Michigan Administrative Code › Department - Environmental Quality › Remediation and Redevelopment Division › Environmental Contamination Response Activity › CLEANUP CRITERIA REQUIREMENTS FOR RESPONSE ACTIVITY › Section R. 299.20 - Generic cleanup criteria for soil based on direct contact

Current through Vol. 24-12, July 15, 2024
Rule 20.
(1)
				  Cleanup criteria for soil based on direct contact shall be calculated for the
				  generic residential category according to the following algorithms, except as
				  provided in R 299.34(3):
EQUATION FOR CARCINOGENS:
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where,
DCC
(Direct contact criterion)
= chemical-specific, ug/kg or ppb
TR
(Target risk level)
= 10-5
AT
(Averaging time)
= 25,550 days (70 years x 365 days/year)
CF
(Conversion factor)
= 1E+9 ug/kg
SF
(Oral cancer slope factor)
= chemical-specific
								(mg/kg-day)-1
EFi
(Ingestion exposure frequency)
= 350 days/year
IF
(Age-adjusted soil ingestion factor)
= 114 mg-year/kg-day*
AEi
(Ingestion absorption efficiency)
= chemical-specific or default specified at R
								299.20(3)
EFd
(Dermal exposure frequency)
= 245 days/year
DF
(Age-adjusted soil dermal factor)
= 353 mg-year/kg-day**
AEd
(Dermal absorption efficiency)
= chemical-specific or default specified at R
								299.20(3)
EQUATIONS FOR NONCARCINOGENS:
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where,
DCC
(Direct contact criterion)
= chemical-specific (ug/kg or ppb)
THQ
(Target hazard quotient)
= 1
RfD
(Oral reference dose)
= chemical-specific mg/kg-/day
AT
(Averaging time)
= 10,950 days (30 years x 365 days/year)
CF
(Conversion factor)
= 1E+9 ug/kg
RSC
(Relative source contribution)
= 1
EFi
(Ingestion exposure frequency)
= 350 days/year
IF
(Age-adjusted soil ingestion factor)
= 114 mg-year/kg-day*
AEi
(Ingestion absorption efficiency)
= chemical-specific or default specified at R
								299.20(3)
EFd
(Dermal exposure frequency)
= 245 days/year
DF
(Age-adjusted soil dermal factor)
= 353 mg-year/kg-day**
AEd
(Dermal absorption efficiency)
= chemical-specific or default specified at R
								299.20(3)
and,
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where,
IRsoil/age 1-6
(Soil ingestion rate)
= 200 mg/day
EDage 1-6
(Exposure duration)
= 6 years
BWage 1-6
(Body weight)
= 15 kg
IRadult
(Soil ingestion rate)
= 100 mg/day
EDadult
(Exposure duration)
= 24 years
BWadult
(Body weight)
= 70 kg
and,
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where,
SAage 1-6
(Skin surface area)
= 2,670 cm2/dayevent
EV
(Event frequency)
= 1 event/day
AFage 1-6
(Soil adherence factor)
= 0.2 mg/cm2
EDage 1-6
(Exposure duration)
= 6 years
BWage 1-6
(Body weight)
= 15 kg
SAadult
(Skin surface area)
= 5,800 cm2/dayevent
AFadult
(Soil adherence factor)
= 0.07 mg/cm2
EDadult
(Exposure duration)
= 24 years
BWadult
(Body weight)
= 70 kg
(2) Cleanup
				  criteria for soil based on direct contact shall be calculated for the generic
				  nonresidential category according to the following algorithms, except as
				  provided in R 299.34(3):
EQUATION FOR CARCINOGENS:
Click Here To View
					 Image
where,
DCC
(Direct contact criterion)
= chemical-specific, ug/kg or ppb
TR
(Target risk level)
= 10-5
BW
(Body weight)
= 70 kg
AT
(Averaging time)
= 25,550 days (70 years x 365 days/year)
CF
(Conversion factor)
= 1E+9 ug/kg
SF
(Oral cancer slope factor)
= chemical-specific
								(mg/kg-day)-1
ED
(Exposure duration)
= 21 years
EFi
(Ingestion exposure frequency)
= 245 days/year
IRs
(Soil ingestion rate)
= 100 mg/day (residential)
AEi
(Ingestion absorption efficiency)
= chemical-specific or default specified at R
								299.20(3)
EFd
(Dermal exposure frequency)
= 160 days/year
SA
(Skin surface area)
= 3,300 cm2/day event
EV
(Event frequency)
= 1 event/day
AF
(Soil adherence factor)
= 0.2 mg/cm2
								(nonresidential)
AEd
(Dermal absorption efficiency)
= chemical-specific or default specified at R
								299.20(3)
EQUATION FOR NONCARCINOGENS:
Click Here To View
					 Image
where,
DCC
(Direct contact criterion)
= chemical-specific, ug/kg or ppb
THQ
(Target hazard quotient)
= 1
RfD
(Oral reference dose)
= chemical-specific, mg/kg-/day
BW
(Body weight)
= 70 kg
AT
(Averaging time)
= 7,665 days (21 years x 365 days/year)
CF
(Conversion factor)
= 1E+9 ug/kg
RSC
(Relative source contribution)
= 1
ED
(Exposure duration)
= 21 years
EFi
(Ingestion exposure frequency)
= 245 days/year
IRs
(Soil ingestion rate)
= 100 mg/day
AEi
(Ingestion absorption efficiency)
= chemical-specific or default specified at R
								299.20(3)
EFd
(Dermal exposure frequency)
= 160 days/year
SA
(Skin surface area)
= 3,300 cm2/day event
EV
(Event frequency)
= 1 event/day
AF
(Soil adherence factor)
= 0.2 mg/cm2
								(nonresidential)
AEd
(Dermal absorption efficiency)
= chemical-specific or default specified at R
								299.20(3)
(3)
				  Absorption efficiencies used to calculate generic direct contact criteria are
				  as follows:
(a) Chemical-specific data may be
				  submitted to the department to support development of a new generic criterion
				  under R 299.6(9) or (10) and shall be used in this rule if determined by the
				  department to be the best available information.
(b) If chemical-specific data are not
				  available, then the following default absorption efficiencies shall be used:
(i) AEi shall be 50%
				  for organic hazardous substances which exhibit a log octanol water partitioning
				  coefficient greater than 5 and a molecular weight greater than 200 grams per
				  mole or which are not ionizing organic compounds, and 100% for all other
				  organic hazardous substances.
(ii)
				  AEi shall be 50% for inorganic hazardous
				  substances.
(iii)
				  AEd shall be assumed to be 10% for organic hazardous
				  substances.
(iv)
				  AEd shall be assumed to be 1% for inorganic hazardous
				  substances.