NC0066516_Compliance Evaluation Inspection_20240403

FJQUAY-VAR ! NA
north caro6nc
April 3, 2024
Danny Smith
Water Quality Regional Operations Section
Raleigh Regional Office
Division of Water Resources, NCDEQ
1617 Mail Service Center, Raleigh, NC 27699-1628
RE: COMPLIANCE EVALUATION INSPECTION
Terrible Creek WWTP
NPDES NCO066516
Town of Fuquay-Varina
Wake County
Dear Mr. Smith,
Mike Wagner
Public Utilities Director
[e-mail]
The Town of Fuquay-Varina appreciates the opportunity to respond to the inspection evaluation
report dated March 4, 2024. It is our intent that this response will provide sufficient additional
information regarding the Division's request for the following information:
• Provide a detailed account of the repairs undertaken to repair BNR unit #2 and clarifier
unit #1 and a schedule for repairs to be completed.
TOFV Response:
Since the time the 3.0 MGD treatment facility was placed into service, the Town has had
numerous failures related to the mixers. Also, in 2022 and 2023, the Town started
experiencing problems with the two clarifiers. Enclosed is Exhibit A and Exhibit B that
will provide a detailed repair timeline for the BNR mixers and Clarifier # 1.
• Provide details on the repairs that remain to be completed on BNR unit #1 and
anticipated scheduled for the repairs to be completed.
TOFV Response:
Due to past mixer failures on both BNRs, Hayward Gordon decided to replace all
fourteen (14) mixer pedestals with heavier, more robust pedestals. Also, replacement
blades were ordered for the mixers in BNR #1 that had failed. On 3/3/24, the mixer
blades and mixer pedestals were installed by an authorized Hayward Gordon technician.
The same technician came back on 3/31/24 and grouted the mixer pedestal bases and
Hayward Gordon requested that we allow a week for the grout to cure. The mixers are
expected to be placed back into service on 4/5/24.
Public Utilities
Town of Fuquay-Varina 134 N. Main Street, Fuquay-Varina, NC 27526 [phone] fuquay-varina.org

Once the biological activity and process control parameters return to normal in BNR#1,
plant staff will take down BNR#2 for inspection purposes and to schedule installation of
seven mixer pedestals. The Town will also inspect mixer blades to ensure each one is
still intact.
As demonstrated the treatment personnel were responsive and took immediate action to respond
to the equipment failures and initiated corrective action with the manufacturer's representatives.
We believe this letter demonstrates the Town's commitment to comply with the NPDES permit
and to ensure the treatment plant equipment is properly maintained and functioning as intended.
Please do not hesitate to contact me if you have any questions or concerns.
Sincerely,
Michael Wagner
Public Utilities Director
Enclosures: Exhibit A and Exhibit B
Cc: file
Adam Stephenson, ORC

Exhibit A-BNR Mixer Repair Timeline
7-26-18 changed oil in mixers BNR # 1
7-27-18 changed oil in mixers BNR 2
10-21-18 mixer 1-3 fault overcurrent
Warranty Request November 15, 2018, Mixers 1-3 and 1-4 are inoperable and keep faulting on
overcurrent
12-4-18 Hayward Gordon onsite to perform warranty work
12-10-18 Reset mixer 1-2
12-19-18 overloads changed out on small mixers
12-27-18 mixer 1-4 overload turned up
12-28-18 Mixer 1-3 and 1-4 tripping out
1-11-19 Mixer 2-5 faulted, tripped
3-11-19 Mixer shafts are wobbling
3-26-19 Mixers grinding and shafts wobbling
4-28-19 First new gear reducer on site
"We apologize for the issues you have experienced with our mixers.
As discussed, we have ordered a new gear reducer to swap out which we are confident will be a
solution to the problem. Once we see that this solves the problem, we will swap out the other 13
reducers.
Please find the anticipated schedule:
Reducer Parts Arrive at the HG Factory: 3-25-2019
HG Assembly and Painting Ship: 4-8-2019
Installation and Testing: 4-15-2019 (2 days)"
6-19-19 mixer gear reducer swapped out and motor replaced
8-8-19 mixer 2-3 off excessive gearbox movement
8-28-19 drained BNR 2 to inspect for rags on mixer blades
10-14-19 all mixer gearboxes swapped out
11-4-19 mixer 1-4 tripped
11-12-19 mixer 2-5 faulted on overcurrent
11-18-19 Hayward Gordon (Mike) on site for mixer 1-6 repair
12-4-19 mixer 1-3 tripped

12-11-19 mixer 2-5 tripped
12-18-18 mixer 1-4 tripped
12-26-19 mixer 2-5 tripped
1-14-20 Mixers 1-2, 1-3, and 2-4 are out of service, they continue to trip out - I am sending a
follow up email to David Caton about these
1-16-20 Mixer 1-5 gearbox is moving and noisy
1-28-20 mixer 1-7 out of service sheared bolt
2-3-20 Hayward Gordon techs on site troubleshooting mixers
2-25-20 mixer 2-3 shears bolt off at base plate
3-5-20 repaired sheared anchors and modified gearbox plate
5-4-20 Mixer 1-7 has a major oil leak
5-6-20 Mixer 1-4 bolt sheared at base
5-14-20 Mixer 2-2 leaking oil
5-26-20 Hayward Gordon tech repairs oil seals and adds stabilizing bolts
5-30-20 mixer shears bolt at base plate
6-19-20 Bolt is sheared on gearbox footing
6-30-20 Hayward Gordon tech. postponed visit and repair until tomorrow
8-11-20 conference call with Hayward Gordon
9-14-20 vibration analysis on all mixers and shaft deflection readings
11-19-20 Hayward Gordon replacing 3 gear reducers
2-3-21 HG tech on site evaluating three new gear reducer replacements
2-28-21 HG evaluated the operation of those mixers with shaft deflection measurements,
vibration ect., and those mixers look good so far.
6-2-21 HG tech on site evaluating mixer performance
6-14-21 drained BNR 1
6-17-21 HG techs on site inspecting mixers
1-19-22
• Removed existing motors

• Removed all gear boxes and loaded for haul away
• Installed new gear boxes and new 1" thick adapter plates with new hardware at gearbox
base
• Installed new anchors where needed due to failed anchors
• Re -installed motors
• Re -installed shaft guards
• On Saturday, bumped the 13 mixers that were complete which resulted in some tripping
on overload at initial start
2-11-22 HG tech on site welding all mixer pedestals and bases
9-8-22 new coupling installed
3-5-23 (3) new base plates installed on BNR 2
7-26-23 replaced lip seal
9-11-23 deflection check on mixers
9-19-23 discovered broken mixer blades on BNR 1
2-21-24 broken mixer blades repaired
3-3-24 new mixer pedestals were installed on BNR 1,
3-31-24 grouting was finished on new mixers pedestals on BNR 1
4-5-24 plan to put BNR 1 back in service with new mixers

Exhibit B-Clarifier 1 Repair Timeline
1-10-23 center column plate replaced with thicker one under warranty
2-21-23 clarifier 1 out of service
3-13-23 coating clarifier #1
6-7-23 Scum pump removed and rubber scum scraper replaced
4-26-24 set to receive new scum pumps
5-2024 Plan to install new scum pump and put clarifier back in service