FAX TRANSMISSION

Headquarters, US EPA

401 M St., S.W.

Washington, D.C. 20460

Date: October 18, 1995

To: Jim Claffey, Brown & Caldwell

Fr: Mark Ingle, Project Officer, Metal Products and Machinery, Phase II

Re: Definitions Related to Implementation of 40 CFR 433, Metal Finishing

Introduction

On October 18, 1995, you called requesting information regarding the following:

1. Definition of a plant used to apply the 40 CFR 433 effluent limitation guideline to industrial facilities.

2. Method by which more than one effluent limitation guideline would be applied to a single industrial plant.

The following discussion and attachments provide the information you requested.

Discussion

The 40 CFR 433 effluent limitation guideline does not include a specific definition of a "plant." As such, local permit writers can use their best professional judgement in defining a plant for purposes of regulation. In general, plants are considered to be "fence-line to fence-line" facilities owned by a single company. Plants may be extremely large and may even be bisected by roads that are "owned" by various other entities. In fact, some non-contiguous facilities may still be considered one plant for the purpose of permitting if wastewater effluents are combined at a single pretreatment system (i.e., wastewater is trucked or piped from the non-contiguous facilities to a central pretreatment system located at one of the plants). Plants may also have more than one, or more than one type of, wastewater outfall. For example, single plants may have a direct discharge to a surface water body and an indirect discharge to a publicly owned treatment works. However, individual plants have individual NPDES permit numbers (i.e., one NPDES number may cover more than one discharge point).

Attachment A includes the 40 CFR 403 pages describing the combined wastestream formula and a reference to an implementation document describing the formulas actual use in permitting. As shown in Attachment A, the combined wastestream formula is designed to allow effluents regulated under two or more separate effluent limitations guidelines subcategories to be combined in a single plant permit

If you have any questions, or need additional information, please feel free to call me at (202) 260-7191.