15. (1) Beginning on January 1, 1996, each discharger may annually calculate a revised daily plant loading limit and a revised monthly average plant loading limit for each limited parameter.  O. Reg. 760/93, s. 15 (1). (1.1) Beginning on January 31, 1997, each discharger for the Thunder Bay Packaging Inc. plant may annually calculate a revised daily plant loading limit and a revised monthly average plant loading limit for each limited parameter.  O. Reg. 521/95, s. 9. (1.2) Subsection (1) does not apply to a discharger referred to in subsection (1.1).  O. Reg. 521/95, s. 9. (2) Despite subsection (1), beginning on January 1, 1995, each discharger for which a limit for AOX is listed in Columns 3 and 4 of the Table for the discharger’s plant in Schedule 2 may annually calculate a revised daily plant loading limit and a revised monthly average plant loading limit for AOX.  O. Reg. 760/93, s. 15 (2); O. Reg. 300/17, s. 3 (1). (3) Each discharger shall calculate, to three significant figures, a revised daily plant loading limit for a limited parameter by dividing the revised reference production rate of finished product at the discharger’s plant as determined under subsection (4) by the reference production rate of finished product specified in Schedule 4 for the discharger’s plant, and multiplying that ratio by the daily plant loading limit specified for the parameter and the plant in Column 3 of the Table for the plant in Schedule 2.  O. Reg. 760/93, s. 15 (3); O. Reg. 300/17, s. 3 (2). (4) For the purposes of subsection (3), the revised reference production rate of finished product at a discharger’s plant is equal to the highest value of the ninetieth percentiles of the daily production of finished product at the plant for the three calendar years preceding the calendar year in which the revised limit is to come into force.  O. Reg. 760/93, s. 15 (4). (5) To determine the highest value of the ninetieth percentiles of the daily production of finished product at the plant for the three calendar years, the discharger shall do the following: 1.  Determine, in tonnes, the amount of dried finished product that was produced by the plant on each day that the plant operated in each of the three calendar years. 2.  For each of the three calendar years, determine the statistically derived value that is equal to the amount of dried finished product, produced daily by the plant, that was exceeded on 10 per cent of the days that the plant operated in that calendar year. 3.  Take the highest of the values determined under step 2.  O. Reg. 760/93, s. 15 (5). (6) The reference production rate and the revised reference production rate to be used for the purpose of calculating a revised daily plant loading limit for AOX are the rates of production of bleached pulp and, for the purpose, a reference in subsections (3) to (5) to finished product shall be deemed to be a reference to bleached pulp.  O. Reg. 760/93, s. 15 (6). (7) Revoked: O. Reg. 300/17, s. 3 (3). (8) If the revised daily plant loading limit calculated for a limited parameter under subsection (3) exceeds the daily plant loading limit specified for the parameter and the plant in Column 3 of the Table for the plant in Schedule 2 by no more than 15 per cent, the discharger may notify the Director in writing of the value of the revised limit and of the value of the revised reference production rate used for the purpose of calculating that limit.  O. Reg. 760/93, s. 15 (8); O. Reg. 300/17, s. 3 (4). (9) A notice under subsection (8) shall be given to the Director in writing on or before January 31 in the calendar year in which the revised limit is to come into force.  O. Reg. 760/93, s. 15 (9). (10) Where a notice is given under subsection (8), the revised daily plant loading limit calculated for the limited parameter under subsection (3) shall be deemed to replace the daily plant loading limit specified for the parameter and the plant in Column 3 of the Table for the plant in Schedule 2.  O. Reg. 760/93, s. 15 (10); O. Reg. 300/17, s. 3 (4). (11) Despite subsection (10), the daily plant loading limit specified for a parameter and a plant in Column 3 of the Table for the plant in Schedule 2 shall always be used for the purpose of making a calculation under subsection (3) or for the purpose of making a determination under subsection (8) or (14).  O. Reg. 760/93, s. 15 (11); O. Reg. 300/17, s. 3 (4). (12) Where a notice is given under subsection (8) with respect to a limited parameter and a revised daily plant loading limit is already in force with respect to the limited parameter, the revised daily plant loading limit calculated for the limited parameter under subsection (3) shall be deemed to replace the revised daily plant loading limit that is currently in force.  O. Reg. 760/93, s. 15 (12). (13) Subsections (3) to (12) apply with necessary modifications for the purpose of calculating and using a revised monthly average plant loading limit and, for the purpose, a reference in those subsections to a revised daily plant loading limit shall be deemed to be a reference to a revised monthly average plant loading limit, a reference to a daily plant loading limit shall be deemed to be a reference to a monthly average plant loading limit, and a reference to Column 3 of the Table for the plant in Schedule 2 shall be deemed to be a reference to Column 4 of the Table for the plant in Schedule 2.  O. Reg. 760/93, s. 15 (13); O. Reg. 300/17, s. 3 (4). (14) If a revised limit calculated for a limited parameter under subsection (3) exceeds the applicable limit specified for the parameter and the plant in Column 3 or 4 of the Table for the plant in Schedule 2 by more than 15 per cent, the discharger may apply to the Director for approval to revise the limit.  O. Reg. 760/93, s. 15 (14); O. Reg. 300/17, s. 3 (4). (15) An application under subsection (14) shall be submitted together with the results of a receiving water assessment study that the discharger has prepared for the purpose of identifying what effect the proposed revised limit would have on the receiving water.  O. Reg. 760/93, s. 15 (15). (16) The Director shall approve an application under subsection (14) if the Director is satisfied, based on the results of the receiving water assessment study, that the proposed revised limit would not have an adverse effect on the receiving water.  O. Reg. 760/93, s. 15 (16). (17) Revoked: O. Reg. 300/17, s. 3 (5). (18) Nothing in this section shall be interpreted to relieve a discharger of the obligation to apply for any environmental compliance approval that may be required under the Ontario Water Resources Act or the Environmental Protection Act.  O. Reg. 760/93, s. 15 (18); O. Reg. 259/11, s. 1. Lethality Limits