# 1 Airport Deicing Loading Database Dictionary

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

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

loadings based on the available data. The met hodology is detailed in th e Technical Development

Document. The basic steps are as follow:

 

# Step 1: Estimate the amount of ADF a pplied at each airport during a typical

winter season;

 

# Step 2: Calculate the amount of polluta nt load associated with the applied

chemicals, based on the chemical properties of the chemicals;

 

# Step 3: Estimate the amount of the applie d chemical’s polluta nt load that is

discharged directly, based on the airp ort’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 availabl e for discharge. In the Factors table, the value for

“PercentofADF_Type1_AvailableforDischa rge” was changed from 0.8 to 0.75

and the “PercentofADF_Type1_UnAvailabl eforDischarge” 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 usi ng 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 Database2Table NameTable ContentsTable Data SourceADF 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 Cost_Loadings Info\AirlineADF Usage Data\Airline Usage Data.mdbAirport ID Master list of airports with ID, state, code (153) Links to P:\Airport Deicing\SurveyDatabase\Airport\Airport SurveyTrack.mdbChemical_info For each deicing chemical, this table lists the chemicalcode, chemical name, density, molecular weight, and theoxygen demand (as determined through stoichiometryequations).Chemical oxygen demand estimated at: P:\Airport Deicing\PreliminaryCost_Loadings Info\Loads\Methodology\Loading Calc Approaches4_26_07.docfactors Value of all of the various factors used in the loadcalculation queries, including:BOD:COD ratio for ADAF stormwater (0.56,estimated from sampling data)Percent of Type I ADAF available for discharge (80percent)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:\Airport Deicing\PreliminaryCost_Loadings Info\Loads\Methodology\Sampling Data BOD &COD.xlsPavement Deicers Average -export to excelPresents the pounds of pavement chemicals purchased ateach airport for the 2002/20032003/2004 and 2004/2005winter seasons, based on responses to Q28a, Q29a, andQ30a of the airport deicing questionnaire. Includes theaverage value estimated by Access. This file wasexported to excel for further analysis. See “PavementDeicers Average - import from excel”.QUERY: Pavement Loads – Step 4 (make table for average)Pavement Deicers Average -import from excelThe “Pavement Deicers Average - export to excel” tablewas exported to excel and the calculated average wasreviewed for each airportand chemical. When thecalculated average was not appropriate, the estimatedvalue was updated manually and the update wasdocumented in the table. After each average value wasreviewed, the table was imported into Access for use inthe loads model.P:\Airport Deicing\Preliminary Cost_Loadings Info\Loads\LoadsDatabase\Pavement Deicers Avearge.xlsTable 1 (Continued). Tables in the Airport Deicing Loading Database3Table NameTable ContentsTable Data SourcePercent Capture Category This table wascreated to categorize the airports intobroad categories to assist with the percent captureanalysis.QUERY: Percent Capture series of queries creates this tableQ1-11b Responses from survey production database: number ofdeicing outfalls.Links to P:\Airport Deicing\SurveyDatabase\Airport\DENTRY\DATABASE\Prod.mdbQ25-27 Responses from survey production database: averagenumber of days of deicing per year for last 3 years.Links to P:\Airport Deicing\SurveyDatabase\Airport\DENTRY\DATABASE\Prod.mdbQ28aPavement Responses from survey production database: pavementdeicer purchase data for 2002/2003 deicing seasonLinks to P:\Airport Deicing\SurveyDatabase\Airport\DENTRY\DATABASE\Prod.mdbQ28aPavement_for_loads Q28a was copied to create this table and updates weremade to estimate -999 and -555 concentration data andto correct obvious errors. The updates were documentedin the table.TABLE: Q28aPavementQ29aPavement Responses from survey production database: pavementdeicer purchase data for 2003/2004 deicing seasonLinks to P:\Airport Deicing\SurveyDatabase\Airport\DENTRY\DATABASE\Prod.mdbQ29aPavement_for_loads Q29a was copied to create this table and updates weremade to estimate -999 and -555 concentration data andto correct obvious errors. The updates were documentedin the table.TABLE: Q29aPavementQ30aPavement Responses from survey production database: pavementdeicer purchase data for 2004/2005 deicing seasonLinks to P:\Airport Deicing\SurveyDatabase\Airport\DENTRY\DATABASE\Prod.mdbQ30aPavement_for_loads Q30a was copied to create this table and updates weremade to estimate -999 and -555 concentration data andto correct obvious errors. The updates were documentedin the table.TABLE: Q30aPavementQ32_34-35 Responses from survey production database: dischargeof deicing stormwaterLinks to P:\Airport Deicing\SurveyDatabase\Airport\DENTRY\DATABASE\Prod.mdbQ33 Responses from survey production database: methodsused to discharge deicing stormwaterLinks to P:\Airport Deicing\SurveyDatabase\Airport\DENTRY\DATABASE\Prod.mdbQ36 Responses from survey production database: annualaverage volume of deicing stormwater streamLinks to P:\Airport Deicing\SurveyDatabase\Airport\DENTRY\DATABASE\Prod.mdbTable 1 (Continued). Tables in the Airport Deicing Loading Database4Table NameTable ContentsTable Data SourceQ40-42 Responses from survey production database: treatmentand recovery at the airportLinks to P:\Airport Deicing\SurveyDatabase\Airport\DENTRY\DATABASE\Prod.mdbQ43a-h Responses from survey production database: Informationabout equalization/storage tanks/ponds at the airportLinks to P:\Airport Deicing\SurveyDatabase\Airport\DENTRY\DATABASE\Prod.mdbQ43k_m Responses from survey production database:Information about equalization/storage tanks/ponds atthe airportLinks to P:\Airport Deicing\SurveyDatabase\Airport\DENTRY\DATABASE\Prod.mdbQ43l Responses from survey production database:Information about equalization/storage tanks/ponds atthe airportLinks to P:\Airport Deicing\SurveyDatabase\Airport\DENTRY\DATABASE\Prod.mdbTable 2. Queries Used in the Airport Deicing Loading Database5Query NameQuery FunctionQuery CalculationsQuery Data SourcesADAF Loads – Step 1(Type1 Applied)Calculates the amount of Type I deicingfluid reported in the “ADF Usage forLoads” table based on the amount of ADFreported and the chemical properties(including density and molecular weight).In addition, estimates the BOD and CODload based on the chemical’s oxygendemand 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: Airport_IDTABLE: ADF Usage for LoadsTABLE: Chemical InfoTABLE: FactorsADAF Loads – Step 2(Type4 Applied)Calculates the amount of Type IV deicingfluid reported in the “ADF Usage forLoads” table based on the amount of ADFreported and the chemical properties(including density and molecular weight).In addition, estimates the BOD and CODload based on the chemical’s oxygendemand 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: Airport_IDTABLE: ADF Usage for LoadsTABLE: Chemical InfoTABLE: FactorsTable 2 (Continued). Queries Used inthe Airport Deicing Loading Database6Query NameQuery FunctionQuery CalculationsQuery Data SourcesOxygenRequired(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 (TotalApplied)Selects the amount ofCOD associated withType I and Type IV ADAF from “ADAFLoads – Step 1 (Type1 Applied)” and“ADAF Loads – Step 2 (Type4 Applied)”into one tableQUERY: ADAF Loads – Step 1(Type1 Applied)QUERY: ADAF Loads – Step 2(Type4 Applied)ADAF Loads – Step 4 (TotalReleased)Estimates the amount of COD associatedwith ADAF released to direct dischargebased on the average amount of ADAFestimated at each airport, the percentcapture at each airport,and the factors ofhow much of the applied ADAF Type I andType 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: ADAF Loads – Step 3(Total Applied)TABLE: Percent Capture)ADAF Loads – Step 5 (TotalReleased by Airport)Sums the amount of COD associated withType I, Type IV, and combined ADAFreleased at each airport.ReleasedADAF1:Sum(ReleasedADAF1)ReleasedADAF4:(ReleasedADAF4)TotalReleasedADAF:Sum([ReleasedADAF1]+[ReleasedADAF4])QUERY: ADAF Loads – Step 4(Total Released)Pavement Loads – Step 1 Calculates the pounds of chemical reported Amount*Conc:TABLE: FactorsTable 2 (Continued). Queries Used inthe Airport Deicing Loading Database7Query NameQuery FunctionQuery CalculationsQuery Data Sources(2002/2003 pounds) in Q28a of the airport deicing questionnairefor the 2002/2003 deicing season, using thereported amount and concentration. If thechemical was reported in gallons perseason, the chemical density is used toestimate the pounds.[Amount]*[Conc]/100Chemical(lbs):IIf([units]="GAL/SEASON",([Amount*Conc]*[Density(lbs/gal)]),[Amount*Conc])TABLE: Q28aPavement_for_loadsTABLE: Chemical InfoPavement Loads – Step 2(2003/2004 pounds)Calculates the poundsof chemical reportedin Q29a of the airport deicing questionnairefor the 2003/2004 deicing season, using thereported amount and concentration. If thechemical was reported in gallons perseason, the chemical density is used toestimate the pounds.Amount*Conc:[Amount]*[Conc]/100Chemical(lbs):IIf([units]="GAL/SEASON",([Amount*Conc]*[Density(lbs/gal)]),[Amount*Conc])TABLE: FactorsTABLE: Q29aPavement_for_loadsTABLE: Chemical InfoPavement Loads – Step 3(2004/2005 pounds)Calculates the poundsof chemical reportedin Q29a of the airport deicing questionnairefor the 2004/2005 deicing season, using thereported amount and concentration. If thechemical was reported in gallons perseason, the chemical density is used toestimate the pounds.Amount*Conc:[Amount]*[Conc]/100Chemical(lbs):IIf([units]="GAL/SEASON",([Amount*Conc]*[Density(lbs/gal)]),[Amount*Conc])TABLE: FactorsTABLE: Q30aPavement_for_loadsTABLE: Chemical InfoPavement Loads – Step 4(make table for average)Calculates an average amount of pavementdeicer used each winter season, based onthe reported pounds of pavement chemicalsfrom the last 3 winter seasons, as estimatedin 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 “PavementDeicers Average - export to excel”.The table is exported to excel, and theAverage:([2002/2003 lbs]+[2003/2004lbs]+[2003/2004 lbs])/3QUERY: Pavement Deicers MasterChemical ListQUERY: Pavement Loads – Step 1(2002/2003 pounds)QUERY: Pavement Loads – Step 2(2003/2004 pounds)QUERY: Pavement Loads – Step 3(2004/2005 pounds)Table 2 (Continued). Queries Used inthe Airport Deicing Loading Database8Query NameQuery FunctionQuery CalculationsQuery Data Sourcescalculated averages are reviewed andupdated if needed, then the table isimported into the database to estimatepavement deicer loads.Pavement Loads – Step 5(calculate BOD and COD)Calculates the amount of COD and BODassociated with pavement deicingchemicals, based on the estimated averageamount of pavement deicing chemicalsreported and the chemical properties(including molecular weight). In addition,estimates the BOD and COD load based onthe chemical’s oxygen demand and theBOD: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: FactorsTABLE: Chemical InfoTABLE: Pavement Deicers Average– import from excel