February 12, 2004


Dave Reynolds
Leisch Associates, Inc.
13400 15th Avenue North
Minneapolis, Minnesota 55441

Dear Mr. Reynolds:

This is in response to your letter regarding Marshfield DoorSystems, Inc. (MDSI) in Marshfield, Wisconsin, which we received on December 10, 2003. You have requested a prevention of significant deterioration (PSD) applicability determination for potential modifications at MDSI's Steam-Thru process. MDSI modified this facility several years ago at which time MDSI accepted throughput limits to stay below the 40 ton per year PSD significance threshold for nitrogen oxides. According to your letter, MDSI is an existing major source but is seeking to be re-permitted as a synthetic minor through source-wide emission caps. In addition, you stated that, based on Wisconsin Department of Natural Resources (WDNR) emissions inventory records, MDSI's actual emissions have not exceeded the 250 ton per year PSD major source threshold at least since 1991.

In Wisconsin, the WDNR has the authority to issue PSD permits and make PSD applicability determinations. This authority was approved by the United States Environmental Protection Agency (EPA) on May 27, 1999, and became effective on June 28, 1999 (See Federal Register notice 64 FR 28745). Pursuant to this approval, WDNR issues PSD applicability determinations for Wisconsin and sources should contact WDNR for permit determinations. It is our understanding that you have contacted WDNR regarding this issue and are seeking EPA's position on this matter. The following is our position, based on Federal regulations, on the appropriate application of the PSD requirements, but WDNR will make the final permit determination based on Wisconsin's regulations.

In your letter, you state the position that the provision in 40 CFR 52.21(r)(4) will not be applicable to MDSI due to the source's reclassification from a major to a synthetic minor source. However, it is our position that a source's synthetic minor status cannot be applied retroactively. Even if past actual emissions were below the PSD threshold, the source has had potential emissions above major source levels. The source will continue to be considered a major source until is obtains the appropriate source-wide emission limits. Since MDSI obtained the synthetic minor limit on the Steam-Thru process when the source was considered a major stationary source, we believe that the provisions of 40 CFR 52.21(r)(4) will apply to changes made to that synthetic minor limit. Therefore, any modifications that would affect the sander-dust throughput limit, or any other limit previously taken to avoid major PSD requirements, would have to be reviewed pursuant to the provision in 40 CFR 52.21(r)(4) in order to determine major source applicability.

If you have any questions, contact Sam Portanova, of my staff, at (312) 886-3189.



Pamela Blakley, Chief
Air Permits Section

File Attachment Icon