EPA Regulatory Update
Multi-Sector General Industrial Permit
Airport De-icing and Anti-icing
The U.S. Environmental Protection Agency (EPA) has issued a new Multi-Sector General
Industrial Stormwater Permit that is used by many airports across the United States.
Airports typically either use a General Permit or (as is often the case for larger airports)
have a site-specific or individual permit tailored to that particular airport. This white paper
will discuss the new parts of the General Permit and focus on impacts to airport operations
with an emphasis on airport de-icing and anti-icing. We will also discuss new regulations
on Effluent Guidelines for de-icing materials that is expected to come out as a proposed
rule in early 2009.
The EPA provides minimum standards for storm water programs and allows states to
administer their own program or the EPA can administrate the program for them. The EPA
administers the storm water programs for the following states.
 Massachusetts
 New Hampshire
 New Mexico
 Idaho
 Also many federal facilities and Indian Country Lands
This new General Industrial Permit will be directly applicable to these states but will also
become the basis of the additional state permit programs that are authorized by the EPA to
control storm water discharges within their states. Each state will create its own General
Industrial Permit, which should be available soon. To gain coverage under the General
Permit, a facility needs to prepare a Notice of Intent (NOI). The NOI is to be submitted to
its state or, if on the list above, to the EPA Regional Office. There are several new items in
the NOI form that will be discussed later in this white paper.
Once covered under the permit, the facility must follow all requirements within the permit,
which include the following.
 Requirement to prepare a Storm Water Pollution Prevention Plan (SWPPP)
 Inspection requirements
 Quarterly visual assessment of storm water discharge
 Benchmark sampling requirements (new with this permit)
 Spill and discharge reporting requirements
 Training requirements
 Annual comprehensive site assessment and update of SWPPP
 Annual reporting requirements after completing comprehensive site assessment
(new)
New NOI Requirements
The NOI form is similar to the old one, with several new requirements. The new NOI
requires information relating to Impaired Waters, Endangered Species and Historic
Properties. A discussion of each new requirement follows.
The new NOI requires facilities to identify the receiving stream that receives the storm water from
the facility. The stream must be compared to EPA lists of Impaired Waters, and the facility must also
investigate if the EPA or the state has prepared a Total Maximum Daily Load (TMDL) report for that
stream or stream segment. If a TMDL has been prepared, it must be reviewed to determine if the
storm water effluent from your airport will have an impact on the Impaired Waters. Sampling
programs may be required and treatment systems may also have to be included to meet the TMDL
requirements. This is a site specific situation and may affect your airport. The EPA has prepared a
Water Locator Tool, available on www.epa.gov, that is helpful in identifying the receiving stream
and any water impairment for that stream or stream segment.
The new NOI requires facilities to investigate endangered species that may be present in the
receiving stream. This investigation can often be completed with Internet searches and review of
EPA documents, but it will take some time. The NOI requires the facility to identify the presence of
endangered species and the potential impact to those species in one of six categories.
The new NOI also requires facilities to investigate historic properties that may be present in or near
the receiving stream. Again, this can often be completed with Internet searches and review of EPA
documents. The facility must identify the presence of historic properties and the potential impact to
those properties in one of four categories.
Benchmark Sampling
The permit also includes specific requirements for individual industry sectors. Air Transportation is
presented as Sector S in the permit. The following threshold is important to airport operations.


100,000 gallons of glycol-based deicing or anti-icing materials
100 tons of urea-based de-icing materials
If an airport uses more that this threshold annually, they will have to conduct benchmark sampling of
their outfalls in the first year of the permit. The sample analysis will be compared to the Benchmark
Monitoring Concentration (see below), and if the results fall below the benchmark no additional
sampling or facility upgrades will be necessary. If, however, the sample results fall above the
benchmark, the facility must implement corrective actions and continue regular sampling until the
results fall below the benchmark. This is a significant new requirement in this permit. The
following benchmark limits will apply to facilities that exceed the de-icing threshold.




Biochemical Oxygen Demand (BOD)
Chemical Oxygen Demand (COD)
Ammonia
pH
30 mg/L
120 mg/L
2.14 mg/L
6.0 – 9.0 s.u.
Dates for General Permit Compliance
Facilities that are currently covered under the EPA General Industrial Permit (in states previously
listed) have until January 5, 2009, to submit a new NOI to gain coverage under the new General
Industrial Permit. Any new facilities that start discharging between October 30, 2008, and January 5,
2009, should submit their NOI as soon as possible, but no later than January 5, 2009. Going forward
after January 5, 2009, new facilities will have a minimum of 60 days prior to commencing discharge
or a minimum of 30 days prior to commencing discharge if their SWPPP is posted on the Internet.
Each state that coordinates its own storm water program will produce its own General Industrial
Permit and will have compliance dates accordingly. Keep alert to your individual state programs for
guidance. If you are currently covered under a state sponsored General Industrial Permit, the state
will likely be sending notifications in the mail.
Other EPA Actions on the Horizon – Effluent Guidelines
The other important EPA de-icing regulatory development concerns Effluent Guidelines. These
regulatory limits are technology-based regulations to control industrial discharges. These regulations
are designed to protect human health and enhance water quality. The guidelines are issued for
industry groups and in this case will be directed toward airports with de-icing activity (there will
likely be some usage-based limits, see below). These are stronger regulations than the Benchmark
Concentrations in the General Permit, and they will be strict limits enforceable by fines and other
actions. In comparison, the Benchmark Concentrations discussed above will require the facility to
work with the EPA to reduce their BOD and COD numbers followed by resampling, but does not
include legal penalties. If a facility exceeds an Effluent Guideline, they could be fined and the EPA
could take further action, including shutting down the facility.
The EPA has been working on Airport De-icing Effluent Guidelines for some time and has solicited
comments several times over the last three years. Over this period, the EPA has worked closely with
aviation industry associations. The Effluent Guidelines are still being drafted at the EPA, but the
agency expects to issue a proposed rule later in 2008 or early 2009. There will be a comment period,
and the EPA will publish a final rule in late 2009 or 2010. Once the Final Guidelines are published,
they will be incorporated into yet another new version of the General Industrial Permit and each state
will follow suit as described above. Some airports have Individual Permits that also will require reworking to incorporate the new Effluent Guideline limits once they become final. The EPA
encourages facilities to provide comments and feedback during the comment period, and we
encourage all airports to participate.
As mentioned above, the specifics of the proposed Effluent Guidelines are not known, but here are a
few items that are likely to be included.
The Guidelines will probably have some form of discharge limits similar to the Benchmarks required
by the General Industrial Permit. The EPA recognizes that the larger airports with scheduled airline
traffic and/or significant air cargo operations tend to be the larger users of de-icing and anti-icing
materials. Thus, the regulations will be directed towards those larger airports with the application of
glycol use thresholds. The EPA has stated verbally that the intention of the Effluent Guidelines will
not be directed toward general aviation airports. Once the proposed Effluent Guidelines are
published, we will know what the usage thresholds will be and how they will apply to airports across
the county.
The Effluent Guidelines will likely have some form of concentration limit such as BOD and/or COD
similar to the Benchmark Sampling requirements. The Guidelines will also likely have some
requirement for percent capture of glycol used. Once the material is captured, the Guidelines will
not likely specify what airports are to do with the material. Several options are noted below.

Recycle the glycol material. There are already several recycling operations at or near
airports including an excellent example at the Detroit Metro Airport in Michigan.

Treat the recovered glycol material in a biological treatment system on the airport property.
This will require a National Pollutant Discharge Elimination System (NPDES) permit for the
treatment system discharge and the Effluent Guidelines will apply to the treated effluent.

Discharge the glycol material to the Publicly Owned Treatment Works (POTW) or basically
the sanitary sewer system. This has some unique issues that will have to be addressed at
each location, such as Can the system accept the high concentrations of glycol; Can the
system accept the volume of water/glycol mixture which will include a significant amount of
rainwater and/or snow melt; and What will the additional charges be for accepting this flow?
Finally, the Effluent Guidelines will likely address urea-based airfield pavement de-icing materials.
For airports that choose to install permanent on-site collection or treatment facilities, the project
costs may be significant. Additionally, it will take a great deal of time to procure the funding and
design and construct such a facility. The EPA has verbally stated that they understand this issue and
will work with facilities on a case-by-case basis to achieve compliance. With that however, the EPA
has stated that Effluent Guidelines typically do not include compliance dates projected into the
future, and once the Guidelines become final, they expect facilities to comply with the law.
More information is available on the EPA Web site at www.epa.gov/guide/airport.