Water seal controls

Water seal controls means a seal pot, p-leg trap, or other type of trap filled with water (e.g., flooded sewers that maintain water levels adequate to prevent air flow through the system) that creates a water barrier between the sewer line and the atmosphere. The water level of the seal must be maintained in the vertical leg of a drain in order to be considered a water seal.

Source

40 CFR § 61.341

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Scoping language

Benzene concentration means the fraction by weight of benzene in a waste as determined in accordance with the procedures specified in 61.355 of this subpart.

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