NR 720.07 Note
Note: Averaging soil concentrations is not appropriate as the sole method for addressing sites with areas of significant soil contamination.
NR 720.07(2)(c)
(c) If a soil cleanup standard for a soil contaminant is between the limit of detection and the limit of quantitation, the soil cleanup standard shall be considered to be exceeded if the soil contaminant concentration is reported at or above the limit of quantitation.
NR 720.07(2)(d)
(d) The following applies when a soil cleanup standard for a soil contaminant is below the limit of detection:
NR 720.07(2)(d)1.
1. If a soil contaminant is not detected in a sample, the soil cleanup standard shall not be considered to have been exceeded.
NR 720.07(2)(d)2.
2. If a soil contaminant is reported above the limit of detection but below the limit of quantitation, the responsible party may accept the results and the soil cleanup standard shall be considered to have been exceeded, or the responsible party may choose to have the soil sample reanalyzed by the use of an appropriate analytical method. If the soil contaminant is confirmed to be present between the limit of detection and the limit of quantitation, the soil cleanup standard shall be considered to have been exceeded. If the soil contaminant is not detected upon reanalysis of the soil sample, the soil cleanup standard shall not be considered to have been exceeded.
NR 720.07(3)
(3) Background. If the background concentration for a substance in soil at a site or facility is higher than the residual contaminant level for that substance determined using the procedures in this section, the background concentration in soil may be used as the residual contaminant level for that substance. The background concentration for a substance in soil shall be determined using a department-approved and appropriate method.
NR 720.07 Note
Note: Naturally occurring background concentrations of arsenic in soil, for example, may be higher than the calculated residual contaminant level for arsenic. In such instances, the naturally occurring background concentration could be used as the soil cleanup level.
NR 720.07 History
History: Cr.
Register, March, 1995, No. 471, eff. 4-1-95;
CR 12-023: am. (title), (1) (a) to (c), cr. (1) (c) 4., am. (2) (b), (d) 2., cr. (3)
Register October 2013 No. 694, eff. 11-1-13.
NR 720.08
NR 720.08 Procedures for establishing soil performance standards. NR 720.08(1)(1)
General. If a responsible party selects this option, performance standards shall be established and maintained so that the residual contaminants in the soil do not pose a threat to public health, safety, or welfare or the environment.
NR 720.08 Note
Note: Guidance document RR-528 indicates that it may not be necessary to determine numeric residual contaminant levels for contaminants as long as all contaminant pathways for all contaminants of concern are addressed by the remedial action, the extent of contamination is fully defined, the remedy remains in place, is maintained as appropriate and remains effective. For example, if a cover is placed that addresses all pathways for the contaminated soil, then it isn't necessary to determine the numeric residual contaminant levels for as long as the cover adequately addresses the pathway and remains protective. It may be necessary to determine residual contaminant levels in the future if the remedy is changed or replaced.
NR 720.08(2)
(2) Protection of groundwater. Acceptable performance standard options to address the soil to groundwater pathway may include any of, or any combination of, the following:
NR 720.08(2)(a)
(a) Placement of a permanent engineering control such as a cap or cover to limit infiltration and thereby minimizing the leaching of soil contaminants to groundwater that is constructed and maintained until the threat to groundwater no longer exists.
NR 720.08(2)(b)
(b) Use of natural attenuation to contain and remediate the contaminants present.
NR 720.08(2)(c)
(c) Operation of a system in compliance with
ch. NR 724 until the lowest concentration that is practicable is achieved.
NR 720.08 Note
Note: As explained in more detail in guidance document RR-528, if there is no threat to groundwater from soil contamination, a soil remedy is not necessary. The lack of groundwater contamination may not always be sufficient to establish there is not threat to the groundwater pathway. An analysis to determine whether sufficient time has passed for the soil contamination to have reached the locations where groundwater is being monitored may be necessary. The factors that may need to be considered include: the age of the contaminant release, type of contaminants, geologic setting, depth to groundwater, and the proximity of the monitoring wells to the source of contamination.
NR 720.08(3)
(3) Protection from direct contact. Acceptable performance standard options to address the direct contact pathway may include either of, or a combination of, the following:
NR 720.08(3)(a)
(a) Placement of a permanent engineering control such as a cap or cover that is constructed and maintained until the direct contact threat no longer exists.
NR 720.08(3)(b)
(b) Operation of a system in compliance with
ch. NR 724 until the lowest concentration that is practicable is achieved.
NR 720.08 History
History: CR 12-023: cr.
Register October 2013 No. 694, eff. 11-1-13.
NR 720.10
NR 720.10 Procedures for determining residual contaminant levels based on protection of groundwater. NR 720.10(1)(1)
General. If a responsible party selects this option, residual contaminant levels for soil based on protection of groundwater shall be developed using the enforcement standards established in
ch. NR 140 or using procedures consistent with the methodology in ss.
160.13 and
160.15, Stats., and the criteria in
s. NR 722.09 (2) (b) 2. when there is no enforcement standard as the target concentrations in groundwater. If the department of health has not developed a recommended enforcement standard and a federal maximum contaminant level exists, that value may be used for calculating a soil residual contaminant level.
NR 720.10 Note
Note: In developing a residual contaminant level, any relevant information may be considered, including public welfare concerns for groundwater, such as taste and odor, and drinking water health advisory levels.
NR 720.10(2)
(2) Methods. Responsible parties shall use one or more of the methods listed in this section based on scientifically valid procedures that are subject to department review and approval and site-specific geological, physical and chemical conditions to establish residual contaminant levels:
NR 720.10(2)(b)
(b) Leaching tests appropriate for the site or facility in both application and extent.
NR 720.10(2)(c)
(c) Any other appropriate method approved by the department for that specific site or facility, or other appropriate method suggested in department guidance.
NR 720.10 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 groundwater quality. 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 720.10 History
History: CR 12-023: cr.
Register October 2013 No. 694, eff. 11-1-13.
NR 720.12
NR 720.12 Procedures for determining residual contaminant levels based on protection of human health from direct contact with contaminated soil. NR 720.12(1)(1)
General. If a responsible party selects this option, residual contaminant levels for soil based on protection of human health from direct contact shall be developed using the following criteria:
NR 720.12(1)(a)
(a) For individual compounds using an excess cancer risk of 1x10
-6 and a hazard quotient for non-carcinogens of one; and
NR 720.12(1)(b)
(b) The cumulative excess cancer risk will not exceed 1x10
-5 and the hazard index for non-carcinogens will not exceed one for the site or facility.
NR 720.12(1)(c)
(c) Risks for carcinogens and hazard quotients for non-carcinogens are presumed to be additive within each category, unless there is specific information that demonstrates that an alternative approach is more appropriate.
NR 720.12(1)(d)
(d) If toxicological values for both carcinogenic and non-carcinogenic end points exist for a substance, both shall be evaluated and the method that generates the lowest residual contaminant level shall be used for the site or facility.
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.
