WQCS00031_NOV-2020-DV-0193 Response_20200608

Orange Water and Sewer Authority
OWASA is Carrboro-Chapel Hill's not -for -profit public service agency
delivering high quality water, wastewater, and reclaimed water services.
June $, 2020 'NC Dept of Fnvironmental Quality
11 IN 1 ? 7020
Mr. Scott Vinson, Regional Supervisor Raleigh Regional Office
Water Quality Regional Operations Section
Raleigh Regional Office
Division of Water Resources. North Carolina Division of Environmental Quality
3800 Barrett Drive
Raleigh, North Carolina 27609
SUBJECT: Response to Notice of Violation (NOV-2020-DV-0193)
Sanitary Sewer Overflows — January, February, March 2020
Collection System Permit No. WQCS00031
Dear Mr. Vinson:
As requested in your letter of April 30, 2020 (received on May 8, 2020) we are writing to
provide you information about the (2) Sanitary Sewer Overflows cited in the above referenced
Ietter. These overflows were separate and unrelated. The incidents occurred on January 6, 2020
at 208 Clark Lake Road in Durham, North Carolina and January 8.2020 at l l5 South Road in
Chapel Hill, North Carolina.
1. Incident Number 202000030—1/6/20 Clark Lake Road
Background
The sewer infrastructure along Clark Lake Road was installed in 1988. It consists of precast
concrete manholes and a mixture of Ductile Iron and Vitrified Clay pipe. OWASA recently
cleaned and inspected the sewer infrastructure in 2014 and 2018. OWASA has no history of root
intrusion, sewer backups, or repairs in this area prior to this event.
Initial Response
On Monday, January 6, 2020, OWASA's Distribution and Collection Systems Coordinator
received a call from a customer reporting a possible water main break near address, 204 Clark
Lake Road. After receiving the complaint OWASA's Distribution and Collection System staff
responded to the incident and arrived at 8:39 a.m. noticing that it was in fact a sanitary sewer
overflow. Staff reported that upon arrival they noticed manhole 1838 overflowing and
wastewater was entering surface water near Clark Lake Road.
40OJone5 Ferry Road, Carrboro, NC 27SIO 0 919-968-4421 15 Info@owa,a.arg @OWASA3 i www.owasa.org

Mr. Scott Vinson
June 8, 2020
Page 2
Staff immediately alerted the Collection System Operator in Responsible Charge (ORC) and
mobilized remediation crews.
Investigations
OWASA staff opened both the upstream and downstream manholes in the area and determined
that blockage was isolated to one segment of sanitary sewer main.
OWASA staff alerted the Collection System ORC who arrived on the scene at 10:30 a.m. He
observed that the overflow had been stopped and that the wastewater had in fact reached surface
waters on Clark Lake Road.
OWASA staff also collected samples from the pond in various locations and found 4.9 mg/l of
ammonia in the bay closest to the spill site.
The ORC provided the initial spill response notification on 1/6/2020 at 1:30 p.m. to Jason T.
Robinson and the Colleclion Sj. lem Sanilary Sewer Overflow Reporting Form CS-SSO on
Friday, January 10"'.
Remediation
OWASA staff immediately began jetting the sewer main from the downstream manhole and
blockage was disencumbered at 9:06 a.m.
To remove the wastewater from the pond and lower the ammonia levels in the surface water,
OWASA installed a dewatering pump to discharge into a nearby sanitary sewer manhole. We
utilized a 6" pump near the area of the spill and dewatered until the levels came back under a 1.0
mgll which is considered "untraceable" by our Wastewater Treatment Plant laboratory. OWASA
staff collected multiple samples at various locations of the pond to ensure wastewater was
undetected.
OWASA staff applied pelletized lime and deodorant to the affected area to neutralize the
wastewater and covered with wheat straw.
On January 7, 2020, OWASA staff returned to the site and conducted video inspections of the
sanitary sewer lines and found a large root ball extending from manhole 1852 into the sewer
main. All roots were removed and lines were re -inspected to confirm that all blockages were
removed. Additionally, OWASA staffjetted the sanitary sewer mains in near proximity.
OWASA also had the manhole cone section treated with root control chemical.

Mr. Scott Vinson
June 8, 2020
Page 3
Root Cause of the Overflow
The sanitary sewer overflow was caused by a root mass that intruded into manhole 1838. This
intrusion blocked a large portion of the sewer main causing solids to collect upstream resulting in
a sewer backup that overflowed from the upstream manhole.
Efforts to Improve
Commitment to the highest level of environmental stewardship has been and continues to be one
of the fundamental principles of OWASA. We believe that OWASA's actions before, during,
and after the event reflect this commitment. OWASA requests that you consider these key
factors in any subsequent action the Division of Water Resources might take:
• OWASA staff addressed the issue immediately to minimize the impact
• OWASA met all reporting requirements
• OWASA treated the manhole cone section with root control chemical
• OWASA is continuously improving and updating our sewer preventative maintenance
program.
o We have treated 25 miles (7.6%), cleaned 162 miles (50%), and inspected 33
miles (10%) of our entire sanitary sewer system (327 miles) annually.
o This information gathered from our preventative maintenance program is used to
assist our Engineering Department with rehabilitation decision making which has
produced approximately 9.2 miles of sanitary sewer line replacement over the past
5 years.
OWASA staff collected samples at various locations of the surface water pond to ensure
that the dewatering system removed all the wastewater in the area.
2. Incident Number 202000045—118120 115 South Road
Backaround
The sewer infrastructure along South Road was replaced in 2009 as part of a renovation project
with the University of North Carolina at Chapel Hill. It consists of precast concrete manholes
and ductile iron pipe. OWASA recently cleaned he sewer infrastructure in 2019. OWASA has no
history of root intrusion or sewer backups in this area prior to this event.
Initial Response
On Wednesday, January 8, 2020, University of North Carolina Campus staff alerted OWASA's
Distribution and Collection Systems Manager, Jesse DuClau that manhole 20423 was
overflowing. OWASA staff arrived at the sanitary sewer overflow site at 1:03 p.m. Staff reported
that wastewater had reached a nearby storm drain.

Mr. Scott Vinson
June 8, 2020
Page 4
Investigations
OWASA staff opened both upstream and downstream manholes in the area and determined that
the blockage was located in manhole 20423, and the sewer service lateral for a nearby building.
The Collection System ORC, Nicholas Rogers, arrived on the scene at 1:03 p.m. I-Ie observed
that the overflow had in fact reached a surface water via the storm drain system discharge to
Chapel Creek.
OWASA provided the initial spill response notification on January 8, 2020, at 4:15 p.m. to
Mitchell S. Hayes and the Collection System Sani1awy.5eirei• Over lou, Repoi-ling Form CS SSO
on Friday, January 10"'.
OWASA staff atternpted to obtain video footage f-rom a nearby building for any evidence of
vandalism. However, the camera system was out of commission during the time of the overflow.
It was also noted that there was a large amount of construction being conducted in the nearby
building.
Remediation
OWASA staff noticed that the manhole was filled with gravel and other debris, and immediately
began jetting the sewer main from the downstream manhole and vacuuming out manhole 20423
utilizing the vac/jet combo truck. The manhole stopped overflowing at 1:31 p.m.
OWASA staff vacuumed out all the gravel and debris from the manhole. Then, OWASA staff
jetted the sanitary sewer main to remove any remaining debris. The staff also used sandbags to
dam the downstream storm drain culvert to contain the wastewater spill and used clean water to
flush the storm drain system. The contaminated water was pumped back into the sanitary sewer
system. Pre/post sampling was conducted to ensure wastewater was removed from the surface
water.
On January 9"', 2020, OWASA staff returned to jet the sewer main again and video inspected the
segment of main that had backed up to ensure there were not any additional blockages.
Root Cause of the Overflow
We believe that the overflow was due to vandalism because of the large amount of gravel and
debris that was present in a private sewer manhole as well as in manhole 20423.
Efforts to Imurove
Commitment to the highest level of environmental stewardship has been and continues to be one
of the fundamental principles of OWASA. We believe that OWASA's actions before, during,

Mr. Scott Vinson
.tune 8, 2020
Page 5
and after the event reflect this commitment. OWASA requests that you consider these key
factors in any subsequent action the Division of Water Resources might take:
• OWASA staff addressed the issue immediately to minimize the impact
• OWASA met all reporting requirements
• Vacuumed out our manhole, the private manhole, jetted sanitary sewer mains in near
proximity
• We communicated with construction management staff about the dumping of material
into manholes
We hope that the information provided herein is sufficient to understand the details of the events,
please feel free to contact us should you have any further questions.
Sincerely,
Ed Kerwin
Executive Director
cc: Todd Taylor, General Manager of Operations
Jesse DuClau, Distribution and Collection Systems Manager
Monica Dodson, Wastewater Treatment and Biosolids Recycling Manager
File
Attachments:
1. Clark Lake Road SSO report
2. Clark Lake Road Site map
3. South Road SSO report
4. South Road Site map

Attachment 1: Clark � LWS O Report
001 o� any jro State of North Carolina
Q Department of Environment and Natural Resources
DWR 11l� " 7�2 Division of Water Resources
1 QJction System Sanitary Sewer Overflow Reporting Form
DNhlonofWrtuImurces ...1► V CtpIOna Form CS-SSO
'4ia tip.
PART I:
This form shall be submitted to the appropriate DWQ Regional Office within five business days of the first knowledge of the
sanitary sewer overflow (SSO).
Permit Number: WQC800031 (WQCS# if active, otherwise use WQCSD#)
Facility: OWASA Collection System _ Incident #: 202000030
Owner. Orange Water and Sewer Authority_
City: Durham County: Orange Region: Raleigh
Source of SSO (check applicable): 0 Sanitary Sewer ❑ Pump Station / Lift Station
SPECIFIC location of the SSO (be consistent in description from past reports or documentation - i.e. Pump Station 6,
Manhole at Westall & Bragg Street, etc): 208 Clark Lake Rd
Manhole #: 1838
Latitude (Decimal Degrees): Longitude (Decimal Degrees):
Incident Started Dt: 01/06/2020 Time: 8:39 am Incident End Dt. 01/06/2020 Time: 09:06 am
(mm-dd-yyyy) (hh:mm AM/PM) (mm-dd-yyyy) (hh:mm AM/PM)-
Estimated Volume of the SSO: 945 gallons Estimated Duration (Round to nearest hour): 0:27 hours
Describe how the volume was determined: 35 GPM x 27 Min = 945 GAL
Weather conditions during the SSO event: sunny/dry
Did SSO reach surface waters? Yes ❑ No ❑ Unknown Volume reaching surface waters (gals): 945
Surface water name:
Did the SSO result in a fish kill? ❑ Yes R[No ❑ Unknown If Yes, what is the estimated number of fish killed?
SPECIFIC cause(s) of the SSO:
0 Roots
24 hour verbal notification (name of person contacted ): Jason T Robinson
DWR ❑ Emergency Mgmt Date (mm-dd-yyy): 01/06/2020 Time (hh:mm AMIPM): . 01.:30.00Pm
If an SSO is ongoing, please notify the appropriate Regional Office on a daily basis until SSO can be stopped.
Per G.S. 143-215.1 C(b), the responsible party of a discharge of 1,000 or more of untreated wastewater to surface waters
shall issue a press release within 24-hours of first knowledge to all print and electronic news media providing general
coverage in the county where the discharge occurred. When 15,000 gallons or more of untreated wastewater enters surface
waters, a public notice shall be published within 10 days and proof of publication shall be provided to the Division within 30
days. Refer to the reference statute for further detail.
The Director. Division of Water Resources, may take enforcement action for SSOs that are required to be reported to
Division unless it is demonstrated that:
1) the discharge was cause by sever natural conditions and there were no feasible alternative to the discharge; or
2) the discharge was exceptional, unintentional, temporary and caused by factors beyond the reasonable control of the
Permittee and/or owner, and the discharge could not have been prevented by the exercise of reasonable control.
Part II must be completed to provide a justification claim for either of the above situations. This information will be the basis
WHETHER OR NOT PART III IS COMPLETED A SIGNATURE IS REQUIRED AT THE END OF THIS FORM
CS-SSO Form Page: 1

PART 11:
ANSWER THE FOLLOWING QUESTIONS FOR EACH RELATED CAUSE CHECKED IN PART I OF THIS FORM AND
INCLUDE THE APPROPRIATE DOCUMENTATION AS REQUIRED OR DESIRED
COMPLETE ONLY THOSE SECTONS PERTAINING TO THE CAUSE OF THE SSO AS CHECKED IN PART I
(In the check boxes below, NA = Not Applicable and NE = Not Evaluated)
A HARDCOPY OF THIS FORM SHOULD BE SUBMITTED TO THE APPROPRIATE DWR REGIONAL OFFICE UNLESS IS
Roots
Do you have an active root control program on the line 1 area in question? Yes 10 No [:] NA ❑ NE
Describe
Line is ductile iron with no roots present. Roots entered at service connection in manhole.
Have cleaning and inspections ever been increased at this location because of roots' ❑ Yes [0 No NA ❑ NE
Explain-.
We have not had any evidence of root intrusion in the area prior to this incident.
What corrective actions have been accomplished at the SSO location (and
surrounding system if associated with the SSO)?
We removed the roots from manhole and the roots that extended into the mainline. We repaired the manhole at the area
where the roots entered.
What corrective actions are planned at the SSO location to reduce root intrusion?
We have since had the manhole treated for roots and Put on a list for continued preventive maintenance.
Has the line been smoke tested or videoed within the past year? Yes [0 No NA NE
If Yes, when?
Comments:
Line was videoed in 2014
System Visitation
ORC Yes
Backup ❑ Yes
Name:
Nicholas Rogers
Cart#
998691
Date visited:
01 /06/2020
Time visited:
10:30 AM
CS-SSO Form Page: 2

How was the SSO remediated (i.e. Stopped and cleaned up)?
We cleaned the line to unblock the stoppage. We cleaned up spill site and applied lime and deodorant to the affected arei
and covered with straw. We sampled the lake and found 4.9 m 11 of ammonia in at the s ill site. We took samples around
various spots in lake to determine if its read from original location. We found the affected area to be isolated to the on in
spill site. We pumped out area to lower our levels of ammonia, after 3 hours of pumping our levels were untraceable. We
videoed the line and found a root curtain blocking the downstream line in the manhole. We removed the roots for manhole
and re-videoed line and confirmed it was clear and no additional blockages were present.
As a representative for the responsible party, I certify that the information contained in this report is true and accurate to the
best of my knowledge.
Person submitting claim: Ted H Shaffer
Signature:
Telephone Number:
Date: 01/10/20 10:30 am
Title:
Any addition information desired to be submitted should be sent to the appropriate Division Regional Office within five days of I
knowledge of the SSO with reference to the incident number (the incident number is only generated when electronic entry of th
form is completed, if used).
CS-SSO Form Page: 3

Vp�
Se
T6.

Attachment 3: South Road SSO Report
State of North Carolina
DWR
Department of Environment and Natural Resources
Division or Water Resources
Collection System Sanitary Sewer Overflow Reporting Form
INvtslon of Water Resources Form CS-SSO
PART I:
This form shall be submitted to the appropriate DWQ Regional Office within five business days of the first knowledge of the
sanitary sewer overflow (SSO).
Permit Number: WQCS00031 (WOGS# if active, otherwise use WQCSD#)
Facility: OWASA Collection System Incident #: 202000045
Owner: Orange Water and Sewer Authority _
City: Chapel Hill County: Orange Region: Raleigh
Source of SSO (check applicable): O Sanitary Sewer ❑ Pump Station / Lift Station
SPECIFIC location of the SSO (be consistent in description from past reports or documentation - i.e. Pump Station 6,
Manhole at Westall & Bragg Street, etc): 115 South Road_ , Chapel Hill
Manhole #: 20423
Latitude (Decimal Degrees):
Longitude (Decimal Degrees):
Incident Started Dt: 01/08/2020 Time: 1:03 pm Incident End Dt: 01/08/2020 Time: 01:31 pm
(mm-dd-yyyy) (hh:mm AM/PM) (mm-dd-yyyy) (hh:mm AMIPM)
Estimated Volume of the SSO: 640 gallons Estimated Duration (Round to nearest hour): 0:28 hours
Describe how the volume was determined: 20 GPM x 32 MIN = 640 GAL
Weather conditions during the SSO event. sunny/dry
Did SSO reach surface waters? 0 Yes ❑ No ❑ Unknown Volume reaching surface waters (gals): 640
Surface water name: Chapel Creek
Did the SSO result in a fish kill? ❑ Yes ONo ❑ Unknown If Yes, what is the estimated number of fish killed?
SPECIFIC cause(s) of the SSO:
O Vandalism
24 hour verbal notification (name of person contacted ): Mitchell S Hayes
0 DWR ❑ Emergency Mgmt Date (mm-dd-yyy): 01/08/2020 Time (hh:mm AMIPM): 04:15:00 pm
If an SSO is ongoing, please notify the appropriate Regional Office on a daily basis until SSO can be stopped.
Per G.S. 143-215.1 C(b), the responsible party of a discharge of 1,000 or more of untreated wastewater to surface waters
shall issue a press release within 24-hours of first knowledge to all print and electronic news media providing general
coverage in the county where the discharge occurred. When 15,000 gallons or more of untreated wastewater enters surface
waters, a public notice shall be published within 10 days and proof of publication shall be provided to the Division within 30
days. Refer to the reference statute for further detail.
The Director Division of Water Resources may take enforcement action for SSOs that are required to be re orted to
Division unless it is demonstrated that:
1) the discharge was cause by sever natural conditions and there were no feasible alternative to the discharge; or
2) the discharge was exceptional, unintentional, temporary and caused by factors beyond the reasonable control of the
Permittee and/or owner, and the discharge could not have been prevented by the exercise of reasonable control.
Part II must be completed to provide a justification claim for either of the above situations. This information will be the basis
WHETHER OR NOT PART III IS COMPLETED A SIGNATURE IS REQUIRED AT THE END OF THIS FORM
CS-SSO Form Page: 1

PART II:
ANSWER THE FOLLOWING QUESTIONS FOR EACH RELATED CAUSE CHECKED IN PART I OF THIS FORM AND
INCLUDE THE APPROPRIATE DOCUMENTATION AS REQUIRED OR DESIRED
COMPLETE ONLY THOSE SECTONS PERTAINING TO THE CAUSE OF THE SSO AS CHECKED IN PART I
(In the check boxes below, NA = Not Applicable and NE = Not Evaluated)
A HARDCOPY OF THIS FORM SHOULD BE SUBMITTED TO THE APPROPRIATE DWR REGIONAL OFFICE UNLESS IS
Vandalism
Provide police report number:
Police are not involved at this time OWASA is still investigating and reviewing video footage from building security camer.
Was the site secured? [j] Yes No ❑ NA NE
If Yes, how?
It was secured with a manhole cover.
Have there been previous problems with vandalism at the SSO location? Yes JZ No [] NA [] NE
If Yes, explain:
What security measures have been put in place to prevent similar occurrences in the 2 Yes ❑ No [] NA ❑ NE
future?
Comments:
Manhole cover was replaced and site will be monitored closely by OWASA.
System Visitation
ORC
Backup
Name:
Nicholas Rogers
Cert#
998691
Date visited:
01 /08/2020
Time visited:
01:03 PM
How was the SSO remediated (i.e. Stopped and cleaned up)?
jo Yes
Yes
We cleaned out all the debris rocks and nravel from the manhole. We then cleaned the sewer main of any remainin
debris. A crew also used sandbags to dam up, the downstream side of the storm sewer pipe, parkinglot and storm sewer
was flushed with clean water and pumped the overflow into the sewers stem. Sewer lines were cleaned again on
01/09/2020 and line was videoed and found to be clear of any additional blockages.
CS-SSO Form Page: 2

As a representative for the responsible party, I certify that the information contained in this report is true and accurate to the
best of my knowledge.
Person submitting claim:
Signature:
Telephone Number:
Ted H Shaffer
Date: 01/10/20 11:20 am
Title:
Any addition information desired to be submitted should be sent to the appropriate Division Regional Office within five days of f
knowledge of the SSO with reference to the incident number (the incident number is only generated when electronic entry of th
form is completed, if used).
CS-SSO Form Page- 3