Main Menu

IDEM Proposes Guidelines for Approval and Use of Representative Stack Test Data


By Jennifer Thompson, Attorney, Bingham Greenebaum Doll LLP

The Indiana Department of Environmental Management (“IDEM”) has proposed a new non-rule policy entitled “Guidelines for Approval and Use of Representative Stack Test Data”, Air-034-NPD (“NPD”). The proposed NPD sets forth the criteria IDEM will utilize when determining whether representative test data may be used to provide emission factors for permitting decisions, emission estimations for billing purposes, or to demonstrate compliance in lieu of a stack test. “Representative test data” means test data submitted in lieu of actual testing of a particular emission unit. Examples of representative test data include testing conducted by a trade group on units that are identical or very similar to the subject unit, testing of identical units at another site owned by the same company, mass balance studies, and testing using equivalent test methods approved by U.S. EPA.

The policy applies to units having potential emissions less than one hundred (100) tons per year of any regulated pollutant and with actual emissions less than fifty percent (50%) of an applicable limit. Pursuant to the policy, said sources may petition to use representative test data obtained from identical or very similar processes utilizing U.S. EPA approved or equivalent methods found in the appendices of 40 CFR Parts 51 and 60, Conditional Test Methods published by U.S. EPA or other sampling methods such as those published by the American Society for Testing and Materials (“ASTM”), the California Air Resources Board (“CARB”) or the National Council for Air and Stream Improvement (“NCASI”).

Requests and/or permit applications seeking IDEM’s approval to utilize representative stack test data should include the following information:

  1. A description of the process and any associated air pollution control equipment.
  2. A description of how the process for which the request is being made is identical (or at least very similar in design, operation, and control) to the process previously tested, including the identification of the process or equipment manufacturer, model number or other manufacturer’s designation, rated capacity, operating specifications and control device specifications.
  3. Complete test results and a description of the sampling methodology used while performing the test, including sample calculations and all required quality assurance requirements.
  4. Process data to document how the unit was run during the test, including process operating speed, raw materials used or type of fuel combusted.
  5. Air pollution control monitoring data to document how the air pollution control unit was operated during the test, including flow rates, pressure drops, temperatures and other monitoring associated with the control device as applicable.

After receiving comments from the public through August 24, 2009 on the proposed NPD, IDEM will present the NPD to the Air Pollution Control Board (“APCB”). IDEM has tentatively scheduled its presentation for the November 4, 2009 APCB meeting. IDEM may put the NPD into effect thirty (30) days after it has been presented to the APCB.


Back to Page