Register November 2013 No. 695
Chapter NR 720
SOIL CLEANUP STANDARDS
NR 720.07 General requirements when establishing soil cleanup standards applicable to a site or facility.
NR 720.08 Procedures for establishing soil performance standards.
NR 720.10 Procedures for determining residual contaminant levels based on protection of groundwater.
NR 720.12 Procedures for determining residual contaminant levels based on protection of human health from direct contact with contaminated soil.
NR 720.13 Other pathways of concern.
NR 720.01
NR 720.01
Purpose. The purpose of this chapter is to establish soil cleanup standards, for the remediation of soil contamination, which result in restoration of the environment to the extent practicable, minimize harmful effects to the air, lands and waters of the state and are protective of public health, safety, and welfare and the environment as required by
ch. 292, Stats., and which are consistent with
ch. 160, Stats., and
ch. NR 140. This chapter is adopted pursuant to ss.
227.11 (2) and
289.06 (1) and
(2), Stats., and
ch. 292, Stats.
NR 720.01 History
History: Cr.
Register, March, 1995, No. 471, eff. 4-1-95; am.,
Register, February, 1996, No. 482, eff. 3-1-96;
CR 12-023: am.
Register October 2013 No. 694, eff. 11-1-13.
NR 720.02(1)(1) This chapter applies to all remedial actions taken by responsible parties to address soil contamination after an investigation has been conducted at a site, facility or portion of a site or facility that is subject to regulation under
ch. 292, Stats., regardless of whether there is direct involvement or oversight by the department. This chapter also applies to soil contamination at all of the following:
NR 720.02(1)(a)
(a) Solid waste facilities, where remedial action is required by the department pursuant to
ch. NR 508.
NR 720.02 Note
Note: Chapter
NR 720 does not apply to landspreading regulated under ch.
NR 518 or solid waste facilities where ongoing operations are occurring, unless remedial action is required pursuant to ch.
NR 508.
NR 720.02(1)(b)
(b) Hazardous waste facilities, where the owner or operator is required to close the facility pursuant to s.
291.29, Stats., or subchs.
G and
H of ch. NR 664, or to institute corrective action pursuant to s.
291.37, Stats., or
s. NR 664.0100. However, if U.S. EPA requires that states employ soil cleanup standards for hazardous waste facilities that are more stringent than the standards in this chapter, the department is obligated under the state's hazardous waste management act,
ch. 291, Stats., and its hazardous waste program RCRA authorization to apply the more stringent soil cleanup standards.
NR 720.02 Note
Note: Section NR 600.07 no longer exists.
NR 720.02 Note
Note: Chapter
NR 720 applies to abandonment of lagoons, storage structures and treatment structures for sewage treatment facilities projects; abandonment of lagoons, storage structures and treatment structures that receive wastewaters, associated sludges, by-product solids and any resulting leachates from industrial, commercial or agricultural sources, except as provided in s.
NR 213.02 (2); and abandonment of land treatment systems for industrial liquid wastes, by-product solids and sludges, except as provided in s.
NR 214.02 (3). Chapter
NR 720 does not apply to activities regulated under s.
281.48, Stats., or permitted activities regulated under
40 CFR 503 or ch.
NR 204,
206 or
214, including permitted land spreading of sludge or land disposal of wastewaters from municipal and domestic wastewater treatment works and permitted land treatment of industrial liquid wastes, by-product solids and sludges.
NR 720.02(1)(d)
(d) Sites where remedial action is being taken by a person who is seeking the liability exemption under
s. 292.15, Stats.
NR 720.02 Note
Note: U.S. EPA has independent authority to regulate soil contamination from PCB's under the toxic substances control act. The department and EPA have entered into an MOA that specifies how responsibility for these types of sites will be determined. The MOA can be found at:
http://dnr.wi.gov/files/pdf/pubs/rr/rr786.pdf.
NR 720.02(2)
(2) This chapter applies to interim actions taken by responsible parties or other persons under s.
292.15, Stats., when at the completion of both the site investigation and interim action taken to address contaminated soil, the responsible parties or persons taking action under s.
292.15, Stats., request that the site or facility be closed out in accordance with
ch. NR 726, without taking a subsequent remedial action to address the contaminated soil.
NR 720.02(3)
(3) This chapter applies to remedial actions taken by the department where a department-funded response action is being taken under the authority of
ch. 292, Stats.
NR 720.02(4)
(4) Concentrations of legally applied pesticides are exempt from the requirements of this chapter when all of the following conditions are met:
NR 720.02(4)(a)
(a) The application of the pesticide was done in compliance with:
NR 720.02(4)(b)
(b) For pesticides that are intended to be applied to the soil, pesticide concentrations exceeding soil cleanup standards are only found in the surface soil layer, where the pesticide is expected to perform its intended purpose, and only at concentrations that would be expected from pesticide application, in compliance with the pesticide label requirements.
NR 720.02 Note
Note: The depth of the surface layer of soil will vary depending on the type of pesticide applied and the appropriate intended use of that pesticide.
NR 720.02(5)
(5) The department may exercise enforcement discretion on a case-by-case basis and choose to regulate a site, facility or a portion of a site or facility under only one of a number of potentially applicable statutory authorities. However, where overlapping restrictions or requirements apply, the more restrictive control. The department shall, after receipt of a request from a responsible party, provide a letter that indicates which regulatory program or programs the department considers to be applicable.
NR 720.02 Note
Note: Sites, facilities or portions of a site or facility that are subject to regulation under ch.
292, Stats., may also be subject to regulation under other statutes, including solid waste statutes, ch.
289, Stats., or the hazardous waste management act, ch.
291, Stats., and the administrative rules adopted pursuant to those statutes. One portion of a site or facility may be regulated under a different statutory authority than other portions of that site or facility. When necessary, the department will, to the best of its ability, facilitate coordination between the regulatory programs involved.
NR 720.02(6)
(6) The department may take any action within the context of regulatory programs established in statutes or rules outside this chapter, if those actions are necessary to protect public health, welfare, or safety or prevent a damaging effect on the environment for present and future uses, whether or not a soil cleanup standard has been adopted under this chapter.
NR 720.02(7)
(7) Nothing in this chapter authorizes an impact on soil quality that would cause a violation of a groundwater quality standard contained in
ch. NR 140, an impact on soil quality or groundwater quality that would cause a violation of a surface water quality standard contained in
chs. NR 102 to
106 or an impact on soil quality that would cause a violation of an air quality standard contained in
chs. NR 400 to
499.
NR 720.02 History
History: Cr.
Register, March, 1995, No. 471, eff. 4-1-95; cr. (1) (d), am. (2);
Register, February, 1996, No. 482, eff. 3-1-96; emerg. am. (1) (intro.), cr. (1m), eff. 5-18-00; am. (1) (intro.), cr. (1m),
Register, January, 2001, No. 541, eff. 2-1-01; corrections in (1) (b) made under s. 13.93 (2m) (b) 7., Stats.,
Register September 2007 No. 621;
CR 12-023: am. (1) (intro.), (a), (b), cr. (1) (e), r. (1m), am. (3),
Register October 2013 No. 694, eff. 11-1-13.
NR 720.03
NR 720.03
Definitions. In this chapter:
NR 720.03(1)
(1) “Aquifer" means a saturated subsurface geological formation of rock or soil.
NR 720.03(1m)
(1m) “Ceiling limit concentration" means a preset non-risk based concentration of an inorganic or semi-volatile chemical.
NR 720.03 Note
Note: This definition is consistent with the approach used in the U.S. EPA's Regional Screening Table which sets a ceiling limit concentration of 100,000 mg/kg or 10% by weight for a relatively non-toxic chemical in a soil sample. This definition is not the same as in other natural resources administrative rules. For example, the term ceiling limit in ch.
NR 204 refers to the concentration of certain metals in domestic sludge that if exceeded would result in the sludge not being eligible for land application.
NR 720.03(2)
(2) “Contaminant of concern" means a hazardous substance that is present at a site or facility in such concentrations that the contaminant poses an actual or potential threat to human health, safety, or welfare or the environment based upon:
NR 720.03(2)(a)
(a) The toxicological characteristics of the hazardous substance that influence its ability to adversely affect human health or the environment relative to the concentration of the hazardous substance at the site or facility;
NR 720.03(2)(b)
(b) The chemical and physical characteristics of the hazardous substance which govern its tendency to persist in the environment and the chemical, physical and biological characteristics at the site or facility which govern the tendency for the hazardous substance to persist at the site or facility;
NR 720.03(2)(c)
(c) The chemical and physical characteristics of the hazardous substance which govern its tendency to move into and through environmental media;
NR 720.03(2)(d)
(d) The naturally occurring background concentrations of the hazardous substance;
NR 720.03(2)(e)
(e) The thoroughness of the testing for the hazardous substance at the site or facility;
NR 720.03(2)(f)
(f) The frequency that the hazardous substance has been detected at the site or facility; and
NR 720.03(3)
(3) “Cumulative excess cancer risk" means the upper bound on the estimated excess cancer risk associated with exposure to multiple hazardous substances or multiple exposure pathways.
NR 720.03(3m)
(3m) “Dermal absorption" means systemic exposure via skin absorption. However, because dermal toxicity factors are not available, oral-to-dermal extrapolation is done by adjusting for gastrointestinal absorption in order to derive toxicity values in terms of a dermally-absorbed dose.
NR 720.03 Note
Note: Dermal toxicity values that are extrapolated from oral toxicity values may not take into account allergic contact responses or skin cancer.
NR 720.03(4)
(4) “Direct contact" means human exposure to substances in soil through one or more of the following pathways: inhalation of particulate matter,
dermal absorption, incidental ingestion, or inhalation of vapors from the soil.
NR 720.03(5)
(5) “Hazard index" means the sum of 2 or more hazard quotients for multiple hazardous substances or multiple exposure pathways.
NR 720.03(6)
(6) “Hazard quotient" means the ratio of the exposure of a single hazardous substance over a specified time period to a reference dose, or reference concentration where appropriate, for that hazardous substance derived for a similar exposure period.
NR 720.03 Note
Note: Hazard quotients and hazard indices are measures of the potential for noncarcinogenic effects.
NR 720.03(7)
(7) “Incidental ingestion of soil" means ingestion of soil by humans as a result of normal hand-to-mouth behaviors.
NR 720.03(8)
(8) “Inhalation of particulate matter" means inhalation by humans of contaminants adsorbed to respirable soil particles less than 10 microns in diameter.
NR 720.03(9m)
(9m) “Inhalation of vapors" means inhalation by humans of soil contaminants that volatilized into outdoor air.
NR 720.03(11)
(11) “Pathway" means the route a substance takes in traveling to a receptor or potential receptor or the specific portal of entry, such as lungs, skin or digestive tract, the substance takes to potentially express its toxic effect, or both.
NR 720.03 Note
Note: An example of the food chain pathway is when a substance is taken up from soil to plant tissue and the plant tissue is then ingested by a person.
NR 720.03(12m)
(12m) “Performance standard" means a remedial action or, in some cases existing site conditions that prevent exposure to contaminants or will result in a decrease in contaminant concentrations, or both.
NR 720.03(13)
(13) “Restricted access areas" means land immediately adjacent to highways or railroad right-of-ways, where the presence of structural controls, such as fencing, has eliminated pedestrian ingress by the public.
NR 720.03(14)
(14) “Risk" means the probability that a hazardous substance, when released to the environment, will cause carcinogenic effects in exposed humans or other biological receptors.
NR 720.03(15)
(15) “Soil cleanup standard" means either a residual contaminant level determined in accordance with
ss. NR 720.10 or
720.12, or a soil performance standard determined in accordance with
s. NR 720.08.
NR 720.03(16)
(16) “Soil saturation concentration" or “Csat" means the contaminant concentration in soil at which the absorptive limits of the soil particles, the solubility limits of the soil particles, the solubility limits of the soil pore-water, and saturation of soil pore-air have been reached. At concentrations greater than Csat, the soil contaminant may be present in free phase for contaminants that are liquid at ambient soil temperatures and pure solid phases for compounds that are solid at ambient soil temperatures.
NR 720.03 History
History: Cr.
Register, March, 1995, No. 471, eff. 4-1-95; corrections in (12) (c) made under s. 13.93 (2m) (b) 7., Stats.,
Register September 2007 No. 621;
CR 12-023: cr. (1m), (3m), am. (4), (8), r. (9), cr. (9m), r. (10), (12), cr. (12m), am. (14), cr. (15), (16)
Register October 2013 No. 694, eff. 11-1-13.
NR 720.05(1)(1)
Remedial action. Responsible parties shall select and implement a remedial action to address soil contamination when, after any of the following investigations has been completed, information collected during the investigation indicates that a remedial action to address soil contamination is necessary to achieve compliance with the requirements of this chapter:
NR 720.05(1)(b)
(b) Solid waste site investigation report prepared in accordance with the requirements of
ch. NR 508.
NR 720.05(1)(c)
(c) Investigation done under a hazardous waste closure plan or a RCRA facility investigation report, developed in accordance with the requirements of subchs.
G and
H of ch. NR 664 or
s. NR 664.0100.
NR 720.05 Note
Note: Remedial actions at some types of sites or facilities, such as the abandonment of wastewater lagoons, may only have to comply with ch.
NR 720 and not other requirements in the NR 700 series, such as the minimum site investigation requirements in ch.
NR 716. In this case, the department or responsible parties may choose to use the other chapters of the NR 700 rule series as guidance for complying with ch.
NR 720.
