EN25 Identity, size, protected status, and biodiversity value of water bodies and related habitats significantly affected by the reporting organization's discharges of water and runoff

[Will include discharges to 7Q10 zero flow streams or discharges to water bodies that are recognized by professionals to be particularly sensitive due to their size, function, or status as a rare, threatened or endangered system or support a threatened or endangered species.]  

While American Electric Power discharges approximately 18 billion cubic meters of process waste water per year, only one third of this water affects the receiving water bodies in any significant way.  Of this third, 53 percent, or 3.2 billion m3/yr, is non-contact cooling water discharged into Lake Michigan by the Cook Nuclear Plant (table below).  This discharge meets all water quality standards and, though biocides are periodically applied, it is treated and considered to be clean water.  However, this discharge is considered to be significant because it is released to Lake Michigan, which is designated as an Outstanding State Resource Water by Indiana and adjoining states.

Water bodies significantly affected by discharges of water

Water Body	Facility	Discharge Type	Reason for Significant Discharge Designation
Adair Run	Glen Lyn	Fly ash pond	>5% mean flow (effluent dominated water body)
Blockhouse Hollow	Cardinal	Fly ash pond	>5% mean flow (effluent dominated water body)
Clinch River	Clinch River	Waste water treatment	Multiple federally endangered mussels within the Clinch River
Dumps Creek	Clinch River	Ash dike seepage	>5% mean flow (effluent dominated water body)
Connor Run	Mitchell	Fly ash pond	>5% mean flow (effluent dominated water body)
East River1	Glen Lyn	Cooling water, ash transport, coal pile	>5% mean flow (effluent dominated water body)
Ginney Hollow1	Glen Lyn	Cooling water	>5% mean flow (effluent dominated water body)
Honey Creek	Rockport	Landfill runoff	>5% mean flow (effluent dominated water body)
Kanawha River	Kanawha River	Cooling water, ash transport water	>5% of mean flow; possible threatened or endangered freshwater mussels
Kyger Creek	Kyger Creek	Fly ash pond	>5% mean flow (effluent dominated water body)
Lake Michigan	Cook	Cooling water	Outstanding State Resource Water
Little Scary Creek	Amos	Fly ash pond	>5% mean flow (effluent dominated water body).
Muskingum River	Conesville	Cooling water	>5% of mean flow; Superior High Quality Water designation by Ohio due to high biodiversity and presence of numerous threatened and endangered mussels
Muskingum River	Muskingum River	Cooling water, ash transport water	>5% of mean flow; Superior High Quality Water designation by Ohio due to high biodiversity and presence of numerous threatened and endangered mussels
Muskingum River	Waterford	Cooling tower blowdown	Presence of threatened and endangered mussels
New River	Glen Lyn	Cooling water, ash transport	>5% of mean flow; Green floater mussel (federally threatened) found in New River drainage
New River2	Byllesby/ Buck	Cooling water, sump drains	Green floater mussel (federally threatened) found in New River drainage
New River2	Claytor	Cooling water, seal water	Green floater mussel (federally threatened) found in New River drainage; Fringed mountain snail (federally endangered) found in the near vicinity of the Claytor Project boundary
Roanoke River2	Leesville	Cooling water, seal water	Roanoke logperch (federally endangered fish) found in the Roanoke River drainage; the Pigg River has a relatively good population of Roanoke logperch and the river’s confluence is in Leesville Lake, between Leesville and Smith Mountain Dams
Roanoke River2	Niagara	Cooling water, bearing water	Roanoke logperch (federally endangered fish) found in the Roanoke River drainage
Roanoke River2	Smith Mountain	Cooling water, seal water	Roanoke logperch (federally endangered fish) found in the Roanoke River drainage; the Pigg River has a relatively good population of Roanoke logperch and the river’s confluence is in Leesville Lake, between Leesville and Smith Mountain Dams
Scioto River	Picway	Cooling water, ash transport	>5% of mean flow
Stingy Run	Gavin	Fly ash pond	>5% mean flow (effluent dominated water body)
Turkey Run	Gavin	Landfill leachate	>5% mean flow (effluent dominated water body)
Unnamed tributary of Ninemile Creek	Comanche	Cooling water	>5% mean flow (effluent dominated water body)

¹ These streams flow directly into the New River, which supports documented populations of federally threatened mussels.  The streams themselves serve mainly as conduits for the discharges and are not known to support rare or endangered aquatic life.

² These streams are listed because they support federally threatened and endangered species, however, the discharges to the streams are very small and of no consequence to the aquatic life. 

Other discharges constitute more than 99 percent of the flow of the receiving streams to which they are released, which makes these waste streams significant.  However, these discharges meet all applicable water quality standards and in many cases, have improved the quality of the receiving stream water.  For example, some receiving streams are impacted by acid mine drainage, making them acidic and unable to support aquatic life.  The addition of typically alkaline ash transport water improves the condition of these streams, allowing them to support viable aquatic communities. 

Other AEP discharges are released to water bodies that support federally-listed threatened and endangered species, in particular, freshwater mussels.  While not believed to be harmful, the discharges are listed due to the presence of these species. 

The remaining water bodies receive discharges that make up more than 5 percent of their mean annual flow.  While there is no evidence of harm to such systems, the volume of the discharged water makes the receiving streams vulnerable to water quality changes.  Two facilities in particular, the AEP Conesville and Muskingum River Plants, discharge heated cooling water to the Muskingum River and have the potential to affect fish populations in the river.

The NPDES permits for the Conesville (CV) and Muskingum River Plants (MRP) require that specified downstream water temperatures not be exceeded once the cooling water discharged from the plants mixes with the Muskingum River.   The temperature limits are needed to protect fish and other aquatic life from the adverse effects of high temperature.  Heat from power plants is regarded as a pollutant by state agencies, thus limitations on excessive heat pollution is necessary for environmental protection.

During certain conditions (low river flow and high river and air temperatures), generation must be carefully controlled to make sure that the total heat loading does not cause an excursion of downstream temperature limits.  This requires a real-time, continuous feedback of river temperatures downstream of the plants.  At MRP, temperature sensors have been installed across the river at a distance of one mile from the plant discharge.  The data from these sensors are used by plant staff to accurately assess downstream river temperatures and to make adjustments to protect the fish in the river.