Section 309.157  Permit Limits for Total Metals

a)         The NPDES permit limits for metals must be expressed in total metals form even though the water quality standards for metals specified in Sections 302.208(e), 302.504(a), and 304.105 are in their dissolved form.  The total metals permit limit shall be determined by multiplying the dissolved metals concentration and the appropriate metals translator.

b)         The Agency shall adopt procedures for determining site-specific metals translator in accordance with "The Metals Translator: Guidance for Calculating a Total Recoverable Permit Limit from a Dissolved Criterion," incorporated by reference at 35 Ill. Adm. Code 301.106.

c)         Except as otherwise specified in subsection (d) of this Section,  the reciprocal of the conversion factor multiplier used for obtaining the dissolved metals standards at Sections 302.208(e) and 302.504(a) becomes the metals translator and the resulting total metals value becomes the NPDES permit limit.

d)           A permittee may request the Agency, in accordance with the procedures adopted pursuant to subsection (b) of this Section, to calculate a total metals permit limit based on a site-specific metals translator.  Upon review and approval of the information submitted by the permittee, the Agency will calculate a total metals permit limit that is protective of the dissolved metals water quality standard.

(Source:  Added at 27 Ill. Reg. 202, effective December 20, 2002)