Section 096-528-18 - Modification of POTW Pretreatment Programs [see 40 CFR 403.18](a) General. Either the Approval Authority or a POTW with an approved POTW Pretreatment Program may initiate program modification at any time to reflect changing conditions at the POTW. Program modification is necessary whenever there is a significant change in the operation of a POTW Pretreatment Program that differs from the information in the POTW's Submission, as approved under Section 11. (b) Procedures. POTW Pretreatment Program modifications shall be accomplished as follows: (1) For substantial modifications, as defined in paragraph (c) of this section: (i) The POTW shall submit to the Approval Authority a statement of the basis for the desired modification, a modified program description (see, Section 10(b)), or such other documents the Approval Authority determines to be necessary under the circumstances.(ii) The Approval Authority shall approve or disapprove the modification based on the requirements of Section 9(f), following the procedures in Section 11(b)-(f).(iii) The modification shall be incorporated into the POTW's MEPDES permit after approval.(iv) The modification shall become effective upon approval by the Approval Authority. Notice of approval shall be published in the same newspaper as the notice of the original request for approval of the modification under Section 11(b)(1)(i)(B).(2) The POTW shall notify the Approval Authority of any other (i.e., non-substantial) modifications to its Pretreatment Program at least 30 days prior to when they are to be implemented by the POTW, in a statement similar to that provided for in paragraph (b)(1)(i) of this section. Such non-substantial program modifications shall be deemed to be approved by the Approval Authority, unless the Approval Authority determines that a modification submitted is in fact a substantial modification, 90 days after the submission of the POTW's statement. Following such ``approval'' by the Approval Authority, such modifications shall be incorporated into the POTW's permit. If the Approval Authority determines that a modification reported by a POTW in its statement is in fact a substantial modification, the Approval Authority shall notify the POTW and initiate the procedures in paragraph (b)(1) of this section.(c) Substantial modifications. (1) The following are substantial modifications for purposes of this section: (i) Changes to the POTW's legal authorities;(ii) Changes to local limits, which result in less stringent local limits;(iii) Changes to the POTW's control mechanism, as described in Section 9(f)(1)(iii);(iv) Changes to the POTW's method for implementing categorical Pretreatment Standards (e.g., incorporation by reference, separate promulgation, etc.);(v) A decrease in the frequency of self-monitoring or reporting required of industrial users;(vi) A decrease in the frequency of industrial user inspections or sampling by the POTW;(vii) Changes to the POTW's confidentiality procedures;(viii) Significant reductions in the POTW's Pretreatment Program resources (including personnel commitments, equipment, and funding levels); and(ix) Changes in the POTW's sludge disposal and management practices.(2) The Approval Authority may designate other specific modifications, in addition to those listed in paragraph (c)(1) of this section, as substantial modifications.(3) A modification that is not included in paragraph (c)(1) of this section is nonetheless a substantial modification for purposes of this section if the modification: (i) Would have a significant impact on the operation of the POTW's Pretreatment Program;(ii) Would result in an increase in pollutant loadings at the POTW; or(iii) Would result in less stringent requirements being imposed on Industrial Users of the POTW.06-096 C.M.R. ch. 528, § 18