The 82nd State General Assembly passed
legislation,*pdf which required the Department to write new rules and a provide issuance of a General Permit to authorize well construction and well services related wastewater discharge when that discharge reaches a Water of the United States.
Starting on March 17, 2010, all well construction or well service related wastewater that reaches a Water of the United States is regulated by a new National Pollution Discharge Elimination System permit (NPDES) designated
General Permit #6,*pdf or GP6.
Anytime the discharge wastewater generated by well related construction and services reaches a Water of the United States, the wastewater falls under the requirements stated in GP6 and must adhere to the terms and conditions contained within the general permit. If the well construction or well services related wastewater does not reach Waters of the United States, it is not subject to GP6.
Why is well construction and well service related wastewater regulated?
Many well sites are located in close proximity to waterways or other conveyances and allow the wastewater to reach a waterway or other conveyance that flows into a Water of the United States. This wastewater normally consists of drilling fluids and/or groundwater, and contains particles of natural materials like sand, silt, colloids (clays), limestone and dolomite, and various chemical additives. When allowed to flow untreated, wastewater will eventually reach a stream, river or a lake where it slows down, allowing the particles to settle out of suspension. This results in turbidity that can affect aquatic life and sedimentation that can create long term changes to the waterway.
In addition, drilling fluid additives and other products used in borehole construction and well servicing may contain substances that are acutely toxic when released in a stream or river. These products can chemically and physically alter the receiving water and cause additional problems, such as killing aquatic life present in the water and inhibiting the life processes for all species that depend on the water as part of their daily needs. In addition, untreated well related wastewater inhibits the use and enjoyment of the adjoining property owners and citizens who access the water.
Well construction discharge at the point of stream entry. |
Well construction discharge after mixing - downstream 200 feet. |
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What well services are included in the GP6?
- All types of new water supply well construction including:
- Private and public water drinking water supply wells
- Non-potable use wells such as irrigation wells, plant process water supplies and dewatering wells
- Geothermal use water supply wells
- Groundwater injection return wells (geothermal injection wells)
- Geothermal loop borehole construction
- Compressed air/gas injection well construction
- All types of services performed on existing wells, like renovation or rehabilitation services.
- All types of well service and pump repair on all types of water wells
- Development and test pumping on new or existing water supply wells
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How do I comply with GP6?
Iowa's NPDES
General Permit No. 6,*pdf requires the development of a site specific
well water pollution prevention plan,*pdf (WWPPP or Plan) for the each site where the discharge reaches a Water of the United States. Anytime that an engineer is used to develop the well plans, the engineer must also develop and create the WWPPP for the permittee. For wells that do not require the services of an engineer, the WWPPP can be developed by the well/landowner (permittee) or by a contactor or agent retained by the permittee to manage the WWPPP.
A WWPPP for the well construction or service event is designed to address the anticipated treatment needs for the wastewater that will be generated by the well project and then provide guidance for the implementation, inspection, and maintenance of any Best Management Practices (BMPs) or controls specified in the Plan. The Plan shall be written to adequately treat the wastewater before it enters conveyances, streams, rivers, and lakes and before it causes environmental problems. As the work on the well project is about to begin, the local regional IDNR Field Services Office must be notified using the
Field Office Notification Form (FON),*pdf.
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The Plan shall take into account items that will influence how the wastewater is managed, like:
- The location of the well on the landscape
- The limitations that the landscape provides for natural wastewater treatment
- The potential quantities and qualities of wastewater that may be generated during each phase of the construction or service work
- The best management practices (BMPs) used on and off of the construction site
- The strategic locations of all BMPs used
- Any adjustments or changes made to the BMPs after the initial installation
- Who inspects the BMPs, how often the inspections are performed, and what is found during the inspections
- And certification that all permittees and co-permittees fully understand what is required under GP6.
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What resources are available?
You can have updated Well Discharge Wastewater Information from the DNR sent directly to your email inbox as soon as the information is made available.
You should contact your local regional IDNR Field Services office. Please use the link below to determine the correct Field Office for your location and obtain the Field Office contact information.
Please check back periodically to obtain the latest information regarding well discharge wastewater or consider subscribing to the well discharge wastewater listserver.
