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The applicability conditions of the Benzene Waste Operations NESHAP (BWON), codified in 40 CFR 61 Subpart FF, state that the BWON provisions apply to owners and operators of chemical manufacturing plants, coke-by-product recovery plants, and petroleum refineries. Since the definition of a chemical manufacturing plant can vary depending on the regulation being reviewed, this article aims to clarify what type of facilities are subject to the BWON regulation.

A chemical manufacturing plant is defined in the BWON as any facility engaged in the production of chemicals by chemical, thermal, physical, or biological processes for use as a product, a co-product, by product, or intermediate… While the rule includes examples of facilities that manufacture specific chemicals, it is important to note that the list of chemicals is not exhaustive. Similarly, the preamble to the BWON and subsequent amendments listed certain industrial categories that are regulated under the BWON, noting that the list is not comprehensive of regulated entities and is provided only as a guide regarding entities likely to be regulated.

So, what other types of facilities might be subject to the BWON, if they weren't included in the examples provided in the rule and the preamble?

The 1996 Benzene NESHAP FAQ for Subpart FF provided some clarification, explaining there is no exclusion for chemical mixing and blending facilities, since benzene-containing waste streams may be created. Furthermore, if benzene occurs in material at any stage of production, benzene has the potential to arrive in waste streams; consequently, the BWON applies to chemical manufacturing plants where benzene occurs in one or all the following: raw materials, intermediates, or the final product. However, analogous to miscellaneous organic chemical (MON) manufacturing industry interpretations, the intent of the BWON is to cover the production of chemicals, not to cover end-users of those chemicals in the manufacture of goods.

Additionally, facilities identified as a “chemical process plant,” one of the 28 source categories named in the New Source Review (NSR) definition of a major stationary source, would be considered a chemical manufacturing plant and subject to the BWON. Another important consideration is that if a facility is subject to one of the MACT standards containing overlap provisions with the BWON, it is presumed that the facility falls in a source category that is subject to the BWON. Moreover, if any one process at a facility triggers the provisions of the BWON, the entire facility is subject to the regulation. If a facility is engaged in several activities, the BWON applies even to those activities that would not have themselves triggered the BWON.

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