able
o
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=
)
/
(


Default Value
Parameter
Method B
Method C
Units
Risk


Hazard Quotient
HQ 1
1 unitless
Toxicological Parameters


Oral Reference Dose
RfD
o
chemical-specific chemical-specific mg/kg-day
Inhalation Correction Factor
INH chemical-specific
chemical-specific unitless
Exposure Parameters


Average Body Weight
ABW 16
70 kg
Averaging Time
AT 6
6 years
Exposure Duration
ED 6
6 years
Drinking Water Ingestion Rate
DWIR 1
2 liters/day
Drinking Water Fraction
DWF 1
1 unitless
Unit Conversion Factors


Unit Conversion Factor
UCF 1,000
1,000 �g/mg


NOTE: Default values highlighted in green differ for Method B and Method C.


Carcinogens: Equation 720-2

DWF
INH
ED
DWIR
CPF
UCF
AT
ABW
RISK
l
ug
Level
Cleanup
Water
Ground
Potable
o
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=
)
/
(


Default Value
Parameter
Method B
Method C
Units
Risk


Carcinogenic Risk
RISK
1 x 10
-6

1 x 10
-5
unitless
Toxicological Parameters


Oral Cancer Potency Factor
CPF
o
chemical-specific chemical-specific kg-day/mg
Inhalation Correction Factor
INH chemical-specific
chemical-specific unitless
Exposure Parameters


Average Body Weight
ABW 70
70
kg
Averaging Time
AT 75
75 years
Exposure Duration
ED 30
30 years
Drinking Water Ingestion Rate
DWIR 2
2 liters/day
Drinking Water Fraction
DWF 1
1 unitless
Unit Conversion Factors


Unit Conversion Factor
UCF 1,000
1,000 �g/mg


NOTE: Default values highlighted in green differ for Method B and Method C. Potable Ground Water Cleanup Levels

Summary of Default Values
for calculating
Concentrations Protective of Human Health

Default Value
Method B
Method C
Modifiable?
Parameter
Noncarcinogen
Carcinogen
Noncarcinogen
Carcinogen
Cleanup
Level
Remediation
Level
Risk Noncarcinogens
Hazard Quotient
HQ
1 (unitless)
1
(unitless)


Hazard Index (Total)
HI
1 (unitless)
1
(unitless)


Risk Carcinogens
Single Substance
RISK

1 x 10
-6
(unitless)

1 x 10
-5
(unitless)

Total Site Risk


1 x 10
-5
(unitless)

1 x 10
-5
(unitless)

Toxicological Parameters
Oral Reference Dose
RfD
o
Chemical-specific
Chemical-specific x
x
Oral Cancer Potency Factor
CPF
o

Chemical-specific Chemical-specific
x x
Inhalation Correction Factor
INH
Chemical-specific
Chemical-specific
Chemical-specific Chemical-specific
x
x
Exposure Parameters
Average Body Weight
ABW
16 kg
70 kg
70 kg
70 kg

x
Exposure Duration
ED
6 years
30 years
6 years
30 years

x
Averaging Time
AT
6 years
75 years
6 years
75 years

x
Drinking Water Ingestion Rate
DWIR
1 liter/day
2 liters/day
2 liters/day
2 liters/day

x
Drinking Water Fraction
DWF
1 (unitless)
1 (unitless)
1 (unitless)
1 (unitless)

x
Unit Conversion Factors
Unit Conversion Factor
UCF
1,000 �g/mg
1,000 �g/mg
1,000 �g/mg
1,000 �g/mg



NOTE: Default values highlighted in green differ for Method B and Method C.