STATE OF MINNESOTA MINNESOTA POLLUTION CONTROL AGENCY

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2 ATTACHMENT 1 STATE OF MINNESOTA MINNESOTA POLLUTION CONTROL AGENCY IN THE MATTER OF THE DECISION TO REISSUE THE MINNESOTA NATIONAL POLLUTANT DISCHARGE ELIMINATION SYSTEM/STATE DISPOSAL SYSTEM CONSTRUCTION STORMWATER GENERAL PERMIT MNR FOR THE DISCHARGE OF STORMWATER ASSOCIATED WITH CONSTRUCTION ACTIVITY. FINDINGS OF FACT CONCLUSIONS OF LAW AND ORDER The above entitled matter came before the Minnesota Pollution Control Agency (MPCA) Citizens Board at a regular meeting held in St. Paul, Minnesota on June 25, Based on the MPCA staff review, comments and information received during the comment period, and other information in the record of the MPCA, the MPCA hereby makes the following,, and Order: FINDINGS OF FACT GENERAL BACKGROUND 1. This matter involves the proposed reissuance of National Pollutant Discharge Elimination System (NPDES)/State Disposal System (SDS) Construction MNR (Permit) for discharge of stormwater associated with construction activity (appended hereto as Attachment 2). The MPCA must decide under applicable statutes and rules whether to reissue the Permit. 2. The MPCA is required to regulate pollutants associated with discharges from construction activity pursuant to the federal Clean Water Act at 33 U.S.C. 1342(p) and rules adopted by the U.S. Environmental Protection Agency (EPA) found at 40 CFR pt (a)(9). State law authorizes the MPCA to regulate stormwater discharges through rules and general permits. Minn. Stat , subd. 5c. 3. Pollutants associated with the discharge of untreated stormwater include sediment, phosphorus, nitrogen, bacteria, metals, inorganics, pesticides, construction chemicals, debris, petroleum products and volatile organic chemicals. However, even if stormwater is successfully treated to remove pollutants, its uncontrolled discharge can also cause deleterious impacts to aquatic habitats and indirect pollution. The uncontrolled discharge of stormwater can cause scouring and erosion in streams and rivers (which in turn can cause the release of sediment and other pollutants located in the sediment), and changes to stream morphology disruptive to the ecology of aquatic plant and animal communities. The uncontrolled discharge of stormwater to wetlands can result in degradation of the function of the wetland and its aquatic biota. 4. The MPCA, as the state s NPDES/SDS permitting authority, has issued NPDES/SDS general permits for discharges of stormwater associated with construction activity since This Permit has been reissued every 5 years since 1993 with the last reissuance of this Permit in 2008.

3 5. The MPCA has adopted rules which incorporate the terms of this Permit by reference (Minn. R ) and which establish who is required to apply for the Permit and application procedures (Minn. R ), and certain exceptions. 6. In 2009, the EPA adopted the rule titled Effluent Limitations Guidelines and Standards for the Construction and Development Point Source Category Rule found at 40 CFR pt. 450 (C&D Rule). This rule established effluent guidelines for stormwater discharge permits applicable to construction activity. Delegated states that issue construction stormwater permits must incorporate these provisions into their construction stormwater permits and the EPA has the authority to review and make objections or recommendations to the state s proposed permits (40 CFR ). The MPCA was authorized and delegated by the EPA in 1974 to administer the NPDES program (40 CFR ). The EPA approved the MPCA's NPDES general permit program on December 15, The MPCA s current general permit regulating stormwater discharges associated with construction activity expires on August 1, 2013, and must be reissued if the MPCA intends to allow most construction activity to be regulated in this manner. To ensure that the Permit conforms to the new federal requirements, the MPCA must update the Permit to comply with the standards established at 40 CFR pt The MPCA is also revising the Permit to clarify existing language, better align with the Municipal Separate Storm Sewer Systems (MS4) program, address defects in the existing general permit, and incorporate changes needed to enhance compliance with the Permit. More detail on the changes that the MPCA staff proposed for this Permit is found in the Public Notice published in the State Register February 4, 2013, and in the detailed fact sheet outlining changes to the draft Construction, both documents are located on the MPCA Construction Stormwater web page. 8. One change was made to the Permit to comply with a new state statute found at Minn. Stat , subd. 5(c)(c). This state statute (which is referred to as the Minimal Impact Design Standards or MIDS legislation), requires the MPCA to enable and promote low impact development and stormwater management techniques for post construction. Pursuant to this statute, the MPCA has incorporated into this Permit a requirement that, unless prohibited or, infeasible (for example, in the case of lack of right of way on linear projects), construction projects be designed to ensure that at least one inch of water volume generated by new impervious surfaces is permanently managed by infiltration or other volume reduction practices. Further discussion of this issue can be found in the discussion of Volume Management Requirement starting at finding number As in the past, this Permit will address pollution associated with the discharge of stormwater related to construction activity by requiring each Permittee to develop and implement a Stormwater Pollution Prevention Plan (SWPPP) in compliance with the Permit, prior to applying for coverage under the Permit or conducting any construction activity. The Permit contains specific detailed content requirements and standards for the Best Management Practices (BMPs) and other elements of the SWPPP. The SWPPP will allow each Permittee to choose the appropriate BMPs to address the potential discharge of sediment and other potential pollutants from the construction site, and to control the indirect pollution and degradation of surface waters that 2

4 could result from the uncontrolled discharge of increased volumes of stormwater from the new impervious surfaces. PROCEDURAL HISTORY 10. The MPCA provided public stakeholders initial information on the Permit reissuance at a stakeholder meeting held on December 17, The stakeholder meeting was scheduled to facilitate the public in seeking clarification and understanding of the proposed reissuance of the Permit. 11. In accordance with the requirements of Minn. R and Minn. R , subp. 4, the MPCA prepared a draft Permit and gave the public an opportunity to comment. The draft Permit was publicly noticed for a 45 day period from February 4, 2013, to March 20, Notice of intent to reissue the general Permit and for the public comment period was placed in Volume 37, Number 32 of the State Register on February 4, This notice and the draft Permit were placed on the MPCA s Public Notice website on February 4, In addition, interested and affected parties were notified via the Agency s GovDelivery listserve. 13. A comment period of 45 days was provided. 14. A second public informational meeting was held on March 8, 2013, 32 days into the comment period, in order to clarify and answer questions on the permit language, leaving time for the stakeholders to finalize comments. 15. Additionally, the MPCA went before the MPCA Citizen s Board on March 26, 2013, to present the reissuance of the Permit as an Informational Item. At this meeting, the Board heard testimony from certain interested persons about issues of concern. 16. The MPCA received 57 written comment correspondences during the 45 day comment period. The comment letters are provided in Appendix A. The MPCA reviewed each of the comments and provided a detailed response to each. All comments are summarized and responses are provided in Appendix B to these findings, which is incorporated into these findings as the MPCA s rationale for its response to the comment. The MPCA did not receive any requests for a contested case hearing. 17. Many of the commenters suggested changes to the language of the permit to clarify and improve the permit. In many cases, the MPCA changed the language of the permit as suggested by the commenter. In other cases, the MPCA declined to change the language of the permit as suggested for a variety of reasons, including the need to maintain consistency with the language in the federal C&D Rule or concerns arising out of state law. Below, the MPCA will discuss and respond to the major issues of concern raised by commenters. 3

5 GENERAL ISSUES RAISED BY COMMENTERS/MPCA RESPONSE Environmental Protection Agency; Construction & Development Rule 18. Many comments expressed concern over whether the MPCA s permit would conform to changes that the EPA has noticed its intent to make to the 2009 Effluent Limitations Guidelines and Standards for the Construction and Development Point Source Category (C&D) Rule, found at 40 CFR pt. 450, as a result of litigation involving the C&D Rule. 19. The MPCA has looked at the changes that the EPA has proposed to make and does not believe that any changes to the MPCA s permit are necessary, as noted in more detail at Part A Environmental Protection Agency; Construction & Development Rule in the Responses to Comment document (Appendix B). In general, the MPCA s proposed permit either addresses the change that the EPA has proposed or will not make the proposed change for reasons arising out of state law. The MPCA is aware that there are ongoing negotiations and potential future revisions to this federal rule, but the MPCA must issue permits that are in compliance with existing federal rules, not predict what may be in future rulemaking or the outcomes of legal challenges. The one exception to the C&D Rule changes involves the numeric turbidity limits and monitoring requirements that were promulgated by the EPA. The EPA notified states by publication in the Federal Register (Volume 78, No.62, Monday, April 1, 2013) that states are no longer required to incorporate the numeric turbidity limits and monitoring requirements found at 40 CFR (a)(b) into NPDES permits because the numeric limitation was stayed. Volume Management Requirement 20. Many commenters expressed concern over the requirement for permanent on site volume control for runoff from new impervious surfaces. The concerns raised went to the feasibility of such controls on certain sites, to calculation methods, to different efforts under way to develop standards, and an argument that MPCA should delay implementation of a volume control standard until more study is completed. Some commenters questioned the MPCA s authority to require volume control within this permit. 21. The MPCA finds that the discharge of stormwater from impervious surfaces created by construction activities even if treated to remove contaminants can have deleterious impacts on the environment and that such impacts meet the definition of water pollution under state statute, Minn. Stat , subd. 13(b). The MPCA notes that the definition of water pollution under state law is broader than pollutant as defined under federal law (see 33 U.S.C. 1362(6)), and that the MPCA has the authority to issue permits in order to prevent, control or abate water pollution. Minn. Stat , subd. 1(c). The MPCA has specific authority to issue general permits to control storm water discharges. Minn. Stat , subd. 5c. State policy is to promote the retention and conservation of water. Minn. Stat. 103A.205; Minn. Stat c (c). Federal cases that suggest that EPA has limited authority to control volumes of water as a surrogate for sediment pollutant limits in a TMDL are not relevant to this question. See Virginia DOT v. EPA, 2013 WL (January 3, 2013)(EPA required to regulated pollutants directly not through surrogate measures). 22. The MPCA finds that as impervious surfaces increase, so do impacts to the natural environment as wetlands and streams are inundated with water that degrades their natural functions. Secondary 4

6 water pollution can result from the increased discharge to the surface water as the result of scour and bank erosion. The MPCA also notes that even stormwater treated as required under this permit contains residual levels of pollutants that can have cumulative impacts on the environment. The MPCA finds that, where treatment through infiltration is possible, it is reasonable to require such treatment rather than discharge even low levels of pollutants. 23. The MPCA finds that it is required and authorized to include volume control in the permit as a result of federal and state non degradation rules (40 CFR ; Minn. R ) and because the Minimal Impact Design Standard legislation does indicate that the MPCA shall develop tools to enable and promote the implementation of low impact development. The MPCA believes that this permit is such a tool. Minn. Stat c(c). 24. The MPCA finds that it is feasible on most sites to implement volume control methods, based on its study of such methods and on the experience of local units that have already implemented volume control methods within their jurisdictions. The MPCA has calculated the volume control requirement included in this permit to be consistent with the scientific evidence that has emerged from its efforts to develop such a standard for mimicking natural hydrology as required by Minn. Stat c(c). The MPCA sees no reason to delay implementation of the volume control requirement through this permit because certain studies are still in progress. The MPCA finds that the scientific evidence in support of volume control methodologies is adequate at this time to support implementation. The permit does not mandate certain models or methodologies to be used, but instead will allow designers to make use of any model or calculation that is supported by reasonable engineering practices. The MPCA has included conditions in the permit that address certain concerns raised by commenters, in particular the concern that infiltration will lead to groundwater pollution. 25. The MPCA finds that the implementation of volume control will not result in excessive costs to permittees. Implementation of volume control is required only for the discharge related to new impervious surfaces and not existing impervious surfaces, i.e., the expanded discharges. While certain costs may increase as a result of the need to manage stormwater without a discharge, the MPCA notes that certain costs may also decrease, both for the owner of the construction activity and for governmental units that may otherwise have been required to maintain or upgrade stormwater conveyance systems as volumes increase. Such upgrades may be avoided if more water is managed on site. Inspection Frequency 26. A number of commenters expressed concern over the requirement in the proposed permit to conduct inspections after ¼ inch of rainfall, which is an increase from the current permit s requirement for inspections to be conducted after ½ inch of rainfall. These commenters requested that the MPCA retain the existing inspection requirement. 27. In response to these comments, the MPCA finds that it is reasonable to retain the current inspection requirement to inspect after ½ inch of rainfall. The MPCA did some additional research and concluded that about 35 percent of rainfall events exceed ¼ inch while 22 percent of events exceed ½ inch. Runoff from the ½ inch event is about 25 percent of the total runoff. The ¼ inch 5

7 event creates only about 10 percent of the runoff. Thus, by returning to the ½ inch inspection requirement, the number of inspections would decrease by almost half and only approximately 15 percent of the annual runoff volume would not be inspected. This would represent a considerable saving to permittees, while not significantly affecting oversight, and also ensuring proper function of BMPs. As a result, the MPCA proposes to drop the requirement for inspections after ¼ inch rainfall events, hereby retaining the 2008 requirement, which necessitates inspections at least once every 7 days and within 24 hours after a rainfall event greater than ½ inch. Rain Gauge Requirement 28. A number of commenters expressed concern over the proposal in the draft permit to require permittees to employ a rain gauge on the construction site to determine when rainfall events trigger the inspection requirement. Several commenters requested that Part IV.E.2.e of the permit be amended so that a rain gauge would not have to be installed on every site. One commenter would like to use an official rain gauge if located within a certain distance (one suggested 3 miles) of the site or a representative rain station. The Minnesota Department of Natural Resources would like to use fire weather stations or predictions. One commenter suggested the use of weather notification companies. One commenter requested guidance on linear projects and where to place gauges. One commenter wanted the ability to use regional weather data. These weather reporting systems have been shown to have accuracies comparable to a physical rain gauge. 29. Based on these comments, the MPCA finds that it would be reasonable to provide alternatives to the proposed site rain gauge. The MPCA has modified the language to allow the use of a rain gauge on site or within one mile of the project, and to allow permittees to use a weather reporting system that provides site specific rainfall data from radar summaries. CONCLUSIONS OF LAW 30. General permits are authorized by the EPA for use by NPDES delegated states under 40 CFR The MPCA is specifically authorized to issue a general permit to any category of point source stormwater discharges by Minn. Stat , subd. 5c (2012). The MPCA has established standards and procedures for the issuance of general permit in Minn. R Pursuant to Minn. R , the MPCA concludes that a general permit is appropriate to regulate discharges associated with construction activity because: A. There are several permit applicants or potential permit applicants who have the same or substantially similar operations, emissions, activities, discharges, or facilities. B. The permit applicants or potential permit applicants discharge, emit, process, handle, or dispose of the same types of waste. C. The operations, emissions, activities, discharges, or facilities are subject to the same or substantially similar standards, limitations, and operating requirements. 6

8 D. The operations, emissions, activities, discharges, or facilities are subject to the same or substantially similar monitoring requirements. The MPCA specifically finds that all construction activity involves substantially similar processes that disturb and expose topsoil and that result in discharges of sediment and other pollutants associated with construction. Because the pollutants associated with construction activity are substantially similar regardless of the size and location of the construction activity, substantially similar standards, limitations, and operating requirements and monitoring requirements can be imposed on all construction activities subject to the Permit on a statewide basis. Any person who does not want to conform to the terms and conditions of this proposed general permit may apply for an individual permit by filing an application as provided in Minn. R. ch The MPCA has the authority to require an individual permit be obtained if the particular activities and discharges of the permittee have characteristics creating the potential for significant environment effects or the permittee has not been in compliance with the terms of the general permit and applicable statutes and rules. 32. Adequate and timely public notice of the permit reissuance was given in accordance with Minn. R and The requirements of Minn. R for issuance of a Permit have been met. The MPCA finds that the proposed permittees will, with respect to the facility or activity to be permitted, comply with all applicable state and federal pollution control statutes and rules administered by the agency, and conditions of the permit, and that all applicable requirements of Minn. Stat. ch. 116D, and the rules adopted under Minn. Stat. ch. 116D, have been fulfilled. The permit contains conditions necessary for the permittee to achieve compliance with applicable Minnesota or federal statutes or rules, and conditions that the MPCA has determined are necessary to protect human health and the environment. 34. Any findings that might properly be termed conclusions and any conclusions that might properly be termed findings are hereby adopted as such. 7

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