Water quality in the United States is regulated by the Federal Water Pollution Act, as amended by the Clean Water Act (CWA) of 1977 and further amendments in 1987. It has the objective of restoring and maintaining the chemical, physical, and biological integrity of the nation's navigable waters. This legislation gave authority to the Environmental Protection Agency (EPA) to establish regulatory standards for wastewater discharges, stormwater runoff, and sewage sludge use and disposal practices. The primary tool for wastewater compliance is through the National Pollutant Discharge Elimination System (NPDES) program, generally delegated to and overseen by state environmental programs. NPDES permits are issued and monitored to private and federal facilities ensure compliance with the standards.Sill maintains several different permits related to onsite stormwater activity:
- OKR04 ODEQ Water Quality Divisions General Permit
- OKR05 Phase I ODEQ Multi-Sector Industrial General Permit
- OKR10 OPDES General Permit for Stormwater Discharges From Construction Activities Within the State of Oklahoma
Polluted stormwater runoff from construction sites on Fort Sill has the potential to flow into local rivers and streams that can carry pollutants off the installation. The EPA recognizes the following list of pollutants as those commonly discharged from construction sites: sediment, solid and sanitary wastes, phosphorus, nitrogen, pesticides, oil and grease, concrete truck washout, construction chemicals, and construction debris. Of these pollutants, sediment is usually the main pollutant of concern. Increased sedimentation and the contribution of other pollutants from construction sites has the potential to cause physical, chemical, and biological harm to the waters of the State.
The Oklahoma Pollution Discharge Elimination System (OPDES) stormwater program, authorized by the NPDES stormwater permitting program, requires construction site owners/operators to obtain coverage under the OPDES Construction General Permit OKR10 to discharge stormwater from their construction sites and implement appropriate pollution prevention controls/techniques to minimize pollutants and reduce stormwater runoff.
Industrial facilities typically perform a portion of their activities such as material storage and handling, vehicle fueling and maintenance, shipping and receiving materials in outdoor areas exposed to the weather. Stormwater runoff from these activities picks up industrial pollutants and discharges them directly into nearby waterbodies or indirectly via storm sewer systems. In addition, accidental spills and leaks, improper waste disposal, and illicit connections to storm sewers may also lead to exposure of pollutants to stormwater. This increased pollutants load in the stormwater runoff can impair waterbodies, degrade biological habitats, pollute drinking water sources.
As part of the application process, the owner or operator must develop a stormwater pollution prevention plan (SWPPP) that explains how it will control & reduce pollutants in the stormwater runoff and submit a notice of intent (NOI) or permit application to DEQ.
Stormwater runoff from an urbanized area is commonly transported through Municipal Separate Storm Sewer Systems (MS4s). Urbanized areas are associated with different activities that contribute pollutants to stormwater runoff. Additionally, urbanized areas are characterized by large amounts of impervious surfaces such as streets, sidewalks, driveways, parking lots, and roof tops. Stormwater runoff from impervious surfaces travels faster which results in damage to the waterbodies and causes flooding and hydrologic changes to the receiving waters. Elevated pollutant levels can impair waterbodies, degrade biological habitats, and pollute drinking water sources.
Fort Sill is designated as a Category 1 small MS4 by the OKR04. These small MS4s serve a population of less than 10,000 within an UA, (ODEQ, 2020).