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Airport Deicing Loading Database Dictionary 

The Airport Deicing Loading Database calculates pollutant loads associated with the use of 

airfield and aircraft deicing fluids (ADF). EPA developed a methodology to estimate pollutant 

loadings based on the available data. The methodology is detailed in the Technical Development 

Document. The basic steps are as follow: 

 Step 1: Estimate the amount of ADF applied at each airport during a typical 

winter season; 

 Step 2: Calculate the amount of pollutant load associated with the applied 

chemicals, based on the chemical properties of the chemicals; 

 Step 3: Estimate the amount of the applied chemical’s pollutant load that is 

discharged directly, based on the airport’s existing stormwater separation, 

collection, and/or containment system; 

 Step 4: Estimate pollutant loading removals for each EPA regulatory option; 

 Step 5: Scale the loading removal estimates up to represent the entire industry. 

Since the proposed rule, the following changes have been made to the database: 

 Commenters noted that 75 percent would be a better estimate of the amount of 

Type I ADF that is available for discharge. In the Factors table, the value for 

“PercentofADF_Type1_AvailableforDischarge” was changed from 0.8 to 0.75 

and the “PercentofADF_Type1_UnAvailableforDischarge” was changed from 0.2 

to 0.25. 

 An error was identified in the query Pavement Loads – Step 4 (make table for 

average). The average calculation was using pavement deicers purchase values 

for 2003/2004 in the calculation twice and excluding the purchase values for 

2004/2005. The calculation in the query was corrected. 
Table 1. Tables in the Airport Deicing Loading Database 

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Table Name Table Contents Table Data Sou

ADF Usage for Loads The estimated amount and type (propylene glycol type I, 

propylene glycol type IV, ethylene glycol type I, propylene glycol type IV, 

Links to P:\Airport Deicing\Preliminary CoADF Usage Data\Airline Usage Data.mdb 

Airport ID Master list of airports with ID, state, code (153) Links to P:\Airport Deicing\Survey Databa

Track.mdb 

Chemical_info For each deicing chemical, this table lists the chemical 

code, chemical name, density, molecular weight, and the oxygen demand (as determined through stoichiometry equations). 

Chemical oxygen demand estimated at: P:\Cost_Loadings Info\Loads\Methodology\L4_26_07.doc 

factors Value of all of the various factors used in the load 

calculation queries, including: 

 BOD:COD ratio for ADAF stormwater (0.56, 

estimated from sampling data) 

 Percent of Type I ADAF available for discharge (80 

percent) 

 Percent of Type IV ADAF available for discharge 

(10 percent) 

 Percent of pavement deicers available for discharge 

(100 percent) 

BOD:COD relationship described at: P:\AiCost_Loadings Info\Loads\Methodology\SCOD.xls 

Pavement Deicers Average - export to excel 

Presents the pounds of pavement chemicals purchased at each airport for the 2002/2003 2003/2004 and 2004/2005 winter seasons, based on responses to Q28a, Q29a, and Q30a of the airport deicing questionnaire. Includes the average value estimated by Access. This file was exported to excel for further analysis. See “Pavement Deicers Average - import from excel”. 

QUERY: Pavement Loads – Step 4 (make 

Pavement Deicers Average - import from excel 

The “Pavement Deicers Average - export to excel” table was exported to excel and the calculated average was reviewed for each airport and chemical. When the calculated average was not appropriate, the estimated value was updated manually and the update was documented in the table. After each average value was reviewed, the table was imported into Access for use in the loads model. 

P:\Airport Deicing\Preliminary Cost_LoadDatabase\Pavement Deicers Avearge.xls 
Table 1 (Continued). Tables in the Airport Deicing Loading Database 

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Table Name Table Contents Table Data Sou

Percent Capture Category This table was created to categorize the airports into 

broad categories to assist with the percent capture analysis. 

QUERY: Percent Capture series of queries 

Q1-11b Responses from survey production database: number of 

deicing outfalls. 

Links to P:\Airport Deicing\Survey Database\Airport\DENTRY\DATABASE\

Q25-27 Responses from survey production database: average 

number of days of deicing per year for last 3 years. 

Links to P:\Airport Deicing\Survey Database\Airport\DENTRY\DATABASE\

Q28aPavement Responses from survey production database: pavement 

deicer purchase data for 2002/2003 deicing season 

Links to P:\Airport Deicing\Survey Database\Airport\DENTRY\DATABASE\

Q28aPavement_for_loads Q28a was copied to create this table and updates were 

made to estimate -999 and -555 concentration data and to correct obvious errors. The updates were documented in the table. 

TABLE: Q28aPavement 

Q29aPavement Responses from survey production database: pavement 

deicer purchase data for 2003/2004 deicing season 

Links to P:\Airport Deicing\Survey Database\Airport\DENTRY\DATABASE\

Q29aPavement_for_loads Q29a was copied to create this table and updates were 

made to estimate -999 and -555 concentration data and to correct obvious errors. The updates were documented in the table. 

TABLE: Q29aPavement 

Q30aPavement Responses from survey production database: pavement 

deicer purchase data for 2004/2005 deicing season 

Links to P:\Airport Deicing\Survey Database\Airport\DENTRY\DATABASE\

Q30aPavement_for_loads Q30a was copied to create this table and updates were 

made to estimate -999 and -555 concentration data and to correct obvious errors. The updates were documented in the table. 

TABLE: Q30aPavement 

Q32_34-35 Responses from survey production database: discharge 

of deicing stormwater 

Links to P:\Airport Deicing\Survey Database\Airport\DENTRY\DATABASE\

Q33 Responses from survey production database: methods 

used to discharge deicing stormwater 

Links to P:\Airport Deicing\Survey Database\Airport\DENTRY\DATABASE\

Q36 Responses from survey production database: annual 

average volume of deicing stormwater stream 

Links to P:\Airport Deicing\Survey Database\Airport\DENTRY\DATABASE\
Table 1 (Continued). Tables in the Airport Deicing Loading Database 

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Table Name Table Contents Table Data Sou

Q40-42 Responses from survey production database: treatment 

and recovery at the airport 

Links to P:\Airport Deicing\Survey Database\Airport\DENTRY\DATABASE\

Q43a-h Responses from survey production database: Information 

about equalization/storage tanks/ponds at the airport 

Links to P:\Airport Deicing\Survey Database\Airport\DENTRY\DATABASE\

Q43k_m Responses from survey production database: 

Information about equalization/storage tanks/ponds at the airport 

Links to P:\Airport Deicing\Survey Database\Airport\DENTRY\DATABASE\

Q43l Responses from survey production database: 

Information about equalization/storage tanks/ponds at the airport 

Links to P:\Airport Deicing\Survey Database\Airport\DENTRY\DATABASE\
Table 2. Queries Used in the Airport Deicing Loading Database 

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Query Name Query Function Query Calculations Q

ADAF Loads – Step 1 (Type1 Applied) 

Calculates the amount of Type I deicing fluid reported in the “ADF Usage for Loads” table based on the amount of ADF reported and the chemical properties (including density and molecular weight). In addition, estimates the BOD and COD load based on the chemical’s oxygen demand and the BOD:COD relationship. 

Chemical(lbs): [type1(gallons)]*[Density(lbs/gal)] Chemical(gms): [Chemical(lbs)]*[grams/pound] Chemical(moles): [Chemical(gms)]/[MolecularWeight] OxygenRequired(moles): [Chemical(moles)]*[OxygenDemand(moles/mole)] OxygenRequired(lbs): [OxygenRequired(moles)]*[oxygen(o2)MolecularWt]/[grams/pound] ADAF_TYPE1_COD(lbs): [OxygenRequired(lbs)] ADAF_TYPE1_BOD(lbs): [OxygenRequired(lbs)]*[bod:cod] 

 TABLE TABLE TABLE TABLE

ADAF Loads – Step 2 (Type4 Applied) 

Calculates the amount of Type IV deicing fluid reported in the “ADF Usage for Loads” table based on the amount of ADF reported and the chemical properties (including density and molecular weight). In addition, estimates the BOD and COD load based on the chemical’s oxygen demand and the BOD:COD relationship. 

Chemical(lbs): [type1(gallons)]*[Density(lbs/gal)] Chemical(gms): [Chemical(lbs)]*[grams/pound] Chemical(moles): [Chemical(gms)]/[MolecularWeight] OxygenRequired(moles): [Chemical(moles)]*[OxygenDemand(moles/mole)] 

 TABLE TABLE TABLE TABLE
Table 2 (Continued). Queries Used in the Airport Deicing Loading Database 

6 

Query Name Query Function Query Calculations Q

OxygenRequired(lbs): [OxygenRequired(moles)]*[oxygen(o2)MolecularWt]/[grams/pound] ADAF_TYPE4_COD(lbs): [OxygenRequired(lbs)] ADAF_TYPE4_BOD(lbs): [OxygenRequired(lbs)]*[bod:cod] 

ADAF Loads – Step 3 (Total Applied) 

Selects the amount of COD associated with Type I and Type IV ADAF from “ADAF Loads – Step 1 (Type1 Applied)” and “ADAF Loads – Step 2 (Type4 Applied)” into one table 

 QUERY

(Type1 

 QUERY

(Type4 

ADAF Loads – Step 4 (Total Released) 

Estimates the amount of COD associated with ADAF released to direct discharge based on the average amount of ADAF estimated at each airport, the percent capture at each airport, and the factors of how much of the applied ADAF Type I and Type IV are available for discharge. 

ReleasedADAF1: [ADAF_TYPE1_COD(lbs)]*(100-[percentcapture]/100)*[PercentofADF_Type1_AvailableforDischarge] ReleasedADAF4: [ADAF_TYPE4_COD(lbs)]*(100-[percentcapture]/100)*[PercentofADF_Type4_AvailableforDischarge] 

 QUERY

(Total A

 TABLE

ADAF Loads – Step 5 (Total Released by Airport) 

Sums the amount of COD associated with Type I, Type IV, and combined ADAF released at each airport. 

ReleasedADAF1: Sum(ReleasedADAF1) ReleasedADAF4: (ReleasedADAF4) TotalReleasedADAF: Sum([ReleasedADAF1]+[ReleasedADAF4]) 

 QUERY

(Total R

Pavement Loads – Step 1 Calculates the pounds of chemical reported Amount*Conc:  TABLE
Table 2 (Continued). Queries Used in the Airport Deicing Loading Database 

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Query Name Query Function Query Calculations Q

(2002/2003 pounds) in Q28a of the airport deicing questionnaire 

for the 2002/2003 deicing season, using the reported amount and concentration. If the chemical was reported in gallons per season, the chemical density is used to estimate the pounds. 

[Amount]*[Conc]/100 Chemical(lbs): IIf([units]="GAL/SEASON",([Amount* Conc]*[Density(lbs/gal)]),[Amount*Conc]) 

 TABLE TABLE

Pavement Loads – Step 2 (2003/2004 pounds) 

Calculates the pounds of chemical reported in Q29a of the airport deicing questionnaire for the 2003/2004 deicing season, using the reported amount and concentration. If the chemical was reported in gallons per season, the chemical density is used to estimate the pounds. 

Amount*Conc: [Amount]*[Conc]/100 Chemical(lbs): IIf([units]="GAL/SEASON",([Amount* Conc]*[Density(lbs/gal)]),[Amount*Conc]) 

 TABLE TABLE TABLE

Pavement Loads – Step 3 (2004/2005 pounds) 

Calculates the pounds of chemical reported in Q29a of the airport deicing questionnaire for the 2004/2005 deicing season, using the reported amount and concentration. If the chemical was reported in gallons per season, the chemical density is used to estimate the pounds. 

Amount*Conc: [Amount]*[Conc]/100 Chemical(lbs): IIf([units]="GAL/SEASON",([Amount*Conc]*[Density(lbs/gal)]),[Amount*Conc]) 

 TABLE TABLE TABLE

Pavement Loads – Step 4 (make table for average) 

Calculates an average amount of pavement deicer used each winter season, based on the reported pounds of pavement chemicals from the last 3 winter seasons, as estimated in the following queries: 

 Pavement Loads – Step 1 

(2002/2003 pounds) 

 Pavement Loads – Step 2 

(2003/2004 pounds) 

 Pavement Loads – Step 3 

(2004/2005 pounds) 

This query creates the table “Pavement Deicers Average - export to excel”. The table is exported to excel, and the 

Average: ([2002/2003 lbs]+[2003/2004 lbs]+[2003/2004 lbs])/3 

 QUERY

Chemic

 QUERY

(2002/2

 QUERY

(2003/2

 QUERY

(2004/2
Table 2 (Continued). Queries Used in the Airport Deicing Loading Database 

8 

Query Name Query Function Query Calculations Q

calculated averages are reviewed and updated if needed, then the table is imported into the database to estimate pavement deicer loads. 

Pavement Loads – Step 5 (calculate BOD and COD) 

Calculates the amount of COD and BOD associated with pavement deicing chemicals, based on the estimated average amount of pavement deicing chemicals reported and the chemical properties (including molecular weight). In addition, estimates the BOD and COD load based on the chemical’s oxygen demand and the BOD:COD relationship. 

Chemical(gms): [Chemical(lbs)]*[grams/pound] Chemical(moles): [Chemical(gms)]/[MolecularWeight] OxygenRequired(moles): [Chemical(moles)]*[OxygenDemand(moles/mole)] OxygenRequired(lbs): [OxygenRequired(moles)]*[oxygen(o2) MolecularWt]/[grams/pound] COD(lbs): [OxygenRequired(lbs)] BOD(lbs): [OxygenRequired(lbs)]*[bod:cod] 

 TABLE TABLE TABLE

– impor