Chapter ATCP 31

ATCP 31.04   Preliminary investigation based on groundwater sample test results.

ATCP 31.05   Violation of existing statute or rule; enforcement options.

ATCP 31.06   Fertilizer or pesticide bulk storage; groundwater contamination exceeding enforcement standard or preventive action limit; regulatory options.

ATCP 31.07   Pesticide use; groundwater contamination exceeding enforcement standard or preventive action limit; site-specific response.

ATCP 31.08   Prohibitions against pesticide use.

ATCP 31.09   Rulemaking to control pesticide contamination of groundwater; general.

Ch. ATCP 31 Note Note: Chapter Ag 161 was renumbered ch. ATCP 31 under s. 13.93 (2m) (b) 1., Stats., Register, April, 1993, No. 448.

Ch. ATCP 31 Note Prefatory Note: (1) The department of agriculture, trade and consumer protection has authority to regulate fertilizer and pesticide bulk storage under s. 94.645, Stats., and pesticide use under ss. 94.67 through 94.71, Stats. Activities subject to department regulation may, under some circumstances, result in the presence of fertilizer substances or pesticide substances in groundwater. Under ch. 160, Stats., the department of natural resources is required to establish numerical standards, consisting of enforcement standards and preventive action limits, for certain substances in groundwater. If a fertilizer substance or pesticide substance is found in groundwater, the department will consider whether the presence of the fertilizer substance or pesticide substance has resulted from, or may be aggravated by an activity subject to department regulation. If the presence of the fertilizer or pesticide substance has resulted from a violation of an existing statute, rule or order administered by the department, the department may seek appropriate enforcement action against the violator, whether or not the contamination exceeds an enforcement standard or preventive action limit adopted by the department of natural resources. If, at a point of standards application, the concentration of a fertilizer substance or pesticide substance in groundwater attains or exceeds an enforcement standard or preventive action limit, the department may take site-specific regulatory action to prevent further groundwater degradation or restore groundwater quality, whether or not the substance concentration has resulted from a violation of an existing statute, rule or order. Site-specific regulatory action will be consistent with ch. 160, Stats., and this chapter. The department will also adopt substance-specific rules, as appropriate under ss. 94.69, 160.19 and 160.21, Stats., for each pesticide substance for which an enforcement standard and preventive action limit are established by the department of natural resources. Rules may include preventive measures designed to minimize the presence of pesticide substances in groundwater statewide. Rules may also include requirements for the implementation of site-specific regulatory responses under specified conditions.

Ch. ATCP 31 Note (2) This chapter establishes certain elements of the department’s program for the prevention and control of groundwater contamination where it appears that groundwater contamination has resulted from or may be aggravated by activities subject to department regulation. This chapter includes:

Ch. ATCP 31 Note (a) Standards for the collection, handling and analysis of official groundwater samples, to ensure the reliability of sample test results used by the department as a basis for regulatory or enforcement action.

Ch. ATCP 31 Note (b) The points of standards application at which concentrations of a fertilizer substance or pesticide substance in groundwater may be measured to determine whether an enforcement standard or preventive action limit has been attained or exceeded. These points of standards application are defined, pursuant to s. 160.21 (2), Stats., for activities subject to department regulation.

Ch. ATCP 31 Note (c) The preliminary investigative steps to be taken by the department upon receipt of groundwater sample test results which indicate the presence of a fertilizer substance or pesticide substance in Wisconsin groundwater.

Ch. ATCP 31 Note (d) The enforcement options which are available to the department if the department finds, upon investigation, that the presence of a fertilizer substance or pesticide substance in groundwater has resulted from a violation of an existing statute, rule or order administered by the department under s. 94.645, Stats., or ss. 94.67 through 94.71, Stats.

Ch. ATCP 31 Note (e) The site-specific regulatory options which are available to the department under s. 94.645, Stats., or ss. 94.67 through 94.71, Stats., if, at a point of standards application, the concentration of a fertilizer substance or pesticide substance is found to attain or exceed an enforcement standard or preventive action limit.

Ch. ATCP 31 Note (f) The general criteria to be considered by the department in its choice of a site-specific regulatory response, or in the adoption of rules which require non-discretionary site-specific responses under specific conditions.

Ch. ATCP 31 Note (g) Requirements and limitations governing the prohibition of pesticide uses, whether by site-specific regulatory responses or by rule.

Ch. ATCP 31 Note (h) A commitment to adopt substance-specific rules, as appropriate under ss. 94.69, 160.19 and 160.21, Stats., for each pesticide substance for which an enforcement standard and preventive action limit are adopted by the department of natural resources. Rules may include preventive measures designed to minimize the presence of pesticide substances in groundwater statewide. Rules may also include requirements for the implementation of site-specific regulatory responses under specified conditions.

Ch. ATCP 31 Note (3) This chapter does not limit the department’s rulemaking authority under ss. 94.645, 94.69, 160.19, or 160.21, Stats. In the exercise of its rulemaking authority, the department may consider any information which may be relevant to the rulemaking proceeding, whether or not the information is derived from Wisconsin groundwater samples. The finding of a fertilizer or pesticide substance in groundwater, at a level which equals or exceeds an enforcement standard or preventive action limit, is not a prerequisite to the exercise of the department’s rulemaking authority under ss. 94.645, 94.69, 160.19, or 160.21, Stats.

Ch. ATCP 31 Note (4) This chapter does not limit the department in the exercise of any of its statutory authority, where the department determines that the exercise of its authority is necessary to comply with a statutory mandate, or to safeguard the public health, safety or welfare.

Ch. ATCP 31 Note (5) General rules governing pesticide use and control are contained in ch. ATCP 29. Rules adopted under s. 94.645, Stats., to regulate fertilizer and pesticide bulk storage are contained in ch. ATCP 33.

ATCP 31.01 ATCP 31.01 Definitions. As used in this chapter:

ATCP 31.01(1) (1) “Activity subject to department regulation” means:

ATCP 31.01(1)(a) (a) The bulk storage of fertilizer or pesticides, to the extent that the bulk storage is subject to possible regulation by the department under s. 94.645, Stats.

ATCP 31.01(1)(b) (b) Pesticide use, to the extent that the pesticide use is subject to possible regulation by the department under ss. 94.67 through 94.71, Stats.

ATCP 31.01(2) (2) “Department” means the state of Wisconsin department of agriculture, trade and consumer protection.

ATCP 31.01(3) (3) “Enforcement standard” means a numerical value expressing the concentration of a substance in groundwater which is adopted under ss. 160.07 and 160.09, Stats.

ATCP 31.01(4) (4) “Fertilizer” means a fertilizer as defined in s. 94.64 (1) (e), Stats., except that it does not include anhydrous ammonia.

ATCP 31.01(5) (5) “Fertilizer substance” means either of the following for which an enforcement standard or preventive action limit has been adopted by the department of natural resources:

ATCP 31.01(5)(a) (a) A fertilizer; or

ATCP 31.01(5)(b) (b) A degradation product or metabolic product of fertilizer.

ATCP 31.01(6) (6) “Groundwater” means any of the waters of the state, as defined in s. 280.01 (2), Stats., occurring in a saturated sub-surface geological formation of rock or soil.

ATCP 31.01(7) (7) “Official groundwater sample” means a groundwater sample from which an official groundwater test result is obtained.

ATCP 31.01(8) (8) “Official groundwater test result” means a groundwater test result which is:

ATCP 31.01(8)(a) (a) Obtained by department analysis of a groundwater sample collected by the department or its agent; or

ATCP 31.01(8)(b) (b) Reported and certified to the department by the department of natural resources pursuant to s. ATCP 31.02.

ATCP 31.01(9) (9) “Nonpotable water supply” means an excavation or opening into the ground made by digging, boring, drilling, driving or other methods for the purpose of obtaining groundwater for a use other than human consumption or preparation of food products.

ATCP 31.01(10) (10) “Pesticide” means a pesticide as defined in s. 94.67 (25), Stats., or a pesticide active ingredient as defined in s. 94.67 (1), Stats.

ATCP 31.01(11) (11) “Pesticide substance” means any of the following for which an enforcement standard or preventive action limit has been adopted by the department of natural resources:

ATCP 31.01(11)(a) (a) A pesticide;

ATCP 31.01(11)(b) (b) An isomer of a pesticide; or

ATCP 31.01(11)(c) (c) A degradation product or metabolic product of a pesticide.

ATCP 31.01(12) (12) “Pesticide use” means the mixing, use, application, handling, transport, storage or disposal of a pesticide.

ATCP 31.01(13) (13) “Point of standards application” means a location at which the concentration of a substance in groundwater may be measured to determine whether a preventive action limit or enforcement standard has been attained or exceeded, as provided in s. 160.21 (2) (b), Stats., and s. ATCP 31.03.

ATCP 31.01(14) (14) “Preventive action limit” means a numerical value expressing the concentration of a substance in groundwater which is adopted under s. 160.15, Stats.

ATCP 31.01(15) (15) “Property boundary” means the boundary of a total contiguous parcel of land owned by a common owner, regardless of whether public or private roads run through the parcel.

ATCP 31.01(16) (16) “Secretary” means the secretary of the department.

ATCP 31.01(17) (17) “Site-specific response” means a localized regulatory response by the department to groundwater sample findings obtained at a point of standards application, as provided in s. ATCP 31.07.

ATCP 31.01(18) (18) “Special order” means an order of the department which is directed to an individually named or identified respondent.

ATCP 31.01(19) (19) “Substance” means any solid, liquid, semisolid, dissolved solid or gaseous material, naturally occurring or synthetic chemical, parameter for measurement of water quality or biological organism which, in its original form, or as a metabolic or a degradation or waste product, may decrease the quality of groundwater.

ATCP 31.01 History History: Cr. Register, September, 1985, No. 357, eff. 10-1-85; correction made under s. 13.93 (2m) (b) 5., Stats., Register, February, 1993, No. 447; corrections in (6) made under s. 13.93 (2m) (b) 7., Stats., Register, January, 1998, No. 505.

ATCP 31.02 ATCP 31.02 Groundwater test results; use by department.

ATCP 31.02(1) (1) Use of official groundwater test results. An official groundwater test result is presumed to be reliable for purposes of regulatory or enforcement action under this chapter whether or not the department collected or analyzed the official groundwater sample.

ATCP 31.02(2) (2) Use of unofficial groundwater test results. A regulatory or enforcement action under this chapter may be based on a groundwater test result which is not an official groundwater test result only if the department determines that the unofficial groundwater test result is reliable for purposes of the regulatory or enforcement action.

ATCP 31.02 Note Note: If an unofficial groundwater sample is not determined to be reliable for purposes of regulatory or enforcement action under this chapter, the department may nevertheless:

ATCP 31.02 Note 1. Refer the unofficial groundwater test result to the department of natural resources, with or without a recommendation for official sampling and testing.

ATCP 31.02 Note 2. Inform affected persons of the unofficial groundwater test result.

ATCP 31.02 Note 3. Refer the unofficial groundwater test result to state or local health authorities, and to county agricultural extension agents.

ATCP 31.02 Note 4. Initiate further investigation or research related to the unofficial groundwater sample result.

ATCP 31.02(3) (3) Memorandum of understanding. Pursuant to ss. 160.21 (2) (e) and 160.27, Stats., the department shall enter into a memorandum of understanding with the department of natural resources to ensure the reliability of official groundwater test results used by the department for purposes of regulation and enforcement under this chapter. The memorandum of understanding shall govern the reporting and certification of official groundwater test results to the department by the department of natural resources. It shall also govern the collection, handling and analysis of official groundwater samples by the department of natural resources or its designated agents. The memorandum of understanding shall include:

ATCP 31.02(3)(a) (a) Standards for the collection of official groundwater samples, including standards related to:

ATCP 31.02(3)(a)1. 1. Collection equipment and containers.

ATCP 31.02(3)(a)2. 2. Collection procedures.

ATCP 31.02(3)(a)3. 3. Collection records.

ATCP 31.02(3)(b) (b) Standards for the handling of official groundwater samples, including:

ATCP 31.02(3)(b)1. 1. Temperature conditions under which samples are to be kept.

ATCP 31.02(3)(b)2. 2. Time periods within which samples are to be analyzed.

ATCP 31.02(3)(b)3. 3. Chain of custody requirements.

ATCP 31.02(3)(c) (c) Standards for the analysis of official groundwater samples, including:

ATCP 31.02(3)(c)1. 1. Required quality assurance programs for laboratories engaged in the analysis of official groundwater samples under this chapter.

ATCP 31.02(3)(c)2. 2. Control sample requirements.

ATCP 31.02(3)(c)3. 3. Required analytical methods.

ATCP 31.02(3)(c)4. 4. Required confirmation of analytical results.

ATCP 31.02(3)(c)5. 5. Instrument calibration and maintenance requirements.

ATCP 31.02(3)(c)6. 6. Required analytical worksheets and documentation.

ATCP 31.02(3)(c)7. 7. Chain of custody requirements in the laboratory.

ATCP 31.02(3)(c)8. 8. Requirements for the timely reporting of analytical results.

ATCP 31.02(3)(c)9. 9. Continuing sample custody requirements.

ATCP 31.02(3)(c)10. 10. Access to laboratory records by the department and the department of natural resources.

ATCP 31.02(3)(d) (d) Contract requirements applicable to designated agents engaged in the collection or analysis of official groundwater samples under this chapter.

ATCP 31.02(3)(e) (e) Reports and certifications required to accompany official groundwater samples and test results obtained by designated agents of the department of natural resources.

ATCP 31.02(3)(f) (f) Standards for the reporting and certification of official groundwater test results to the department by the department of natural resources.

ATCP 31.02(4) (4) Department contracts with agents designated to collect or analyze official groundwater samples. Every person or entity designated to collect or analyze an official groundwater sample as the agent of the department, rather than as the agent of the department of natural resources, shall first enter into a written contract with the department. Contracts shall include specific standards for the collection, handling and analysis of official groundwater samples, to ensure the reliability of official groundwater test results used by the department for purposes of regulation and enforcement under this chapter. Agents contracting directly with the department shall be held to the same requirements which are applicable to agents designated by the department of natural resources pursuant to a memorandum of understanding under sub. (3).

ATCP 31.02 History History: Cr. Register, September, 1985, No. 357, eff. 10-1-85.

ATCP 31.03 ATCP 31.03 Points of standards application.

ATCP 31.03(1) (1) To determine whether an enforcement standard or preventive action limit for a fertilizer substance or pesticide substance has been attained or exceeded, the concentration of the fertilizer substance or pesticide substance shall be measured at a point of standards application. Except as otherwise provided in this section, points of standards application for fertilizer substances and pesticide substances include:

ATCP 31.03(1)(a) (a) A community water system covered under ch. NR 811.

ATCP 31.03(1)(b) (b) A private water supply, high capacity water system, school water system or public water system covered under ch. NR 812.

ATCP 31.03(1)(c) (c) A monitoring well or other groundwater sample source, regardless of whether the well or source is covered under par. (a) or (b), if the well or source is reasonably designed and of adequate depth to permit the collection of representative groundwater samples.