Section 327IAC5-5-2. Technology-based treatment requirements

   (a) Technology-based treatment requirements under sections 301(b) and 306 of the CWA represent the minimum level of control that must be imposed in an NPDES permit issued under section 402 of the CWA for an existing source and a new source, respectively. Compliance with these technology-based treatment requirements is required within the times prescribed in section 301(b)(2) of the CWA and 40 CFR 123.3(a)(2). Notwithstanding these minimum technology-based requirements, more stringent treatment requirements may be imposed under section 301(b)(1)(C), 302, or 307(a)(2) of the CWA.

  (b) Technology-based treatment requirements may be imposed through one (1) of the following methods:

(1) Application of EPA-promulgated effluent limitations developed under section 304 or 306 of the CWA to discharges by category or subcategory. These effluent limitations are not applicable to the extent that they have been remanded or withdrawn. However, in the case of a court remand, determinations underlying effluent limitations shall be binding in permit issuance proceedings where those determinations are not required to be reexamined by a court remanding the regulations. In addition, dischargers may seek fundamentally different factors variances from these effluent limitations under 327 IAC 5-6. If a fundamentally different factors variance is approved by EPA under 40 CFR 125, Subpart D, the resulting effluent limitations are technology-based treatment requirements for purposes of this article.

(2) On a case-by-case basis under section 402(a)(1) of the CWA, to the extent that EPA-promulgated effluent limitations are unavailable. Standards of performance for new sources cannot be developed on an ad hoc basis under section 402(a)(1) of the CWA. By statutory definition, a source is a new source only if standards of performance applicable to such source have been promulgated by EPA. The commissioner shall apply the appropriate factors listed in section 304 of the CWA and shall consider the following:

(A) The appropriate technology for the category or class of point sources of which the applicant is a member, based upon all available information (including EPA draft or proposed development documents or guidance).

(B) Any unique factors relating to the applicant.

(3) Through a combination of the methods in subdivisions (1) and (2). Where promulgated effluent limitations guidelines only apply to certain aspects of the discharger's operation, or to certain pollutants, other aspects or activities are subject to regulation on a case-by-case basis in order to carry out the provisions of the CWA.

  (c) Technology-based treatment requirements are applied prior to or at the point of discharge.

  (d) Technology-based treatment requirements cannot be satisfied through the use of nontreatment techniques such as flow augmentation and instream mechanical aerators. However, these techniques may be considered as a method of achieving water quality standards on a case-by-case basis when:

(1) the technology-based treatment requirements applicable to the discharge are not sufficient to achieve the promulgated water quality standards;

(2) the discharger agrees to waive any opportunity to request a variance under section 301(c) or 301(g) of the CWA; and

(3) the discharger demonstrates that such a technique is the preferred environmental and economic method to achieve the standards after consideration of alternatives such as advanced waste treatment, recycle and reuse, land disposal, changes in operating methods, and other available methods.

  (e) Technology-based effluent limitations shall be established under this rule for solids, sludges, filter backwash, and other pollutants removed in the course of treatment or control of wastewaters in the same manner as for other pollutants if such pollutants are proposed to be discharged.

  (f) Other provisions of this rule notwithstanding, the commissioner may do the following:

(1) Set a permit limit for conventional pollutants at a level more stringent than the best conventional pollution control technology (BCT), or a limit for a nonconventional pollutant which shall not be subject to modification under section 301(c) or 301(g) of the CWA, where:

(A) effluent limitations guidelines specify the pollutant as an indicator for a toxic pollutant; or

(B)(i) the limitation reflects BAT level control of discharges of one (1) or more toxic pollutants which are present in the waste stream, and a specific BAT limitation upon the toxic pollutants is not feasible for economic or technical reasons;

(ii) the permit identifies which toxic pollutants are intended to be controlled by use of the limitation; and

(iii) the fact sheet required by 327 IAC 5-3-8 sets forth the basis for the limitation, including a finding that compliance with the limitation will result in BAT level control of the toxic pollutant discharges identified in item (ii), and a finding that it would be economically or technically infeasible to directly limit the toxic pollutants.

(2) Set a permit limit for a conventional pollutant at a level more stringent that [sic., than] BCT when any of the following occur:

(A) Effluent limitations guidelines specify the pollutant as an indicator for a hazardous substance.

(B) The following are established:

(i) The limitation reflects BAT level control of discharges (or an appropriate level determined under section 301(c) or 301(g) of the CWA) of one (1) or more hazardous substances which are present in the waste stream, and a specific BAT (or other appropriate) limitation upon the hazardous substances is not feasible for economic or technical reasons.

(ii) The permit identifies which hazardous substances are intended to be controlled by use of the limitation.

(iii) The fact sheet sets forth the basis for the limitation, including a finding that compliance with the limitations will result in BAT level (or appropriate level) control of the hazardous substances discharges identified in item (ii), and a finding that it would be economically or technically infeasible to directly limit the hazardous substances.

(C) Hazardous substances which are also toxic pollutants are subject to subdivision (1).

(3) Not set a more stringent limit under subdivision (1) or (2) if the method of treatment required to comply with the limit differs from that which would be required if the toxic pollutants or hazardous substances controlled by the limit were limited directly.

  (g) Toxic pollutants identified under subsection (f)(1) remain subject to the requirements of 327 IAC 5-2-9, concerning notification of increased discharges of toxic pollutants above levels reported in the application form.

  (h) In setting case-by-case limitations pursuant to subsection (b), the permit writer must consider the following factors:

(1) The following are requirements for BPT:

(A) The total cost of application of technology in relation to the effluent reduction benefits to be achieved from such application.

(B) The age of equipment and facilities involved.

(C) The process employed.

(D) The engineering aspects of the application of various types of control techniques.

(E) Process changes.

(F) Nonwater quality environmental impact, including energy requirements.

(2) The following are requirements for BCT:

(A) The reasonableness of the relationship between the costs of attaining a reduction in effluent and the effluent reduction benefits derived.

(B) The comparison of the cost and level of reduction of such pollutants from the discharge from publicly owned treatment works to the cost and level of reduction of such pollutants from a class or category of industrial sources.

(C) The age of equipment and facilities involved.

(D) The process employed.

(E) The engineering aspects of the application of various types of control techniques.

(F) Process changes.

(G) Nonwater quality environmental impact, including energy requirements.

(3) The following are requirements for BAT:

(A) The age of equipment and facilities involved.

(B) The process employed.

(C) The engineering aspects of the application of various types of control techniques.

(D) Process changes.

(E) The cost of achieving such effluent reduction.

(F) Nonwater quality environmental impact, including energy requirements.

(Water Pollution Control Division; 327 IAC 5-5-2; filed Sep 24, 1987, 3:00 p.m.: 11 IR 645; filed Feb 26, 1993, 5:00 p.m.: 16 IR 1765; readopted filed Jan 10, 2001, 3:23 p.m.: 24 IR 1518; readopted filed Nov 21, 2007, 1:16 p.m.: 20071219-IR-327070553BFA; readopted filed Jul 29, 2013, 9:21 a.m.: 20130828-IR-327130176BFA)