NC0031879_Annual Report_20210219

WASTEWATER SYSTEM PERFORMANCE REPORT
January 1, 2020 — December 31, 2020
City of Marion Public Works Department
PO Drawer 700
Marion, NC 28752
[phone]

Description of Wastewater Treatment System
The City of Marion owns and operates a wastewater treatment system consisting of a wastewater
collection system and one wastewater treatment plant. The wastewater collection system
consists of the sewer lines, pump stations, and all of the related appurtenances required to convey
wastewater from the homes and businesses of customers to the wastewater treatment plant for
treatment. All of the wastewater transported by the collection system is treated at the Corpening
Creek Wastewater Treatment Plant, located at 3982 Hwy 226 South, Marion, NC, prior to
ultimate discharge into receiving water designated as Corpening Creek (Young's Fork Creek) in
the Catawba River Basin. This report summarizes the performance of the collection system and
Corpening Creek Wastewater Treatment Plant during Calendar year 2020.
Collection System
General Information
Facility/System Name:
Permit Number:
Operator in Responsible Charge (ORC)
Contact Information for ORC:
Total Miles of Pipe:
Miles of Pipe Cleaned During 2020
Number of Pump Stations:
City of Marion Wastewater Collection System
WQCS00075
Gary Cook, Utility Maintenance Superintendent
828-652-4224 [e-mail]
Approximately 85 (76 gravity and 9 force main)
9.02 miles (12% of the gravity portion)
22
Wastewater Conveyance and Sanitary Sewer Overflows (SSO)
During calendar year 2020, approximately 399.9 million gallons of wastewater were conveyed to
the Corpening Creek Wastewater Treatment Plant. Sanitary sewer overflows totaling 19,125
gallons, or 0.0048% of the total gallons conveyed, were reported to the NC Department of
Environmental Quality (DEQ). The SSO gallons per month were as follows:
MONTH
# of SSOs
GALLONS
MONTH
# of SSOs
GALLONS
January
1
2,800
July
0
0
February
1
3,800
August
1
3,700
March
0
0
September
2
971
April
0
0
October
2
4,284
May
2
3,570
November
0
0
June
0
0
December
0
0

Sanitary sewer overflow events in which the volume of wastewater reaching surface waters
exceeded 1,000 gallons are included in the monthly estimates above and are summarized
separately below:
Event #1
Date: January 25, 2020
Gallons: 2,800
Location: 95 Forsythe Street
Surface Water Name: Unnamed tributary of Lake James in the Catawba River Basin
Cause of the SSO: Broken force main
Corrective Actions Taken: Repaired force main
Known Environmental Impact of the SSO: None
Event #2
Date: February 6, 2020
Gallons: 3,800
Location: 115 Forsythe Street
Surface Water Name: Unnamed tributary of Lake James in the Catawba River Basin
Cause of the SSO: Inflow and infiltration from a severe natural condition (excessive rain)
Corrective Actions Taken: The City is working to identify and eliminate sources of inflow and
infiltration in the collection system.
Known Environmental Impact of the SSO: None
Event #3
Date: May 19, 2020
Gallons: 3,500
Location: Clinchfield Pump Station (280 Forsythe Street)
Surface Water Name: Unnamed tributary of Lake James in the Catawba River Basin
Cause of the SSO: Inflow and infiltration from a severe natural condition (excessive rain)
Corrective Actions Taken: The City is working to identify and eliminate sources of inflow and
infiltration in the collection system.
Known Environmental Impact of the SSO: None
Event #4
Date: August 3, 2020
Gallons: 3,700
Location: Clinchfield Pump Station (280 Forsythe Street)
Surface Water Name: Unnamed tributary of Lake James in the Catawba River Basin
Cause of the SSO: Inflow and infiltration from a severe natural condition (excessive rain)
Corrective Actions Taken: The City is working to identify and eliminate sources of inflow and
infiltration in the collection system.
Known Environmental Impact of the SSO: None

Event #5
Date: October 29, 2020
Gallons: 4,200
Location: Clinchfield Pump Station (280 Forsythe Street)
Surface Water Name: Unnamed tributary of Lake James in the Catawba River Basin
Cause of the SSO: Inflow and infiltration from a severe natural condition (Tropical Storm Zeta)
Corrective Actions Taken: The City is working to identify and eliminate sources of inflow and
infiltration in the collection system.
Known Environmental Impact of the SSO: None
Corpening Creek Wastewater Treatment Plant
General Information
Facility/System Name:
Permit Number:
Operator in Responsible Charge (ORC)
Total Gallons Treated in 2020:
Average Monthly Flow:
Average Daily Flow:
Maximum Daily Flow:
Minimum Daily Flow:
Description of Treatment Processes
Corpening Creek Wastewater Treatment Plant
NC0031879
Tim Horton, WWTP Superintendent
828-652-8843 [e-mail]
399.9 MG
33.3 MG
1.08 MGD
2.52 MGD
0.78 MGD
The Corpening Creek W WTP has a capacity of 3.0 MGD and the unit processes include
screening, grit removal, primary clarification, aeration, lime addition, tertiary filters, gravity
sludge thickeners, vacuum sludge filters, chlorine disinfection, sulfur dioxide dechlorination, and
step aeration. Solids are treated by aerobic digestion before being stored and eventually land
applied under permit WQ0019960. Treated wastewater effluent is discharged into Corpening
Creek (Young's Fork Creek) under permit NC0031879.

Summary of Permit Violations
A total of two permit violations were reported to the NC Department of Environmental Quality
(DEQ) during calendar year 2020. Each violation is summarized below:
Violation #1
Date: February 15, 2020 (weekly limits violation) and February 29, 2020 (monthly limits
violation)
Type of Violation: Exceeded weekly average Total Suspended Solids limit and monthly average
Total Suspended Solids limit
Cause of Violation: Settling process was upset due to high flows during a rain event
Corrective Actions Taken: Adjusted aeration and flow to reduce the impact of flow spikes
Violation #2
This violation consisted of the following limit exceedances:
Date
Type of Violation
Cause of Violation
Corrective Actions
5/21/2020
Effluent pH daily
Operator Error.
Operator was re -
minimum not reached
Failure to allow pH
trained
meter to stabilize
before taking reading.
5/23/2020
Effluent BOD —
Solids washed out
Followed standard
Weekly average
due to high flows
operating procedures
exceeded
from excessive rain
for high flow
operation
5/23/2020
Effluent Ammonia —
Solids washed out
Followed standard
Weekly average
due to high flows
operating procedures
exceeded
from excessive rain
for high flow
operation
5/23/2020
Effluent TSS —
Solids washed out
Followed standard
Weekly average
due to high flows
operating procedures
exceeded
from excessive rain
for high flow
operation
5/26/2020
Effluent Dissolved
Operator Error
Operator was re -
Oxygen — Daily
trained
minimum not reached
5/26/2020
Effluent pH — Daily
Operator Error.
Operator was re -
minimum not reached
Failure to allow pH
trained
meter to stabilize
before taking reading.
5/31/2020
Effluent TSS —
Solids washed out
Followed standard
Monthly average
due to high flows
operating procedures
exceeded
from excessive rain
for high flow
operation

Public Notification
This report shall be available on the City of Marion's web site (www.marionnc.org), at City Hall
(194 N. Main Street), and at the Public Works Facility (94 Shop Drive). A statement of
availability will be mailed to each customer.
Certification
I certify under penalty of law that this report is complete and accurate to the best of my
knowledge. I further certify that this report will be made available to the customers of the named
system.
r w
J. Brant Sikes
Public Works Director
City of Marion Public Works Department
Date