Tenn. Comp. R. & Regs. 0400-40-14-.07
For the purpose of this rule:
Any WWF receiving wastes from an Industrial User to which a categorical Pretreatment Standard(s) applies may, at its discretion and subject to the conditions of this rule, grant removal credits to reflect removal by the WWF of pollutants specified in the categorical Pretreatment Standard(s). The WWF may grant a removal credit equal to or, at its discretion, less than its consistent removal rate. Upon being granted a removal credit, each affected Industrial User shall calculate its revised discharge limits in accordance with subparagraph (d) of this paragraph. Removal credits may only be given for indicator or surrogate pollutants regulated in a categorical Pretreatment Standard if the categorical Pretreatment Standard so specifies.
A WWF is authorized to give removal credits only if the following conditions are met:
The WWF applies for, and receives, authorization from the Approval Authority to give a removal credit in accordance with the requirements and procedures specified in paragraph (5) of this rule.
The WWF demonstrates and continues to achieve consistent removal of the pollutant in accordance with paragraph (2) of this rule.
The WWF has an approved pretreatment program in accordance with and to the extent required by this chapter; provided, however, a WWF which does not have an approved pretreatment program may, pending approval of such a program, conditionally give credits as provided in paragraph (4) of this rule.
The granting of removal credits will not cause the WWF to violate the local, State and Federal Sludge Requirements which apply to the sludge management method chosen by the WWF. Alternatively, the WWF can demonstrate to the Approval Authority that even though it is not presently in compliance with applicable Sludge Requirements, it will be in compliance when the Industrial User(s) to whom the removal credit would apply is required to meet its categorical Pretreatment Standard(s) as modified by the removal credit. If granting removal credits forces a WWF to incur greater sludge management costs than would be incurred in the absence of granting removal credits, the additional sludge management costs will not be eligible for EPA grant assistance. Removal credits may be made available for the following pollutants.
The granting of removal credits will not cause a violation of the WWF's permit limitations or conditions. Alternatively, the WWF can demonstrate to the Approval Authority that even though it is not presently in compliance with applicable limitations and conditions in its NPDES permit, it will be in compliance when the Industrial User(s) to whom the removal credit would apply is required to meet its categorical Pretreatment Standard(s), as modified by the removal credit provision.
Revised discharge limits for a specific pollutant shall be derived by use of the following formula:
y=x/(1-r)
where:
x=pollutant discharge limit specified in the applicable categorical Pretreatment Standard
r=removal credit for that pollutant as established under paragraph (2) of this rule (percentage removal expressed as a proportion, i.e., a number between 0 and 1)
y=revised discharge limit for the specified pollutant expressed in same units as x)
"Consistent Removal" shall mean the average of the lowest 50 percent of the removal measured according to subparagraph (b) of this paragraph. All sample data obtained for the measured pollutant during the time period prescribed in subparagraph (b) of this paragraph must be reported and used in computing Consistent Removal. If a substance is measurable in the influent but not in the effluent, the effluent level may be assumed to be the limit of measurement, and those data may be used by the WWF at its discretion and subject to approval by the Approval Authority. If the substance is not measurable in the influent, the data may not be used. Where the number of samples with concentrations equal to or above the limit of measurement is between 8 and 12, the average of the lowest 6 removals shall be used. If there are less than 8 samples with concentrations equal to or above the limit of measurement, the Approval Authority may approve alternate means for demonstrating Consistent Removal. The term "measurement" refers to the ability of the analytical method or protocol to quantify as well as identify the presence of the substance in question.
Influent and effluent operational data demonstrating Consistent Removal or other information, as provided for in subparagraph (a) of this paragraph, which demonstrates Consistent Removal of the pollutants for which discharge limit revisions are proposed. This data shall meet the following requirements:
The data shall be representative of yearly and seasonal conditions to which the WWF is subjected for each pollutant for which a discharge limit revision is proposed.
The data shall be representative of the quality and quantity of normal effluent and influent flow if such data can be obtained. If such data are unobtainable, alternate data or information may be presented for approval to demonstrate Consistent Removal as provided for in subparagraph (a) of this paragraph.
Where composite sampling is not an appropriate sampling technique, a grab sample(s) shall be taken to obtain influent and effluent operational data. Collection of influent grab samples should precede collection of effluent samples by approximately one detention period. The detention period is to be based on a 24-hour average daily flow value. The average daily flow used will be based upon the average of the daily flows during the same month of the previous year. Grab samples will be required, for example, where the parameters being evaluated are those, such as cyanide and phenol, which may not be held for any extended period because of biological, chemical or physical interactions which take place after sample collection and affect the results. A grab sample is an individual sample collected over a period of time not exceeding 15 minutes.
The sampling referred to in parts 1. through 4. of this subparagraph and an analysis of these samples shall be performed in accordance with the techniques prescribed in 40 CFR part 136 and amendments thereto. Where 40 CFR part 136 does not contain sampling or analytical techniques for the pollutant in question, or where the Director determines that the 40 CFR part 136 sampling and analytical techniques are inappropriate for the pollutant in question, sampling and analysis shall be performed using validated analytical methods or any other applicable sampling and analytical procedures, including procedures suggested by the WWF or other parties, approved by the Director.
All data acquired under the provisions of this paragraph must be submitted to the Approval Authority. Removal for a specific pollutant shall be determined either, for each sample, by measuring the difference between the concentrations of the pollutant in the influent and effluent of the WWF and expressing the difference as a percent of the influent concentration, or, where such data cannot be obtained, Removal may be demonstrated using other data or procedures subject to concurrence by the Approval Authority as provided for in subparagraph (a) of this paragraph.
For pollutants which are not being discharged currently (i.e., new or modified facilities, or production changes) the WWF may apply for authorization to give removal credits prior to the initial discharge of the pollutant. Consistent removal shall be based provisionally on data from treatability studies or demonstrated removal at other treatment facilities where the quality and quantity of influent are similar. Within 18 months after the commencement of discharge of pollutants in question, consistent removal must be demonstrated pursuant to the requirements of paragraph (2) of this rule. If, within 18 months after the commencement of the discharge of the pollutant in question, the WWF cannot demonstrate consistent removal pursuant to the requirements of paragraph (2) of this rule, the authority to grant provisional removal credits shall be terminated by the Approval Authority and all Industrial Users to whom the revised discharge limits had been applied shall achieve compliance with the applicable categorical Pretreatment Standard(s) within a reasonable time, not to exceed the period of time prescribed in the applicable categorical Pretreatment Standard(s), as may be specified by the Approval Authority.
A WWF required to develop a local pretreatment program by Rule 0400-40-14-.08 may conditionally give removal credits pending approval of such a program in accordance with the following terms and conditions:
Any WWF that wants to give a removal credit must apply for authorization from the Approval Authority.
An application for authorization to give removal credits (or modify existing ones) shall be submitted by the WWF to the Approval Authority.
A WWF may apply for authorization to give or modify removal credits at any time.
An application for authorization to give removal credits must be supported by the following information:
A list of pollutants for which removal credits are proposed.
The data required pursuant to paragraph (2) of this rule.
Proposed revised discharge limits for each affected subcategory of Industrial Users calculated in accordance with subparagraph (1)(d) of this rule.
A certification that the WWF has an approved local pretreatment program or qualifies for the exception to this requirement found at paragraph (4) of this rule.
A specific description of the WWF's current methods of using or disposing of its sludge and a certification that the granting of removal credits will not cause a violation of the sludge requirements identified in part 4. of this subparagraph.
A certification that the granting of removal credits will not cause a violation of the WWF's NPDES permit limits and conditions as required in part 5. of this subparagraph.
The Approval Authority shall review the WWF's application for authorization to give or modify removal credits in accordance with the procedures of Rule 0400-40-14-.11 and shall, in no event, have more than 180 days from public notice of an application to complete review.
Where the NPDES State has an approved pretreatment program, the Regional Administrator may agree in the Memorandum of Agreement under 40 C.F.R. § 123.24(d) to waive the right to review and object to submissions for authority to grant removal credits. Such an agreement shall not restrict the Regional Administrator's right to comment upon or object to permits issued to WWFs except to the extent 40 C.F.R. § 123.24(d) allows such restriction.
Once a WWF has received authorization to grant removal credits for a particular pollutant regulated in a categorical Pretreatment Standard it may automatically extend that removal credit to the same pollutant when it is regulated in other categorical standards, unless granting the removal credit will cause the WWF to violate the sludge requirements identified in part (1)(c)4. of this rule or its NPDES permit limits and conditions as required by part (1)(c)5. of this rule. If a WWF elects at a later time to extend removal credits to a certain categorical Pretreatment Standard, industrial subcategory or one or more Industrial Users that initially were not granted removal credits, it must notify the Approval Authority.
Once authority is granted, the removal credits shall be included in the WWF's NPDES Permit as soon as possible and shall become an enforceable requirement of the WWF's NPDES permit. The removal credits will remain in effect for the term of the WWF's NPDES permit, provided the WWF maintains compliance with the conditions specified in subparagraph (d) of this paragraph.
Following authorization to give removal credits, a WWF shall continue to monitor and report on (at such intervals as may be specified by the Approval Authority, but in no case less than once per year) the WWF's removal capabilities. A minimum of one representative sample per month during the reporting period is required, and all sampling data must be included in the WWF's compliance report.
The Approval Authority shall notify the WWF if, on the basis of pollutant removal capability reports received pursuant to subparagraph (c) of this paragraph or other relevant information available to it, the Approval Authority determines:
If appropriate corrective action is not taken within a reasonable time, not to exceed 60 days unless the WWF or the affected Industrial Users demonstrate that a longer time period is reasonably necessary to undertake the appropriate corrective action, the Approval Authority shall either withdraw such discharge limits or require modifications in the revised discharge limits.
The Approval Authority shall not withdraw or modify revised discharge limits unless it shall first have notified the WWF and all Industrial Users to whom revised discharge limits have been applied, and made public, in writing, the reasons for such withdrawal or modification, and an opportunity is provided for a hearing. Following such notice and withdrawal or modification, all Industrial Users to whom revised discharge limits had been applied, shall be subject to the modified discharge limits or the discharge limits prescribed in the applicable categorical Pretreatment Standards, as appropriate, and shall achieve compliance with such limits within a reasonable time (not to exceed the period of time prescribed in the applicable categorical Pretreatment Standard(s) as may be specified by the Approval Authority).
"Overflow" means the intentional or unintentional diversion of flow from the WWF before the WWF Treatment Plant. WWFs which at least once annually Overflow untreated wastewater to receiving waters may claim Consistent Removal of a pollutant only by complying with either subparagraph (a) or (b) of this paragraph. However, this paragraph shall not apply where Industrial User(s) can demonstrate that Overflow does not occur between the Industrial User(s) and the WWF Treatment Plant;
Allowances under this provision will only be granted where the WWF submits to the Approval Authority evidence that:
where:
rm=WWF's Consistent Removal rate for that pollutant as established under subparagraphs (1)(a) and (2)(b) of this rule
rc=removal corrected by the Overflow factor
Z=hours per year that Overflow occurred between the Industrial User(s) and the WWF Treatment Plant, the hours either to be shown in the WWF's current NPDES permit application or the hours, as demonstrated by verifiable techniques, that a particular Industrial User's Discharge Overflows between the Industrial User and the WWF Treatment Plant; and
Tenn. Comp. R. & Regs. 0400-40-14-.07
Authority: T.C.A. §§ 4-5-201, et seq., and 69-3-101, et seq.