Office of Air Quality, Permitting & Enforcement Division Mechanical Section Policy Memorandum þÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ Date: February 23, 1994 No.: 11 From: Skip Clark, P.E. Approved by: Gary Wallin, P.E. Subject: Standard Exemption No. 73 þÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍÍ Policy: The production rate of 200 tons per hour for a rock crusher under Standard Exemption No. 73 means the total production or output from the entire facility. Background: If a facility screens the material before it goes to the primary crusher in order to bypass a portion of the feed, the total production should include both the primary crusher material and the bypassed material. The company may want to bypass the fines, or small material, from the primary crusher in order to maximize the output of the crusher and not waste crushing capacity on material that is already sized. The intent of this exemption was to limit total production to 200 tons per hour. Also, the rated capacity of the crusher is the determining factor on its size. A crusher with a rated capacity greater than 200 tons per hour is not allowed even if the company welds, or attaches, some type of devices on the feed end to limit the input to the crusher. Also, if the facility has a secondary, or tertiary, crusher to process the output from the primary crusher, they are allowed since the total production from the facility will not be greater than 200 tons per hour. Necessary Action: Clarify the wording in the first sentence of this exemption to reflect the original intent of this exemption. cc: All Mechanical Section