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SENT VIA ELECTRONIC MAIL ONLY: NO HARD COPY WILL BE MAILED.
June 30, 2021
Zelerie Rogers, Town Manager
Fontana Dam Village
E-mail: zelerie.rogers@fontanavillage.com
SUBJECT: Technical Assistance Inspection Report
Town of Fontana Dam WWTP
NPDES WW Permit No. NC0023086
Graham County
Dear Permittee:
The North Carolina Division of Water Resources conducted a Technical Assistance Inspection of the Town of
Fontana Dam WWTP on 6/01/2021. This inspection was conducted to access the facility for causes and
potential solutions to challenges operating the #1 Secondary Clarifier to meet compliance with the conditions
and limitations specified in NPDES WW Permit No. NC0023086. The findings and comments noted during this
inspection are provided in the enclosed copy of the inspection report entitled "Compliance Inspection Report".
A response to this inspection report is not required.
If you should have any questions, please do not hesitate to contact me with the Water
Quality Regional Operations Section in the Asheville Regional Office at 828-296-4500 or via email at
tim.heim@ncdenr.gov.
Sincerely,
Tim Heim, P.E., Environmental Engineer
Water Quality Regional Operations Section
Asheville Regional Office
Division of Water Resources, NCDEQ
ATTACHMENTS
Ec: LF
Dennis.Pillkington@fontanavillage.com
DocuSign Envelope ID: 5089D756-A2B0-47E1-AB88-DAF3F216FA2D
EPA
United States Environmental Protection Agency
Washington, D.C. 20460
Water Compliance Inspection Report
Form Approved.
OMB No. 2040-0057
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 N 52 NC0023086 21/06/01 D S31112171819 20
21 66
Inspection Work Days Facility Self-Monitoring Evaluation Rating B1 QA ----------------------Reserved-------------------
N67707172 73 74 75 80
Section B: Facility Data
Name and Location of Facility Inspected (For Industrial Users discharging to POTW, also include
POTW name and NPDES permit Number)
Town of Fontana Dam WWTP
Fontana Village Resort
Fontana Dam NC 28733
Entry Time/Date Permit Effective Date
Exit Time/Date Permit Expiration Date
10:00AM 21/06/01 17/11/01
Name(s) of Onsite Representative(s)/Titles(s)/Phone and Fax Number(s)
///
Daniel Dennis Pilkington/ORC/828-498-2271/
Other Facility Data
10:00PM 21/06/01 22/10/31
Name, Address of Responsible Official/Title/Phone and Fax Number
Zelerie Rogers,PO Box 128 Fontana Dam NC 287330128/Town
Administrator/828-498-2107/
Contacted
No
Section C: Areas Evaluated During Inspection (Check only those areas evaluated)
Other
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
Timothy H Heim DWR/ARO WQ/828-296-4665/
Signature of Management Q A Reviewer Agency/Office/Phone and Fax Numbers Date
EPA Form 3560-3 (Rev 9-94) Previous editions are obsolete.
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DocuSign Envelope ID: 5089D756-A2B0-47E1-AB88-DAF3F216FA2D
6/30/2021
6/30/2021
NPDES yr/mo/day
21/06/01
Inspection Type
D3111218
1
Section D: Summary of Finding/Comments (Attach additional sheets of narrative and checklists as necessary)
Tim Heim of the Asheville Regional Office performed a Technical Assistance Inspection concurrent
with a Compliance Evaluation Inspection (led by Lauren Armeni) of the WWTP on June 1, 2021.
Dennis Pilkington (ORC) and Jason Duke (BORC in training) assisted with the inspection.
Observations:
The ORC stated the Operation of the #1 Secondary Clarifier (#2 is not in service) sludge collector
drive results in the generation of unacceptably high TSS and has resulted in effluent permit
violations. Facility staff does not operate the clarifier drive to avoid generating violations. Sludge is
wasted from the clarifier by pumping to the digester or headworks.
This wastewater facility appears to be operating at the end or past its design life and many
components are experiencing significant wear. The facility also experiences significantly lower flows
than it was originally designed for, which can cause significant operating challenges. Due to influent
conditions beyond the control of the facility, MLSS in the aeration basin is maintained at a relatively
low concentration (<100 mg/L) compared to other similar facilities of this type. The facility receives a
significant amount of flow from backwashing of filters at the Water Treatment Plant, which may
contribute to the operating challenges.
The #1 Secondary Clarifier is a rectangular type with a gear and drive chain-based sludge removal
system. The ORCs have attempted to vary the sludge blanket depth and other common means of
adjusting conditions in this type of clarifier to improve conditions, but this has not led to an
improvement.
Potential Causes:
In the experience of the inspectors, this type of clarifier can be very difficult to operate and is known
to cause effluent issues when the sludge drive unit is operated. The composition of the sludge
blanket may also hinder settling and be vulnerable to re-suspension of suspended solids, which is
due to the influent wastewater quality and operating conditions.
Possible Solutions:
1. Replace or upgrade the clarifier and other related facility components.
This could be done by specifically selecting a new secondary clarifier for the type of conditions the
facility experiences (which are atypical), or replacement of the entire WWTP. This is the
recommended option.
2. Contact a qualified specialist to investigate plant operations, specifically influent characteristics
and the MLSS concentration in the aeration basin, and whether changes can be made to operate in
ranges more typical of a biological treatment process (> 1,500 mg/L is typically considered in the low
range). Improved biological treatment could result in improved sludge settling and removal
characteristics in the secondary clarifier.
3. Chemical Settling Aids.
It is possible that the addition of chemicals (polymers and/or settling aids) could improve sludge
blanket conditions and prevent re-suspension of solids during operation of the drive unit. This would
have to be evaluated by a specialist and require bench testing. This option is not recommended due
to long term cost, complexity, and potential for unintended adverse effects.
4. Alternate means of solids removal.
The operators could discontinue using the clarifier sludge removal drive system permanently and
attempt an alternative hydraulic/mechanical means of wasting solids from the clarifier that does not
NC0023086 17 (Cont.)
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DocuSign Envelope ID: 5089D756-A2B0-47E1-AB88-DAF3F216FA2D
Permit:NC0023086
Inspection Date:06/01/2021
Owner - Facility:
Inspection Type:
Town of Fontana Dam WWTP
Technical Assistance
result in effluent violations. This option is not recommended as a long term solution due to the
additional effort, equipment, and manpower involved. Normal treatment operations would also
potentially be disrupted.
Note: An additional component of concern is the manual bar screen. Current conditions require the
screen to be manually raked and for solids to dry in open air, which has the potential to create
nuisance conditions and a health hazard. It is recommended that this unit be upgraded to avoid these
conditions.
Page#3
DocuSign Envelope ID: 5089D756-A2B0-47E1-AB88-DAF3F216FA2D
Permit:NC0023086
Inspection Date:06/01/2021
Owner - Facility:
Inspection Type:
Town of Fontana Dam WWTP
Technical Assistance
Other Yes No NA NE
The ORC stated that the Operation of the #1 Secondary Clarifier (#2 is not in service)
sludge collector drive results in the generation of unacceptably high TSS and has
resulted in effluent permit violations. A TA investigation was performed at the request of
the ORC by the ARO Environmental Engineer (Heim).
Comment:
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DocuSign Envelope ID: 5089D756-A2B0-47E1-AB88-DAF3F216FA2D