July 29, 1997

John A. Gibson, Safety Manager
Roto-Die Company, Inc.
800 Howerton Lane
Eureka, Missouri 63025

Re: Chromium Strip Tank Applicability to 40 CFR Part 63, Subpart N, Chromium Electroplating and Anodizing NESHAP

Dear Mr. Gibson:

The U.S. Environmental Protection Agency (EPA) has reviewed the letter from Roto-Die Company, Inc. (Roto-Die) dated May 13, 1997 regarding classification of two chrome strip tanks under 40 CFR Part 63, Subpart N, Chromium Electroplating and Anodizing NESHAP. The strip tanks referred to in the letter are operated at Preston Engravers, Inc. of East Windsor, Connecticut. This letter provides Roto-Die with a written applicability determination.

Forty CFR Part 63, Section 63.340(a) identifies an affected source as each chromium electroplating or anodizing tank at facilities performing hard chromium electroplating, decorative chromium electroplating, or chromium anodizing. Section 63.340(c) specifies that process tanks associated with a chromium electroplating or chromium anodizing process, but in which neither chromium electroplating nor chromium anodizing is taking place, are not subject to the provisions of Subpart N. Chromium anodizing and chromium electroplating involve the deposition of a chromium or oxide layer to a base material. Therefore, a chrome strip tank which removes the layer of chromium is not subject to the standard. Although strip tanks are not regulated under Subpart N, EPA is pleased with the companys decision to control the emissions from the strip tanks by connecting the tanks to air pollution control equipment.

This applicability determination does not relieve Preston Engravers, Inc. of responsibility for complying fully with any and all applicable federal, state and local laws, regulations and permits.

If you have any questions about this determination or need further assistance, please contact Susan Lancey of my staff at (617) 565-3587.

Sincerely yours,

John P. DeVillars
Regional Administrator

cc: Scott Throwe, EPA HQ; Ellen Morris, CT DEP