Chapter ATCP 31

ATCP 31.03 History History: Cr. Register, September, 1985, No. 357, eff. 10-1-85; Register, January, 1998, No. 505; correction made under s. 13.93 (2m) (b) 7., Stats.; cr. (1) (d), Register, March, 1998, No. 507, eff. 4-1-98.

ATCP 31.04 ATCP 31.04 Preliminary investigation based on groundwater sample test results.

ATCP 31.04(1) (1) Upon receipt of groundwater test results indicating the presence of a fertilizer substance or pesticide substance in groundwater, the department shall undertake a preliminary investigation to determine whether the presence of the fertilizer substance or pesticide substance may have resulted from, or may be affected by an activity subject to department regulation. The department may investigate on the basis of unofficial groundwater test results if the test results are sufficiently reliable to warrant investigation.

ATCP 31.04(2) (2) If, upon preliminary investigation, the department finds that the presence of a fertilizer substance or pesticide substance in groundwater has resulted from, or may be affected by an activity subject to department regulation, the department shall investigate to determine:

ATCP 31.04(2)(a) (a) Whether the presence of the 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.

ATCP 31.04(2)(b) (b) Whether the concentration of the fertilizer substance or pesticide substance attains or exceeds an enforcement standard or preventive action limit.

ATCP 31.04 Note Note: If an unofficial groundwater test result is not sufficiently reliable to warrant investigation, the department may nevertheless:

ATCP 31.04 Note 1. Refer the groundwater test results to the department of natural resources, with or without a recommendation for official sampling or other action.

ATCP 31.04 Note 2. Refer the groundwater test results to another regulatory agency, with or without a recommendation for action.

ATCP 31.04 Note 3. Refer the groundwater test results to state or local health authorities, and to county agricultural extension agents.

ATCP 31.04 Note 4. Inform affected persons of the groundwater test results, and suggest voluntary measures to prevent, limit or reduce any substance concentrations which may exist in groundwater.

ATCP 31.04 Note 5. Initiate further investigation or research related to the groundwater test results.

ATCP 31.04 History History: Cr. Register, September, 1985, No. 357, eff. 10-1-85.

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

ATCP 31.05(1) (1) Fertilizer and pesticide bulk storage; violation of existing rules. If, upon investigation under s. ATCP 31.04 (2), the department finds that the concentration of a fertilizer substance or pesticide substance in groundwater has resulted from a violation of rules adopted by the department under s. 94.645, Stats., the department may proceed against the violator using any of the following enforcement options, even if the concentration does not exceed an enforcement standard or preventive action limit:

ATCP 31.05(1)(a) (a) A court action to recover a civil forfeiture from the violator, as provided under s. 94.645 (5), Stats.

ATCP 31.05(1)(b) (b) An administrative special order proceeding, as provided under s. 94.645 (4) (a), Stats. Upon violation of a department special order issued under s. 94.645 (4) (a), Stats., the department may seek an injunction under s. 94.645 (4) (b), Stats., or a civil forfeiture under s. 94.645 (5), Stats.

ATCP 31.05(1)(c) (c) A warning notice under s. 93.06 (10), Stats.

ATCP 31.05 Note Note: Rules adopted under s. 94.645, Stats., to regulate fertilizer bulk storage are contained in ch. ATCP 33. Rules adopted under s. 94.645, Stats., to regulate pesticide bulk storage are contained in ch. ATCP 33.

ATCP 31.05(2) (2) Pesticide use; violation of existing statutes or rules. If, upon preliminary investigation under s. ATCP 31.04 (2), the department finds that the concentration of a pesticide substance in groundwater has resulted from a violation of any provision of ss. 94.67 through 94.71, Stats., or any rule adopted under s. 94.69, Stats., the department may proceed against the violator using any of the enforcement options set forth under s. 94.71, Stats., as appropriate, or may issue a warning notice to the violator under s. 93.06 (10), Stats., as appropriate. The concentration of a pesticide substance in groundwater need not attain or exceed an enforcement standard or preventive action limit in order for the department to take enforcement action under this subsection.

ATCP 31.05(3) (3) This section does not limit the department’s responsibility under ss. ATCP 31.06 and 31.07.

ATCP 31.05 History History: Cr. Register, September, 1985, No. 357, eff. 10-1-85.

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

ATCP 31.06(1) (1) Rulemaking. If, upon investigation under s. ATCP 31.04 (2), the department finds that the concentration of a fertilizer substance or pesticide substance in groundwater attains or exceeds an enforcement standard or preventive action limit, and that the concentration has resulted from or may be affected by bulk fertilizer or bulk pesticide storage activities which are not currently regulated by the department, the department shall review its rules adopted under s. 94.645, Stats., to determine whether the rules should be amended pursuant to s. 160.19, Stats. Rule amendments, if any, shall be general in application, and may not be limited in their application to a single bulk fertilizer or bulk pesticide storage facility.

ATCP 31.06 Note Note: Rules adopted under s. 94.645, Stats., to regulate fertilizer bulk storage are contained in ch. ATCP 33. Rules adopted under s. 94.645, Stats., to regulate pesticide bulk storage are contained in ch. ATCP 33.

ATCP 31.06(2) (2) Special orders; statutory limitations on use. The department may not regulate the storage of bulk fertilizer or bulk pesticides by special order under s. 94.645 (4) (a), Stats., except to prohibit or correct a violation of existing rules under s. 94.645, Stats. This does not prevent the department from regulating the storage or other use of bulk pesticides by special order under s. 94.71 (3) (c), Stats., and this chapter, whether or not the storage or use violates existing rules under s. 94.645, Stats.

ATCP 31.06 Note Note: If groundwater contamination is related to fertilizer bulk storage, but the department is unable to respond by rule or special order, the department may refer the matter to the department of natural resources for possible site-specific action under ch. 292, Stats.

ATCP 31.06 History History: Cr. Register, September, 1985, No. 357, eff. 10-1-85.

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

ATCP 31.07(1) (1) Site-specific response; general. If, upon investigation under s. ATCP 31.04 (2), the department finds that the concentration of a pesticide substance in groundwater attains or exceeds an enforcement standard or preventive action limit, and that the concentration has resulted from or may be affected by a pesticide use, the department shall implement an appropriate site-specific response to regulate the pesticide use, pursuant to the applicable provisions of ss. 160.21 (3), 160.23 and 160.25, Stats., and this section. A site-specific response may take any of the forms described under sub. (2). A site-specific response may be implemented to regulate a pesticide use, whether or not the pesticide use violates an existing statute or rule administered by the department. Except as otherwise provided under s. 160.23 or 160.25, Stats., the site-specific response shall be designed to minimize the concentration of the pesticide substance where technically and economically feasible and to restore and maintain compliance with the preventive action limit at the point of standards application, and at other downgradient points to which the pesticide substance may migrate. A site-specific response may be implemented pursuant to substance-specific rules adopted under s. ATCP 31.09.

ATCP 31.07(2) (2) Site-specific response; form of regulatory action.

ATCP 31.07(2)(a) (a) Special orders.

ATCP 31.07(2)(a)1. 1. A site-specific response may include one or more special orders issued under s. 94.71 (3) (c), Stats. The department may issue a special order to a respondent, whether or not the respondent has previously engaged in the use of the pesticide, if the department finds that the special order is necessary to achieve the objectives under sub. (1). The department may, by substance-specific rules under s. ATCP 31.09, prescribe the scope and contents of special orders, and the conditions under which special orders are to be issued. Special orders may be issued on a summary basis, according to criteria set forth under s. 94.71 (3) (c), Stats., and any substance-specific rules adopted under s. ATCP 31.09. Summary special orders are subject to a right of hearing before the department upon request. Special orders required by rule may be signed by a department employee designated in the rule. All other special orders shall be signed by the secretary, or a person individually designated by the secretary.

ATCP 31.07(2)(a)2. 2. A special order may include:

ATCP 31.07(2)(a)2.a. a. A prohibition against the use of a pesticide, subject to s. ATCP 31.08.

ATCP 31.07(2)(a)2.b. b. Limitations on the purposes for which a pesticide may be used, including limitations on the crops or target pests for which a pesticide may be used.

ATCP 31.07(2)(a)2.c. c. Limitations on the rate at which a pesticide is applied.

ATCP 31.07(2)(a)2.d. d. Limitations on the time or frequency of pesticide use.

ATCP 31.07(2)(a)2.e. e. Limitations on the method of pesticide use.

ATCP 31.07(2)(a)2.f. f. Requirements for the training or certification of pesticide applicators or other persons using a pesticide.

ATCP 31.07(2)(b) (b) Rules applicable to a specific locality. A site-specific response may include the adoption of rules whose geographic scope is limited to a specific locality if, in the department’s judgment, the conditions in that locality justify the geographically limited rules. Within the designated locality, rules shall be general in their application, and may not be limited to a single pesticide user. Rules may be adopted on an emergency basis as necessary, pursuant to s. 227.24, Stats. Site-specific rules under this paragraph may supplement, or be incorporated into more general substance-specific rules under s. ATCP 31.09. Site-specific rules may include any of the provisions set forth under s. ATCP 31.09 (2), as applicable.

ATCP 31.07(2)(c) (c) Denial, suspension or revocation of permits. If a permit is required by statute or rule for the use of a pesticide, a site-specific response may include the denial, suspension or revocation of pesticide use permits for the locality covered by the site-specific response. The department may, by substance-specific rules under s. ATCP 31.09, prescribe the terms and conditions under which permits are to be denied, suspended or revoked. If the denial, suspension or revocation of a pesticide use permit is required by rule under certain conditions, the order denying, suspending or revoking the permit may be signed by a department employee designated in the rule. All other orders denying, suspending or revoking permits shall be signed by the secretary, or by a person individually designated by the secretary. Where necessary in an emergency, permits may be summarily suspended, pursuant to s. 227.51, Stats. Circumstances constituting an emergency may be specified by rule. The denial, suspension or revocation of a permit is subject to a right of hearing before the department upon request.

ATCP 31.07 Note Note: In addition to any of the site-specific regulatory responses identified under this paragraph, the department may take other actions in response to a finding of pesticide contamination which attains or exceeds an enforcement standard or preventive action limit. The department may, for example:

ATCP 31.07 Note 1. Review its rules governing pesticide use, pursuant to s. 160.19, Stats., and s. ATCP 31.09

ATCP 31.07 Note 2. Disseminate information concerning the groundwater contamination, and notify affected persons.

ATCP 31.07 Note 3. Notify state or local health authorities and county agricultural extension agents of the groundwater contamination.

ATCP 31.07 Note 4. Initiate or recommend further investigation or research concerning the groundwater contamination.

ATCP 31.07(3) (3) Site-specific response; maximum geographic scope. A site-specific response required under this section does not include a regulatory action which extends beyond the groundwater recharge zone of the aquifer from which the groundwater sample was collected at the point of standards application. If the pesticide substance has migrated, or may migrate through more than one aquifer, a site-specific response may extend, at a maximum, to the boundary of the outermost recharge zone providing recharge to an affected aquifer. If the natural boundary of a groundwater recharge zone is not readily definable, a site-specific response may extend, at a maximum, to the whole of every land parcel which, in the judgment of the department, may be wholly or partially located within the relevant groundwater recharge zone. All or a portion of any land parcel may be exempted from a site-specific response upon proof that the parcel or portion is located outside the groundwater recharge zone to which the site-specific response is applicable. Within the maximum geographic limits specified under this section, the department may determine the geographic scope of the site-specific response, based on the objective of restoring and maintaining compliance with the preventive action limit and minimizing the concentration of the pesticide substance in groundwater where technically and economically feasible, at the point of standards application and other downgradient points to which the pesticide substance may migrate. For purposes of administrative efficiency, the geographic scope of a site-specific response may be delineated according to a regular geometric pattern.

ATCP 31.07(4) (4) Site-specific responses; factors to be considered.

ATCP 31.07(4)(a) (a) In the department’s choice of a site-specific response, or in its adoption of substance-specific rules under s. ATCP 31.09 prescribing nondiscretionary site-specific responses, the department shall consider the general risks and benefits of the possible actions to the extent authorized by relevant law, and shall consider the following specific factors to the extent feasible:

ATCP 31.07(4)(a)1. 1. The concentration of the pesticide substance in groundwater at the point of standards application, and any known changes in concentration.

ATCP 31.07(4)(a)2. 2. The concentration of the pesticide substance at other points of standards application, if known, and any known changes in concentration.

ATCP 31.07(4)(a)3. 3. The extent, age and reliability of groundwater sample data indicating the presence of the pesticide substance in groundwater.

ATCP 31.07(4)(a)4. 4. The specific activities or practices from which the pesticide contamination originated, if known, and the locations at which the source activities or practices are conducted.

ATCP 31.07(4)(a)5. 5. The previously demonstrated propensity, if any, for the pesticide substance to leach to groundwater as a result of normal use.

ATCP 31.07(4)(a)6. 6. Environmental conditions which may reasonably affect the risk of groundwater contamination, including soil conditions, depth to groundwater, and subsurface geological conditions. Differences in local environmental conditions may not be used to justify a difference in site-specific responses between localities unless the differences in environmental conditions are reasonably known to affect the relative risk of groundwater contamination between localities.

ATCP 31.07(4)(a)7. 7. Differences in local pesticide use practices which are reasonably known to affect the risk of groundwater contamination.

ATCP 31.07(4)(a)8. 8. The environmental fate of the pesticide substance in soil and groundwater, to the extent known.

ATCP 31.07(4)(a)9. 9. The direction and rate of groundwater movement within the affected groundwater recharge zone, if known.

ATCP 31.07(4)(a)10. 10. The potential uses of the affected groundwater.

ATCP 31.07(4)(a)11. 11. The extent and likelihood of human exposure to the pesticide substance in groundwater.

ATCP 31.07(4)(a)12. 12. The alternative measures which are available to prevent or control groundwater contamination, the relative cost and effectiveness of each alternative, and the risks associated with each alternative including the risk of adverse environmental effects.

ATCP 31.07(4)(b) (b) Except as otherwise required by law, the department is not required to make a written record of its consideration under this subsection. This subsection may not be construed to limit the department’s responsibility under s. 160.19 or 160.25, Stats.

ATCP 31.07(5) (5) Site-specific response; prohibitions against pesticide use. If a site-specific response under this section prohibits a pesticide use in the locality covered by the site-specific response, the prohibition shall comply with the applicable provisions of s. ATCP 31.08.

ATCP 31.07 History History: Cr. Register, September, 1985, No. 357, eff. 10-1-85; correction in (2) (c) and (d) made under s. 13.93 (2m) (b) 7., Stats., Register, March, 1993, No. 447.

ATCP 31.08 ATCP 31.08 Prohibitions against pesticide use.

ATCP 31.08(1) (1) Site-specific prohibition in response to groundwater contamination which exceeds an enforcement standard. If, at a point of standards application, the concentration of a pesticide substance in groundwater attains or exceeds an enforcement standard, and if the concentration has resulted from or may be affected by a pesticide use, the department shall, as a site-specific response under s. ATCP 31.07, prohibit the pesticide use on a site-specific basis unless the department is shown, and determines to a reasonable certainty by the greater weight of the credible evidence, that an alternative response will achieve compliance with the enforcement standard. The scope and duration of the site-specific prohibition shall be reasonably designed to achieve and maintain compliance with the enforcement standard at the point of standards application, and at other downgradient points to which the pesticide substance may migrate. A prohibition may remain in effect indefinitely unless the department is shown, and determines, that resumption of the pesticide use is not likely to cause a renewed or continued violation of the enforcement standard. The department’s responsibility to initiate a site-specific prohibition under s. 160.25, Stats., and this subsection is not affected by sub. (2), or by contemporaneous findings that concentrations of the same pesticide substance at other points of standards application fall below the enforcement standard.

ATCP 31.08(2) (2) Site-specific prohibition in response to groundwater contamination which exceeds a preventive action limit, but not an enforcement standard. If, at a point of standards application, the concentration of a pesticide substance in groundwater attains or exceeds a preventive action limit but not an enforcement standard, the department may not implement a site-specific response under s. ATCP 31.07 prohibiting a pesticide use unless the department:

ATCP 31.08(2)(a) (a) Determines, pursuant to s. 160.23 (4), Stats., that no less restrictive response would prevent the violation of an enforcement standard at the point of standards application.

ATCP 31.08(2)(b) (b) Establishes the basis for the geographic scope and duration of the prohibition; and

ATCP 31.08(2)(c) (c) Limits the scope and duration of the prohibition to that which is reasonably necessary to maintain compliance with the enforcement standard at the point of standards application.

ATCP 31.08(3) (3) Statewide or regional prohibition. The department may, by rule under s. ATCP 31.09, prohibit a pesticide use on a statewide or regional basis, as well as on a site-specific response basis, if the department does all of the following:

ATCP 31.08(3)(a) (a) Determines that groundwater contamination has occurred or is likely to occur on a statewide or regional basis as a result of the pesticide use.

ATCP 31.08(3)(b) (b) Determines that a statewide or regional prohibition is necessary to achieve or maintain compliance with an enforcement standard. In determining the need for a statewide or regional prohibition, the department shall consider:

ATCP 31.08(3)(b)1. 1. The extent, age, reliability, and geographical distribution of groundwater sample test data; and

ATCP 31.08(3)(b)2. 2. The extent to which local conditions and circumstances can reliably be considered characteristic of a larger region, or of the state as a whole.

ATCP 31.08(3)(c) (c) Determines that compliance with the enforcement standard cannot reasonably be achieved and maintained by other, less restrictive measures.

ATCP 31.08(3)(d) (d) Establishes the basis for the scope and duration of the prohibition.

ATCP 31.08(3)(e) (e) Limits the scope and duration of the prohibition to that which is reasonably necessary to achieve and maintain compliance with the enforcement standard.

ATCP 31.08(4) (4) Repealing a site-specific prohibition.

ATCP 31.08(4)(a) (a) The department may repeal or modify a site-specific prohibition under sub. (1) if all of the following conditions are met:

ATCP 31.08(4)(a)1. 1. Tests on at least 3 consecutive groundwater samples, drawn from each point of standards application in the prohibition area at which the concentration of the pesticide substance previously attained or exceeded the enforcement standard, show that the concentration of that pesticide substance at that point of standards application has fallen to and remains at a level which is at or below the level specified by the department under par. (c). The 3 consecutive samples shall be collected from each point of standards application at intervals of at least 6 months, with the first sample being collected at least 6 months after the effective date of the site-specific prohibition. A monitoring well approved by the department may be substituted for any point of standards application which is no longer available for testing, provided that the monitoring well qualifies as a point of standards application under s. ATCP 31.03.

ATCP 31.08(4)(a)2. 2. Tests of groundwater samples drawn from other points of standards application in the prohibition area during the retesting period under subd. 1., if any, reveal no other concentrations of the pesticide substance that exceed the level specified by the department under par. (c).

ATCP 31.08(4)(a)3. 3. The department determines, based on credible scientific evidence, that renewed use of the pesticide in that prohibition area is not likely to cause a renewed violation of the enforcement standard.

ATCP 31.08 Note Note: If a site-specific prohibition is created by rule, it can only be repealed or modified by rule. If a site-specific prohibition is created by special order under s. 94.71 (3) (c), Stats., it can only be repealed or modified by special order. This subsection establishes conditions which must be met before the department adopts a rule or issues a special order repealing or modifying a site-specific prohibition. The subsection does not, by itself, repeal or modify any site-specific prohibition.

ATCP 31.08 Note The department plans to continue its program of groundwater research, and will continue to monitor groundwater in areas where there is significant potential for repealing or modifying a prohibition. However, the department is not legally obligated to conduct specific groundwater research or perform specific groundwater tests at the request of a person who wishes to have a site-specific prohibition repealed or modified.

ATCP 31.08 Note The department may accept test results from other sources if the department considers those test results reliable. Persons who question the reliability of test results used to maintain, modify or repeal a prohibition may submit information showing why the test results are unreliable. If the department finds that there are reasonable grounds to question the reliability of any test result, the department will attempt to perform additional sampling and testing to verify the test result.

ATCP 31.08(4)(b) (b) As a condition to repealing or modifying a site-specific prohibition under par. (a), the department may do any of the following:

ATCP 31.08(4)(b)1. 1. Provide for continued groundwater monitoring at points of standards application where the concentration of the pesticide substance previously attained or exceeded the enforcement standard, or at monitoring wells substituted for those points of standards application under par. (a) 1. At a minimum, groundwater from those points of standards application or monitoring wells shall be sampled and tested during the second and fifth years after the department repeals a site-specific prohibition.