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From page 11... ... 11 Deicer treatment systems are implemented primarily because the pollutants contained in the deicer-affected runoff are greater than the allowable pollutant in discharges to surface waters or groundwater. When assessing what deicer treatment is needed (see Figure 8) Read the entire page →
From page 12... ... 12 Guidance for Treatment of Airport Stormwater Containing Deicers 2.1.1.1 Overview of Applicable U.S. Regulations The federal Water Pollution Control Act amendments of 1972 and subsequent amendments, commonly known as the Clean Water Act (CWA) Read the entire page →
From page 13... ... Defining Deicer Treatment Needs and Implementation Constraints 13 Under the CWA, the effluent limits in NPDES permits are based on two principles: (1) all wastewater discharges must be treated with the best treatment technology economically achievable, regardless of the condition of the receiving water (which results in technology-based limits) Read the entire page →
From page 14... ... 14 Guidance for Treatment of Airport Stormwater Containing Deicers regardless of their location in the United States. In 2012, the EPA published final technology-based effluent limitations guidelines (ELGs) Read the entire page →
From page 15... ... Defining Deicer Treatment Needs and Implementation Constraints 15 control authority for implementation of its pretreatment program, much as a state agency is the control authority for its NPDES permit program. A central requirement of pretreatment programs is the development of local limits applicable to discharges from industries, which will prevent interference with operation of the treatment processes or sludge use or disposal, and which will prevent pass-through of pollutants that could result in violation of NPDES permit limits or water quality criteria in the receiving water body. Read the entire page →
From page 16... ... 16 Guidance for Treatment of Airport Stormwater Containing Deicers 2.1.1.6 Applying for Discharge Permits The airport must submit an application for the appropriate discharge permit to the control authority: either the state agency or EPA for an NPDES permit, or the local POTW for an IU discharge permit. In some cases, the application will be for modification of an existing permit. Read the entire page →
From page 17... ... Defining Deicer Treatment Needs and Implementation Constraints 17 2.1.2 Documenting All Applicable Limits and Conditions from Permits and Agreements NPDES permits regulating discharges to surface waters, IU permits regulating discharges to sanitary sewers, and other permits may trigger the need for an airport to monitor stormwater discharges and to meet effluent limitations. Privately run facilities that accept deicer-affected stormwater for treatment or recycling may establish limits on the characteristics and quantity of the stormwater. Read the entire page →
From page 18... ... 18 Guidance for Treatment of Airport Stormwater Containing Deicers • Parameters might be limited on multiple timescales (e.g., maximum and monthly average) Read the entire page →
From page 19... ... Defining Deicer Treatment Needs and Implementation Constraints 19 integrated into the contracts between the airport and the firm managing recycling operations at the airport. • Minimum glycol concentration requirements. Read the entire page →
From page 20... ... 20 Guidance for Treatment of Airport Stormwater Containing Deicers Example for Establishing Governing Limits from Permits and Agreements An airport has an NPDES permit with concentration and mass loading limits for BOD5 and concentration limits for PG (shown below) Read the entire page →
From page 21... ... Defining Deicer Treatment Needs and Implementation Constraints 21 deicers, are most often the principal drivers for selecting, sizing, and operating deicer treatment technologies and systems. The primary deicer constituents can directly contribute to the presence of organics, nutrients, solids, and physical properties, as shown in Figure 11. Read the entire page →
From page 22... ... 22 Guidance for Treatment of Airport Stormwater Containing Deicers can be recycled by the typically used recycling technologies; however, the economics of recycling are affected at lower concentrations because of the increased volumes of water that need to be processed. A general rule of thumb is that minimum EG or PG concentrations of 1% are needed to make recycling economical. Read the entire page →
From page 23... ... Defining Deicer Treatment Needs and Implementation Constraints 23 Biochemical Oxygen Demand: BOD is the quantity of oxygen required when organic and nitrogen-based compounds in stormwater are biologically oxidized by bacteria. The BOD concentration is used as a measure of the total concentrations of biodegradable compounds in the sample. Read the entire page →
From page 24... ... 24 Guidance for Treatment of Airport Stormwater Containing Deicers inaccuracies from factors such as interfering constituents, non-acclimated biological seed, and improper test dilutions. COD analyses are not affected by these conditions. Read the entire page →
From page 25... ... Defining Deicer Treatment Needs and Implementation Constraints 25 Excessive concentrations of TDS can potentially inhibit biological activity and could lead to scaling in physical treatment systems. Biological treatment systems will not remove TDS. Read the entire page →
From page 26... ... 26 Guidance for Treatment of Airport Stormwater Containing Deicers Although detailed guidance on stormwater characterization analyses cannot be presented here, an overview of the stormwater characterization needs is provided because it is critical to effective selection and implementation of deicer treatment systems. 2.2.2.1 Defining the Water Quality and Quantity Parameters An important step in characterizing stormwater for assessment of deicer treatment needs is to identify the water quality and quantity parameters applicable to your treatment situation. Read the entire page →
From page 27... ... Defining Deicer Treatment Needs and Implementation Constraints 27 More sophisticated modeling methods or extensive sampling requires additional up-front cost but can significantly reduce the risk that treatment is oversized (resulting in unnecessary cost) or undersized (resulting in more compliance risk) Read the entire page →
From page 28... ... 28 Guidance for Treatment of Airport Stormwater Containing Deicers 2.3.1 Siting Constraints As part of the constraints analysis, an assessment of potential treatment system sites should be conducted. Siting considerations include: • Proximity to collected and stored stormwater; • Proximity to outfalls and sanitary sewers; • Proximity to utilities, including power, water, and natural gas; • Proximity to restricted airfield areas; • Clashes with existing utilities; • Presence of protected water resource land uses, such as wetlands; • Stormwater management requirements; • Geotechnical and hydrogeological characteristics; • Presence of environmental contamination; • Planned land uses such as may be found in the airport master plan; and • Accessibility. Read the entire page →
From page 29... ... Defining Deicer Treatment Needs and Implementation Constraints 29 In addition to local construction regulations, construction at an airport is regulated by the FAA, primarily to mitigate hazards to aircraft operations. To reduce obstructions to airport operations, the FAA regulations generally specify minimum distances and maximum allowable heights for objects at or near an airport. Read the entire page →
From page 30... ... 30 Guidance for Treatment of Airport Stormwater Containing Deicers 2.3.2 Operational Constraints Limitations on Open-Water Surfaces Some deicer treatment technologies, like activated sludge or aerated lagoons, are typically designed with open-water surfaces. Open-water surfaces can be wildlife attractants and provide reflectivity issues. Read the entire page →
From page 31... ... Defining Deicer Treatment Needs and Implementation Constraints 31 Aesthetics can sometimes play a factor in treatment technology decisions. Most often, accommodations for aesthetic preferences can be made in the design phases, but occasionally, aesthetic issues can be a cause for elimination of certain technologies during the technology screening phases. Read the entire page →
From page 32... ... 32 Guidance for Treatment of Airport Stormwater Containing Deicers 2. Documentation of the governing parameters, numeric limits, and conditions obtained from a comprehensive analysis. Read the entire page →
From page 33... ... Defining Deicer Treatment Needs and Implementation Constraints 33 A criteria worksheet for airport site and operational constraints provides the following value: 1. A list of potential siting and operational considerations to promote discussion by stakeholders, 2. Read the entire page →

From page 11...

... 11 Deicer treatment systems are implemented primarily because the pollutants contained in the deicer-affected runoff are greater than the allowable pollutant in discharges to surface waters or groundwater. When assessing what deicer treatment is needed (see Figure 8)