The National Pollutant Discharge Elimination System (NPDES) was established to regulate the discharge of pollutants to waters of the United States. The U.S. Environmental Protection Agency (EPA) administers the NPDES program but delegates this authority to the Arkansas Department of Environmental Quality (ADEQ) within the State. Since construction sites produce sediment and other pollutants which could be transported off-site during rain events, ADEQ issues a NPDES General Construction Permit that is applicable to construction projects.
The NPDES General Construction Permit requires all construction sites that disturb one acre or more of soil to obtain general permit coverage and to develop, implement, and maintain a Stormwater Pollution Prevention Plan (SWPPP) designed to minimize the discharge of pollutants while construction is in progress.
The ARDOT has well established procedures to implement the requirements of the construction stormwater program. In most cases, the process begins with the project designer who develops the SWPPP as part of the overall design. The designers use information from many sources to ensure the plan is effective in preventing the discharge of sediment while the project is underway. Typically, the SWPPPs are reviewed at several levels to ensure they will be effective.
After the project design and SWPPP are complete, the ARDOT submits a Notice of Intent to ADEQ to obtain NPDES coverage for projects of five acres or more, with small jobs proceeding under the automatic coverage provision of the construction permit
The majority of construction projects undertaken by the ARDOT are then let to independent contractors who install and maintain BMPs and implement construction waste control in accordance with the SWPPP. Once the job is contracted, it is normally under the oversight of a Resident Engineer with on-site inspectors to ensure the contractor complies with the SWPPP requirements for installation and maintenance of BMPs and the control of construction waste. The ARDOT inspectors complete a formal inspection of each permitted project every seven days, document the results on an inspection form and, after approval by the Resident Engineer, provide a copy to the contractor to use in correcting deficiencies.
If the district personnel find the SWPPP is not working as designed, they have the authority and responsibility to initiate changes to correct any deficiencies.