3. Explanation of Agency Authority:
The statutory authority for developing PFOS and PFOA surface water quality standards for human health protection, for developing factors for listing waters as impaired for PFOS or PFOA, and for promulgating Wisconsin Pollutant Discharge Elimination System (WPDES) permitting procedures to implement the new standards is as follows:
— Section 281.12, Wis. Stats., grants the department general supervision and control to carry out the planning, management, and regulatory programs necessary for prevention and reduction of water pollution and for improvement of water quality. — Section 281.13(1)(a) and (b), Wis. Stats., give the department the authority to create rules to research and assess water quality in the state. — Section 281.15, Wis. Stats., mandates that the department promulgate water quality standards, including water quality criteria and designated uses. It recognizes that different use categories and criteria are appropriate for different types of waterbodies, and that the department shall establish criteria which are not more stringent than reasonably necessary to ensure attainment of the designated use for the waterbodies. — Section 281.65(4)(c) and (cd), Wis. Stats., directs the department to prepare a list of impaired waters. — Section 283.13(5), Wis. Stats., states that the department shall establish more stringent limitations than required under subs. (3) and (4) when necessary to comply with water quality standards. — Section 283.31(3) and (4), Wis. Stats., state that the department may issue a permit upon condition that the permit contains limitations necessary to comply with any applicable federal law or regulation, state water quality standards, and total maximum daily loads. — Section 283.37, Wis. Stats., gives the department authority to promulgate rules regarding permit applications. Section 283.55, Wis. Stats., gives the department authority to impose monitoring and reporting requirements. — Section 283.83, Wis. Stats., requires that the department establish a continuing planning process and that plans shall include implementation procedures including compliance schedule for new water quality standards. — Section 227.11(2), Wis. Stats., provides the department with the authority to promulgate rules that are necessary to administer the specific statutory directives in chs. 281 and 283, Wis. Stats. 4. Related Statutes or Rules:
The proposed rules are related to three other sets of rules currently in progress:
— Rule package DG-15-19 is proposing to establish groundwater standards for several compounds including PFOS and PFOA for the protection of human health.
— Rule package DG-24-19 is proposing drinking water maximum contaminant levels (MCLs) for PFOS & PFOA.
— Rule package WA-07-20 is proposing to regulate class B firefighting foams containing PFAS.
— Rule package WY-23-13 is proposing revisions to ch. NR 102, Wis. Adm. Code, in order to add text regarding waterbody assessments and biological thresholds, which are topics unrelated to this rule but may affect numbering for this rule package. — Section 299.48, Wis. Stats., regulates class B firefighting foams containing PFAS. — Section 292.11, Wis. Stats., regulates discharges of hazardous substances. With regard to existing regulations, these proposed rules relate to surface water quality standards and the Wisconsin Pollutant Discharge Elimination System (WPDES) wastewater permit program. Related rules include chs. NR 102, 104, 105, and 106, Wis. Adm. Code, which contain Wisconsin’s surface water quality standards and their application, and chs. NR 200 to 299, Wis. Adm. Code., which contain requirements for the WPDES permit program. Chapter 283, Wis. Stats., contains the statutory authority and requirements for the WPDES permit program. 5. Plain Language Analysis:
Poly- and perfluoroalkyl substances (PFAS) are human-made, organic compounds that have been manufactured for use in non-stick coatings, waterproof fabrics, firefighting foams, food packaging, and many other applications since the 1940s. PFAS are highly resistant to degradation and have been detected globally in water, sediment, and wildlife. This global distribution is of concern as PFAS have documented toxicity to animals and because epidemiological studies have suggested probable links to several human health effects. In Wisconsin, PFAS have been detected in drinking and surface water near sources of industrial use or manufacture and near spill locations. Perfluorooctane sulfonate (PFOS) has been found in fish tissue resulting in the issuance of special fish consumption advisories for some surface waters in the state.
The proposed rules include a water quality standard for two types of PFAS: PFOS and perfluorooctanoic acid (PFOA). Under the Clean Water Act, surface water quality standards can include criteria that are numeric or narrative and designated uses (e.g. aquatic life use, recreational use, and public health and welfare). Wisconsin’s existing Administrative Codes contain both numeric and narrative criteria for toxic substances:
—Chapter NR 105, Wis. Adm. Code, contains specific numeric criteria for numerous toxic pollutants as well as formulas for calculating numeric criteria and secondary values for toxics that do not yet have promulgated criteria. —Section NR 102.04(1)(d), Wis. Adm. Code, contains Wisconsin’s narrative criteria for toxics. This existing rule states that substances in concentrations or combinations which are toxic or harmful to humans shall not be present in amounts found to be of public health significance [emphasis added], nor shall substances be present in amounts which are acutely harmful to animal, plant or aquatic life. The proposed PFOS and PFOA standard protects public health and recreational uses of surface waters by establishing criteria that contain both narrative provisions and numeric criteria. The narrative and numeric criteria interpret Wisconsin’s existing narrative standards under ss. NR 105.04(4m) and 102.04, Wis. Adm. Code, with regard to two toxic substances, PFOS and PFOA. The proposed rule defines levels of public health significance for the two types of PFAS based on preventing adverse effects from contact with or ingestion of surface waters of the state, or from ingestion of fish taken from waters of the state. —For PFOS, the proposed level of public health significance is 8 ng/L for all waters except those that cannot naturally support fish and do not have downstream waters that support fish.
—For PFOA, the proposed levels of public health significance are 20 ng/L in waters classified as public water supplies under ch. NR 104, Wis. Adm. Code, and 95 ng/L for other surface waters. Related to the proposed PFOS and PFOA standards, the proposed rule also includes assessment protocols that clarify when a surface water that contains levels of PFOS or PFOA above the criteria in the narrative standard should be listed on the state’s impaired waters list.
Additionally, this rule includes revisions to ch. NR 106, Wis. Adm. Code, that address WPDES permit implementation procedures for the new PFOS and PFOA standard. With regard to permit implementation of the PFOS and PFOA criteria, DNR is proposing source reduction as a first step toward reducing levels of PFOS and PFOA in the effluent rather than requiring treatment up front because source reduction is the most cost effective approach to reducing or eliminating PFOS and PFOA in wastewater discharges. Source reduction also avoids the generation of contaminated carbon filters from treatment systems which will contain higher levels of PFOA and PFOS that will have to be disposed of in a safe manner. The proposed rule establishes WPDES permit requirements for PFOS and PFOA discharges to surface waters of the state, in ch. NR 106 – Subchapter VIII, Wis Adm. Code, including: the determination of the need for a PFOS and PFOA Minimization Plan based on data generation in a reissued permit, a general schedule for PFOS and PFOA Minimization Plan permit implementation procedures, and PFOS and PFOA Minimization Plan requirements. The proposed permit requirements include standard PFOS and PFOA sampling frequencies for categories of permitted dischargers. If the department does not believe that PFOS or PFOA is present in a permittee’s discharged effluent, sampling may be waived. Based on the effluent data collected, the proposed rule establishes procedures for determining whether a permitted facility’s discharge contains PFOS or PFOA at levels that have the reasonable potential to cause or contribute to an exceedance of the PFOS or PFOA standard. For permitted facilities that have the reasonable potential to exceed the PFOS or PFOA standard, the proposed rule requires that the permittee develop and implement a PFOS and PFOA Minimization Plan in accordance with the timelines in the rule and WPDES permit schedule. The permittee must also continue sampling for PFOS and PFOA. The department expects that for nearly all WPDES permitted facilities with discharges to surface waters as well as industrial facilities that discharge wastewater to publicly owned treatment plants, source reduction actions outlined in minimization plans will reduce PFOS and PFOA discharges to levels that are below the public health based standard. The rule allows for up to 85 months of PFOS and PFOA minimization plan implementation. At subsequent permit reissuances after the department’s initial determination that a permitted discharge may exceed the PFOS or PFOA standard, for a maximum period of up to 85 months, the department will evaluate progress in source reduction activities and proposed activities for the next permit term and also evaluate the effluent quality of the permitted facility. The proposed rule provides:
—If levels of PFOS or PFOA in the effluent have been eliminated or reduced to a concentration where there is no longer reasonable potential to exceed the standard, then the department may remove future scheduled actions, the permittee will be required to maintain effluent quality at levels that would not have the reasonable potential to cause or contribute to the exceedance of PFOS or PFOA standards, and continued monitoring may be required in the permit.
—If there is still reasonable potential to exceed the standard the department may request updates be made to the PFOA and PFOS minimization plan and may include revised related terms and conditions, including revisions to the schedule in the reissued permit.
Because past pollutant minimization plans for other pollutants such as mercury have been shown to result in a 43 percent (median) reduction in effluent concentrations and based on relatively low initial concentrations of PFOS and PFOA observed in permittees’ effluents, the department predicts that only a couple of industrial facilities (indirect dischargers) in the state will eventually have to install treatment to comply with the PFOS and PFOA standard. In these cases, the proposed rule allows a compliance schedule for installation of treatment technology.
In the event treatment becomes necessary for a WPDES permit holder, pursuant to s. 283.15, Wis. Stats., the permitted facility may apply for an economic variance if installation of treatment technology will cause substantial and widespread adverse social and economic impacts in the area where the permittee is located. Finally, this rule adds specifications for the preservation and holding times of aqueous, biosolids (sludge), and tissue samples that will be analyzed for PFAS in ch. NR 219, Wis. Adm. Code. 6. Summary of, and Comparison with, Existing or Proposed Federal Statutes and Regulations:
Federal statutes and regulations direct states to establish and periodically review water quality standards. State adoption of water quality standards and revisions to standards require EPA approval pursuant to 40 CFR 131.20 and 131.21. — 33 USC s. 1313(c) (section 303(c) of the Clean Water Act) requires that states periodically review and modify or adopt, if necessary, water quality standards. This requirement applies to all surface waters in the state.
— 33 USC s. 1314(a) (section 304 of the Clean Water Act) requires that EPA develop and publish criteria for water quality for all waters for uses such as aquatic life, public health protection, and recreation.
— 40 CFR s. 130.3 defines water quality standards as setting water quality goals for a waterbody that will protect its designated uses (such as protection of fish, wildlife, recreation, and public health and welfare). Criteria will be set to protect those uses. — 40 CFR s. 131.4 specifies that states are responsible for reviewing, establishing and revising their own water quality standards. — 40 CFR ss. 131.10 and 11 require states to develop water quality standards including uses and criteria to protect the uses. 40 CFR s. 131.11 (b) states that the criteria must be based on federal guidance, federal guidance modified to reflect site-specific criteria, or other scientifically defensible methods. — 40 CFR s. 131.11 specifies that criteria must protect the designated uses and that criteria must be based on sound scientific rationale and must contain sufficient parameters or constituents to protect the designated use. Furthermore, states must review water quality data and information on discharges to identify specific water bodies where toxic pollutants may be adversely affecting water quality or the attainment of the designated use or where the levels of toxic pollutants are at a level to warrant concern, and must adopt criteria for such toxic pollutants applicable to the water body sufficient to protect the designated use. — 40 CFR 131.20 requires states to periodically review water quality standards. — 40 CFR 132 and Appendices contain requirements for developing water quality standards in the Great Lakes System as well as implementation procedures for the standards and National Pollutant Discharge Elimination System (NPDES) permitting requirements for point source discharges to the Great Lakes System. — 40 CFR 123.25 lists the federal regulations in 40 CFR 122 and 124 that states must follow in the administration of the NPDES permit program. State rules must be at least as stringent as these federal requirements. EPA has neither promulgated specific water quality standards for PFOS or PFOA nor proposed criteria under section 304(a) of the Clean Water Act. EPA typically relies on states to take the initiative and develop water quality standards because states have varying types of fish and aquatic life species and varying types of waterbodies within, and adjacent to, their borders. Occasionally, EPA will specifically direct states to promulgate water quality standards or promulgate procedures for deriving criteria for pollutants in advance of state efforts, and then require that states adopt water quality standards for the pollutant that are at least as stringent as EPA’s procedure or standard. EPA has not expressly directed states to develop water quality standards for PFAS at this time, although states do not need EPA approval to begin developing water quality standards and have the discretion to develop water quality criteria for any pollutant. EPA has stated that it has plans to promulgate both aquatic life criteria and human health criteria for PFAS, but any such recommended criteria won’t be established for several years.
The method of calculating numeric criteria in ch. NR 105, Wis. Adm. Code, reflects procedures established by EPA for Great Lakes states. As part of this rulemaking effort, the department also conducted preliminary calculations of numeric criteria using the procedures outlined ch. NR 105, Wis. Adm. Code. At this time, however, the department selected a different methodology to develop public health based PFOS and PFOA criteria. Pursuant to s. NR 105.02 (2), Wis. Adm. Code, the department has authority to promulgate a criterion that is either more or less stringent than a criterion derived under the standard procedures in ch. NR 105, Wis. Adm. Code. The approach selected for deriving the PFOS standard is based on the department’s data analysis which shows that fish consumption is the dominant exposure route of concern for PFOS. The department selected a method that allowed correlation with fish consumption advisories, which would not be included in calculation under ch. NR 105, Wis. Adm. Code. Also, with regard to the calculation of PFOA criteria, the department’s calculated criteria are more protective of children that ingest or consume PFOA contaminated water compared to the procedures under ch. NR 105, Wis. Adm. Code. Finally, codifying a method for developing PFOS and PFOA minimization plans will reduce the administrative burden and permitting timelines that would have been associated with processing a large volume of variance requests expected as a result of the criteria developed using the procedures outlined ch. NR 105, Wis. Adm. Code. The department believes that public health-based criteria combined with PFOS and PFOA minimization plans will result in more timely reductions in levels of PFOS and PFOA. The department expects that the selected approach will be effective at reducing sources of PFOS and PFOA in areas of the state where PFOS or PFOA concentrations in wastewater are elevated.
7. If Held, Summary of Comments Received During Preliminary Comment Period and at Public Hearing on the Statement of Scope:
The department received written comments related to the scope statement for WY-23-19 from 49 entities during the scope statement comment period, and verbal comments from 5 speakers during the public hearing on the statement of scope. Of the comments received, 38 entities expressed support of the proposed rules, 8 expressed opposition to the proposed rules, and the opinions of the remaining 8 were mixed. Those expressing mixed opinions voiced general support for the rulemaking effort but noted concerns about the cost of implementation, the desire to regulate PFAS as a class rather than compound by compound, technical issues with the toxicity values developed by the Department of Health Services, and regulation of PFOS and PFOA at the source rather than at POTWs.
8. Comparison with Similar Rules in Adjacent States:
The administrative codes of adjacent states contain narrative criteria for the protection of surface waters, although none of the adjacent states’ narrative criteria are specific to PFOS or PFOA. The narrative criteria of Illinois, Iowa, and Michigan specifically prohibit concentrations of toxic substances in surface waters in amounts that will adversely affect human health or public health. Minnesota’s narrative criteria prohibits discharge of wastes in such quantities that will cause pollution as defined by law.
Code citations for these narrative criteria are as follows:
— Illinois: Ill. Admin. Code tit. 35, § 302.210: “Other Toxic Substances. Waters of the State shall be free from any substances or combination of substances in concentrations toxic or harmful to human health, or to animal, plant or aquatic life. Individual chemical substances or parameters for which numeric standards are specified in the Subpart are not subject to this Section.” — Iowa: IAC § 567.61.3(2)(d): “General water quality criteria. The following criteria are applicable to all surface waters including general use and designated use waters, at all places and at all times for the uses described in 61.3(1) ‘a.’ … ‘d.’ Such waters shall be free from substances attributable to wastewater discharges or agricultural practices in concentrations or combinations which are acutely toxic to human, animal, or plant life.”
— Michigan: R 323.1057, Mich. Admin. Code: “Rule 51. (1) Toxic substances shall not be present in the surface waters of the state at levels that are or may become injurious to the public health, safety, or welfare, plant and animal life, or the designated uses of the waters. As a minimum level of protection, toxic substances shall not exceed the water quality values specified in, or developed pursuant to, the provisions of subrules (2) to (4) of this rule or conditions set forth by the provisions of subrule (6) of this rule. A variance to these values may be granted consistent with the provisions of R 323.1103.”
— Minnesota: Minn. Stat. 7050.0210-13: “Pollution prohibited. No sewage, industrial waste, or other wastes shall be discharged from either a point or a nonpoint source into the waters of the state in such quantity or in such manner alone or in combination with other substances as to cause pollution as defined by law. In any case where the waters of the state into which sewage, industrial waste, or other waste effluents discharge are assigned different standards than the waters of the state into which the receiving waters flow, the standards applicable to the waters into which the sewage, industrial waste, or other wastes discharged shall be supplemented by the following: The quality of any waters of the state receiving sewage, industrial waste, or other waste effluents shall be such that no violation of the standards of any waters of the state in any other class shall occur by reason of the discharge of the sewage, industrial waste, or other waste effluents.”
Two adjacent states – Michigan and Minnesota – have released numeric water quality values for PFOS, or PFOS and PFOA. Both states developed their values according to the procedures outlined in 40 CFR 132, but each state used different inputs which resulted in different numeric values. Similarly, Wisconsin selected a different methodology and different inputs, as described in Section 9 below, and thus the proposed standards are different. Further, Minnesota released site-specific criteria (SSC) for PFOS rather than implementing the criteria statewide. Michigan has calculated statewide values as Wisconsin is proposing to do. Wisconsin chose not to pursue the development of SSC for this rulemaking effort. Over the past several years, the department has endeavored to collect data on the occurrence of PFAS across the state, and this data indicates the possibility of human exposure to PFOA and PFOS via surface waters or fish taken from surface waters in areas throughout the state. With statewide criteria the department seeks to provide protection for citizens’ use of all waters. Additionally, Minnesota’s code includes provisions for developing SSCs without rulemaking, but Wisconsin’s statutory framework require rulemaking for SSCs. Thus, there would be no administrative time saved or expedited human health protections gained by developing SSCs compared to statewide criteria. Wisconsin’s proposed standard of 8 ng/L for PFOS is slightly more stringent than Michigan’s value of 11 ng/L and, compared to Minnesota’s PFOS criterion in waters where it applies, less stringent than Minnesota’s criterion of 0.05 ng/L. Wisconsin’s proposed standards of 20 ng/L and 95 ng/L for PFOA in public drinking water supply waters and non-public drinking supply waters, respectively, are more stringent than Michigan’s values of 420 and 12,000 ng/L for PFOA in drinking and non-drinking waters, respectively. The primary reason for the significant difference between Michigan’s PFOA criteria and Wisconsin’s PFOA criteria is that the reference dose (maximum amount of toxic substance that can be consumed to avoid public health impacts) that Michigan used in its calculations (conducted in 2011) is higher and not based on the most recent science. Furthermore, the bioaccumulation factor (BAF) that Michigan used in its PFOA calculation was experimentally derived based on laboratory data while the department used actual field measured fish tissue and water sampling data from surface waters for its PFOA calculations. Federal regulations state that field measured data should be used if available. Finally, Michigan used adult-specific exposure factors (body weight and water ingestion rates) rather than the child-specific factors that the department used. This difference is discussed below in more detail as well as in the technical support document.
