Chapter NR 668

Subchapter D — Treatment Standards

NR 668.40   Applicability of treatment standards.

NR 668.41   Treatment standards expressed as concentrations in waste extract.

NR 668.42   Treatment standards expressed as specified technologies.

NR 668.43   Treatment standards expressed as waste concentrations.

NR 668.44   Variance from a treatment standard.

NR 668.45   Treatment standards for hazardous debris.

NR 668.46   Alternative treatment standards based on HTMR.

NR 668.48   Universal treatment standards.

NR 668.49   Alternative LDR treatment standards for contaminated soil.

Subchapter E — Prohibitions on Storage

NR 668.50   Prohibitions on storage of restricted wastes.

Ch. NR 668 Note Note: This chapter is similar to federal regulations contained in 40 CFR part 268, revised as of July 1, 2003.

subch. A of ch. NR 668 Subchapter A — General

NR 668.01 NR 668.01 Purpose, scope and applicability.

NR 668.01(1) (1) This chapter identifies hazardous wastes that are restricted from land disposal and defines those limited circumstances under which an otherwise prohibited waste may continue to be land disposed.

NR 668.01(2) (2) Except as specifically provided otherwise in this chapter or ch. NR 661, the requirements of this chapter apply to persons who generate or transport hazardous waste and owners and operators of hazardous waste treatment, storage and disposal facilities.

NR 668.01(3) (3) Restricted wastes may continue to be land disposed if any of the following conditions are met:

NR 668.01(3)(a) (a) The EPA administrator has granted an extension to the effective date of a prohibition under 40 CFR 268.5 with respect to those wastes covered by the extension.

NR 668.01(3)(b) (b) The EPA administrator has granted an exemption from a prohibition pursuant to a petition under 40 CFR 268.6, with respect to those wastes and units covered by the petition.

NR 668.01(3)(c) (c) Wastes that are hazardous only because they exhibit a hazardous characteristic, and which are otherwise prohibited under this chapter or 40 CFR part 148 are not prohibited if the wastes meet all of the following:

NR 668.01(3)(c)1. 1. The wastes are disposed into a nonhazardous or hazardous injection well as defined under 40 CFR 146.6 (a).

NR 668.01(3)(c)2. 2. The wastes at the point of injection do not exhibit any prohibited characteristic of hazardous waste as identified in subch. C of ch. NR 661.

NR 668.01(3)(d) (d) The wastes are hazardous only because they exhibit a hazardous characteristic, unless the wastes are subject to a specified method of treatment other than DEACT in s. NR 668.40, or are D003 reactive cyanide and the wastes meet subds. 1. or 2. or 3. and subd. 4.

NR 668.01(3)(d)1. 1. The wastes are managed in a treatment system which subsequently discharges to waters of the state pursuant to a permit issued under ch. 283, Stats.

NR 668.01(3)(d)2. 2. The wastes are treated for purposes of the pretreatment requirements of ch. 283, Stats.

NR 668.01(3)(d)3. 3. The wastes are managed in a zero discharge system engaged in CWA-equivalent treatment as defined in s. NR 668.37.

NR 668.01(3)(d)4. 4. The wastes no longer exhibit a prohibited characteristic at the point of land disposal (i.e., placement in a surface impoundment).

NR 668.01(4) (4) The requirements of this chapter may not affect the availability of a waiver under 42 USC 9621 (d) (4).

NR 668.01(5) (5) All of the following hazardous wastes are not subject to this chapter:

NR 668.01(5)(a) (a) Waste generated by very small quantity generators, as defined in s. NR 660.10 (139).

NR 668.01(5)(b) (b) Waste pesticides that a farmer disposes of pursuant to s. NR 662.070.

NR 668.01(5)(c) (c) Wastes identified or listed as hazardous after November 8, 1984 for which EPA has not promulgated land disposal prohibitions or treatment standards.

NR 668.01(5)(d) (d) De minimis losses of characteristic wastes to wastewaters are not considered to be prohibited wastes and are defined as losses from normal material handling operations (e.g., spills from the unloading or transfer of materials from bins or other containers, leaks from pipes, valves or other devices used to transfer materials). The following are also considered to be de minimus losses: minor leaks of process equipment, storage tanks or containers; leaks from well-maintained pump packings and seals; sample purgings; and relief device discharges; discharges from safety showers and rinsing and cleaning of personal safety equipment; rinsate from empty containers or from containers that are rendered empty by that rinsing; and laboratory wastes not exceeding one % of the total flow of wastewater into the facility’s headworks on an annual basis, or with a combined annualized average concentration not exceeding one part per million in the headworks of the facility’s wastewater treatment or pretreatment facility.

NR 668.01(6) (6) Universal waste handlers and universal waste transporters, as defined in s. NR 660.10, are exempt from ss. NR 668.07 and 668.50 for all of the following hazardous wastes.

NR 668.01(6)(a) (a) Batteries as described in s. NR 673.02.

NR 668.01(6)(b) (b) Pesticides as described in s. NR 673.03.

NR 668.01(6)(c) (c) Mercury-containing equipment as described in s. NR 673.04.

NR 668.01(6)(d) (d) Lamps as described in s. NR 673.05.

NR 668.01 History History: CR 05-032: cr. Register July 2006 No. 607, eff. 8-1-06; CR 16-007: am. (6) (c) Register July 2017 No. 739, eff. 8-1-17; CR 19-082: cr. (3) (c), r. and recr. (5) (a) Register August 2020 No. 776, eff. 9-1-20; correction in (3) (c) (intro.), 1. made under s. 35.17, Stats., Register August 2020 No. 776.

NR 668.02 NR 668.02 Definitions applicable in this chapter. When used in this chapter the following terms have the meanings given below:

NR 668.02(1) (1) “Halogenated organic compounds” or “HOCs” means those compounds having a carbon-halogen bond which are listed under ch. NR 668 Appendix III.

NR 668.02(2) (2) “Hazardous constituent” or “hazardous constituents” means those constituents listed in ch. NR 661 Appendix VIII.

NR 668.02(3) (3) “Land disposal” means placement in or on the land, except in a corrective action management unit or staging pile, and includes, but is not limited to, placement in a landfill, surface impoundment, waste pile, injection well, salt dome formation, salt bed formation, underground mine or cave, or placement in a concrete vault, or bunker intended for disposal purposes.

NR 668.02(4) (4) “Nonwastewaters” means wastes that do not meet the criteria for wastewaters in s. NR 668.02 (6).

NR 668.02(5) (5) “Polychlorinated biphenyls” or “PCBs” means halogenated organic compounds defined in accordance with 40 CFR 761.3.

NR 668.02(6) (6) “Wastewaters” means wastes that contain less than one % by weight total organic carbon (TOC) and less than one% by weight total suspended solids (TSS).

NR 668.02(7) (7) “Debris” means solid material exceeding a 60 mm particle size that is intended for disposal and that is a manufactured object; or plant or animal matter; or natural geologic material. However, the following materials are not debris: any material for which a specific treatment standard is provided in subch. D, namely lead acid batteries, cadmium batteries, and radioactive lead solids; process residuals such as smelter slag and residues from the treatment of waste, wastewater, sludges, or air emission residues; and intact containers of hazardous waste that are not ruptured and that retain at least 75% of their original volume. A mixture of debris that has not been treated to the standards provided by s. NR 668.45 and other material is regulated as debris if the mixture is comprised primarily of debris, by volume, based on visual inspection.

NR 668.02(8) (8) “Hazardous debris” means debris that contains a hazardous waste listed in subch. D of ch. NR 661, or that exhibits a characteristic of hazardous waste identified in subch. C of ch. NR 661. Any deliberate mixing of prohibited hazardous waste with debris that changes its treatment classification, for example, from waste to hazardous debris, is not allowed under the dilution prohibition in s. NR 668.03.

NR 668.02(9) (9) “Underlying hazardous constituent” means any constituent listed in s. NR 668.48, Table UTS—Universal Treatment Standards, except fluoride, selenium, sulfides, vanadium, and zinc, which can reasonably be expected to be present at the point of generation of the hazardous waste at a concentration above the constituent-specific UTS treatment standards.

NR 668.02(10) (10) “Inorganic metal-bearing waste” means waste for which EPA has established treatment standards for metal hazardous constituents, and which does not otherwise contain significant organic or cyanide content as described in s. NR 668.03 (3) (a), and is specifically listed in ch. NR 668 Appendix XI.

NR 668.02(11) (11) “Soil” means unconsolidated earth material composing the superficial geologic strata (material overlying bedrock), consisting of clay, silt, sand, or gravel size particles as classified by the U.S. natural resources conservation service, or a mixture of such materials with liquids, sludges or solids which is inseparable by simple mechanical removal processes and is made up primarily of soil by volume based on visual inspection. Any deliberate mixing of prohibited hazardous waste with soil that changes its treatment classification, for example, from waste to contaminated soil, is not allowed under the dilution prohibition in s. NR 668.03.

NR 668.02 History History: CR 05-032: cr. Register July 2006 No. 607, eff. 8-1-06.

NR 668.03 NR 668.03 Dilution prohibited as a substitute for treatment.

NR 668.03(1) (1) Except as provided in sub. (2), no generator, transporter, handler, or owner or operator of a treatment, storage, or disposal facility may in any way dilute a restricted waste or the residual from treatment of a restricted waste as a substitute for adequate treatment to achieve compliance with subch. D, to circumvent the effective date of a prohibition in subch. C, to otherwise avoid a prohibition in subch. C, or to circumvent a land disposal prohibition imposed by 42 USC 6924.

NR 668.03(2) (2) Dilution of wastes that are hazardous only because they exhibit a characteristic in treatment systems which include land-based units which treat wastes subsequently discharged to a water of the State pursuant to a permit issued under section s. 283.31, Stats., or which treat wastes in a CWA-equivalent treatment system, or which treat wastes for the purposes of pretreatment requirements under ss. 283.11 and 283.21, Stats., is not impermissible dilution for purposes of this section unless a method other than DEACT has been specified in s. NR 668.40 as the treatment standard, or unless the waste is a D003 reactive cyanide wastewater or nonwastewater.

NR 668.03(3) (3) Combustion of the hazardous waste codes listed in ch. NR 668 Appendix XI is prohibited, unless the waste, at the point of generation, or after any bona fide treatment such as cyanide destruction prior to combustion, complies with one or more of the criteria in pars. (a) to (f), and is not otherwise specifically prohibited from combustion:

NR 668.03(3)(a) (a) The waste contains hazardous organic constituents or cyanide at levels exceeding the constituent-specific treatment standard found in s. NR 668.48.

NR 668.03(3)(b) (b) The waste consists of organic, debris-like materials, for example, wood, paper, plastic, or cloth, contaminated with an inorganic metal-bearing hazardous waste.

NR 668.03(3)(c) (c) The waste, at point of generation, has reasonable heating value, for example, greater than or equal to 5000 BTU per pound.

NR 668.03(3)(d) (d) The waste is co-generated with wastes for which combustion is a required method of treatment.

NR 668.03(3)(e) (e) The waste is subject to federal or Wisconsin requirements necessitating reduction of organics, including biological agents.

NR 668.03(3)(f) (f) The waste contains greater than one% total organic carbon (TOC).

NR 668.03(4) (4) Persons may not add iron filings or other metallic forms of iron to lead-containing hazardous wastes in order to achieve any land disposal restriction treatment standard for lead. Lead-containing wastes include all of the following:

NR 668.03(4)(a) (a) D008 wastes which exhibit a characteristic due to the presence of lead.

NR 668.03(4)(b) (b) All characteristic wastes containing lead as an underlying hazardous constituent.

NR 668.03(4)(c) (c) Listed wastes containing lead as a regulated constituent.

NR 668.03(4)(d) (d) Hazardous media containing any of the lead-containing wastes in this subsection.

NR 668.03 History History: CR 05-032: cr. Register July 2006 No. 607, eff. 8-1-06.

NR 668.04 NR 668.04 Treatment surface impoundment exemption.

NR 668.04(1) (1) Wastes which are otherwise prohibited from land disposal under this chapter, may be treated in a surface impoundment or series of impoundments if all of the following conditions are met:

NR 668.04(1)(a) (a) Treatment of the wastes occurs in the impoundments.

NR 668.04(1)(b) (b) All of the following conditions are met:

NR 668.04(1)(b)1. 1. Sampling and testing. For wastes with treatment standards in subch. D of ch. NR 668 or prohibition levels in subch. C, or both, or treatment standards in 42 USC 6924(d), the residues from treatment are analyzed, as specified in s. NR 668.07 or 668.32, to determine if they meet the applicable treatment standards or where no treatment standards have been established for the waste, the applicable prohibition levels. The sampling method, specified in the waste analysis plan under s. NR 664.0013 or 665.0013, shall be designed such that representative samples of the sludge and the supernatant are tested separately rather than mixed to form homogeneous samples.

NR 668.04(1)(b)2. 2. Removal. All of the following treatment residues, including any liquid waste, shall be removed at least annually: residues which do not meet the treatment standards promulgated under subch. D; residues which do not meet the prohibition levels established under subch. C or imposed by statute, where no treatment standards have been established; residues from the treatment of wastes prohibited from land disposal under subch. C, where no treatment standards have been established and no prohibition levels apply; or residues from managing listed wastes which are not delisted under 40 CFR 260.22. If the volume of liquid flowing through the impoundment or series of impoundments annually is greater than the volume of the impoundment or impoundments, this flow-through constitutes removal of the supernatant for the purpose of this requirement.

NR 668.04(1)(b)3. 3. Subsequent management. Treatment residues may not be placed in any other surface impoundment for subsequent management.

NR 668.04(1)(b)4. 4. Recordkeeping. Sampling and testing and recordkeeping provisions of ss. NR 664.0013 and 665.0013 apply.

NR 668.04(1)(c) (c) The impoundment meets the design requirements of s. NR 664.0221 (3) or 665.0221 (1), regardless that the unit may not be new, expanded, or a replacement, and the impoundment is in compliance with applicable groundwater monitoring requirements of ch. NR 664 unless one of the following conditions are met:

NR 668.04(1)(c)1. 1. The surface impoundment is exempted pursuant to s. NR 664.0221 (4) or (5), or pursuant to s. NR 665.0221 (3) or (4).

NR 668.04(1)(c)2. 2. Upon application by the owner or operator, the department, after notice and an opportunity to comment, grants a waiver of the design requirements on the basis that the surface impoundment meets all of the following conditions:

NR 668.04(1)(c)2.a. a. The surface impoundment has at least one liner, and there is no evidence that the liner is leaking.

NR 668.04(1)(c)2.b. b. The surface impoundment is located more than one-quarter mile from an underground source of drinking water.

NR 668.04(1)(c)2.c. c. The surface impoundment is in compliance with generally applicable groundwater monitoring requirements for facilities with licenses.

NR 668.04(1)(c)3. 3. Upon application by the owner or operator, the department, after notice and an opportunity to comment, grants a modification to the design requirements on the basis of a demonstration that the surface impoundment is located, designed and operated so as to assure that there will be no migration of any hazardous constituent into groundwater or surface water at any future time.

NR 668.04(1)(d) (d) The owner or operator submits to the department a written certification that the requirements of par. (c) have been met. The following certification is required:

I certify under penalty of law that the requirements of s. NR 668.04 (1) (c) have been met for all surface impoundments being used to treat restricted wastes. I believe that the submitted information is true, accurate, and complete. I am aware that there are significant penalties for submitting false information, including the possibility of fine and imprisonment.

NR 668.04(2) (2) Evaporation of hazardous constituents as the principal means of treatment is not treatment for purposes of an exemption under this section.

NR 668.04 History History: CR 05-032: cr. Register July 2006 No. 607, eff. 8-1-06.