1. a) Request for an FDF determination and supporting information must be submitted in writing to the Agency.

2. b) To be considered, requests for FDF determinations must be submitted within the following time limits:

   1. 1) Prior to authorization of the Illinois program, FDF requests must be directed to USEPA pursuant to 40 CFR 403.13.
   2. 2) For standards adopted by USEPA after authorization of the Illinois pretreatment program, the industrial user must request an FDF determination within 180 days after the Board adopts or incorporates the standard by reference unless the user has requested a category determination pursuant to Section 310.221.

3. c) Where the industrial user has requested a category determination pursuant to Section 310.221, the user may elect to await the results of the category determination before submitting a request for an FDF determination. Where the user so elects, the user must submit the request within 30 days after a final decision has been made on the categorical determination pursuant to Section 310.221(d).

   BOARD NOTE: Derived from 40 CFR 403.13(g) (2005), as amended at 70 Fed. Reg. 60134 (Oct. 14, 2005).

(Source: Amended at 47 Ill. Reg. 5083, effective March 23, 2023)