NC0088226_Meeting Notes_20210729

Permit NCOO88226
Duke Dewatering and GW Remediation System
Telephone Log regarding conversations about elevated Copper and Lead being found in the Effluent of
the treatment system.
• December 2020 the facility failed Chronic Toxicity Test NC NOV-2021-TX-0005 was issued by Water Quality
Group.
• January 2021: Chris Orrell (ORC), Ed Watson at the MRO DWR to inform the MRO know about the presence of
elevated Monthly Lead and elevated Daily Copper and Monthly copper. The initial thought was that the system
was drawing something from off -site as the system has a wide radius of influence for the GW remediation
system. The ORC was going to investigate to see if he could locate anything that may be contributing to the
system form offsite. Ed Watson of the MRO was in agreement with that action and requested to be kept
informed of any findings.
• February 2021: Ed Watson Received a phone call from Chris Orrell, to inform MRO that an outside source for
the elevated Copper and lead was not discovered. They are looking at components within the treatment system
to see if they can identify where the elevated metals may be resulting from. Some of the treated water from the
system is sent to the HVAC system for cooling the building. One thought is that return water may be
contributing to the elevated metal presence.
• March 2021: Ed Watson contacted Chris Orrell to get an update on the investigation of what may be causing the
elevated metals. Chris indicated that sampling had been performed at various portions of the treatment system
and it appeared that effluent water testing clean up to the Reverse Osmosis filter. That would have to wait to
take another sample to confirm that the RO filter was that source of the elevated metals.
• April 2021: In a call from Chris Orrell, the sample results came back as being elevated for Copper and Lead after
the RO filter. Water was being kept in a holding tank. The effluent release to the outfall was diverted to being
discharge before the RO filter as that water tested clean to 2B Surface Water standards for all constituents. A
new RO filter was ordered.
• May 2021: Chris Orrell contacted Ed Watson by phone to inform him that the new RO filter had been installed.
However, there was still elevated Copper in the effluent from the old RO filter that had not purged form the
treatment system.
• June 2021: An email was received for the Water Quality lab staff that the facility had Passed the Chronic Toxicity
testing for the first time in 2021. However, BIMS still indicates elevated Copper and Lead being present.