NR 720.12(2)
(2) Methods and procedures. Responsible parties shall determine a residual contaminant level to protect public health from direct contact with soil contamination using scientifically valid procedures and toxicological values approved by the department and the default exposure assumptions identified in
sub. (3) or alternative assumptions specifically approved by the department in writing.
NR 720.12 Note
Note: The department will generally consider toxicological values in the following order: U.S. EPA's Integrated Risk Information System (IRIS); U.S. EPA's Provisional Peer Reviewed Toxicity Values (PPRTV); Agency for Toxic Substances and Disease Registry (ATSDR); California EPA (Cal EPA); U.S. EPA's Health Effects Assessment Summary Tables (HEAST); other pertinent toxicological information.
NR 720.12(3)(a)(a)
Non-carcinogens. When the contaminant is not a carcinogen, the following default exposure assumptions shall be used:
NR 720.12(3)(a)1.
1. When the land use of a site or facility is classified as non-industrial, in accordance with
s. NR 720.05 (5), all of the following shall apply:
NR 720.12(3)(a)1.a.
a. Incidental ingestion of soil shall be assumed to occur at the rate of 200 mg of soil per day for a 15 kg child for 350 days each year.
NR 720.12(3)(a)1.b.
b. Dermal absorption of soil shall be determined assuming a child's daily exposed skin surface area of 2,800 cm
2 with a skin-soil adherence factor of 0.2 mg/cm
2 and a contaminant specific dermal absorption fraction.
NR 720.12(3)(a)1.c.
c. Inhalation of outdoor soil vapors shall be assumed to occur for each volatile contaminant at a 24-hour daily exposure rate determined by the volatile's soil-to-air volatilization factor, and inhalation of particulate matter shall be determined assuming a particulate emission factor of 1.43 x10
9 m
3/kg.
NR 720.12(3)(a)1.d.
d. An averaging period for exposure shall equal the default exposure duration of 6 years.
NR 720.12(3)(a)2.
2. When the land use of a site or facility is classified as industrial, in accordance with
s. NR 720.05 (5), all of the following shall apply:
NR 720.12(3)(a)2.a.
a. Incidental ingestion of soil shall be assumed to occur at the rate of 100 mg of soil per day for a 70 kg adult worker for 250 days each year.
NR 720.12(3)(a)2.b.
b. Dermal absorption of soil shall be determined assuming an adult outdoor worker's daily exposed skin surface of 3,300 cm
2 with a skin-soil adherence factor of 0.2 mg/cm
2 and a contaminant specific dermal absorption fraction.
NR 720.12(3)(a)2.c.
c. Inhalation of outdoor soil vapors shall be assumed to occur for each volatile contaminant at an 8-hour daily exposure rate determined by the volatile contaminant's soil-to-air volatilization factor, and inhalation of particulate matter shall be determined assuming a particulate emission factor of 1.43 x10
9 m
3/kg.
NR 720.12(3)(a)2.d.
d. An averaging period of exposure shall equal the default exposure duration of 25 years.
NR 720.12(3)(b)
(b)
Carcinogens. When the contaminant is a carcinogen, the following default exposure assumptions shall be used:
NR 720.12(3)(b)1.
1. When the land use of a site or facility is classified as non-industrial, in accordance with
s. NR 720.05 (5), all of the following shall apply:
NR 720.12(3)(b)1.a.
a. Incidental ingestion of soil shall be assumed to occur at the rate of 200 mg of soil per day for 350 days each year for 6 years for a 15 kg child and the rate of 100 mg per day for 350 days each year for 24 years for a 70 kg adult.
NR 720.12(3)(b)1.b.
b. Dermal absorption of soil shall be determined assuming a child's daily exposed skin surface area of 2,800 cm
2 with a skin-soil adherence factor of 0.2 mg/cm
2, and an adult's daily exposed skin-surface area of 5,700 cm
2 with a skin-soil adherence factor of 0.07 mg/cm
2 and a contaminant specific dermal absorption fraction.
NR 720.12(3)(b)1.c.
c. Inhalation of outdoor soil vapors shall be assumed to occur for each volatile contaminant at a 24-hour daily exposure rate determined by the volatile contaminant's soil-to-air volatilization factor, and inhalation of particulate matter shall be determined assuming a particulate emission factor of 1.43 x10
9 m
3/kg. For mutagenic contaminants, age segmented exposure durations shall be assumed when age adjusted cancer slope factors are available.
NR 720.12(3)(b)1.d.
d. An averaging period of 30 years of exposure consisting of 6 child years and 24 adult years shall be assumed during a 70 year lifetime.
NR 720.12(3)(b)2.
2. When the land use of a site or facility is classified as industrial, in accordance with
s. NR 720.05 (5), all of the following shall apply:
NR 720.12(3)(b)2.a.
a. Incidental ingestion of soil shall be assumed to occur at the rate of 100 mg of soil per day for 250 days each year for a 70 kg adult worker.
NR 720.12(3)(b)2.b.
b. Dermal absorption of soil shall be determined assuming an adult outdoor worker's daily exposed skin surface of 3,300 cm
2 with a skin-soil adherence factor of 0.2 mg/cm
2 and a contaminant specific dermal absorption fraction.
NR 720.12(3)(b)2.c.
c. Inhalation of outdoor soil vapors shall be assumed to occur for each volatile contaminant at an 8-hour daily exposure rate determined by the volatile contaminant's soil-to-air volatilization factor, and inhalation of particulate matter shall be determined assuming a particulate emission factor of 1.43 x10
9 m
3/kg.
NR 720.12(3)(b)2.d.
d. An averaging period of 25 years of exposure shall be assumed during a 70 year lifetime.
NR 720.12 Note
Note: Department approval of alternative exposure assumptions for a site or facility may be based on consultation with the department of health services. If EPA makes changes to the default exposure assumptions, the department would generally use the revised values.
NR 720.12 Note
Note: Guidance document RR-890 provides detailed instructions on one method the department considers scientifically valid for purposes of calculating site specific residual contaminant levels that are protective of the direct contact pathway. A table of residual contaminant levels that are calculated using the standard default exposure assumptions can be found at:
http://dnr.wi.gov/topic/Brownfields/professionals.html#tabx2.
NR 720.12(4)
(4) Soil parameter values. Unless otherwise approved, when determining site specific residual contaminant levels, all the following soil parameter values shall be used:
NR 720.12 Note
Note: These soil parameter values are the defaults used in Pub-RR-890, “Soil Residual Contaminant Level Determination Using the US EPA Regional Screening Level Web Calculator." This guidance may be found at
http://dnr.wi.gov/topic/Brownfields/Pubs.html.
NR 720.12 History
History: CR 12-023: cr.
Register October 2013 No. 694, eff. 11-1-13.
NR 720.13
NR 720.13
Other pathways of concern. Responsible parties shall consider human food chain, surface water quality, and terrestrial eco-system pathways of exposure, when those pathways of exposure are of concern at a site or facility.
NR 720.13 Note
Note: In some cases, the potential for contaminant migration or exposure to contamination through other pathways may be of concern at a site or facility. These situations could include contaminated soil in close proximity to a surface water where the potential for runoff from the site or facility to cause an impact on surface water quality exists or contaminated soil where potential for bioaccumulation and uptake through the food chain resulting in adverse impacts to human health or terrestrial ecosystems exists. This section requires responsible parties to establish appropriate residual contaminant levels protective of these pathways when necessary.
NR 720.13 History
History: CR 12-023: cr.
Register October 2013 No. 694, eff. 11-1-13.
