WQCS00060_NOV-2023-DV-0071_20230224

(6'ou/i,
DEPARTMENT OF PUBLIC UTILITIES
PO BOX 2263
SMITHFIELD, NC 27577
[phone]
February 24, 2023
Mr. Scott Vinson
Raleigh Regional Office
NCDEQ DWR
1628 Mail Service Center
Raleigh, NC 27699-1628
Re: Response to NOV-2023-DV-0071
Permit No. WQCS00060 - Johnston County Collection System
Dear Mr. Vinson:
In response to NOV-2023-DV-00711, the County offers the following information:
Incident Number 202300150:
• On January 27, 2023, staff at the Johnston County Wastewater Treatment Plant identified a
failure near the influent where wastewater is received from the County's Landfill Wastewater
Pump Station/Equalization Facility.
• Johnston County staff immediately responded and shut-off the Landfill Wastewater Pump
Station/Equalization Facility pumping into the force main, stopping the sewer spill.
• County staff contacted one of the County's Emergency On -Call contractors to excavate the site.
Upon excavation, staff noted corrosion of 12" force main where it discharged into the on -site
manhole. Staff determined the spill was caused by material failure of the 20 year -old ductile
iron 12" force main.
• The spill was recovered by vacuum truck to the extent possible.
• While the force main was shut -down, the equalization basin at the upstream Landfill
Wastewater Pump Station was used to hold flow until the force main was placed back in service.
• The contractor removed and replaced the failed ductile iron pipe.
• The accidental and unintentional spill was a result of ductile iron pipe failure of the force main
pipe material.
Johnston County works aggressively to prevent sanitary sewer overflows and help protect the waters of
our area. Preventative measures include the following:
• Routine visual inspection of the force main route and air release valves.
• Extensive staff training ensures staff is prepared for system operation and response related to
potential sewer spills.
• Updated County construction standards have been updated to minimize the use of ductile iron
pipe within the County's sewer system. All ductile iron pipe installed contains an interior
corrosion resistant interior coating.
• Staff use laptops to log into the SCADA system and monitor system operation from any location.
• Furthermore, staff is on -call and prepared to respond to any event.

Page 2
Mr. Vinson
February 24, 2023
• The County maintains an in-house supply of repair materials for all pipe sizes and many
electrical components and implements a detailed protocol for emergency response.
• The County maintains an Emergency On -Call contract with several contractors to provide
emergency repair services.
Johnston County takes seriously our responsibility to protect public health and the environment and
strives to prevent sewer spills. Please contact me at [phone] or
[e-mail] if you have any questions or need additional information regarding
this issue.
Sincerely,
Chandra C. Farmer, PE
Director of Utilities
cc: Rick J. Hester, County Manager
Eric Narron, Johnston County
William Denton, Johnston County
Dan Wall, Johnston County
Vanessa Manuel, Raleigh Regional Office
Mitchell Hayes, Raleigh Regional Office