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Legal Authority to Include Non-Numeric Effluent Limitations or Best Management 

Practices (BMPs) in the Construction and Development Effluent Limitations Guidelines 

and New Source Performance Standards (February 15, 2012)

In the Construction and Development Effluent Limitations Guidelines and New Source 

Performance Standards (C&D Rule), codified at 40 CFR part 450, EPA is requiring active 

construction and development sites required to obtain NPDES permit coverage pursuant to 40 

CFR 122.26(b)(14)(x) and (b)(15) to implement non-numeric effluent limitations and best 

management practices (BMPs) to control and minimize the discharge of pollutants from their 

sites to surface waters. EPA estimates that compliance with the C&D Rule will significantly 

reduce the amount of sediment and other pollutants discharged from construction and 

development sites. Those other pollutants include nutrients, metals, and other toxic and 

nonconventional pollutants that may be naturally present in soils, and can be contributed during 

construction activity or by activities that occurred at the site before the construction activity. 

EPA’s legal authority to promulgate this regulation is found in section 301(b), section 304(e), 

section 306, section 308(a), section 402(a)(1)(B), section 402(a)(2) and section 501(a) of the 

Clean Water Act (CWA), 33 U.S.C. § 1251, et seq. EPA also relies on 40 C.F.R. § 122.44(k)(1), 

(2) and (4). 

EPA is authorized under CWA section 304(e) to publish regulations on a categorical basis for 

certain toxic or hazardous pollutants for the purpose of controlling plant site runoff, spillage or 

leaks, sludge or waste disposal, and drainage from raw material storage, when the Administrator 

determines (1) that such incidents are associated with or ancillary to the industrial manufacturing 

or treatment process of point sources within the class or category, and (2) that the incidents may 

contribute significant amounts of toxic or hazardous pollutants to navigable waters. The BMPs 

in the C&D Rule are directed, among other things, at preventing or otherwise controlling or 

minimizing the presence and/or amount of metals discharged from the site, whether those metals 

occur naturally in the soil or were introduced during construction activity. Such metals include 

copper, nickel, lead, and silver, among many others, that are toxic pollutants pursuant to CWA 

section 307(a)(1). In addition, construction sites may contain oils or other hazardous substances 

designated under section 311 of the CWA. For this reason, the Administrator has determined 

that runoff of such metals is associated with or ancillary to construction activity and that failure 

to prevent or control such discharges could contribute significant amounts of toxic or hazardous

pollutants to navigable waters. See also 40 CFR § 122.44(k)(1) (“In addition to the conditions 

established under § 122.43(a), each NPDES permit shall include conditions meeting the 

following requirements when applicable ... (1) Authorized under section 304(e) of the CWA for 

the control of toxic pollutants and hazardous substances from ancillary industrial activities.”).

The BMPs established in the C&D Rule will control and minimize the toxic and/or hazardous

effects of discharges of these pollutants. As the U.S. Court of Appeals for the D.C. Circuit 

observed after reviewing the goals of the CWA and its legislative history, “The indications are 

abundant that EPA was intended to possess broad latitude in identifying and regulating suspected 

toxics.” NRDC v. EPA, 822 F.2d 104, 118 (D.C. Cir. 1987)(upholding EPA regulation requiring 

information in permit applications regarding effluent characteristics); see Statement of Sen. 

Muskie (Dec. 15, 1977), 95th Cong., 2d Sess., reprinted in A Legislative History of the Clean 
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Water Act of 1977, Vol. 3, at 453-54 (1978) (citing a spill of mirex to illustrate need for § 304(e) 

authority, even though mirex is not designated as a § 307(a) toxic pollutant or a § 311 hazardous 

substance). Courts have also upheld EPA’s authority to issue BMPs, e.g., Citizens Coal 

Council v. US EPA, 447 F.3d 879, 895-96 (6th Cir. 2006)(finding best management practices 

within the statutory definition of “effluent limitation” as a restriction of discharges) citing 

NRDC, Inc. v. EPA, 673 F.2d 400, 403 (D.C. Cir. 1982). 

For authority to impose BMPs on construction and development sites required to obtain NPDES 

permit coverage under 40 CFR 122.26(b)(14)(x) and (b)(15), EPA also relies on sections 402(a) 

and 501(a) of the CWA and 40 C.F.R. § 122.44(k)(3) and (4) of EPA’s regulations. Under 

section 402(a)(1), the Administrator is authorized to issue a permit “upon condition that [the] 

discharge will meet either all applicable requirements under sections 301, 302, 306, 307, 308, 

and 403 of this Act, or prior to the taking of necessary implementing actions relating to all such 

requirements, such conditions as the Administrator determines are necessary to carry out the 

provisions of this Act.” EPA’s authority to establish permit conditions under this section is very 

broad. See NRDC v. Costle, 568 F.2d 1369, 1380 (D.C. Cir. 1977). As applied in this context, 

section 402(a)(1) authorizes EPA to establish controls on “any pollutant, or combination of 

pollutants,” for which EPA has not yet promulgated effluent limitations guidelines or standards 

under sections 301 or 306 that would be applicable to the permittee in question. Given the lack 

of numeric effluent limitations guidelines or standards, BMPs are necessary to carry out the 

provisions of the Act. In addition, section 402(a)(2), read in concert with section 501(a), 

authorizes EPA to prescribe as wide a range of regulatory permit conditions as the Agency 

deems appropriate in order to assure compliance with applicable effluent limits. (Section 501(a) 

authorizes the Administrator to carry out her functions through regulation.) EPA has determined 

that active construction sites without an adequate BMP program consistent with the C&D Rule 

will discharge levels of sediment, nutrients, metals and other pollutants associated with active 

construction that would not reflect the level of control representing the Best Available 

Technology Economically Achievable (BAT) and Best Available Demonstrated Control 

Technology (BADT) for New Source Performance Standards (NSPS) required by the CWA.

EPA’s regulations at 40 C.F.R. § 122.44(k)(2) expressly authorize BMPs to control or abate the 

discharge of pollutants when authorized under section 402(p) for the control of stormwater 

discharges. EPA has historically controlled stormwater through the use of BMPs in its general 

permits covering active construction. EPA also heavily relies on non-numeric effluent 

limitations and BMPs in controlling other “wet weather” discharges, such as those applicable to 

municipal separate storm sewer systems and industrial stormwater. Further, EPA’s regulations at 

40 C.F.R. § 122.44(k)(4) specifically authorize permit writers to impose, when applicable, BMP 

permit conditions to control or abate the discharge of pollutants in any case when “[t]he practices 

are reasonably necessary to achieve effluent limitations and standards or to carry out the 

purposes and intent of [the] CWA.” 40 C.F.R. § 122.44(k)(4). In this case, EPA has determined 

that the BMPs in the C&D Rule are reasonably necessary to carry out the purposes and intent of 

the CWA. The stated goals of the CWA are “to restore and maintain the chemical, physical, and 

biological integrity of the Nation’s waters” and “that the discharge of pollutants into the 

navigable waters be eliminated by 1985”. See CWA section 101(a) and 101(a)(1). To that end, 

section 301(b)(2)(A) requires establishment of effluent limitation guidelines for a category or 

class representing best available technology economically achievable “which will result in 
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reasonable further progress toward the national goal of eliminating the discharge of all 

pollutants.” And section 306 requires new source performance standards reflecting best 

available demonstrated control technology that requires, where practicable, a standard 

“permitting no discharge of pollutants.” EPA has determined that the BMPs in the C&D Rule, 

by preventing, controlling, and/or minimizing the discharge of stormwater from active 

construction sites, are necessary to meet that statutory requirement. And EPA has determined 

that the BMPs in the C&D Rule are also reasonably necessary to carry out the purposes and 

intent of the CWA and hence are authorized under, among other legal authorities discussed 

above, 40 CFR § 122.44(k)(4).

Although a requirement to establish and implement BMPs of the type described in the C&D Rule

could be imposed on a case-by-case basis under authority of section 402(a)(1) and 40 C.F.R. § 

122.44(k)(2) and (4), EPA has decided to promulgate the requirement on a categorical basis for

active construction sites required to obtain permit coverage pursuant to 40 CFR § 

122.26(b)(14)(x) and (b)(15) under section 304(e) and under its broad authority conferred by 

section 501(a). As discussed above, section 304(e) expressly authorizes EPA to promulgate 

BMPs by regulation on a categorical basis. In addition, section 501(a) authorizes the 

Administrator to prescribe such regulations as are necessary to carry out her functions under the 

Act. EPA has determined that the BMPs specified in part 450 are necessary to ensure that each

active construction site required to obtain NPDES coverage prevent, control, and/or minimize the 

discharge of pollutants from its site to waters of the U.S. While the BMP regulation is intended 

to provide considerable flexibility to active construction sites in designing their BMPs, EPA has 

determined that the various BMPs specified in the regulation represent the BAT and BADCT 

level of control. By codifying them into a regulation of general applicability, EPA intends to 

promote expeditious implementation of such BMPs and to assure uniform and fair application of 

the baseline requirements across the country. EPA also believes that the regulation represents an 

appropriate and efficient use of its technical expertise and resources that, when exercised at the 

national level, will relieve state permit writers of the burden of implementing this aspect of the 

CWA on a case-by-case basis. Thus, in order to ensure that minimal BMP requirements are in 

place for active construction sites nationwide required to obtain NPDES permit coverage, and to 

promote efficient administration of the NPDES permit program, EPA has promulgated BMPs for

such active construction sites in the C&D Rule. 

EPA also relies on Section 308(a) as authority to require active construction sites required to 

obtain NPDES permit coverage to develop and implement the BMPs prescribed in the C&D 

Rule. Section 308(a) authorizes EPA, among other things, to require owners or operators of 

point sources to establish and maintain records, make reports, install, use and maintain 

monitoring equipment, sample effluent, and provide such other information as the Administrator 

may require in order to carry out the objectives of the Act. Among other things, EPA expects 

that the permitting authority may be able to use such information to monitor active construction 

sites’ compliance with the permit’s (based on the C&D Rule’s) BMP requirements. See Sections 

308(a)(2) and 402(a)(2).