Proposed NPDES General Permits

Background

The Clean Water Act prohibits the discharge of a pollutant into the navigable waters of the United States without a permit, specifically an NPDES permit. Under the Clean Water Act, discharges from certain animal feeding operations that occur under certain rainfall conditions are subject to a narrow exemption from the NPDES regulations for Concentrated Animal Feeding Operations (CAFOs). See §3.0, p 16 of EPA’s 1995 Guide Manual on NPDES Regulations for Concentrated Animal Feeding Operations, EPA 833-B-95-001 (December 1995) (hereinafter “EPA’s 1995 CAFO Guide Manual”).

According to 40 CFR 122, Appendix B, an animal feeding operation is not a CAFO if it discharges only in the event of a 25-year, 24-hour storm. See §3.1, p. 16 of EPA’s 1995 CAFO Guide Manual. 40 C.F.R. §411 defines a 25-year, 24-hour rainfall event as a rainfall event with a probable recurrence interval of once in twenty-five years as defined by the National Weather Service in Technical Paper Number 40, “Rainfall Frequency Atlas of the United States”, May 1961, and subsequent amendments, or equivalent regional or State rainfall probability information developed therefrom. In most of eastern North Carolina, this event is 5, 6 or 7 inches, depending on the precise location. This exemption applies to all feedlots, including CAFOs designated as such on a case by case basis. Id.

According to EPA’s 1995 CAFO Guide Manual,

The effluent guidelines for feedlots [40 CFR 412], and consequently NPDES permits for CAFOs, also contain references to catastrophic and chronic rainfall. A catastrophic event is equivalent to a 25-year, 24-hour storm event. Catastrophic events could include tornadoes, hurricanes, or other catastrophic conditions that would cause an overflow from the required water retention structure. A chronic rainfall is a series of wet weather conditions that preclude dewatering of properly maintained waste retention structures [58 F.R. 7620]. Under the current effluent limitations guidelines for CAFOs, permitted discharges that result from chronic rainfall or catastrophic events do not violate the CWA. Unpermitted discharges other than those due to the 25-year, 24-hour storm, however, would not be authorized because, absent a permit, a discharge is a violation of the CWA.

Id. (Emphasis added).

N.C.G.S. §143-215.10A-M and N.C.G.S. §143-215.1(a)(12) prohibit the discharge of pollutants to waters of the State from animal waste management systems except as authorized by a permit from the EMC. See, N.C.G.S. §143-215.10C(a). 15A NCAC 2H .0100 prohibits the unpermitted construction or operation of an animal feeding operation (AFO) above certain threshold units and, therefore, prohibits the unpermitted discharge of pollutants from CAFOs. State permits adopted pursuant to N.C.G.S. §143-215.10A-M prohibit the discharge of wastewater from permitted CAFOs to waters of the State except as may result because of rainfall from a storm event more severe than the 25-year, 24-hour storm. N.C.G.S. §143-215.10C(b).

On October 8, 2001, EPA approved a modification of DENR’s National Pollutant Discharge Elimination System (NPDES) permitting program, delegated under the Federal Water Pollution Control Act (Clean Water Act, hereinafter “CWA”), 33 USC §§1251 to 1387, to allow the Environmental Management Commission to issue NPDES general permits for animal feeding operations.

Discussion – Part I

In our opinion, the General Assembly intentionally crafted the language in N.C.G.S. §143-215.10C(b) to insure that it would not only be consistent with, but more stringent than, the federal NPDES requirements for CAFOs.

N.C.G.S. § 143-215.10C(b) specifically provides that “[a]n animal waste management system shall be designed, constructed, and operated so that the animal operation served by the animal waste management system does not cause pollution in the waters of the State except as may result because of rainfall from a storm event more severe than the 25-year, 24-hour storm.” (Emphasis added).¹ Under N.C.G.S. § 143-215.10C(b), in order for any pollution in waters of the state from a CAFO to be excused, that pollution must have (1) resulted because of (2) rainfall from a storm event (3) more severe than the 25-year, 24 hour storm.

As you know, EPA has expressed concern that the “more severe than” language is less stringent than the “chronic, catastrophic causes for an overflow and the runoff from a 25-year, 24hour rainfall event” language in the 40 C.F. R. § 412 effluent guidelines. In particular it has been suggested that the term “severe” is subjective, whereas the phrase “greater than the 25-year, 24-hour storm”, as used in the state’s current non-discharge permits for animal feeding operations, is a finite measure of quantity.

We disagree that the term “more severe than” means something different from “greater than.” “Severe” is defined in the American Heritage Dictionary as “Extremely intense: severe pain; a severe storm.” “More” means “greater in number” or “greater in size, amount, extent or degree.” “Great” is defined as “extremely large in size” and as “remarkable or outstanding in magnitude or degree.” “Greater” is, of course, a comparative form of the adjective “great.” In the context of the 25-year, 24-hour storm, “more severe” connotes if it does not denote, “greater.” Thus, “greater than the 25year, 24-hour storm” can reasonably be and in our opinion must be interpreted to have the same meaning as “more severe than the 25-year, 24-hour storm.”²

¹ As you know from other discussions, all waters of the United States subject to the CWA in North Carolina are a subset of waters of the State. See, N.C.G.S. § 143-212(6).² N.C.G.S. §143-215.211 states the intent of the General Assembly that the powers and duties of the Environmental Managem ent Comm ission be construed to enable it to administer federal programs such as the NPDES program. It seems clear to us among other things that the statute should not be interpreted in any way that would jeopardize the

It is axiomatic that a storm event in which more rain falls within a 24-hour period than during the 25-year 24-hour storm is more severe than the 25-year, 24-hour storm. On the other hand, if no more rain occurs during such a storm event than during the 25-year, 24-hour storm, then it cannot be more severe. This very fact would appear to make clear that the General Assembly intended to make the State law more stringent than the federal regulation, in which “catastrophic event” is defined as being “equivalent” to the 25-year, 24-hour storm.³

In our opinion, the “more severe than” language in §143-215.10C(b) must be interpreted in light of the probability element inherent in the definition of the 25-year, 24-hour storm. We believe that the General Assembly’s use of this standard reflected its concern to use an objective standard in which the likelihood (i.e., statistical probability) of the amount of rainfall occurring in a storm event was a pivotal factor. If a rain event exceeds 24 hours’ duration, the severity of the rainfall must continue to be measured in terms of that probability element. Thus, a single storm event of a period longer than 24-hours’ duration, with more rainfall altogether than the 25-year, 24-hour storm but with less rainfall within any given 24-hour period, could still be “more severe than the 25-year, 24-hour storm,” provided that the amount of rainfall at the facility during that event was greater than the amount that had a probable recurrence interval of once every twenty-five years, as demonstrated by proper statistical analysis of rainfall data for the geographical area in question.

We note that the phrase “a storm event” in §143-215.10C(b) is stated in the singular. We interpret this to restrict the exception to pollution resulting because of rainfall during a single storm event. We also note that DENR currently relies in other contexts upon the best professional judgment (BPJ) number used for research applicable to the Southeastern United States by the National Oceanic and Atmospheric Administration, under which a single storm event may contain intervals up to 10 consecutive hours of no precipitation. Especially with this in mind, it is fair to say that it is common knowledge that rainstorm events exceeding 24 hours duration take place in North Carolina. As a result, we conclude that “a storm event” referred to in the statute could exceed 24 hours in length but could not contain intervals without rain exceeding 10 hours. In any case, this standard retains greater objectivity, and we believe is necessarily more stringent than the standard of “a chronic rainfall,” which is defined by EPA to be “a series of wet weather conditions that preclude dewatering of properly maintained waste retention structures [58 F.R. 7620].”⁴

Last, in order for there to be a lawful excuse for a pollutant discharge under N.C.G.S. §143-215.10C(b), the contribution of improper design, construction or operation to the pollutant discharge must be excluded, because the statute clearly requires that the amount of rainfall during the storm event be established as the cause of the pollution. This, too, is consistent with the Clean Water Act requirements as implemented by EPA.

From all of this it follows that consistent with N.C.G.S. 143-215.10C(b) no permit terms can

delegatio n of the N PDES program to the State. T o do so w ould be contrary to legislative in tent.
³ EPA’s 1 995 CA FO Gu ide Ma nual.
⁴ EPA’s 1995 CAFO G uide Manual

excuse a discharge of pollution to waters except as may result because of rainfall from a storm event more severe than the 25-year, 24-hour storm.

Discussion – Part II

The language in the draft permit, at Part I(1), provides as follows:

Facilities which are designed, constructed and operated to contain all waste plus the runoff from a 25-year, 24-hour rainfall event for the location of the facility and which are in compliance with their Certified Animal Waste Management Plan (CAWMP); the Clean Water Act (Act), and its implementing regulations; and this permit, which unintentionally have a discharge [of] waste as a result of a storm event more severe than the 25-year, 24-hour storm, will not be considered to be in violation of this permit. The storm event under which a discharge would be allowable must also meet all criteria as established in EPA effluent guidelines for swine facilities (40 C.F.R. Part 412).

The last sentence in the language quoted above might be construed to allow the catastrophic and chronic rainfall exemption in the proposed permit, inconsistent with North Carolina’s more stringent statutory language. To be consistent with the statute, that last sentence should be deleted. In addition, we believe that DENR has authority to define the parameters of intentional, controlled discharges, or bypasses, as a proper response to a storm event more severe than the 25-year, 24-hour storm under circumstances where they prevent more catastrophic failure. Therefore, the word “unintentional” could and perhaps should be deleted from the previous clause of this provision. ⁵

One example of alternative language that would make the permit language consistent would be as follows:

Facilities must be designed, constructed and operated to contain all waste plus the runoff from a 25-year, 24-hour rainfall event for the location of the facility; must be in compliance with their Certified Animal Waste Management Plan (CAWMP); the Clean Water Act (Act), and its implementing regulations; and this permit, so that the animal operation served by the animal waste management system does not cause pollution in the waters of the State except as may result because of rainfall from a storm event more severe than the 25-year, 24-hour storm.

SECOND ISSUE

Your second issue relates to the EPA’s proposed regulation that may require the Department

⁵ See discussion of the Third Issue, below.

to co-permit entities that exercise substantial operational control over CAFOs along with the owner/operator of the facility. The issue is most pertinent to the swine industry where integrators own the animals raised and exercise various degrees of control over the actions taken at the facilities. You ask if the Department may require such entities be to be co-permittees on the NPDES general permits for CAFOs, and if so, under what conditions of control.

In our opinion, any entity, including an integrator, that exercises substantial operational control over CAFOs and the owner/operator of the animal operation such that it can fairly be determined to be “constructing or operating” an animal waste management system, can be included as a required co-permittee on the NPDES general CAFO permit. DENR has the existing authority to require co-permitting of integrators in the event that their operational control over is clearly established. DENR also has the authority to define the necessary indicia of control that establish operational control. Existing law already would require that persons exercising such control be included on a permit.

N.C.G.S. §143-215.10A-M and N.C.G.S. §143-215.1(a)(12) authorize the EMC to adopt, issue, reissue, modify, deny, revoke, and enforce reasonable permits, under such conditions as the agency may prescribe, for the prevention of water pollution and for the operation of animal waste management systems, disposal systems and other facilities, as required by 33 USC §1342 and 40 CFR Part 122. N.C.G.S. §143-215.10C(a) provides that “No person shall construct or operate an animal waste management system for an animal operation without first obtaining an individual permit or a general permit under this Article.”

“Person” is defined in N.C.G.S. §143-212(4) to include “individuals, firms, partnerships, associations, institutions, corporations, municipalities and other political subdivisions, and governmental agencies.” “Integrator” is defined by law to mean “a person, other than a grower, who provides 250 or more animals to a swine farm and who either has an ownership interest in the animals or otherwise establishes management and production standards for the permit holder for the maintenance, care and raising of the animals.” N.C.G.S. §143-215.10H(a)(3).

The question, then is when does an integrator’s exercise of operational control reach the point where the integrator can fairly be said to “operate” the animal waste management system.

Indicia of control over an animal feeding operation would include owning the animals, providing or mandating specific food for the animals and providing for the animals’ medical treatment. While an integrator potentially could fit the definition of such a person, it does not appear from the permitting statute that an integrator is required automatically to be a co-permittee as a result of having an ownership interest in swine and providing management and production standards for a swine farm.

Whether the degree of control and the relationship to the waste disposal practices at particular farms triggers co-permitting requirements should be examined further by the Department on a case by case basis. EPA’s subsequent regulatory guidance should also be taken into account in defining this relationship. We would be happy to work with DENR to that end.