UNITED STATES ENVIRONMENTAL PROTECTION AGENCY 

WASHINGTON, D.C. 20460 

AUG 14 1995 

OFFICE OF 

ENVIRONMENTAL AND COMPLIANCE ASSURANCE 

MEMORANDUM 

SUBJECT: National Policy Toxicity Regarding Whole Effluent Enforcement 

Robert Van Heuvelen, Director 

Office of Regulatory Enforcement 

Michael Cook, Director 

TO: 

Office of Wastewater Management 

Water Management Division Directors, Regions I-X 

Regional Counsels, Regions I-X 

State NPDES Directors 

The purpose of this joint memorandum is to clarify National 

policy with regard to the two most common issues raised by the 

regulated community involving the enforcement of whole effluent 

toxicity (WET) requirements in NPDES permits: 1) single 

exceedances of WET limits, and 2) inconclusive toxicity reduction 

evaluations (TRBs). 

Single Exceedances 

Section 309 of the Clean Water Act (CWA) states that any 

violation of a permit condition or limitation is subject to 

enforcement. Through EPA's "Enforcement Management System" (EMS) 

guidance, the EPA Regional or State enforcement authority is 

encouraged to initiate an appropriate enforcement response to all 

permit violations. 

to all parameters-- 

EPA's overall approach to enforcement applies 

once a facility has been identified as having 

an apparent permit violation(s), the permitting authority reviews 

all available data on the seriousness of the violation, the 

compliance history of the facility, and other relevant-facts to 

determine whether, to initiate an enforcement action and the type 

of action that is appropriate. The EMS recommends an escalating 

response to continuing violations of any parameter. 

EPA does a recommend that the initial response to a single 

exceedance of a WET limit, causing no known harm, be a formal 

enforcement action with a civil penalty. The "Whole Effluent 

Toxicity Basic Permitting Principles and Enforcement Strategy" 
2 

issued by the office of Water on January 25, 1989 states that any 

violation of a WET limit is of concern and should receive an 

immediate, professional review. It does not necessarily require 

that a formal enforcement action be taken--the enforcement 

authority has discretion on selecting an appropriate response. 

Guidance on enforcement responses to WET violations was 

added to the EMS in 1989. For example, EPA's recommended 

response to an isolated or infrequent violation of a WET limit, 

causing no known harm, is issuance of a letter of violation or an 

Administrative Order (AO), which does not include a penalty. As 

with violations of any parameter, the EMS recommends an 

escalating enforcement response to Continuing violations of a WET 

limit. 

The regulated community has expressed concern about the 

potential for third party lawsuits-for single exceedances of WET 

limits. Citizens cannot sue a permittee on the basis of a single 

violation of a permit limit. Under § 505(a) of the CWA, citizens 

are allowed to take a civil action against anyone who is alleged 

"to be in violation" of any standard or limit under the CWA. In 

Gwaltney of Smithfield. Ltd. v . . Chesapeake Bay Foundation. Inc. 

484 U.S. 49, 108 S.Ct. 376, 98 L.Ed.2d 306 (1987), the Supreme 

Court held that the most natural reading of "to be in violation" 

is @Ia requirement that citizen-plaintiffs allege a state of 

either continuous or intermittent violation--that is, a 

reasonable likelihood that a past polluter will continue to 

pollute in the future." 

Inconclusive TREs 

The 1989 "Whole Effluent Toxicity Basic Permitting 

Principles and Enforcement Strategy" states on page 9: 

"In a few highly unusual eases where the permittee has 

implemented an exhaustive TRE plan, applied appropriate 

influent and effluent controls, maintained compliance with 

all other effluent limits, compliance schedules, monitoring, 

and other permit requirements, but is still unable to attain 

or maintain compliance with the toxicity-based limits, 

special technical evaluation may be warranted and civil 

penalty relief granted. Solutions in these cases could be 

pursued jointly with expertise from EPA and/or the States as 

well as the permittee." 

EPA is committed to providing technical support in the 

"highly unusual cases" described above and is in the process of 

determining the number of facilities nationwide that fit in this 

category. As the WET program has grown and evolved, sources for 

this type of technical support have shifted to EPA Regions, 

States, and Tribes. In a conference call with Regional permits 

and enforcement staff in April and feedback from the annual 
3 

Biological Advieory Committee in May, the Regione,requeeted 

support from Headquarters in helping to establish national WET 

technical expertise to address issues such as inconclusive TRBs. 

There has been a national mechanism for this type of support in 

the past, as a complement to Regional and State/Tribal efforts 

(e.g., the National Effluent Toxicity Assessment Center). A 

national*vehicle for this type of effort is currently being 

evaluated with a view toward providing additional support for the 

national WET program. 

EPA believe8 that the science behind the WET program and 

test procedures is sound and continually improving, and fully 

supports the mid-course evaluations that are being planned and 

executed through an upcoming WET workshop,.ae well as other 

planned or ongoing studies. The September 1995 workshop is being 

organized by the Society for Environmental Toxicology and 

Chemistry (SETAC) as part of their Pellston workshop series, 

through partial funding frqm EPA and other groups. The purpose 

of the workshop is to assess where we are'in the WET program-- 

i.e., identify technical issues that have been resolved and need 

no further work as well as explore associated technical issues 

that do need further research, clarification, or resolution. 

Because participation in the workshop is by invitation only, an 

open forum will be held soon after the workshop to discuss,the 

results with all interested parties. 

Please call us or have your staff call Kathy Smith (ORB) at 

202-564-3252 or Donna Reed (OWM) at 202-260-9532 if you have any 

questions regarding this matter. 

cc: Tudor Davies (OST) 

NPDES Branch Chiefs, Regions I-X