In 2015, the U.S. Environmental Protection Agency (EPA) issued a new rule addressing the handling, storage and disposal of coal combustion residuals (CCRs). CCRs are the materials that remain after coal is burned.
Two Big Sandy Plant ash storage sites are included in the CCR monitoring program:
- The bottom ash pond and
- The fly ash pond.
Big Sandy Plant ceased burning coal in 2015. At that time the facility was converted to burn natural gas. As a natural gas-fueled facility, the plant no longer produces CCR material. The bottom ash pond has been closed and the CCR material was removed. The fly ash pond is being closed in place with a cap.
- Coal Combustion Residuals Monitoring & Reporting
Kentucky Power has completed the first steps in the new groundwater monitoring program under this rule.
Kentucky Power took a series of groundwater samples at the boundaries of both ash storage sites. We took some samples before the groundwater passed beneath the ash storage sites. (The reports refer to this as up-gradient.) We took other samples after it passed beneath the sites (down-gradient). We used the data to establish baseline levels for 21 different substances in the groundwater. It is important to remember that variations in the level of these substances in groundwater are natural and occur for many reasons.
Moving forward, we will use these baselines to help determine if our ash storage sites are impacting the groundwater. We will watch to see whether there are changes in the amount of these substances before and after the groundwater flows beneath the ash storage sites. We also will watch whether levels of these substances vary from the baselines we observed.
The initial data at Big Sandy Plant show potential groundwater impacts very close to our storage sites. Using appropriate sampling and analysis methods, we found differences in the amounts of boron, calcium, chloride, fluoride, pH, sulfate and total dissolved solids in certain wells before and after the groundwater passed beneath the storage sites. The rule calls these indicator substances. They are used to determine whether additional analysis is needed.
Baseline sampling in some wells showed one or more results for arsenic, beryllium and radium above primary drinking water standards. One or more samples showing a higher concentration of a substance, even above a standard, does not mean that local drinking water is unsafe or that there is any impact from the ash storage site.
We are working to understand what the numbers mean. We will do additional monitoring and analysis to determine if there are groundwater impacts from our storage sites farther from the immediate area.
We proactively reached out and met with plant neighbors and community leaders to answer questions about the data collected so far and to discuss next steps.
Here’s how Kentucky Power conducted the monitoring:
- The bottom ash pond - five monitoring wells,
- The fly ash pond - 10 monitoring wells.
- Alternate Source Reviews
Independent third parties completed Alternate Source Reviews for the Big Sandy bottom ash and fly ash ponds. The reviews consider other factors that could impact sampling results as the groundwater passes the CCR storage sites.
This review process did not find an alternate source for groundwater impacts for either Big Sandy CCR storage site.
- Location Restrictions – New
The CCR rule established location restrictions for coal ash storage sites. It requires that storage site locations be evaluated regarding proximity to
- Groundwater aquifers,
- Fault areas,
- Seismic zones and
- Unstable areas (example: presence of quicksand).
AEP and Kentucky Power recently completed the required review of location restrictions for Big Sandy Plant’s CCR storage sites. This review found:
- The Big Sandy fly ash pond is separated from the uppermost aquifer by less than the five feet specified by the rule. It does meet the other four location restrictions.
- The Big Sandy bottom ash pond has been closed and the CCR material was removed prior to this requirement and therefore does not have a location restriction report.
- Next Steps
- Kentucky Power will continue to test water from all of these wells twice each year.
- If Kentucky Power determines that an ash storage site is impacting the groundwater, we will expand monitoring to show whether there are water quality impacts farther away from the storage site.
- Kentucky Power will analyze assessment monitoring results by January 2019. If this additional monitoring indicates that changes in groundwater quality are coming from our ash storage sites, we will seek public input as we develop a mitigation plan to address these impacts.
- Kentucky Power will continue activities to close the fly ash pond.
- Bottom Ash Pond
- Fly Ash Pond