NC0055786_Compliance Evaluation Inspection_20230503

ROY COOPER
Governor
ELIZABETH S. BISER
Secretary
RICHARD E. ROGERS, JR.
Director
Will Hodges
City of Lexington
28 W Center St
Lexington, NC 27292
NORTH CAROLINA
Environmental Quality
May 3, 2023
Subject: Compliance Evaluation Inspection
Lexington Regional WWTP
NPDES WW Permit No. NCO055786
Davidson County
Dear Mr. Hodges:
Jesse Barnes, of the North Carolina Division of Water Resources (NCDWR), Winston-Salem Regional Office
(WSRO), conducted a compliance evaluation inspection of the Lexington Regional WWTP Facility on April
3, 2023. Mr. Steven James, Interim Operator in Responsible Charge (ORC), was present for the inspection.
The facility was found to be compliant with the subject permit. Inspection findings are detailed in the
attached Water Compliance Inspection Report.
Please be aware that the Division may take enforcement action against any permittee who fails to comply
with any requirement of their permit. Pursuant to NC General Statute (NCGS) 143-215.6A, a civil penalty
of not more than twenty-five thousand dollars ($25,000.00) may be assessed against any person who
violates or fails to act in accordance with the terms, conditions, or requirements of any permit issued
pursuant to G.S. 143-215.1.
If you have any questions or concerns, please do not hesitate to contact Mr. Barnes by phone at 336-816-
7351, or by email at [e-mail].
Sincerely,
DocuSigned by:
OD2D3CE3F1 B7456_.
Jennifer F. Graznak, Assistant Regional Supervisor
Water Quality Regional Operations Section
Winston-Salem Regional Office
Division of Water Resources, NCDEQ
Attachments:
1. Water Compliance Inspection Report, NCO055786
DffNorth Carolina Department of Environmental Quality I Division of Water Resources
oan caaouNn
Winston-Salem Regional Office 1 450 W. Hanes Mill Rd, Suite 300 I Winston-Salem, North Carolina 27105
M336.776.9800
oep.m.m or em�nmen� Qualm,

United States Environmental Protection Agency
Form Approved.
EPA Washington, D.C. 20460
OMB No. 2040-0057
Water Compliance Inspection Report
Approval expires 8-31-98
Section A: National Data System Coding (i.e., PCS)
Transaction Code NPDES yr/mo/day Inspection Type Inspector Fac Type
1 IN 1 2 u 3 I NCO055786 111 121 23/04/03 I17 18 LC] I 19 I s I 20L]
21111I I I I I I I II I I I I I I I I I I I I I I I I I I I I I I I II I I I I I r6
Inspection
Work Days Facility Self -Monitoring Evaluation Rating B1 QA ---------------------- Reserved -------------------
67
I 72 I ni I 71 I 74 79 I I I I I I I80
701 I 71 I LL -1 I I
LJ
Section B: Facility Data
Name and Location of Facility Inspected (For Industrial Users discharging to POTW, also include
Entry Time/Date
Permit Effective Date
POTW name and NPDES Dermit Number)
09:30AM 23/04/03
21/02/01
Lexington Regional WWTP
500 Glendale Rd
Exit Time/Date
Permit Expiration Date
Lexington NC 27292
12:30PM 23/04/03
25/04/30
Name(s) of Onsite Representative(s)/Titles(s)/Phone and Fax Number(s)
Other Facility Data
Steven S James/ORC/336-357-5090/
Name, Address of Responsible Official/Title/Phone and Fax Number
Contacted
Will Hodges,28 W Center St Lexington NC 27292//336-248-3922/
No
Section C: Areas Evaluated During Inspection (Check only those areas evaluated)
Permit 0 Flow Measurement Operations & Maintenar Records/Reports
Self -Monitoring Progran 0 Sludge Handling Dispo: Facility Site Review Effluent/Receiving Wate
Laboratory
Section D: Summary of Finding/Comments (Attach additional sheets of narrative and checklists as necessary)
(See attachment summary)
Name(s) and Signature(s) of Inspector(s) Agency/Office/Phone and Fax Numbers Date
Jesse Barnes DocuSigned by: DWR/WSRO WQ/336-776-9701/
5/3/2023
� B��� E
41797473D3194ED...
Signature of Management Q A Reviewer Agency/Office/Phone and Fax Numbers Date
Docusigned by:
DwR/wslto 336-776-9695 5/3/2023 6
2
"--D D E3F B7456
EPA Form 356$-�3 (�f ev -94) previous editions are obsolete.
Page#

NPDES yr/mo/day Inspection Type
NCO055786 I11 12I 23/04/03 117 18 i c i
(Cont.)
Section D: Summary of Finding/Comments (Attach additional sheets of narrative and checklists as necessary)
NPDES permit NC0055786 became effective February 1, 2021 and will expire at midnight on April 30,
2025. The facility was observed to be as described in the permit. The subject permit contains no
special conditions. Facility staff are able to monitor and restrict public access via gated fence and
video surveillance; however, due to the composting program on site, the facility is generally
accessible during traditional business hours. The inspector was granted access to all requested
areas for inspection.
All records were kept and maintained as required by the subject permit. DMRs, analytical results, lab
reports, chains -of -custody, the most recent annual compliance report, and ORC visitation logs were
all complete and readily available during the inspection. DMRs and laboratory results from August
2022 through December 2022 were reviewed to ensure accuracy of transcription and reporting, no
errors were found.
All field laboratory parameters are performed by certified laboratory #43. Parameters not performed
in house by lab #43 are performed by contracted lab #10, Environment 1 Inc. A cursory inspection of
the field laboratory was conducted with no concerns observed. The area was clean and data sheets
and instrument calibration records were readily available.
The plant was found to be generally clean with acceptable housekeeping during the inspection. Mr.
James stated that appropriate process control parameters are utilized, namely using a sludge judge
twice per shift to assess the sludge blanket depth in the aeration basin and keeps it between 1-3 feet.
Influent flow was being measured using a Siemens Hydroranger 200, which had been calibrated
annually and calibration records were available during the inspection. The last calibration was
completed on 11/16/22 by CITI, LLC. The influent flow meter appeared to be operating properly
during the inspection.
Influent sampling was being conducted with a composite sampler that appeared to be operating
properly during the inspection. Mr. James explained that the sampler is programmed to collect
constant volume aliquots of 100 mL at variable timing dependent on rate of flow. The tubing was
clean, and the temperature for sample storage was observed to be compliant at VC during the
inspection.
The components of the influent pump station appeared to be operating properly during the inspection
and no concerns were noted. Wet wells were free of excessive grease and all pumps were operable.
The pump station and its related alarms are monitored by the operators via SCADA. Float controls
and audiovisual alarms were not evaluated.
A mechanical bar screen system was in use during the inspection and appeared to be operating
properly. The primary bar screen had been recently added to the facility, so the previous system was
serving as a backup unit. The primary system appeared to be in good condition and appropriately
screening debris. Mr. James stated that screened debris is disposed of to a landfill.
The facility was utilizing a mechanical grit removal system, which appeared to be operating properly
during the inspection. The grit was free of excessive odor and is disposed of via dump truck to a
landfill as needed.
No dedicated grease removal equipment was in use during the inspection. Mr. James believes that
due to the efficiency of the mechanical bar screen and grit removal systems, excessive grease
typically does not enter the treatment plant.
As indicated on the list of facility components in the subject permit, the two primary clarifiers on site
are available for use if needed but were bypassed and not in use during the inspection. Since the
Page#

Permit: NCO055786
Inspection Date: 04/03/2023
Owner -Facility: Lexington Regional WWTP
Inspection Type: Compliance Evaluation
primary clarifiers are specified as "not in use" on the subject permit, the permittee should notify DWR
if the facility plans to actively utilize them in the treatment process.
Biological nutrient removal occurs in dual diffused aeration basins on site. Both aeration basins
appeared to be operating properly with minimal foam, no excessive grease or debris, and a typical
color and odor. At least one of the submerged air diffusers was not operating properly during the
inspection, but the majority were in service and aeration appeared to be adequate with no dead
zones. Mr. James indicated that alum is regularly added to the aeration basins to aid in phosphorus
removal.
Dual secondary circular clarifiers were in use during the inspection. Mr. James indicated that the
clarifiers are cleaned twice monthly. One clarifier had recently been cleaned and was in good
condition during the inspection. The other clarifier had some algal growth on the weirs and some
solids buildup around the center well, but no short circuiting was evident and the treatment process
did not appear to be impeded. Some pin floc was observed, but it was not excessive in nature.
Two aerated lagoons/polishing ponds were in use during the inspection to provide additional settling
time for solids and additional aeration for nutrient removal. The lagoons each contained two surface
aerators which appeared to be operating properly during the inspection. The lagoons were free of
excessive floating materials and the surrounding dikes were well -kept with low grassy vegetation, no
large woody vegetation, and no clearly visible evidence of animal burrows or other threats to
structural integrity of earthen dikes. Mr. James stated that the lagoons are dredged as needed.
An automatic liquid sodium hypochlorite feed system was being used for disinfection. The system is
monitored and adjusted by operators remotely via SCADA system. The bleach storage building
appeared to provide adequate containment. All equipment associated with the disinfectant feed
system appeared to be in good condition and operating effectively. The chlorine contact chamber
was free of excessive vegetation, algal growth, and short circuiting during the inspection. Treated
wastewater in the chlorine contact chamber appeared to be turbid during the inspection.
The automatic liquid sodium bisulfite de -chlorination feed system is housed in a dedicated building
adjacent to the similarly -constructed disinfection feed building. The de -chlorination feed system
appeared to be in good condition and operating properly during the inspection. The system is
typically monitored and operated remotely by operators via SCADA system. The liquid sodium
bisulfite is injected at the end of the chlorine contact chamber.
A post aeration system was in use during the inspection, just after the chlorine contact chamber and
de -chlorination. While the post aeration system appeared to be operating properly during the
inspecting, the treated wastewater within appeared to be highly turbid. An in -line turbidimeter was in
use and reading 136 NTU during the inspection. When asked about this, Mr. James indicated the
turbidimeter reading was erroneous and it needed to be cleaned. However, the treated wastewater in
the post aeration structure appeared to match the turbidimeter readout of 136 NTU.
Effluent sampling was being conducted with a composite sampler that appeared to be operating
properly during the inspection. Mr. James explained that the sampler is programmed to collect
constant volume aliquots of 100 mL with variable timing dependent on rate of flow. The tubing was
clean and the temperature for sample storage was observed to be compliant at VC during the
inspection.
The aerobic digesters and diffused air flotation unit were not evaluated during the inspection due to
Page#

Permit: NC0055786
Inspection Date: 04/03/2023
time constraints.
Owner -Facility: Lexington Regional WWTP
Inspection Type: Compliance Evaluation
Mr. James attested that the RAS and WAS pump system was in good working condition during the
inspection. He claimed that maintenance staff utilize a work order system and maintain all necessary
spare parts for repairs.
Wasted sludge is dewatered using a belt press system, which is housed in a dedicated building and
appeared to be operating properly during the inspection. Adequate solids storage is available on site
and the sludge cake appeared to have an appropriate moisture content. Sludge cake is used in the
composting process that takes place on site at the facility. The permittee maintains a land application
permit and sells compost mixed with the biosolids produced from the treatment plant.
Automatically activated standby power is available via an on -site diesel generator. The generator is
tested under load with primary power interrupted once monthly and runs for four hours per test. The
entire treatment plant can be powered with the backup generator.
The effluent pipe was accessible via a well -maintained right of way. During the inspection, the effluent
outfall pipe was submerged and not accessible for observation. However, dark turbid water was
observed and appeared to be coming from the effluent pipe. This observation was consistent with the
characteristics of the treated wastewater observed in the disinfection contact chamber and post
aeration basin during the inspection. Water near the effluent outfall was noticeably darker in color
and appeared more turbid than the water in the receiving stream. The permittee is not currently
required to conduct upstream or downstream sampling due to active participation in the local river
basin association.
Page#

Permit: NCO055786 Owner -Facility: Lexington Regional WWTP
Inspection Date: 04/03/2023 Inspection Type: Compliance Evaluation
Permit
Yes
No
NA NE
(If the present permit expires in 6 months or less). Has the permittee submitted a new
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application?
Is the facility as described in the permit?
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# Are there any special conditions for the permit?
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Is access to the plant site restricted to the general public?
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Is the inspector granted access to all areas for inspection?
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Comment: NPDES permit NCO055786 became effective February 1, 2021 and will expire at
midnight on April 30, 2025. The facility was observed to be as described in the permit.
The subject permit contains no special conditions. Facility staff are able to monitor and
restrict public access via gated fence and video surveillance: however, due to the
composting program on site, the facility is generally accessible during traditional
business hours. The inspector was granted access to all requested areas for
inspection.
Record Keeping
Yes
No
NA
NE
Are records kept and maintained as required by the permit?
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Is all required information readily available, complete and current?
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Are all records maintained for 3 years (lab. reg. required 5 years)?
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Are analytical results consistent with data reported on DMRs?
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Is the chain -of -custody complete?
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Dates, times and location of sampling
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Name of individual performing the sampling
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Results of analysis and calibration
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Dates of analysis
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Name of person performing analyses
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Transported COCs
■
Are DMRs complete: do they include all permit parameters?
■
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Has the facility submitted its annual compliance report to users and DWQ?
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(If the facility is = or > 5 MGD permitted flow) Do they operate 24/7 with a certified
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operator on each shift?
Is the ORC visitation log available and current?
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Is the ORC certified at grade equal to or higher than the facility classification?
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Is the backup operator certified at one grade less or greater than the facility
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classification?
Is a copy of the current NPDES permit available on site?
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Facility has copy of previous year's Annual Report on file for review?
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Page# 5

Permit: NCO055786
Inspection Date: 04/03/2023
Record Keeping
Owner -Facility: Lexington Regional WWTP
Inspection Type: Compliance Evaluation
Yes No NA NE
Comment: All records were kept and maintained as required by the subiect permit. DMRs
analytical results, lab reports, chains -of -custody, the most recent annual compliance
report, and ORC visitation lops were all complete and readily available during the
inspection. DMRs and laboratory results from August 2022 through December 2022
were reviewed to ensure accuracy of transcription and reporting, no errors were found.
Laboratory Yes No NA NE
Are field parameters performed by certified personnel or laboratory? 0 ❑ ❑ ❑
Are all other parameters(excluding field parameters) performed by a certified lab?
0
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# Is the facility using a contract lab?
0
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# Is proper temperature set for sample storage (kept at less than or equal to 6.0
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degrees Celsius)?
Incubator (Fecal Coliform) set to 44.5 degrees Celsius+/- 0.2 degrees?
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Incubator (BOD) set to 20.0 degrees Celsius +/- 1.0 degrees?
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Comment: All field laboratory parameters are performed by certified laboratory #43. Parameters
not performed in house by lab #43 are performed by contracted lab #10,
Environment
1 Inc. A cursory inspection of the field laboratory was conducted with no concerns
observed. The area was clean and data sheets and instrument calibration records
were readily available.
Operations & Maintenance
Yes
No
NA
NE
Is the plant generally clean with acceptable housekeeping?
M
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Does the facility analyze process control parameters, for ex: MLSS, MCRT, Settleable
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Solids, pH, DO, Sludge Judge, and other that are applicable?
Comment: The plant was found to be generally clean with acceptable housekeeping during
the
inspection. Mr. James stated that appropriate process control parameters are utilized,
namely using a sludge fudge twice per shift to assess the sludge blanket depth
in the
aeration basin and keeps it between 1-3 feet.
Flow Measurement - Influent
Yes
No
NA
NE
# Is flow meter used for reporting?
0
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Is flow meter calibrated annually?
0
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Is the flow meter operational?
0
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(If units are separated) Does the chart recorder match the flow meter?
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0
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Comment: Influent flow was being measured using a Siemens Hydroranger 200, which had been
calibrated annually and calibration records were available during the inspection. The
last calibration was completed on 11/16/22 by CITI, LLC. The influent flow meter
appeared to be operating properly during the inspection.
Influent Sampling
Yes No NA NE
Page# 6

Permit: NCO055786
Inspection Date: 04/03/2023
Influent Sampling
# Is composite sampling flow proportional?
Is sample collected above side streams?
Owner -Facility: Lexington Regional WWTP
Inspection Type: Compliance Evaluation
Is proper volume collected?
Is the tubing clean?
# Is proper temperature set for sample storage (kept at less than or equal to 6.0
degrees Celsius)?
Is sampling performed according to the permit?
Yes
No
NA
NE
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Comment: Influent samplinq was beinq conducted with a composite sampler that appeared to be
operating properly during the inspection. Mr. James explained that the sampler is
programmed to collect constant volume aliquots of 100 mL at variable timing
dependent on rate of flow. The tubing was clean, and the temperature for sample
storage was observed to be compliant at VC during the inspection.
Pump Station - Influent
Is the pump wet well free of bypass lines or structures?
Is the wet well free of excessive grease?
Are all pumps present?
Are all pumps operable?
Are float controls operable?
Is SCADA telemetry available and operational?
Is audible and visual alarm available and operational?
Yes
No
NA
NE
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•
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Comment: The components of the influent pump station appeared to be operatinq properly during
the inspection and no concerns were noted. Wet wells were free of excessive grease
and all pumps were operable. The pump station and its related alarms are monitored
by the operators via SCADA. Float controls and audiovisual alarms were not evaluated.
Bar Screens
Yes
No
NA
NE
Type of bar screen
a.Manual
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b.Mechanical
Are the bars adequately screening debris?
0
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Is the screen free of excessive debris?
0
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Is disposal of screening in compliance?
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Is the unit in good condition?
0
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Page# 7

Permit: NC0055786
Inspection Date: 04/03/2023
Owner -Facility: Lexington Regional WWTP
Inspection Type: Compliance Evaluation
Bar Screens Yes No NA NE
Comment: A mechanical bar screen system was in use during the inspection and appeared to be
operating properly. The primary bar screen had been recently added to the facility, so
the previous system was serving as a backup unit. The primary system appeared to be
in good condition and appropriately screening debris. Mr. James stated that screened
debris is disposed of to a landfill.
Grit Removal
Type of grit removal
Yes No NA NE
a.Manual
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b.Mechanical
Is the grit free of excessive organic matter?
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Is the grit free of excessive odor?
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# Is disposal of grit in compliance?
0 ❑
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Comment: The facility was utilizing a mechanical grit removal system, which appeared
to be
operating properly during the inspection. The grit was free of excessive odor and is
disposed of via dump truck to a landfill as needed.
Primary Clarifier
Yes
No
NA
NE
Is the clarifier free of black and odorous wastewater?
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0
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Is the site free of excessive buildup of solids in center well of circular clarifier?
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0
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Are weirs level?
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0
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Is the site free of weir blockage?
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Is the site free of evidence of short-circuiting?
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0
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Is scum removal adequate?
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Is the site free of excessive floating sludge?
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Is the drive unit operational?
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0
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Is the sludge blanket level acceptable?
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0
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Is the sludge blanket level acceptable? (Approximately'/4 of the sidewall depth)
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0
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Comment: As indicated on the list of facility components in the subject permit, the two primar
clarifiers on site are available for use if needed but were bypassed and not in use
during the inspection. Since the primary clarifiers are specified as "not in use" on the
subject permit, the permittee should notify DWR if the facility plans to actively utilize
them in the treatment process.
Aeration Basins
Mode of operation
Type of aeration system
Yes No NA NE
Ext. Air
Diffused
Page# 8

Permit: NCO055786
Inspection Date: 04/03/2023
Aeration Basins
Owner -Facility: Lexington Regional WWTP
Inspection Type: Compliance Evaluation
Is the basin free of dead spots?
Are surface aerators and mixers operational?
Are the diffusers operational?
Is the foam the proper color for the treatment process?
Does the foam cover less than 25% of the basin's surface?
Is the DO level acceptable?
Is the DO level acceptable?(1.0 to 3.0 mg/I)
Yes
No
NA
NE
•
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•
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•
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•
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Comment: Bioloqical nutrient removal occurs in dual diffused aeration basins on site. Both
aeration basins appeared to be operating properly with minimal foam, no excessive
grease or debris, and a typical color and odor. At least one of the submerged air
diffusers was not operating properly during the inspection, but the majority were in
service and aeration appeared to be adequate with no dead zones. Mr. James
indicated that alum is regularly added to the aeration basins to aid in phosphorus
,1
Secondary Clarifier
Yes
No
NA NE
Is the clarifier free of black and odorous wastewater?
0
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Is the site free of excessive buildup of solids in center well of circular clarifier?
0
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Are weirs level?
S
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Is the site free of weir blockage?
■
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Is the site free of evidence of short-circuiting?
0
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Is scum removal adequate?
0
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Is the site free of excessive floating sludge?
0
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Is the drive unit operational?
0
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Is the return rate acceptable (low turbulence)?
0
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Is the overflow clear of excessive solids/pin floc?
0
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Is the sludge blanket level acceptable? (Approximately'/4 of the sidewall depth)
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Comment: Dual secondary circular clarifiers were in use durinq the inspection. Mr. James
indicated that the clarifiers are cleaned twice monthly. One clarifier had recently been
cleaned and was in good condition during the inspection. The other clarifier had some
algal growth on the weirs and some solids buildup around the center well, but no short
circuiting was evident and the treatment process did not appear to be impeded. Some
pin floc was observed, but it was not excessive in nature.
Lagoons Yes No NA NE
Type of lagoons? Aerated
# Number of lagoons in operation at time of visit? 2
Page# 9

Permit: NCO055786
Inspection Date: 04/03/2023
Lagoons
Are lagoons operated in?
# Is a re -circulation line present?
Owner -Facility: Lexington Regional WWTP
Inspection Type: Compliance Evaluation
Is lagoon free of excessive floating materials?
# Are baffles between ponds or effluent baffles adjustable?
Are dike slopes clear of woody vegetation?
Are weeds controlled around the edge of the lagoon?
Are dikes free of seepage?
Are dikes free of erosion?
Are dikes free of burrowing animals?
# Has the sludge blanket in the lagoon (s) been measured periodically in multiple
locations?
# If excessive algae is present, has barley straw been used to help control the growth?
Is the lagoon surface free of weeds?
Is the lagoon free of short circuiting?
Yes No NA NE
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Comment: Two aerated lagoons/polishinq ponds were in use during the inspection to provide
additional settling time for solids and additional aeration for nutrient removal. The
lagoons each contained two surface aerators which appeared to be operating properly
during the inspection. The lagoons were free of excessive floating materials and the
surrounding dikes were well -kept with low grassy vegetation, no large woody
vegetation, and no clearly visible evidence of animal burrows or other threats to
structural integrity of earthen dikes. Mr. James stated that the lagoons are dredged as
needed.
Disinfection -Liquid
Yes
No
NA
NE
Is there adequate reserve supply of disinfectant?
0
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(Sodium Hypochlorite) Is pump feed system operational?
0
❑
❑
❑
Is bulk storage tank containment area adequate? (free of leaks/open drains)
■
❑
❑
❑
Is the level of chlorine residual acceptable?
❑
❑
❑
Is the contact chamber free of growth, or sludge buildup?
M
❑
❑
❑
Is there chlorine residual prior to de -chlorination?
❑
❑
❑
Comment: An automatic liquid sodium hvpochlorite feed system was beinq used for disinfection.
The system is monitored and adjusted by operators remotely via SCADA system. The
bleach storage building appeared to provide adequate containment. All equipment
associated with the disinfectant feed system appeared to be in good condition and
operating effectively. The chlorine contact chamber was free of excessive vegetation,
algal growth, and short circuiting during the inspection. Treated wastewater in the
chlorine contact chamber appeared to be turbid during the inspection.
Page# 10

Permit: NC0055786 Owner -Facility:
Inspection Date: 04/03/2023 Inspection Type:
Lexington Regional WWTP
Compliance Evaluation
De -chlorination
Yes
No
NA NE
Type of system ?
Liquid
Is the feed ratio proportional to chlorine amount (1 to 1)?
❑
❑
❑
Is storage appropriate for cylinders?
❑
❑
0
❑
# Is de -chlorination substance stored away from chlorine containers?
0
❑
❑
❑
Are the tablets the proper size and type?
❑
❑
0
❑
Comment: The automatic liquid sodium bisulfite de -chlorination feed system is housed in a
dedicated building adjacent to the similarly -constructed disinfection feed building. The
de -chlorination feed system appeared to be in good condition and operating properly
during the inspection. The system is typically monitored and operated remotely by
operators via SCADA system. The liquid sodium bisulfite is injected at the end of the
chlorine contact chamber.
Are tablet de -chlorinators operational? ❑ ❑ 0 ❑
Number of tubes in use?
Comment:
Aerobic Digester
Yes
No
NA
NE
Is the capacity adequate?
❑
❑
❑
■
Is the mixing adequate?
❑
❑
❑
Is the site free of excessive foaming in the tank?
❑
❑
❑
# Is the odor acceptable?
❑
❑
❑
# Is tankage available for properly waste sludge?
❑
❑
❑
■
Comment: The aerobic diqesters and diffused air flotation unit were not evaluated durinq the
inspection due to time constraints.
Pumps-RAS-WAS
Yes
No
NA
NE
Are pumps in place?
0
❑
❑
❑
Are pumps operational?
❑
❑
❑
■
Are there adequate spare parts and supplies on site?
0
❑
❑
❑
Comment: Mr. James attested that the RAS and WAS pump system was in good working condition
during the inspection. He claimed that maintenance staff utilize a work order system
and maintain all necessary spare parts for repairs.
Solids Handling Equipment
Yes
No
NA
NE
Is the equipment operational?
0
❑
❑
❑
Is the chemical feed equipment operational?
❑
❑
❑
Is storage adequate?
■
❑
❑
❑
Page# 11

Permit: NC0055786 Owner -Facility: Lexington Regional WWTP
Inspection Date: 04/03/2023 Inspection Type: Compliance Evaluation
Solids Handling Equipment
Yes
No
NA
NE
Is the site free of high level of solids in filtrate from filter presses or vacuum filters?
0
❑
❑
❑
Is the site free of sludge buildup on belts and/or rollers of filter press?
0
❑
❑
❑
Is the site free of excessive moisture in belt filter press sludge cake?
■
❑
❑
❑
The facility has an approved sludge management plan?
❑
❑
❑
Comment: Wasted sludqe is dewatered using a belt press system, which is housed in a dedicated
building and appeared to be operating properly during the inspection. Adequate solids
storage is available on site and the sludge cake appeared to have an appropriate
moisture content. Sludge cake is used in the composting process that takes place on
site at the facility. The permittee maintains a land application permit and sells compost
mixed with the biosolids produced from the treatment plant.
Standby Power
Is automatically activated standby power available?
Is the generator tested by interrupting primary power source?
Is the generator tested under load?
Was generator tested & operational during the inspection?
Do the generator(s) have adequate capacity to operate the entire wastewater site?
Is there an emergency agreement with a fuel vendor for extended run on back-up
power?
Is the generator fuel level monitored?
Yes No NA NE
• ❑ ❑ ❑
• ❑ ❑ ❑
• ❑ ❑ ❑
❑ ❑ ❑ ■
■ ❑ ❑ ❑
❑ ❑ ❑ ■
■ ❑ ❑ ❑
Comment: Automatically activated standby power is available via an on -site diesel generator. The
generator is tested under load with primary power interrupted
once monthly and runs
for four hours per test. The entire treatment plant can be powered
with the backup
generator.
Flow Measurement - Effluent
Yes
No
NA
NE
# Is flow meter used for reporting?
0
❑
❑
❑
Is flow meter calibrated annually?
0
❑
❑
❑
Is the flow meter operational?
0
❑
❑
❑
(If units are separated) Does the chart recorder match the flow meter?
❑
❑
0
❑
Comment:
Effluent Sampling
Yes
No
NA
NE
Is composite sampling flow proportional?
0
❑
❑
❑
Is sample collected below all treatment units?
0
❑
❑
❑
Is proper volume collected?
0
❑
❑
❑
Is the tubing clean?
0
❑
❑
❑
Page# 12

Permit: NCO055786
Inspection Date: 04/03/2023
Effluent Sampling
Owner -Facility: Lexington Regional WWTP
Inspection Type: Compliance Evaluation
# Is proper temperature set for sample storage (kept at less than or equal to 6.0
degrees Celsius)?
Is the facility sampling performed as required by the permit (frequency, sampling type
representative)?
Comment:
Effluent Pipe
Is right of way to the outfall properly maintained?
Are the receiving water free of foam other than trace amounts and other debris?
If effluent (diffuser pipes are required) are they operating properly?
Yes No NA NE
■ ❑ ❑ ❑
❑ ❑ ❑
Yes
No
NA
NE
•
❑
❑
❑
•
❑
❑
❑
❑
❑
■
❑
Comment: The effluent pipe was accessible via a well -maintained right of way. During the
inspection, the effluent outfall pipe was submerged and not accessible for observation.
However, dark turbid water was observed and appeared to be coming from the effluent
pipe. This observation was consistent with the characteristics of the treated wastewater
observed in the disinfection contact chamber and post aeration basin during the
inspection. Water near the effluent outfall was noticeably darker in color and appeared
more turbid than the water in the receiving stream.
Upstream / Downstream Sampling Yes No NA NE
Is the facility sampling performed as required by the permit (frequency, sampling type, 0 ❑ ❑ ❑
and sampling location)?
Comment: The permittee is not currently required to conduct upstream or downstream sampling
due to active participation in the local river basin association.
Page# 13