NC0067342_Other Agency Documents_20190212

J��'(ED STgp�s UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
REGION 4
Z Science and Ecosystem Support Division
z Field Services Branch
° 980 College Station Road
�tirq< aRotEo��� Athens, Georgia 30605-2720
February 4, 2019
MEMORANDUM
SUBJECT: NPDES Diagnostic Evaluation Inspection Report Transmittal
Northview Mobile Home Park WWTP
Weaverville, North Carolina
SESD Project ID: 19-0067
FROM: Chris McHugh, Environmental Engineer
Enforcement Section
Field Services Branch
Science and Ecosystem Support Division
Athens, Georgia
THRU: John Deatrick, Chief -
Field Services Branch
Science and Ecosystem Support Division
Athens, Georgia
TO: Dennis Sayre, Acting Chief
Municipal and Industrial Enforcement Section
Water Protection Division
Atlanta, Georgia
Attached is a copy of the NPDES Diagnostic Evaluation Inspection (DE) Report for the inspection
conducted at the Northview Mobile Home Park WWTP located at Northview Park Road, Weaverville,
NC. The DE was conducted from November 26-28, 2018. The recommendations included in this report
reflect the operational conditions and configuration of the WWTP at the time of the EPA evaluation.
Suggestions and recommendations should be reviewed and implemented applicable to the current
WWTP unit processes. Please forward copies of the report to the appropriate parties. If you have any
questions concerning the diagnostic evaluation, please call me at [phone] or email me at
[e-mail].
Attachment:
Cc (via email): Mary Jo Bragan, USEPA, WPD, NPDES Permitting and Enforcement Branch
Andrea Zimmer, USEPA, WPD, NPDES Permitting and Enforcement Branch
Sara Schiff Janovitz, USEPA, WPD, State of North Carolina Pacesetter
Mary Mattox, USEPA, WPD, NPDES Permitting and Enforcement Branch

Project ID: 19-0067
NPDES Diagnostic Evaluation
Inspection Report
Northview Mobile Home Park WWTP
Northview Park Road
Weaverville, NC, 28787
Project Date: November 26-28, 2018
Report Date: February 4, 2019
Project Leader: Chris McHugh
Environmental Engineer, EIT
Enforcement Section
Field Services Branch
Science & Ecosystem Support Division
USEPA — Region 4
980 College Station Road
Athens, Georgia 30605-2720
The activities depicted in this report are accredited under the US EPA Region 4 Science and
Ecosystem Support Division ISO/IEC 17025 accreditation issued by the ANSI-ASQ National
Accreditation Board. Refer to certificate and scope of accreditation AT-1644.
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Requestor:
Dennis Sayre, Acting Chief
Municipal and Industrial Enforcement Section
NPDES Permitting and Enforcement Branch
Water Protection Division
USEPA — Region 4
61 Forsyth Street SW
Atlanta, GA, 30303-8960
Approvals:
SESD Project Leader:
Gam.- rLlh�
Chris McHugh, Environmental Engineer
Enforcement Section
Field Services Branch Science and
Ecosystem Support Division
Approving Official:
1
John Deatrick, Chief
Field Services Branch
Science and Ecosystem Support Division
Date
2-jq// el
Date
SESD ID: 19-0067 Final Report Page 2 of 31

Table of Contents
1. INTRODUCTION................................................................................................................. 4
2. BACKGROUND................................................................................................................... 4
3. SUMMARY AND RECOMMENDATIONSO.................................................................... 5
4. FACILITY SITE REVIEW................................................................................................. 7
5. PERMIT.................................................................................................................................8
6. FLOW MEASUREMENT................................................................................................... 8
7. SLUDGE HANDLING......................................................................................................... 9
8. SAMPLING.........................................................................................................................10
8.1 FACILITY SAMPLING......................................................................................................
10
8.2 USEPA SAMPLING ACTIVITIES......................................................................................
11
9. REFERENCES....................................................................................................................12
List of Tables
TABLE 1
- INSPECTION PERSONNEL...................................................................................... 4
TABLE 2
- FLOW MEASUREMENT DEVICE COMPARISON ................................................ 8
TABLE 3
— TOTAL FLOW RECORDED COMPARISON.......................................................
12
TABLE 4
- LEGEND FOR FIGURE 2........................................................................................
15
TABLE 5
— FLOW METER TOTALIZER COMPARISON.......................................................
17
List of Figures
FIGURE 1 - NORTHVIEW MOBILE HOME PARK WWTP FLOW DIAGRAM ................... 14
FIGURE 2 - NORTHVIEW MOBILE HOME PARK WWTP TREATMENT UNIT
DIMENSIONS...................................................................................................................... 15
FIGURE 3 — 24-HOUR FLOW DATA FROM EPA FLOW METER ........................................ 19
SESD ID: 19-0067 Final Report Page 3 of 31

NPDES Diagnostic Evaluation Inspection
Northview Mobile Home Park WWTP (Permit No. NC0067342)
1. Introduction
During the week of November 26, 2018, representatives of the U.S. Environmental Protection
Agency (USEPA) Region 4 Science and Ecosystem Support Division (SESD) and the North
Carolina Department of Environmental Quality (NCDEQ) conducted a National Pollutant
Discharge Elimination System (NPDES) Diagnostic Evaluation Inspection (DE) on Northview
Mobile Home Park Wastewater Treatment Plant (WWTP) in Weaverville, North Carolina. The
inspection was requested by the NCDEQ Asheville Regional Office to supplement the EPA
Diagnostic Evaluation Inspection conducted in July 2018 (Project ID 18-0570). This additional
evaluation of the plant's flow measurement system, NPDES sampling equipment, and sludge
handling procedures reflects the operation and configuration of the WWTP at the time of the
inspection. It is intended to provide technical recommendations to improve the plant's
performance. The following people listed in Table I participated in the inspection.
Table 1 - Inspection Personnel
Inspector
Organization
Date on site
Chris McHugh
USEPA Region 4 SESD
11/26/18 — 11/28/18
Louis Salguero
USEPA Region 4 SESD
11/26/18 11/28/18
Cornell Gayle
USEPA Region 4 SESD
11/26/18 — 11/28/18
Linda Wiggs
NCDEQ Asheville
11/26/18 — 11/27/18
Regional Office
Landon Davidson
NCDEQ Asheville
11/27/18
Regional Office
2. Background
The Northview Mobile Home Park WWTP is a privately -owned wastewater treatment plant that
serves the Northview Mobile Home Park, consisting of approximately 170 mobile homes. The
facility is designed to operate as an extended aeration plant and is permitted as of April 18, 2018,
to discharge 0.032 MGD to receiving waters designated as Flat Creek in the French Broad River
Basin. Currently, the facility is under a Statutory Tap Moratorium because it was deemed by the
SESD ID: 19-0067 Final Report Page 4 of 31

NCDEQ Asheville Regional Office as unable to adequately treat the volume of wastewater flow
it receives daily.
In July 2018, EPA Region 4 SESD personnel conducted a Diagnostic Evaluation of the
Northview Mobile Home Park at the request of the NCDEQ Asheville Regional Office. In
summary, the July inspection revealed an excessive amount of solids retained in the treatment
system and difficulties verifying the facility's flow measurement and sampling system was
adequate for collection of representative composite samples.
3. Summary and Recommendations
During the evaluation, an ISCO Signature Series flow meter and ultrasonic sensor were installed
and programmed to measure and record the facility's effluent flow rate. The meter collected flow
data for the duration of the inspection, and its calibration to the facility's primary flow device
(90' v-notch weir plate) was checked multiple times to ensure that the sensor was measuring
accurate flow data. Comparisons between the EPA installed flow meter totalizer and the
facility's flow meter totalizer, and instantaneous flow checks comparing the facility's flow
sensor and the EPA sensor were recorded throughout the inspection (see Table 2, PB260001,
P13260002, P13260003, and P13260004).
The facility's composite sampling equipment was evaluated to review the equipment accuracy to
properly collect a representative sample. Using a graduated cylinder and timer, EPA personnel
calculated the sampler's pumping velocity when collecting a sample aliquot. Additionally, the
sample refrigerator was evaluated to review the temperature preservation efficiency of a
composite sample during the composite period.
A sludge judge was used to measure the sludge blanket depth in the facility's circular clarifier
and polishing clarifier to evaluate the solids in the treatment system and to compare with the
previous inspection.
The major findings were as follows:
• The circular clarifier had a sludge blanket depth of 7.5 feet with 10 feet total depth, and
the polishing clarifier had 3.5 feet with 10 feet total depth.
• During the inspection, SESD observed that the circular clarifier weir plates were
submerged when the flow rate increased after the hourly aeration blower cycle (see
PB270021).
• The facility's flow measurement sensor was not within ± 10 % of the facility's primary
flow measurement device (90' v-notch weir plate), and based on the operator's
comments, the sensor had never been field calibrated to the weir plate (see section 6
below).
SESD ID: 19-0067 Final Report Page 5 of 31

• There was no permanently installed staff gage to measure the water level above the
weir plate.
• After each hourly aeration blower cycle, the facility's flow rate increased to a rate that
almost overtops the effluent weir plate, meaning the weir is not adequate to incorporate
the additional flow limit set forth in Section A. (2) of the facility's NPDES permit (see
PB270024).
• The skimmer arm in the circular clarifier was not skimming properly because it was
observed above the height of the surface water in the clarifier (see P13270014).
• The scum trough in the circular clarifier was below the water surface, allowing water to
freely drain through the valve to the digester (see P13270025).
• The effluent sample setup was not properly operating due to the position of the tubing
coming out of the effluent sample location and the way that it was routed (34 feet) via
PVC conduit to the composite sampler. After entering the sampler building, the tubing
had an unnecessary dip that could retain sample aliquot (see PB260012).
• Calculations using a graduated cylinder and stopwatch revealed that the effluent sample
setup was not adequate to collect a sample at the recommended velocity of 2 feet per
second (ft/s) to ensure that solids were not being retained in the tubing or excluded
from the sample.
• The facility's composite sampling set-up was not adequate to preserve the composite
sample to below 6° C as required in 40 CFR 136.3 Table II and SM 5210.B, and there
was no temperature measuring device inside the sample refrigerator to monitor the
temperature (see PB270016).
• There were noticeable amounts of floating solids and debris in the chlorine contact
chamber.
Recommendations are as follows:
• Continue to monitor sludge levels throughout the plant and waste more frequently to
prevent accumulation of solids in the clarifiers.
• Consider modifying the aeration basin blower schedule to better balance the on/off
cycle which will create a more stable environment for the microorganisms.
• Install a measurement device such as a staff gage so that the water level above the weir
can accurately and more easily be measured.
• Lower the height of the skimmer arm in the clarifier so that it can properly skim the
surface water to remove floating scum from the clarifier into the scum trough.
• Adjust the level of the scum trough relative to the surface water in the circular clarifier
so that the trough can properly remove scum.
• Modify the effluent sampling tubing setup so that there are no unnecessary bends or
troughs in the line that could prevent the sampler from collecting representative
samples.
• Modify the effluent sampling tubing setup so that the existing pump can collect a
sample at the rate of at least 2 ft/s by moving it closer to the effluent sampling location
or obtain a pump that is rated to collect a sample from the current distance of 34 feet at
a velocity of at least 2 ft/s.
SESD ID: 19-0067 Final Report Page 6 of 31

• Repair the existing refrigerator door seal or obtain a new sample refrigerator so that the
sample is properly preserved according to 40 CFR 136.3 Table II and SM 5210.B.
Proper temperature preservation will help prevent sample deterioration.
4. Facility Site Review
The WWTP is configured as an extended aerated system. Modifications to the original package
plant include the addition of the new aeration basin, circular clarifier, and contact chamber (See
Figure 1,2). Influent wastewater enters the plant and the flow is split between both aeration
basins and the equalization basin, followed by the circular clarifier. Afterwards, the circular
clarifier discharge goes into an Imhoff clarifier (now referred to as polishing clarifier). Some
flow is diverted back to the aeration basins (return activated sludge, RAS) and some is wasted to
the digester (waste activated sludge, WAS). The old chlorine contact chamber serves as an
additional retention unit before flow enters the new contact chamber, where tablets are used to
chlorinate and dechlorinate the effluent before final discharge.
Figure 1 in Appendix A shows the flow diagram of the facility as determined by the facility
operator and confirmed during the inspection. Table 5 lists the size of each treatment unit
measured during the inspection. The distance between the effluent sampling location and the
sampler was measured at 34 feet. This is discussed in section 8.1.
During the inspection EPA observed that the scum trough in the circular clarifier was completely
submerged and full of solids (see P13270013). After discussing the purpose of the scum trough,
the operator opened the waste valve of the scum trough and the solids were removed. Note the
trough was still submerged under the clarifier surface water (see PB270025).
Deficiency:
The clarifier scum trough is not properly located to remove the scum from the clarifier.
Requirement:
40 CFR, Part 122.41 (e), Proper Operation and Maintenance. The permittee shall at all times
properly operate and maintain all facilities and systems of treatment and control and related
appurtenances which are installed or used by the permittee to achieve compliance with the
conditions of this permit.
Recommendation:
The scum trough should be raised over the clarifier surface water. This allows the skimmer arm
to brush the floating scum into the trough and not allow the clarifier effluent water to flow freely
into the trough.
SESD ID: 19-0067 Final Report Page 7 of 31

5. Permit
The Northview Mobile Home Park WWTP permit (NC0067342) became effective on April 1,
2018 and will expire on March 31, 2023. Under the permit, the Eaven Brice Partnership can
operate an existing 0.032 MGD extended aeration wastewater treatment facility, and after
meeting other stipulations, operate a 0.050 MGD facility.
6. Flow Measurement
The facility's effluent flow system is composed of a 90 ° v-notch weir primary device and an
ultrasonic flow sensor as a secondary flow measurement device. At the time of the inspection,
the flow totalizer chart recorder was recording flow as compared to the previous July inspection
in which it was not operational (see PB260003). Shown in Table 2, comparisons between the
EPA and facility secondary flow sensors indicated an average flow measurement difference of
43.29%. Based on the calibration checks conducted during the inspection, it was verified that the
EPA sensor was within f 10% of the facility's primary weir device. Nonetheless, the facility's
secondary flow measurement device was not properly calibrated to the facility's primary weir
device. This indicates that facility is underreporting its flow measurement data by an average of
43.29%.
Table 2 - Flow Measurement Device Comparison
Flow Device
Device
Type
Flow (GPM)
Percent
Difference
Date and Time
EPA Ultrasonic sensor
Secondary
73.77
37.6%
11/26/18
9:00 a.m.
Facility Ultrasonic sensor
Secondary
46
EPA Ultrasonic sensor
Secondary
56.47
46.9%
11/26/18
9:05 a.m.
Facility Ultrasonic sensor
Secondary
30
EPA Ultrasonic sensor
Secondary
15.52
47.8%
11/26/18
9:25 a.m.
Facility Ultrasonic sensor
Secondary
8.1
EPA Ultrasonic sensor
Secondary
13.04
45.6%
11/26/18
9:26 a.m.
Facility Ultrasonic sensor
Secondary
7.1
EPA Ultrasonic sensor
Secondary
20.94
42.7%
11/27/18
9:22 a.m.
Facility Ultrasonic sensor
Secondary
12
EPA Ultrasonic sensor
Secondary
56.93
43.8%
11/27/18
12:17 pm.
Facility Ultrasonic sensor
Secondary
32
SESD ID: 19-0067 Final Report Page 8 of 31

EPA Ultrasonic sensor
Secondary
70
38.6%
12/27/18
17
13:pm.
Facility Ultrasonic sensor
Secondary
43
Average Percent Difference
43.29%
Deficiency:
The facility's flow meter is not properly calibrated to the facility's primary flow device (900 v-
notch weir) and consequently, is underreporting its effluent flow.
Regulatory Requirement:
40 CFR, Part 122.41 (e), Proper Operation and Maintenance. The permittee shall at all times
properly operate and maintain all facilities and systems of treatment and control and related
appurtenances which are installed or used by the permittee to achieve compliance with the
conditions of this permit.
Recommendation:
The facility should have its secondary flow measurement sensor calibrated on -site to match the
primary flow measurement device (900 v-notch weir). The first step is to install a staff level gage
on the side wall of the effluent contact chamber behind the weir to perform flow verification. As
recommended by the NPDES Compliance Inspection Manual 2017, a primary and secondary
flow measurement device should be calibrated to with a 10 % difference of each other.
7. Sludge Handling
The Northview Mobile Home Park WWTP uses a septic tank hauler company to dispose of the
treated sludge. At the time of the inspection, the circular clarifier had a sludge blanket depth of
7.5 feet. The total depth of the clarifier is 10 feet. Additionally, the polishing clarifier had a
sludge blanket of 3.5 feet with a total depth of 10 feet. The sludge blanket depth should be kept
to less than one-fourth of the clarifier sidewall water depth (CSU 2008). Based on the sludge
depth throughout the plant, the operator should gradually increase the amount of WAS. This will
lower the sludge blankets and prevent further solids loss during peak flow events. Managing the
return and waste of activated sludge is a critical component to properly operate an activated
sludge treatment system.
SESD observed that the sludge levels in the clarifiers were lower than the previous inspection.
However, the solids level in the aeration basin was noticeably higher. When the blowers were on
their off cycle, the solids level was approximately one to two feet below the water surface in the
aeration basin. During the previous inspection, this level of solids was not visible in the aeration
basin. While it is necessary to recycle solids from the clarifiers to retain healthy microorganisms
in the aeration basins, wasting solids is also critical to ensure that the solids are not being
SESD ID: 19-0067 Final Report Page 9 of 31

retained for too long in the treatment system. Old solids can lead to poor settling and cause
additional problems that will affect the plant's effluent quality. The reduction of solids in the
system will decrease the sludge blanket levels and prevent further solids loss during peak flow
events.
8. Sampling
8.1 Facility Sampling
As stated in the facility's NPDES permit, composite sampling is required twice a week for
biochemical oxygen demand (BOD5), total suspended solids (TSS), and NH3. Continuous
recording is required for Flow. The facility collects the effluent flow composite samples with a
Cole Parmer Masterflex pump, model 7024-72. During the inspection, SESD verified with the
pump manufacturer that this pump model was last manufactured in 2008 and has a maximum
capacity of 1700 mL/min and 600 rpm. To evaluate the sampler, EPA personnel conducted a
more in-depth evaluation of the sampler pump accuracy to collect representative samples.
Deficiencies:
The pump velocity was calculated using a graduated cylinder to measure the sample volume
collected and a timer to measure the collection time. With the measured flow rate and known
tube diameter (0.25-inch inner diameter), the pump velocity was calculated to be 0.4 feet per
second (ft/s) (see Appendix B for calculation).
The EPA observed unnecessary bends in the composite sampler tubing that could retain sample
aliquots, affecting the tubing purging process and sample representativeness. (see PB260012).
Additionally, the composite sample refrigerator door did not properly close, and no thermometer
was observed inside the refrigerator to monitor the sample temperature.
Regulatory Requirement:
40 CFR, Part 122.41 (e), Proper Operation and Maintenance. The permittee shall at all times
properly operate and maintain all facilities and systems of treatment and control and related
appurtenances which are installed or used by the permittee to achieve compliance with the
conditions of this permit.
40 CFR, Part 136 Table II, Required Containers, Preservation Techniques, and Holding Times
and SM 5210.B. Temperature should be below 6°C for sample preservation.
Recommendations:
The facility should reconfigure the setup so that the tubing can be placed in such way that there
is a gradual rise from collection point to the sampler.
SESD ID: 19-0067 Final Report Page 10 of 31

Also, samples need be collected at a velocity of at least 2.0 ft/s to avoid solids bias and to not
allow solids to settle. The facility should either move the existing sampling pump closer to the
effluent location or obtain a pump that can adequate achieve at least 2.0 ft/s to avoid solids bias
when collecting a sample.
Repair the existing refrigerator door seal or obtain a new sample refrigerator so that the sample is
properly preserved according to 40 CFR 136.3 Table II and SM 5210.B. The sample incubator
should be well -maintained. Also, the temperature should be monitored using a NIST traceable
thermometer and recorded. Proper temperature preservation will help prevent sample
deterioration.
8.2 USEPA Sampling Activities
An ISCO Signature Series flow meter and ultrasonic sensor were installed and programmed to
measure and record the facility's effluent flow rate. The sensor was set-up nearby the facility's
flow measurement equipment. The meter collected flow data for the duration of the inspection,
and its calibration to the facility's primary flow device (90' v-notch weir plate) was checked
multiple times to ensure that the sensor was measuring accurate flow data.
Throughout the inspection, the EPA flow meter totalizer and the facility's flow meter totalizer
were compared to evaluate if the facility's meter was properly totalizing flow. Table 3 shows the
comparisons in totalizer values throughout the inspection. Note the EPA totalizer was initially at
786 gallons, and the facility totalizer was at 3,050 gallons. These initial values were subtracted
from the comparison results to account for the initial difference in total flow between the
totalizers at the start of the comparison. For the duration of the inspection, the EPA flow totalizer
recorded 46,053 gallons, while the facility totalizer recorded 25,510 gallons. This 44.6 % percent
difference in recorded flow is consistent with the 43.29 % percent difference observed when
comparing instantaneous flow checks (see Table 2).
During the inspection, the facility's 24-hour flow was within permit limits. As shown in Figure 3
in Appendix C, the flow measured with the EPA flow meter during the 24-hour period from
11/26/18 13:30 to 11/27/18 13:30 p.m. was 0.026 million gallons (26,000 gallons).
Based on the data collected, the facility's flow measurement system is not properly calibrated to
the primary flow device (900 v-notch weir plate). Until it is properly calibrated, it is expected that
the facility will continue to underreport its total flow by upwards of 44.6%.
SESD ID: 19-0067 Final Report Page 11 of 31

Table 3 — Total Flow Recorded Comparison
EPA Totalizer
Facility Totalizer
Percent Difference
Date and Time
(gallons)
(gallons)
21,637
16,510
23.7 %
11/27/18
9:22 AM
24,422
18,520
24.2 %
11/27/18
12:30 PM
24,733
18,840
23.8 %
11/27/18
1:13 PM
46,053
25,510*
44.6 %
11/28/18
9:00 AM
* The Facility Totalizer appeared to not be recording flow when EPA personnel arrived on site to
compare totalizer values the morning of 11/28/18.
SESD conducted the field measurement activities following the Sample Analysis Plan (SAP)
prepared for the project. All USEPA sampling methods, measurements, and calibrations were
conducted in accordance with USEPA Region 4 SESD procedures listed in the SAP.
9. References
• "Operation of Wastewater Treatment Plants Vol 1 and 2", 7th Edition, CSU, Sacramento,
2008.
• "Teledyne Isco Open Channel Flow Measurement Handbook." 8a' Edition, Teledyne
ISCO, 2017.
SESD ID: 19-0067 Final Report Page 12 of 31

Appendix A: Facility Diagrams
SESD ID: 19-0067 Final Report Page 13 of 31

her
I7oeesler
Sp1l --
Thla le a dre�.'I, slow carl000 oii�cllll�. iloee
only fepment ftw, ooi a haL plp4.
Equalixaiio¢
New Amdom Basis
�
hasiro{F.Q�
3' r
�i
�l
CAdArraGom Basin
r
K
Pthnk e
d ulaecletJiler
Palietdeg clydll,e�
n ami* Not to Scale
----
WAS = Wx3 to Actuated Sludge
oidC oxtact
_------
RAS=RehuuActiyated Slue
}}+r+
C] doer
k
de-d char
Pipe is oewtev auiiell
Figure I - Northview Mobile Home Park WWTP Flow Diagram
SESD ID: 19-0067 Final Report Page 14 of 31

10' 12'
Front
Front 2
' ,
Middle 1 Middle
6'
=End
16'
End
10,
10,
C9)
4'
Figure 2 - Northview Mobile Home Park WWTP Treatment Unit Dimensions
Table 4 - Legend for Figure 2
Figure Label
Treatment Unit
Volume (ft3)
Volume (gallons)
1
Digester
400
3,000
2
Old Aeration Basin
3,600
26,928
3
Polishing Clarifier
1,360
10,175
4
Old Cl Contact Chamber
240
2,992
5
Equalization Basin
2,228
16,667
6
Clarifier
452
30,457
7
New Aeration Basin
7,140
53,411
8
New Cl Contact unused
900
6,732
9
New Cl Contact
900
6,732
10
Sampler Location
NA
NA
SESD ID: 19-0067 Final Report Page 15 of 31

Appendix B: Calculations and Raw Data
SESD ID: 19-0067 Final Report Page 16 of 31

Pump Velocity:
0022 * Q .0022 *. 0625 gpm
V= A = 2=0.4ft/s
Tc 0.2 5 inches.
4 * 12 inches
ft
V = velocity in feet per second (ft/s)
Q = flow in gallons per minute (gpm)
A = cross -sectional area of tubing in square feet (ft2)
Raw Flow Data:
The data below represents the total flow digital reading form both the EPA and facility totalizers
recorded throughout the duration of the inspection. This data was used to produce the
information in Table 3.
Table 5 — Flow Meter Totalizer Comparison
Flow Device
Device
Total Flow
Percent
Date and Time
Type
(gallons)
Difference
EPA Totalizer
Secondary
786
Initial
comparison
11/26/18
Facility Totalizer
Secondary
3,050
after setting up
1:34 PM
EPA totalizer
EPA Totalizer
Secondary
22,423
12.8%
11/27/18
9:22 AM
Facility Totalizer
Secondary
19,560
EPA Totalizer
Secondary
25,209
14.4%
11/27/18
12:30 PM
Facility Totalizer
Secondary
21,570
EPA Totalizer
Secondary
25,519
16.6%
11/27/18
1:13 PM
Facility Totalizer
Secondary
21,890
EPA Totalizer
Secondary
46,839
39%
11/28/18
9:00 AM
Facility Totalizer
Secondary
28,560*
* Facility Totalizer appeared to not be recording flow when EPA personnel arrived on site to
compare totalizer values the morning of 11/28/18.
SESD ID: 19-0067 Final Report Page 17 of 31

Appendix C: 24-hour Flow Chart
SESD ID: 19-0067 Final Report Page 18 of 31

NV MHP WWTP
11126118 - 11/27/18 24-Hour Flow Composite
Flow Rate (0.026 mgd);Total (0.026 mgal):0.03
4.12
1111
0.114
0.09
O.OS
E 0.06
0.05
0.04
0.0
0_02
a.a1
a
3PM BPM 9PM 27 Tue 3AM 0AM 9AM 12PM
Nov 26 Mon 2018 11/26/2018 1:30:00 PM - 11/27/2018 1:30:00 PM
Figure 3 — 24-hour Flow Data from EPA Flow Meter
SESD ID: 19-0067 Final Report Page 19 of 31

Appendix D: Photographic Log
SESD ID: 19-0067 Final Report Page 20 of 31

Photo Number
PB260001
Date Taken
11/26/18 9:25 AM
Author
Chris McHugh
Description
Facility Digital Instantaneous Flow
Measurement (8.4 gpm)
SESD ID: 19-0067 Final Report Page 21 of 31

Photo Number
PB260002
Date Taken
11/26/18 9:25 AM
Author
Chris McHugh
Description
EPA Flow meter instantaneous flow
measurement (15.52 gpm)
SESD ID: 19-0067 Final Report Page 22 of 31

V110
Photo Number
PB260003
Date Taken
11/26/18 9:26 AM
Author
Chris McHugh
Description
Facility Digital Instantaneous Flow
Measurement (7.1 gpm)
SESD ID: 19-0067 Final Report Page 23 of 31

�I :---4 _
Photo Number
PB260004
Date Taken
11/26/18 9:26 AM
Author
Chris McHugh
Description
EPA Flow meter instantaneous flow
measurement (13.04 gpm)
SESD ID: 19-0067 Final Report Page 24 of 31

Photo Number
PB260012
Date Taken
11/26/18 9:48 AM
Author
Chris McHugh
Description
Composite sampler tubing dip and PVC
conduit that is used to route tubing
underground to effluent sample location
SESD ID: 19-0067 Final Report Page 25 of 31

Photo Number
PB270013
Date Taken
11/27/18 7:52 AM
Author
Chris McHugh
Description
Circular clarifier skimmer and scum trough.
The trough was turned off and retaining scum.
SESD ID: 19-0067 Final Report Page 26 of 31

Photo Number
PB270014
Date Taken
11/27/18 7:53 AM
Author
Chris McHugh
Description
Circular clarifier skimmer elevated above
water level. The skimmer was not skimming
the scum off the top of the water surface as it
should.
SESD ID: 19-0067 Final Report Page 27 of 31

Photo Number
PB270016
Date Taken
11/27/18 8:12 AM
Author
Chris McHugh
Description
Facility's Composite Sampling Incubator, and
orange composite sampling container. The
deteriorating seal on the refrigerator door
made it difficult to keep the door completely
shut and no thermometer was present inside to
monitor sample temperature.
SESD ID: 19-0067 Final Report Page 28 of 31

Photo Number
PB270021
Date Taken
11/27/18 9:08 AM
Author
Chris McHugh
Description
Circular clarifier effluent weir trough with
flow surging above weir plate. This happens
every hour when the facility's aeration blower
system cycles off.
SESD ID: 19-0067 Final Report Page 29 of 31

Photo Number
PB270024
Date Taken
11/27/18 9:17 AM
Author
Chris McHugh
Description
Effluent weir with flow rising almost overtop
of the weir plate. This happens every hour
when the facility's aeration blower system
cycles off. The weir height is approximately 6
inches tall measured from the 90' v-notch to
the crest.
SESD ID: 19-0067 Final Report Page 30 of 31

s',
M-M�M
Photo Number
PB270025
Date Taken
11/27/18 9:25 AM
Author
Chris McHugh
Description
Circular clarifier skimmer and scum trough.
The trough was turned on during the
inspection to remove the retained solids. Note
the trough is completely submerged below the
top of the water column.
END OF REPORT
SESD ID: 19-0067 Final Report Page 31 of 31