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Regulatory Information

Stop 11: Wastewater Treatment

Highlighted Topic:  Wastewater Discharge and Stormwater Issues

Tour Stop 11Wastewater generated at a chemical plant will likely be treated on-site and then discharged either to a sewer authority or directly to a waterway.

Sewer discharge:

Chemical plant wastewaters that are delivered to a sewer authority or Publicly Owned Treatment Works (POTW) are covered by the Clean Water Act's   "pretreatment" regulations. There are two types of pretreatment requirements: 1) categorical standards developed by the EPA that apply to each industry, and 2) local standards developed by each POTW. Under the pretreatment program, you will have to register with the EPA and your POTW, and meet certain permit limits as well as performing  monitoring and reporting.

Note that all wastewater discharges to a POTW need to be considered here, including not only process line discharges, but also discharges from other activities, such as throwing chemicals or cleaning materials down the drain during laboratory work or maintenance activities.

Direct discharge:

Whenever there is wastewater discharging from a pipe or other "point" source into a waterway (river, lake, even intermittent stream), you will be subject to the Clean Water Act’s National Pollution Discharge Elimination System (NPDES) permit program.  Common NPDES wastewater sources include process operations and cooling towers.

Your NPDES permit will limit the types and amounts of pollutants that can be directly released into waterways.  Under NPDES, you need to register with appropriate authorities, procure a permit, and do regular monitoring and reporting of your wastewater discharges. The NPDES permit is issued either by EPA or by your state agency, depending on whether the state has gained authority for the program from EPA.

Storm water:

It has been widely recognized that stormwater runoff from industrial sites can often contain high levels of harmful contaminants - including both process chemicals and materials from vehicles, hard machinery, and other sources. To protect waterways, facilities must now get a National Pollution Discharge Elimination System (NPDES) permit for their stormwater drains.

This NPDES permit works much like the permit you would get for other wastewater discharges.  Again, the permit will be issued either by EPA or your state agency depending on whether the state has gained authority for the program from EPA.

Other Regulatory Issues:

Your on site wastewater treatment facility as well as your final water discharge might cause air emissions. If so, these sources will need to be counted as part of your overall air source and managed for fugitive emissions.