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NPDES Storm Water Phase II Program to Local Governments

Reply to: James C. Gulick or Mary Penny Thompson Environmental Division Tel: (919) 716-6600 Fax: (919) 716-6766

January 11, 2002

Coleen Sullins, Water Quality Section Chief Bradley Bennett, Stormwater and General Permits Unit Supervisor Division of Water Quality 1617 Mail Service Center Raleigh, NC 27699-1617

Re: Advisory Opinion: Application of the NPDES Storm Water Phase II Program to Local Governments; N.C. Gen. Stat. § 214.7; N.C. Admin. Code tit. 15A, r. 2H.0126; 33 U.S.C. § 1342(p); 40 C.F.R. §§ 122.26, 122.32, 123.35

Dear Coleen and Bradley:

You requested written advice on two questions concerning the State implementation of the federal National Pollutant Discharge Elimination System (“NPDES”) Storm Water Phase II Program as it relates to local governments. The questions arose from a request by the North Carolina Association of County Commissioners to review the federal rule and determine whether State implementation would require a county to obtain a permit, notwithstanding the county does not own or directly operate the largest storm water conveyance system in its jurisdiction, i.e., the State road system and its associated drainageways.1 In particular, you asked (1) whether a county may be required to obtain a NPDES Storm Water Phase II permit for the storm water conveyances within its jurisdiction notwithstanding that it does not own or operate roads and associated drainageways; and (2) if a county is required to obtain a permit, what permitting avenues would be available.

In regard to the first Issue our answer is “yes;” we conclude that there are four scenarios under which a county may be required by DENR to obtain a Phase II permit, notwithstanding that it does not own or operate roads and associated drainageways. The four scenarios arise when: (a) the county owns or operates a municipal separate storm sewer system (“MS4")2 in an

1 Letter from Ed Reg an, Dep uty Direc tor of the N orth Caro lina Assoc iation of C ounty C omm issioners to Bradley Bennett of the North Carolina Department of Environment and Natural Resources’ Division of Water Quality dated September 27, 2000.

2 Under either phase, “municipal separate storm sewer” means a conveyance or system of conveyances including road s with drainage sy stems, mun icipal streets, catch basins, curbs, gutters, ditche s, man-m ade chann els, or storm drains ow ned by a public b ody de signed o r used for collecting o r conve ying storm water w hich is not a combined sewer or p ublicly owned treatment works. 40 C .F.R. § 122.26(b)(8).

urbanized area which discharges directly to receiving waters; (b) the county owns or operates a storm water conveyance in an urbanized area which is interconnected with a permitted MS4, but retains the authority to implement a measure of the program; (c) the State designates a county’s MS4 as needing a permit, regardless of location; or (d) a third party successfully petitions the State to require county permitting. In response to the second Issue, if required to obtain a Phase II permit, a county may obtain a general permit, an individual permit or arrange to be copermittees with existing or new permittees.

Issue 1. The NPDES storm water permitting program has two phases, Phase I for large and medium MS4s3 and Phase II for smaller MS4s4. Phase II permits require implementation of a storm water management program which is composed of six minimum measures. The minimum measures consist of (1) public education; (2) public notice; (3) illicit discharge detection and elimination; (4) construction controls; (5) post-construction controls; and (6) pollution prevention. In certain instances, only the county may be able to implement one or more of these six minimum measures. One such example of municipal control over a minimum measure is the requirement of post-construction controls, i.e., requiring maintenance of installed best management practices after construction is complete. To this end, a county may exercise control over its jurisdiction through the land use authorities granted to it by statute. Counties have broad authority to regulate and restrict the size of buildings; the percentage of lots occupied, the size of open spaces; the density of population; the location and use of buildings, structures, and land for trade, industry, residence or other purposes; and provide density credits or severable development rights for dedicated rights-of-way. N.C. Gen. Stat. § 153A-340. Counties may adopt zoning regulations designed to facilitate the adequate provision of water, sewerage and other public requirements. N.C. Gen. Stat. § 153A-341. Counties also regulate subdivisions by ordinance. N.C. Gen. Stat. § 153A-330 et seq.

North Carolina is one of the few states in which roads and adjoining drainageways are owned and operated by the state’s department of transportation5 rather than by counties. Apparently for this reason, the Association of County Commissioners has questioned whether a county may be required to obtain a Phase II permit when a county does not own or operate the majority of storm water conveyances, namely road drainageways, in its municipal jurisdiction, despite their ability to implement the minimum measures contemplated under Phase II. However, it is our opinion that North Carolina counties may be required by DENR to obtain a permit under at least four scenarios, notwithstanding that they do not own or operate the majority of MS4s in their jurisdiction.

3 Phase I covered discharges from M S4s serving populations of 100,000 or m ore. 33 U.S.C. § 1342(p)(2).

4 Phase II covers discharges from MS4s serving populations of less than 100,000.

5 North Carolina currently regulates NC DOT storm water under a statewide NPDES Stormwater Phase I permit (NPDES Permit No. NCS00 0250).

First, a county may be required by DENR to obtain a permit for any discrete system which it owns or operates in an urbanized area.6 Road drainageways are not the only MS4s in a county. Counties own or operate jail facilities, hospital complexes, municipal buildings, maintenance facilities and parks which contain catch basins, ditches, storm drains and other features of storm drainage which discharge directly to waters of the State without passing through another storm system such as NC DOT’s road system. These MS4 point sources must obtain Phase II permits to discharge storm water directly to waters of the State.

Second, a county may be required by DENR to obtain a permit when its storm water devices are interconnected in an urbanized area with a permitted MS4 and the county retains authority to implement one or more of Phase II’s six minimum measures. Under Phase I, the permitting agency could include storm water conveyances that did not themselves constitute a large or medium MS4 under the permit for a large or medium MS4 due to the interrelationship between the discharges of the smaller system and the MS4, including the physical interconnections between the storm sewers and other factors. 40 C.F.R. §§ 122.26(b)(4) and (7). DENR issued a statewide NPDES Phase I permit to the NC DOT for its roadways, but did not require counties to be permitted at that time. Without the county as a co-permittee, NC DOT’s Phase I permit fails to provide program coverage outside of the right-of-way although those areas contain storm water conveyances that drain to the right-of-way.

Third, a county may be required by DENR to obtain a permit when the State permitting authority designates it for coverage, even if it falls outside of an urbanized area. 40 C.F.R. §§ 122.32(a)(2) and 123.35(b). The rule’s preamble discusses this extended coverage by indicating that “Permitting authorities may also decide to designate all MS4s within a county or township, if they believe it necessary to protect water quality.” 64 Fed. Reg. 68751. As the NPDES permitting authority, DENR is required to develop a process, as well as criteria, to designate small MS4s outside of the urbanized area which have the potential to result in exceedances of water quality standards or other significant water quality impacts. 40 C.F.R. § 123.35(b). Other significant water quality impact criteria may consist of discharge to sensitive waters, high growth or growth potential, high population density, contiguity to an urbanized area, significant contributor of pollutants to waters, and ineffective protection of water quality by other programs. 40 C.F.R. § 123.35(b)(1)(ii). DENR may also designate any small MS4 that contributes substantially to the pollutant loadings of a physically interconnected MS4 that is regulated by the NPDES storm water program. 40 C.F.R. § 123.35(b)(4). Therefore, even if a county lies outside an urbanized area or is only physically interconnected with another regulated MS4, it may be required to obtain a Phase II permit through the State’s own designation process.

Fourth, a county may be required by DENR to obtain a permit when it is subject to a successful third party petition. Even if DENR itself does not designate a county as needing a

6 The Bu reau of C ensus de termine s urbaniz ed areas b ased up on the lates t decenn ial census d ata. Appendix 6 of the Phase II rule lists 25 counties which are partially or fully located within an urbanized area.

Phase II permit, third parties may petition the permitting agency to do so. 40 C.F.R. §§ 122.26(f)(4) and 122.32(b). Under the petition process, any operator of a permitted MS4 may petition DENR to require a separate NPDES permit for a discharge entering the operator’s MS4. 40 C.F.R. § 122.26(f)(1)(emphasis added). Moreover, any person may petition DENR to require a county to obtain an NPDES permit for a storm water discharge which contributes to a violation of a water quality standard or is a significant contributor of pollutants to receiving waters. 40

C.F.R. §§ 122.26(f)(2) (emphasis added).

The Phase II rule generally focuses on discharges from MS4s which, by definition, requires the county to own or operate the MS4.7 However, the language of the rule addressing the Phase II petition process addresses “any discharge into [an MS4].”8 This change in language creates some ambiguity as to the scope of coverage. In particular, it might be argued by the petitioning operator of a permitted MS4 that he must only show that the discharge reaches its system, not that the discharge comes from another MS4. The petition process also addresses “[any] discharge which is composed entirely of storm water which contributes to a violation of a water quality standard or is a significant contributor of pollutants to waters of the United States.”9 In this instance, it might be contended that the third party must show that the discharge negatively affects water quality, without a requirement that the third party must show that the discharge emanates from an MS4.

It may be contended that the general intent of the statute would support such a construction. The structure of the CWA and its history indicate that all point sources should be permitted. See Natural Resources Defense Council (NRDC) v. Train, 396 F. Supp. 1393 (D.D.C. 1975), affirmed, NRDC v. Costle, 568 F.2d 1369 (D.C. Cir. 1977). With the adoption of the Water Quality Act of 1987, Congress amended the CWA and added section 402(p), which established the priorities, deadlines and permit requirements for storm water point sources, including MS4s. 33 U.S.C. § 1342(p).

The Phase II rule implements the Clean Water Act goal by seeking to provide comprehensive coverage of storm water control and to eliminate gaps in storm water coverage. As the rule’s preamble states, “‘Donut holes’ are gaps in program coverage where a small unregulated MS4 is located next to or within a regulated larger MS4 that is subject to an NPDES permit under the Phase I NPDES storm water program. The existence of such ‘donut holes’ creates an equity problem because similar discharges may remain unregulated even though they cause or contribute to the same adverse water quality impacts. Using NPDES permits to regulate the unregulated discharges in these areas is intended to facilitate the development of a seamless

7 See 40 C.F.R . §§ 122 .26(b)(4 ), (7), (8), and (16).

8 See 40 C.F.R. §§ 122.26(f)(1).

9 See 40 C.F.R . § 122.2 6(f)(2). Also see 33 U.S.C. § 1342(p)(2)(E).

regulatory program for the mitigation and control of contaminated storm water discharges in an urbanized area.” 64 Fed. Reg. 68739. The rule’s preamble dedicates an entire subsection, Section II.H., to describing the municipal role in Phase II. 64 Fed. Reg. 68748 through 68771. The rule’s appendix goes on to identify twenty-five North Carolina counties as being fully or partially located within an urbanized area. 64 Fed. Reg. 68822. It appears that EPA anticipated that North Carolina counties would be covered by the Phase II program and did not anticipate that whole areas would be left out simply because NC DOT rather than local government maintained the road system. Thus, the petition process may extend county coverage to county storm water discharges regardless of whether the discharge emanates from a conveyance that is owned and operated by the county and otherwise meets the definition of a small MS4.

Issue 2. If a county is required to obtain a NPDES permit under Phase II, it has several permitting options. It may request a general permit for all systems and components within the county boundaries. The Phase II program encourages the use of general permits on a systemwide or jurisdiction-wide basis. Under Phase I, NC DOT received a system-wide permit for its road system. Under Phase II, a county could receive a jurisdiction-wide permit for the systems within the county. In this regards, an NPDES general permit can cover a category of dischargers within a defined geographic area which may be defined broadly to include political boundaries, e.g., an entire county. 64 Fed. Reg. 68739. For the storm water systems which interconnect with NC DOT road systems, a county could join NC DOT as a co-permittee in its Phase I permit which would have to be modified to include the Phase II minimum measures. The Phase II rule allows a newly regulated MS4 to join as a “limited” co-permittee with a regulated MS4 by referencing a common storm water management program. 64 Fed. Reg. 68739. A “limited” copermittee is only responsible for the measures not covered by the already-existing permit. Alternatively, a county could obtain its own Phase II permit for the systems that interconnect with NC DOT. Finally, a county may obtain or require individual permits for each system within its geographical area.

We trust this analysis proves helpful. If you have any questions or wish to discuss this

matter further, please do not hesitate to contact us. With best wishes, we are Very truly yours,

James C. Gulick Senior Deputy Attorney General

Mary Penny Thompson Assistant Attorney General