NC0062855_Performance Annual Report 2013_20140205

Mayor Lonnie B. English
Commissioners:
Mayor Pro-Tem A. H. Davis, Jr.
Joey Boswell
Terri Holt
Nikki Green
Kevin Stewart
February 5, 2014
TOWN OF ROBBINS
PO Box 296
Robbins, NC 27325
[phone]
Fax: [phone]
NC Division of Water Quality
NPDES Permit Issuing Authority
1617 Mail Service Center
Raleigh, NC 27699-1617
RE: System Performance Annual Report
NPDES Permit Number: NC0062855
Town of Robbins, Moore County, NC
Dear Permitting Authority:
DENR-FRC
FEB 1 0 2014
Town Manager
Jeff Sheffield
Enclosed is the 2013-Annual Performance Report for the Town of Robbins Wastewater
Treatment Plant. We believe the report to be complete and accurate. Our customers will
be notified of the availability of the report through the local newspaper or water/sewer
bills.
A copy of this report has been forwarded to the Fayetteville Regional Office. If you have
any questions, or require more information, please contact us.
Sincerely,
Tommy Gibbons
Town of Robbins WWTP Manager/ORC

GENERAL INFORMATION
Facility/System Name: Town of Robbins Wastewater Treatment Plant
NPDES Permit Number: NC0062855
Collection System Permit Number: WQCS00124
Responsible Entity: Town of Robbins
CONTACT INFORMATION
Permittee: Jeff Sheffield, Town Manager
PO Box 296
Robbins, NC 27325
910-948-2431
WWTP ORC: Tommy Gibbons, WWTP Manager/ORC
PO Box 296
Robbins, NC 27325
910-948-3063
Collections ORC: A.H. Davis Jr.
PO Box 296
Robbins, NC 27325
910-948-2431
DESCRIPTION OF TREATMENT PROCESS
All wastewater is conveyed to the Robbins WWTP via a permitted collection system. The
collection system consists of approximately 8.4 miles of gravity sewer, 1.5 miles of force main,
and three duplex pump stations.
The Town of Robbins WWTP is an extended aeration facility. It has a design capacity of 1.3
MGD. Treatment is initiated at a preliminary treatment unit (headworks), which consists of a
grit removal unit, semi -cylindrical fine screen, and a manual bar screen. De -gritted and
screened wastewater is pumped to a secondary treatment unit. Dual activated sludge
treatment units are provided with integral center -feed clarifiers. Mixing and aeration are
provided by diffused aeration. Caustic soda is added at the head of the system to add alkalinity.
Aluminum sulfate is added prior to the clarifiers to facilitate setting of the solids and to help
remove phosphorus. Clarified effluent is disinfected by chlorination, and then de -chlorinated
with sulfur dioxide. Settled sludge is either returned to the system as Return Activated Sludge
or wasted to an aerobic digester for further stabilization. After digestion is completed, the
stabilized sludge is land applied in liquid form onto permitted land application sites. The

effluent from the wastewater treatment plant is discharged into the Deep River, in the Cape
Fear River Basin.
COMPLIANCE PERFORMANCE
The Town of Robbins WWTP and Collection System are regulated by the NC Department of
Environmental and Natural Resources (NCDENR). The Town holds -a National Pollutant
Elimination System (NPDES) permit that includes water quality limits and sample monitoring
requirements. The NPDES permit requires the Town to test more than 15 different constituents
in the treated water. The monitoring frequency for these constituents are set at various
intervals such as continuous, daily, weekly, two times per week, monthly, and quarterly.
The Wastewater Treatment Plant consistently achieves 92-99% efficiency of removal of BOD
and TSS. The following is a summary of the testing for parameters that are assigned Water
Quality Standards -by the NPDES permit.
Please Note: The summary may not include parameters that only incorporate a monitoring
requirement, nor does it include daily process control testing.
Effluent Characteristics
Flow
Biochemical Oxygen Demand
Total Suspended Solids
Ammonia (NH3 as N)
Dissolved Oxygen
PH
Temperature °C
(Excluding weekends and holidays)
Fecal Coliform
Total Chlorine Residual
Conductivity
Oil & Grease
#Required
Continuous
52
52
52
52
52
249
52
104
52
13
(dropped from permit effective 03/31/2013)
Total Nitrogen
Total Phosphorus
Total Copper
(Total Copper monitoring reduced by permit from monthly to quarterly effective 03/31/2013)
#Conducted
Continuous
52
52
52
296
299
365
53
135
52
13
12
52
6
12
52
12

Total Mercury 4 4
Chronic Toxicity 4 4
In addition to the required testing, the Town conducted approximately 1,500 in-house control
tests to ensure the proper operation of the wastewater treatment plant. Some of the plant
control tests were PH, temperature, ammonia, alkalinity, nitrates, dissolved oxygen, settle
ability, suspended solids, and oxygen uptake rate.
SUMMARY OF PERMIT VIOLATIONS
Permit violations that occurred at the WWTP during 2013 were 13 occasions where the "total
chlorine residual" was in access of the "Daily Maximum Limit" of 28 ug/I, however all 13 were
under 50 ug/I and are still considered to be compliant.
May 2013 there was a "Weekly" Fecal Coliform violation of 593/100 ml. The Robbins WWTP
limit for this testing parameter is 400/100 ml for a weekly average (geometric mean). This
occurrence was due to heavy rainfalls 5/5/13 through 5/11/13 that in turn caused brief periods
of hydraulic overloading.
November 26, 2013 there was a "Weekly" Fecal Coliform violation of 900/100 ml. The Robbins
WWTP limit for this testing parameter is 400/100 ml for a weekly average (geometric mean).
This occurrence was due to a crack in the Sodium Hypochlorite discharge tubing. As a result the
chlorine failed to reach the top of the contact chamber, prohibiting proper disinfection. In
addition further testing for the week was not able to be performed due to our contract lab
closing for the Thanksgiving holidays.
Additional Notes:
Town of Robbins WWTP equipment is aging and several repairs need to be made. WWTP staff
has worked diligently this year on plant maintenance and making whatever repairs that could
be made. Notably the 300,000 gallon digester is offline due to needing a replacement blower.
This digester has been offline for several years. Quotes for repair have been obtained by WWTP
ORC, from Charles Underwood Assoc. and Carolina Technical Services. Currently there is not a
set date for repairs to begin on this project due to cost and budget.
WWTP has four 100 hp, main aeration blowers and currently 2 of these blowers are offline, 1 of
which has been down for more than 3 years.
December 2013 the 100,000 gallon digester 12" fill valve broke. This 12" plug valve will need to
be replaced immediately as neither of the plant digesters are operational right now. WAS is
being diverted to main treatment aeration basin #1 until repairs can be made. SKC contractors

in Seagrove, NC havebeen assigned this repair. As of 2/5/14 no planned date of repair has been
scheduled.
WWTP gas chlorination system was taken offline due to failing submersible pumps in effluent
well. This was designed to use reclaimed water, however the 4" submersible pumps would not
hold up to any debris in effluent discharge. During periods of heavy rainfalls the pumps
repeatedly clogged and failed resulting in high repair costs. After several attempts to repair
WWTP ORC took the gas chlorination offline and switched to liquid Sodium Hypochlorite for
disinfection and Sodium Bisulfite for dechlorination. Charles Underwood is handling the repairs
and coordinating approval from Infrastructure Finance/ NCDENR to make this switch
permanent and Permit compliant.
June 2013 treatment basin #1 was found to be inoperable due to clogged lines. The 20"
overflow that feeds the clarifier is clogged and attempts to unclog piping with jetter have failed.
This basin hasn't been used for treatment in more than 3 years and cause of clogging has yet to
be determined. Duck weed is now spreading through basin #1 and due to water not moving.
ORC has consulted with engineers to find resolution to the issue.

CERTIFICATION
I have personally examined the 2013 Annual Performance Report for the Town of
Robbins Wastewater Treatment Plant and I am familiar with the information
contained therein. Based upon my inquiry of the individuals immediately
responsible for obtaining the information reported herein, I . believe that the
submitted information is true, accurate, and complete. l_am aware that there are
significant penalties for submitting false information.
Signed this .'.� 'h day of f�c-c�
Jeffery A. Sheffield, Town Manager
, 2014