In 2010 the EQB enacted extensive changes to DEP’s NPDES regulations, now codified at Chapter 92a. Among these changes was a revision to a previous requirement to apply for a new NPDES permit whenever significant changes to influent pollutant loadings—either the addition of a new pollutant or a substantial increase in an existing pollutant—was projected to occur. The new regulation, now at § 92a.24(a), is a bit less stringent and states, in part:
[A]ny change of wastestream, that may result in [a] an increase of pollutants that have the potential to . . . violate effluent limitations specified in the permit, or [b] that may result in a new discharge, or [c] a discharge of [i] new or [ii] increased pollutants for which no effluent limitation has been issued, must be approved in writing by the Department before the permittee may commence the new or increased discharge, or change of wastestream. The Department will determine if a permittee will be required to submit a new permit application and obtain a new or amended permit before commencing the new or increased discharge, or change of wastestream. [Internal enumeration added for clarity.]
The NPDES permit provides these reporting requirements in Section A.III.C.2. However, several provisions of the permit appear to conflict with the regulation. Inquiries of DEP permitting staff in regard to these anomalies during permit reissuance negotiations did not result in any clarification. Additionally, one POTW reported to me that it had submitted a request for approval of new and increased pollutants to the regional DEP office, and was told by that office that DEP does not issue written approvals for changes to wastestream.
As a result of growing concern about compliance with the permit provisions, in 2018 I wrote to Mr. Sean Furjanic, DEP’s Environmental Program Manager, asking a number of specific questions. Mr. Furjanic kindly responded to the questions in writing and also replied to a follow-up letter I sent in October. This article is a summary of my questions and DEP’s official responses; because of space limitations, not all issues raised in the letters are discussed here. Unless shown in quotation marks, the “DEP Responses” below are my syntheses or summaries of Mr. Furjanic’s statements. Because DEP’s responses were provided by a senior official, I believe that they constitute Department policy and can be relied on in interpreting and applying the NPDES permit conditions discussed. Please note that this article only addresses issues relevant to POTWs. Some provisions that apply to industrial direct dischargers were not discussed with DEP and may have different policy issues.
In addition to issues regarding reporting planned changes, I also asked about DEP’s policies regarding reporting changes in influent pollutants that are not planned but are discovered after the fact—a situation that is not covered by either the regulation or the permit. DEP’s responses on this issue are also discussed below.
Issue 1—Reporting “new” pollutants: This issue has two subparts.
A.) Definition. “New” pollutants are those that have not previously been detected in the influent, as reported in the most recent permit application. I asked if pollutants that were not tested for in the permit application process are also considered “new” pollutants for reporting and approval purposes?
DEP Response. Yes.
B.) Written Approval. Both the regulation and the Permit state that a POTW cannot accept the introduction of new pollutants unless it (i) reports the intent to accept the new pollutant, and (ii) receives written approval from DEP. I reported a case where the regional office staff refused to issue a written approval although they did communicate approval by telephone. I asked what a municipality is to do if DEP staff refuses to issue a written approval for the addition of new pollutants.
DEP Response. DEP did not respond to the question of what to do if the regional office staff does not respond in writing. DEP stated that it does not have a standard operating procedure for how to respond to a notice, but offered that when a request to accept a new pollutant is received, the regional office staff is supposed to: (1) approve the request in writing; (2) request additional information; (3) deny the request; or (4) request submission of an application to amend the NPDES permit to provide for the new pollutant (as provided in the regulation).
Discussion. If regional office staff does not respond in writing to a request to accept a new pollutant, the POTW is in a difficult position, since it may have to notify a local industry that it cannot accept the waste, or risk a permit violation by allowing the industry to proceed and accepting the new pollutant without DEP’s permission. I suggest that if this situation arises, the municipality consult with counsel as to its options.
Issue 2—Reporting Planned Increases In Existing (“Approved”) Pollutants. The permit introduces the term “approved” pollutants and defines it to mean any pollutant that has been detected and reported to DEP (usually in the permit application), regardless of whether or not there is a permit limit. To determine if a pollutant is “approved,” the POTW should consult the influent and effluent testing data provided in the most recent permit renewal application. As noted below, it may be beneficial to summarize these influent loading data on a separate record for future reference.
There are several inconsistencies between the permit and the regulation regarding “approved” pollutants. DEP provided clarification of these issues, which I have divided into two main topics: when to report, and how permission is obtained.
A.) Determining when to report increases. The regulation requires reporting planned increases of approved pollutants under only two conditions: (i) if an effluent limit violation could result, or (ii) if there is no effluent limit in the permit. The permit includes the first of these criteria and adds three additional ones, which appear to be intended to address the second one (which is not actually stated in the permit). The added permit criteria are: (iii) if the proposed increase in mass loading is more than 20% of the maximum loading reported in the last permit application; (iv) if the increase could cause “pass through or interference”; and (v) if the increase would result in a violation of “water quality standards.” I questioned the addition of reporting criteria not in the regulations and, perhaps of more concern, how POTWs are to determine if any of these criteria apply. The five reporting criteria are discussed separately below.
(i) Effluent Violation. I asked how a POTW could decide if a proposed increase in pollutants from an industry or hauler might result in an effluent limit violation.
DEP Response. DEP stated that POTWs may use the “20% rule,” discussed below, as a heuristic method of evaluating the potential to cause an effluent limit violation. (See quoted response under (iii) below.) However, DEP cautions that POTWs are still required to report any planned increase that they think may result in an effluent violation, regardless of whether the 20% rule applies (if, for instance, the current effluent concentrations of the pollutant are very close to the limit). Therefore POTWs would be well advised to estimate the effects on their own and if there is any question, report the planned increase to DEP for further evaluation.
(ii) Increased Pollutants With No Effluent Limit. As noted above, this regulatory criterion is not stated in the permit. However, DEP indicated that the “20% rule” (discussed next) is intended to provide guidance for meeting the regulatory requirement to report all planned increases of pollutants with no effluent limits. However, since this is implied, not stated, POTWs might consider reporting all planned increases in pollutants with no effluent limits, no matter how small, so that they are in full compliance with the regulation.
(iii) 20% Increase. I asked how this criterion relates to the two regulatory reporting criteria for increases in “approved” pollutants.
DEP Response. “DEP has established a notification standard in permits of a 20% cumulative increase for approved pollutants to assist permittees in implementing the provisions in [the regulation] relating to ‘. . . increased pollutants for which no effluent limitation has been issued.’ This 20% standard also applies to pollutants with an effluent limitation . . . .”
Discussion. The “20% rule” provides a numerical criterion that should make deciding what to report easier. POTWs should keep the influent data from their most recent permit application available so that the maximum influent loading of existing pollutants reported in that document can be compared to any proposed increases. The reporting form for planned increases—DEP Form 3800-FM-BCW0482 —requires reporting both the average and maximum influent loading of that pollutant as reported in the last permit application. The Instructions for the form only reference the 20% increase standard; there is no mention of the other permit criteria for existing pollutants. This appears to confirm DEP’s statement that the 20 % rule can be used—with discretion—to evaluate all of the other criteria for reporting increases of existing pollutants.
Also, note the reference to “cumulative” loading. If prior increases less than 20% have already occurred during the five year permit cycle, a subsequent small increase might exceed the 20% cumulative reporting requirement. Thus, a POTW with an active industrial user base may wish to create a spreadsheet of all pollutants being accepted and documenting when increases occur and the magnitude of each one.
(iv) Pass through and interference
(a) Definition. Not all POTWs are familiar with the terms “pass through” and “interference.” I suggested that the definitions of the terms, as they appear in the EPA pretreatment regulations (40 CFR § 403.3(k) and (p)), be included in the Permit.
DEP Response. DEP agrees and plans to do so.
(b) Application. The EPA definitions require that a permit violation—not necessarily an effluent limit violation—must result from an event in order for it to be considered pass through or interference. Thus, this criterion is similar to, but somewhat broader than, the effluent limit violation criterion in the regulation and the 20% rule can be used with appropriate discretion.
DEP Response. DEP agrees.
(v) Exceedance of water quality standards. The fourth reporting criterion in the permit for increases in pollutants appears nowhere in the regulation. I asked how POTWs are supposed to evaluate it, since only DEP has the tools to evaluate effluent impacts on receiving water quality. I suggested that since POTWs do not have the ability (or obligation) to compute appropriate effluent limits to maintain water quality standards, that all proposed pollutant increases of any magnitude be reported so that DEP can make that determination.
DEP Response. “The use of the 20% notification standard as discussed above is intended to eliminate the need for a permittee to determine whether the increased loading of pollutants may cause an exceedance of water quality standards. DEP does not expect permittees to perform fate and transport analyses [or] water quality modeling to determine the possible impact on the receiving waters. However, if the facility decides to do so anyway and determines that increased pollutant loading is likely to cause a violation of water quality standards . . . DEP would expect notification regardless of the amount of the increase. DEP will consider how this may be made clearer in the permit language. . . . Your proposal that DEP evaluate all increases of approved pollutants regardless of magnitude is legally appropriate but not practical given DEP’s resources.”
B.) Obtaining written permission. The regulation requires written permission from DEP before accepting any increase in pollutants that meets the regulation’s criteria. The permit, however, states that if DEP does not respond to a notice within 30 days, “the permittee may proceed with the increase in loading.” I asked how DEP reconciles these two apparently contradictory provisions.
DEP Response. “Where DEP does not reply to notification of a planned increase to pollutant loading within 30 days, DEP’s latest issued permit constitutes the written approval.”
Summary Discussion. Reviewing all of DEP’s responses to my questions about reporting increases in pollutants, and looking at the instructions for the reporting form, it appears that, except in unusual cases, POTWs can rely on the “20% rule” to determine if proposed increases in existing pollutants should be reported.
However, DEP agrees that there is no prohibition on reporting any and all proposed increases, even very small ones. Doing so places the burden of deciding whether an increase would cause an effluent limit violation or result in exceedance of a water quality standard on the agency with the tools (and responsibility) to make the determination—DEP. Hence, reporting every planned increase of any magnitude may be the most protective approach, especially in light of the “permit as shield” rule and DEP’s position that once a planned increase is reported, unless DEP actually denies the request the permit itself constitutes the “written permission” required by the regulation. (But remember that the 20% rule and the deemed approval do not apply to new pollutants.)
Issue 3. Reporting Unanticipated Changes Neither the DEP regulation nor the permit address the question of new or increased pollutants discovered after the fact, as may happen when an industrial discharger changes its processes without notifying the POTW. However, an EPA regulation (40 CFR §122.42(b)) does require reporting such changes. I asked how DEP wants POTWs to comply, especially since no mention of this regulatory requirement appears in the permit to advise POTWs of the requirements.
DEP Response. DEP agrees that the EPA regulations at 40 CFR §122.42(b) require notification of changes in the wastestream discovered after the fact. The obligation to report changes in waste streams would be triggered upon the permittee’s awareness of the change: “When discovered after the fact, DEP expects that the permittee will notify DEP within 45 days upon discovery, assuming notification criteria are met.” The report of discovered changes is to be made using the same form used for planned changes: form 3800-FM-BCW0482.
Discussion. The “notification criteria” mentioned in the response are assumed to be those in the EPA regulation: “a new introduction of pollutants . . . from an indirect [industrial] discharger . . . [or] any substantial change in the volume or character of pollutants being introduced into the POTW by a source introducing pollutants into the POTW at the time of issuance of the permit.” EPA does not define the term “substantial change,” but given DEP’s reliance on the “20% rule” for everything else, one might assume that DEP would define a “substantial change” using that criterion. Obviously, discovery of a new pollutant would be reported regardless of its magnitude.
Issue 4. Applicability Of § 92a.24 To “Discovered” New Or Increased Pollutants. I asked if the POTW reports “discovered” after-the-fact new or increased pollutants, is that a violation of the Permit (or the regulations) because the change was not reported by the POTW 45 days in advance and written permission obtained?
DEP Response No, but the POTW should have “mechanisms in place” to take enforcement action against an industrial user that fails to notify the POTW in advance of the change in its discharge.
Discussion POTWs with EPA-approved Industrial Pretreatment Programs should already be regulating their industrial users so that there are no surprises; other POTWs that accept industrial wastes might consider some sort of industrial monitoring program to try to avoid unexpected changes in pollutants being received. This will both protect the treatment plant and make it less likely that a permit violation can occur.
Final Note. This article does not explore every issue discussed in the correspondence. For instance, there are unanswered questions about the legality of including substantive requirements in NPDES permits that are not contained in the regulations. This article is intended to help POTWs understand the reporting requirements as they appear in their permits, as DEP has explained them. The entire correspondence (omitting, however, some of the attachments) is provided on Mette Evans & Woodside’s website (www.mette.com) under my link and can be reviewed in detail by anyone interested in these issues. You may also contact the author (firstname.lastname@example.org, 717.231-5215) to discuss any concerns or questions you may have. And, of course, you may wish to discuss these policies with your regional office staff so that everyone is in agreement as to what is required.
 The previous regulation at § 92.7 read, in part, “[Changes] which . . . do not violate effluent limitations . . . shall be reported . . . to the Department . . . . A new permit application shall be submitted and a new permit obtained before commencing new or increased discharge, or change in the wastestream, which would . . . include any new or increased pollutant not identified in a previous permit application.” [Emphasis added.] The latter provision appears to have rarely, if ever, been implemented.
 All of the letters are available on the Mette, Evans & Woodside website (www.mette.com) under my link.
 The Permit adds a requirement that the written notice be at least 45 days in advance and via certified mail.
 The regulation, permit, and reporting form also refer to exceeding “ELGs.” Effluent Limits Guidelines are direct discharge limits which only apply to certain categories of industrial discharger, never to POTWs, so they are not discussed in this article.
 Imposing enforceable permit requirements not provided for by regulation implicates legal principles beyond the scope of this article.
 Keep in mind that the criterion is mass loading, not concentration. Thus, the flows at the time that samples are obtained must be recorded.
 The Form is captioned “Planned Changes To Waste Stream Reporting Form” and is found under Wastewater Management/DMR Reports/DMR Supplemental Reports on the DEP website.
 To keep this article of manageable size, I have not included a discussion of this important rule. See discussion on page 10 of my July 12 letter introducing Question 6.