Wastewater treatment system
Wastewater treatment system means any component, piece of equipment, or installation that receives, manages, or treats process wastewater, product tank drawdown, or landfill leachate prior to direct or indirect discharge in accordance with the National Pollutant Discharge Elimination System permit regulations under 40 CFR part 122. These systems typically include individual drain systems, oil-water separators, air flotation units, equalization tanks, and biological treatment units.
40 CFR § 61.341
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.