NC0025321_NOVNOI2020PC0245_RESP_20200618

Gavin Brown, Mayor Robert W. Hites, Jr. Town Manager
Gary Caldwell, Mayor Pro Tem William Cannon, Town Attorney
Jon Feichter, Alderman
Julia Freeman, Alderman
LeRoy Roberson, Alderman

6/18/2020

Mr. Landon Davidson, P.E., Regional Supervisor
Water Quality Regional Operations Section
Asheville Regional Office
Division of Water Resources, NCDEQ
2090 US Highway 70
Swannanoa, NC 28778

Re: Response to Notice of Violation & Intent to issue Civil Penalty
NOV-2020-PC-0425

Dear Mr. Davidson:

Thank you for providing the Town with an opportunity to respond to the Division’s NOV regarding the “Unauthorized Bypass” of 100,000 gallons of waste that occurred at our plant on April
30, 2020. I will outline the event, our immediate response and our plan to mitigate future overflows.

BYPASS OF PARTIALLY TREATED WASTE- WATER FROM PRIMARY EFFLUENT PUMP BUILIDNG AREA TO RICHLAND CREEK.

On April 30, 2020 the watershed received 1.41 inches of rain. During the storm the plant experienced several voltage surges and dropped a leg of a three- phase circuit from the transformer
Duke Power installed to provide the plant with power. The surges and single phases burned out the ABB drive knocking one of three effluent pumps out of service. Losing one of three
pumps during peak flows caused by the rain resulted in the effluent pump basin to overflow.

REMEDIATION OF BYPASS

The staff responded to the spill by bypassing the burned-out control and straight wiring the pump. They contacted the manufacturer who shipped a replacement ABB drive immediately. When
the drive arrived a factory, representative installed it.

The staff raked and spread lime in the area where the spill overflowed the basin. Some of the flows entered Richland Creek though no fish were killed as a result of the overflow.

Page 2.
NOV 2020-PC-0425 Response

LONG TERM SOLUTION

The Town has been experiencing more frequent surges and failures in the three-phase transformer that provides power to the plant. Duke Power has been called numerous times but has no
solution to the issue. The plant’s entire electric system will be replaced during the renovation. The improvements will most likely require Duke to install a different transformer configuration.
I have instructed McGill and Associates to include surge suppressors in the renovation design.

The Town has been using its new camera system to locate areas where the smoke testing has indicated inflow. While we have discovered several areas of infiltration, we have not discovered
areas of inflow. As the Town staff catalogs areas of inflow it will put them in a package and engage a contractor make repairs. The Town has included $300,000 in the upcoming budget
to remediate inflow/infiltration.
CONCLUSION

The spill was caused by an electric surge and dropping of a phase in transformer owned and maintained by Duke Power. The loss of a leg in the circuit burned out an ABB drive that was
still under warranty taking one of three effluent pumps out of service. The plant was experiencing inflow after a storm event that dumped 1.41 inches of rain in the watershed. Two pumps
could not keep up with the flow. The loss of power quality and the inflow were unavoidable.

The Town is in the midst to two projects that will provide a long-term solution to the spills. It has contracted with McGill and Associates to design a complete renovation of the plant
and has undertaken a remediation program that will reduce the inflow/infiltration that has plagued the collection system for many years.

The issues we are facing at the plant are difficult for any staff. One of our challenges is the inexperience of our plant staff. The supervisory staff have been in their current positions
for less than three years and are overwhelmed at the degree of challenge of rehabilitating both the plant and collection system. We have engaged retired plant operators to help train
the staff in plant operations.

We hope that this explanation has provided you with the information you requested. Please let us know if we can provide you with further information. We recognize that the overflow constitutes
a violation however we ask that you consider our immediate notification of the spill and our efforts to mitigate the overflow.

Please do not hesitate to contact me at my cell number 828-550-5238 should you have any questions:

Sincerely,
/
Robert W. Hites Jr. Town Manager