Rockport Plant

September 2019

Indiana Michigan Power continues groundwater monitoring activities around Rockport Plant's coal ash storage sites. We analyze this data relative to EPA groundwater protection standards.

Analysis of this data by an independent third party indicates that these coal ash storage sites are not impacting groundwater quality.

We will continue groundwater monitoring at the Rockport Plant and will provide an update if we detect any samples above the EPA standards.

March 2018

Indiana Michigan Power (I&M) completed the first steps in the new groundwater monitoring program under this rule.

I&M 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. Moving forward, we will use these baselines to help determine if our ash storage sites are impacting the groundwater.

It is important to remember that variations in the level of these substances in groundwater are natural and occur for many reasons.

The initial data at Rockport Plant showed potential groundwater impacts very close to our storage sites. Additional groundwater monitoring did not indicate groundwater impacts from these sites.

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.

An independent third party successfully completed an Alternate Source Demonstration for the landfill at Rockport Plant. The review considers other factors that could impact sampling results as the groundwater passes the CCR storage sites.

The plant will continue sampling groundwater at the landfill to determine any future need for additional monitoring.

November 2018

The CCR rule established location restrictions for coal ash storage sites. It requires that storage site locations be evaluated regarding proximity to groundwater aquifers, wetlands, fault areas, seismic zones and unstable areas (example: presence of quicksand).

AEP and I&M recently completed the required review of location restrictions for Rockport Plant's CCR storage sites. This review found:

• The east pond of Rockport’s bottom ash pond complex is separated from the uppermost aquifer by less than the five feet specified by the rule. It does meet the other four restrictions.

• The west pond of Rockport’s bottom ash pond complex and the landfill meet all location restrictions.

• I&M will continue to test water from all of these wells twice each year.

• If, in the future, I&M determines that the ash storage sites are impacting the groundwater, we will seek public input as we develop a mitigation plan to address these impacts.

• We will stop placing CCRs in the Rockport east bottom ash pond as soon as an alternative can be made available. We then will begin closure activities.