NC0027103_Influent Bypass_20061206

Pembroke NC0027103
Subject: Pembroke NC0.027103
From: Don Register <[e-mail]>
Date: Wed, 06 Dec 2006 14:35:59 -0500
To: Don Register <[e-mail]>, Hughie White <Hughie:[e-mail]>, Belinda
Henson <[e-mail]>, Dale Lopez <[e-mail]>, Mark Brantley
<[e-mail]>
ORC Rhonda Locklear called to report a bypass that occured at the influent pumpstation last night.
The problem was caused by a power interuption and the SCADA not having an operable UPS. This is
to be repaired tomorrow and also a high level float is to be installed in the pumpstation wetwell and
the alarm condition reported to the police station. The bypass was estimated at 200,000 gallons.
Don Register
Wastewater Treatment Consultant
NCDENR-Division of Water Quality
Surface Water Protection Section
Fayetteville Regional Office
[phone]
1 of 1 12/6/2006 2:46 PM

Dec 13:06 02:59a KAREN T. DIAL
910-521-1221 p.1
Town of Pembroke
POST OFFICE BOX 866
PEMBROKE, NORTH CAROLINA
28372
MILTON R. HUNT
MAYOR
McDUFFIE CUMMINGS
MANAGER
AMIRA HUNT
CLERK
December 1 1.2006
Ms. Belinda Henson
NCDENR-Fayetteville Regional Office
Division of Water Quality
225 Green Street
Suite 714 Systel Building
Fayetteville, NC 28301
Re: Manhole Overflow at WWTP
December 6, 2006
Dear Ms. Henson:
COUNCILMEN:
LARRY BROOKS
LARRY McNEILL
GREGORY CUMMINGS
ALLEN G. DIAL
Upon arrival at approximately 7:20 a.m. on December 6, 2006 Jerry Brooks, Back-up ORC, found the digester
manhole overflow. He immediately began plant checks and found the PLC for the Influent Pump Station had
failed as well as the clarifier skimmer arm. Both were reset and normal operation resumed.
The difference of flow allows us to believe that and estimated 200,000 gallons was released, however no visual
evidence of stream impact was noted upon site investigation. Ground saturation stopped @ 36 feet prior to
stream. Upstream and downstream fecal, pH, and dissolved oxygen analyses verified no impact. An inflatable
plug was placed in manhole and the area was lined for disinfection.
The Public Works Director informed us that a utility pole was hit around 4:30 p.m. and the repair was complete
at 8:00 p.m. We feel confident that a power surge caused the Influent PLC to fail and not reset. Javier,
engineer with CITI, installed a UPS on December 7. This would keep continuous power to the Influent Pump
Station PLC, effectively preventing future PLC failure due to power surges. He found that the telemetry could
not use the phone line to alert operator of alarms. The phone line had so much static that calls could not be
dialed. Bellsouth repaired the line the same day. Telemetry will be tested and recorded monthly.
The Town of Pembroke has plans to install a float system that will serve as an alternate control for the influent
pumps. We expect completion within the next six months. The facility also ordered a valve to place in the
manhole as another precaution.
We deeply regret this event and feel the actions taken will stop future occurrences. Please call with any
questions that you have.
Sincerely,
?X 6: // � C
Rhonda Hagan Locklear, ORC
Cc: McDuffie Cumming, Town Manager, Garry Harris, Public Works Director

Dec 13.06 02:57a
KAREN T. DIAL 910-521-1221 p.2
(EXPERT
SERVICES
INTERNATIONAL. LLC
Job Site Name:
Contact Name:
ES' Engineer
Start Date:
End Date:
Work Performed:
Calibration D
Service CategoryL
Start -Up Ull
MaintainingExceffeuce Through Superior Service
4030 Yancey Road, Charlotte, NC 28217
P.O. Box 37047, Charlotte, NC 28237
TECHNICAL ACTIVITY REPORT
Pembroke WWTP Fax:
Mrs. Rhonda Locklear Phone:
Javier Varela ESI Job Number.
12-7-06
12-7-06
Time of Arrival:
Time of Departure:
10:30 AM P.O. Number:
5:00 PM Bill To:
Software PLC El Software SCADA n Hardware n
Warranty Out of Warranty Q Training n
Verbal R.L.
City of Pembroke
Update Drawings fn
Troubleshooting fn
Description of work performed:
Met with Rhonda and Jerry at the plant and discussed the status of the influent pump station.
On the week of December 5, a power surge tripped the PLC panel at the station, locking the
processor into a "Halt mode, in this mode the PLC had no control over the pumps or the level
in the clear well. Also, Jerry informed me that the autodialer had not reported any of the alarm
statuses. He had reset the influent PLC panel as well as the clarifier control panel.
Troubleshooting steps taken:
1. Checked out the influent pump station PLC and found no errors present.
2. Verified the 120 VAC and the 480 VAC power to the panel. Both were within the proper
range.
3. Tested the automatic control of pumps #1 & #2. Both performed properly.
4. Tested the signals to the autodialer. All signals displayed properly.
5. Tested the phone line. Found that the line did not have a dial tone.
Corrective actions taken:
1. Installed a back-up UPS unit at the influent PLC panel. The power to the PLC and the
level transmitter were isolated to be maintained by the UPS in the event of a power
surge or an outage.
2. The phone company was contacted, and a technician was sent in to troubleshoot the
phone line. As indicated by the technician, the problem was found at the entry point
drop. Rust had accumulated preventing the line from acquiring a dial tone. The phone
line was tested and the autodialer enabled. Several alarms were generated to verify
the proper operation of the autodialer.
NB
8.0
If any solid state component, or equipment was replaced, please list:
Part Number
Description
(1) One 120VAC — 750VA UPS
Back-up UPS
Date: Customers Signature:
Fellow up phone call required? (y/n): ❑
Work completed? YES
NO
Next visit Scheduled Date:
Billed as CITI
Billed as ESI
CITI Invoice No.
ESI Invoice No.
PHONE [phone]
email:intorFesi-11c.com
FAX [phone].