 
existing point source subject to this Part must achieve the numeric 
effluent limitations in Table I. These limitations must be met for all 
ADF collected pursuant to paragraphs (a) and (b) of this section. 
Compliance must be measured at the outfall of the on-site treatment 
system utilized for meeting these limitations:

                                            Table I--BAT Limitations
----------------------------------------------------------------------------------------------------------------
                                                                                   Daily maximum  Weekly average
                  Wastestream                    Pollutant or pollutant property       mg/L             mg/L
----------------------------------------------------------------------------------------------------------------
Aircraft Deicing..............................  COD.............................             271             154
----------------------------------------------------------------------------------------------------------------

     (c) Airfield pavement discharges. Except as provided in Sec.  
449.10(d), any discharger subject to this Part must certify that it 
does not use airfield deicing products that contain urea. The 
responsible officer as defined in 40 CFR

[[Page 44717]]

122.22 must sign this certification statement.
    (d) Compliance alternative for airfield BAT requirements. A 
discharger may select and implement the following compliance 
alternative, which is deemed to meet the relevant BAT requirement 
specified in paragraph (c) of this section:
    (1) Airfield pavement discharges must achieve the numeric 
limitations for ammonia in Table II.

                        Table II--BAT Limitations
------------------------------------------------------------------------
                                  Pollutant or pollutant   Daily maximum
          Wastestream                    property              mg/L
------------------------------------------------------------------------
Airfield Pavement Deicing......  Ammonia as Nitrogen....            14.7
------------------------------------------------------------------------

Sec.  449.11  New source performance standards (NSPS).

    New sources subject to this Part must achieve the following new 
source performance standards:
    (a) Collection of runoff from aircraft deicing. All new sources 
subject to this Part, with annual departures of 10,000 or greater, 
shall collect at least 60 percent of available ADF and comply with 
applicable discharge standards in paragraph (b) of this section for all 
collected ADF.
    (b) Treatment of collected runoff from aircraft deicing. Except for 
ADF collected and transported to off-site treatment facilities, any new 
source subject to this Part must achieve the new source performance 
standards in Table III. These standards must be met for all ADF 
collected pursuant to paragraph (a) of this section. Compliance must be 
measured at the outfall of the on-site treatment system utilized for 
meeting these standards:

                                                 Table III--NSPS
----------------------------------------------------------------------------------------------------------------
                                                                                   Daily maximum  Weekly average
                  Wastestream                    Pollutant or pollutant property       mg/L             mg/L
----------------------------------------------------------------------------------------------------------------
Aircraft Deicing..............................  COD.............................             271             154
----------------------------------------------------------------------------------------------------------------

     (c) Airfield pavement discharges. Except as provided in Sec.  
449.11(d), any new source subject to this Part must certify that it 
does not use airfield deicing products that contain urea. The 
responsible officer as defined in 40 CFR 122.22 must sign this 
certification statement.
    (d) Compliance alternative for airfield NSPS requirement. A 
discharger may select and implement the following compliance 
alternative, which is deemed to meet the relevant NSPS requirement 
specified in paragraph (c) of this section:
    (1) Airfield pavement discharges must achieve the numeric 
limitations for ammonia in Table IV.

                             Table IV--NSPS
------------------------------------------------------------------------
                                  Pollutant or pollutant   Daily maximum
          Wastestream                 property  mg/L           mg/L
------------------------------------------------------------------------
Airfield Pavement Deicing......  Ammonia as Nitrogen....            14.7
------------------------------------------------------------------------

     (2) [Reserved]

Sec.  449.20  Monitoring, reporting and recordkeeping requirements.

    (a) Reporting ADF use. Dischargers subject to Sec.  449.10 or Sec.  
449.11 must report the annual normalized ADF usage when submitting a 
permit renewal application.
    (b) Demonstrating the percent of ADF collected. Except as provided 
in 40 CFR 125.30 through 125.32, the Director shall select one of the 
following three methods and specify it in the permit as the required 
method for the permittee to demonstrate compliance with the percent 
capture requirement in Sec.  449.10 or Sec.  449.11 as applicable.
    (1) The permittee shall demonstrate that it is operating and 
maintaining one of the following ADF collection technologies according 
to the technical specifications set forth in paragraphs (b)(1)(i) and 
(ii) of this section. These technical specifications shall be expressly 
set forth as requirements in the permit. This demonstration constitutes 
compliance by the permittee with the applicable percent capture 
requirement without the permittee having to determine the numeric 
percentage of ADF that it has collected.
    (i) Glycol Recovery Vehicle (GRV). Operation of a GRV in accordance 
with these technical specifications is sufficient to demonstrate 
compliance with a requirement to collect at least 20 percent of the 
available ADF:
    (A) All deicing activities shall take place in an area where 
available ADF is actively collected by GRVs, unless deicing for safe 
taxiing is also required. When deicing for safe taxiing is required, 
the volume of ADF used must not exceed 25 gallons of normalized ADF per 
aircraft.
    (B) An emulsifier must be used to aid in ADF recovery, in 
accordance with manufacturer requirements.
    (C) ADF collection by GRV shall commence as soon after deicing 
activities begin, and as is practicable and safe.
    (D) The permittee shall ensure that GRVs are maintained in 
accordance with the manufacturer's specifications and shall inspect 
them at the beginning and end of each deicing season to verify that 
proper maintenance is taking place.
    (ii) Centralized Deicing Pad. Operation of a centralized deicing 
pad

[[Page 44718]]

collection system in accordance with these technical specifications is 
sufficient to demonstrate compliance with a requirement to collect at 
least 60 percent of the available ADF.
    (A) All aircraft deicing shall take place on a centralized deicing 
pad, with the exception of deicing for safe taxiing.
    (B) The volume of ADF used while deicing for safe taxiing shall not 
exceed 25 gallons of normalized ADF per aircraft.
    (C) Drainage valves associated with the centralized deicing pad 
shall be activated to collect spent ADF before deicing activities 
commence.
    (D) Deicing facilities shall be sized to accommodate the airport's 
peak hourly departure rate.
    (E) The minimum width of the centralized deicing pad shall equal 
the upper wingspan of the most demanding airplane design group using 
the deicing pad.
    (F) The minimum length of the centralized deicing pad shall equal 
the fuselage length of the most demanding aircraft using the pad.
    (G) Each centralized deicing pad must be equipped with a fluid 
collection system, such as a perimeter trench and diversion valve, to 
capture spent ADF and ADF-contaminated water.
    (2) Alternate technology or specifications. (i) The Director, on a 
case-by-case basis, may require:
    (A) The use of a different ADF collection technology from the 
technologies specified in paragraph (b)(1) of this section; or
    (B) The use of the same technology, but with different 
specifications for operation and maintenance; or
    (C) The use of an alternative pollution prevention technology that 
may result in a reduction of applied ADF relative to current practices 
at the facility. At the Director's discretion, this reduction may be 
applied towards the collection requirement.
    (ii) The Director shall set forth technical specifications for 
proper operation and maintenance of the chosen collection technology 
and these technical specifications must be expressly included as 
requirements in the permit. The permittee must 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 that it has 
collected. Before the Director may specify an alternate technology 
under this subsection, the permittee must demonstrate to the Director's 
satisfaction that the alternate technology will achieve the percent 
capture requirement applicable under the permit.
    (3) The permittee shall be required to monitor periodically, by 
means deemed acceptable by the Director, and at a frequency determined 
by the Director, the amount of ADF sprayed and the amount of available 
ADF collected in order to determine the compliance with the percent 
capture requirement.
    (c) Airfield pavement discharge certification. Except as provided 
in Sec. Sec.  449.10(d) and 449.11(d), dischargers subject to Sec.  
449.10 or Sec.  449.11 must submit a certification statement that they 
do not use airfield deicing products that contain urea. The discharger 
must provide the certification statement to the Director when 
submitting a permit renewal application and on an annual basis.
    (d) Monitoring requirements. Dischargers subject to Sec.  449.10 or 
Sec.  449.11 must conduct compliance monitoring to demonstrate 
compliance with the COD limitation.
    (1) If a discharger chooses to comply with the compliance 
alternative specified in Sec. Sec.  449.10(d) or 449.11(d), the 
discharger must conduct compliance monitoring to demonstrate compliance 
with the alternative ammonia limitations.
    (e) Recordkeeping. The permittee must maintain on-site, for a 
period of five years from the date they are created, records 
documenting compliance with paragraphs (b) through (d) of this section.

Subpart B--[Reserved]

[FR Doc. E9-20291 Filed 8-27-09; 8:45 am]

BILLING CODE 6560-50-P