NC0025321_NOVNOI2023PC0150_RESP_20230505

16 South Main Street · P.O. Box 100 · Waynesville, NC 28786 Phone [phone] Fax [phone]
Web Address: www.waynesvillenc.gov
Gary Caldwell, Mayor Robert W. Hites, Jr. Town Manager
Julia Freeman, Mayor Pro Tem Martha Bradley, Town Attorney
Jon Feichter, Councilmember
Anthony Sutton, Councilmember
Chuck Dickson, Councilmember

May 5, 2023

Daniel Boss, Assistant Regional Supervisor
North Carolina Department of Environmental Quality
Division of Water Resources, Water Quality Regional Operations Section
2090 U.S. Highway 70
Swannanoa, North Carolina 28778

RE: Notice of Violation & Intent to Assess Civil Penalty
Tracking Number: NOV-2023-PC-0150
Permit No. NC0025321
Town of Waynesville
Haywood County

Dear Mr. Boss:

The Town of Waynesville is in receipt of your letter dated April 28, 2023, reference a
recent Compliance Evaluation Inspection of the Waynesville WWTP which took place
on April 10, 2023. As required by the letter the Town of Waynesville offers the following
responses and support information for items of deficiency noted at the plant.

As you are aware a major upgrade of the Town of Waynesville WWTP is under
construction. This $28,440,000 project represents a major undertaking and financial
commitment on behalf of the Town of Waynesville and the citizens and customers of the
system. The Town of Waynesville entered into a Special Order by Consent (SOC) with
the Environmental Management Commission and the Division of Water Resources
dated December 31, 2020, to enable the Town to move forward with the project. The
SOC provided slightly relaxed effluent limits to enable the WWTP to operate in
compliance during the construction of this major upgrade.

Your letter of April 28, 2023, and the Notice of Violation & Intent to Assess Civil
Penalty came as a surprise to the Town as all of the seven items listed in your letter as
components of a potential Civil Penalty are being addressed by the upgrades being
made as a part of the construction project. Approved plans and specifications for the
project are in place and an Authorization to Construct has been issued.

I offer the following explanation for each of the seven items and trust that the good
efforts of the Town moving forward with the upgrade and the expenditure of more than
$28 million dollars for the project as adequate justification to strongly consider that there
16 South Main Street · P.O. Box 100 · Waynesville, NC 28786 Phone [phone] Fax [phone]
Web Address: www.waynesvillenc.gov
is no need to assess an additional civil penalty upon the Town of Waynesville.

The seven items are as follows:

Flow Measurement- Influent

The 24” Palmer- Bowlus flume used for flow measurement has been in place for many
years and was previously permitted. The flume can accurately measure flows up to and
above 6.0 MGD. An ultrasonic flow meter is in place to record flows from the meter.
Only when influent flow depths in the influent sewer pipe exceed approximately 27-
inches does the flow meter flume get surcharged and at that point flow meter accuracy
is diminished. This is at flows greater than about 6.50 MGD. Note that this condition
occurs infrequently and only after high rainfall events.

The construction project will replace the flow meter with a new flow meter designed to
measure peak flows in excess of 12.0 MGD and includes new sections of influent sewer
line to the new plant headworks.

Primary Clarifier

The two primary clarifiers have been in place for more than 30 years. The scum removal
arm and removal beach have been repaired numerous times over the life of this
equipment. Scum which is removed by the equipment is pumped to either the sludge
thickeners or headworks from the scum pits as Mr. Evans described during the
Compliance Inspection. As noted, the two primary clarifiers are being replaced by a
new primary treatment facility as a part of the plant upgrades and will be abandoned
once the new facility is online.

In the meantime, and during the construction period plant staff will continue to pump out
and properly dispose of any scum removed by the equipment.

Scum which is not collected and removed by the equipment flows to the intermediate
pump station where it is pumped to the aeration basins where much of this scum is
broken down by the biological process.

Secondary Clarifiers

The two secondary clarifiers, like the primary clarifiers, are more than 30 years old and
were designed based upon acceptable design guidelines at the time they were installed.
This included an 8-foot side water depth which isn’t optimal for solids removal from the
activated sludge process, especially when high mixed liquor concentrations (MLSS) are
run in the aeration process.

Each clarifier is equipped with a Clari-vac sludge removal system which has never
operated at a very high-performance level. Thus, allowing solids to flow out of the
clarifier at higher flow rates. The Clari-vac sludge removal system also has no means to
16 South Main Street · P.O. Box 100 · Waynesville, NC 28786 Phone [phone] Fax [phone]
Web Address: www.waynesvillenc.gov
capture and remove scum from the surface of the clarifier.

Any modifications to the existing Clari-vac sludge removal system would be expensive
and most likely not very effective.

As noted in the Compliance Inspection the two secondary clarifiers are being modified
and retrofit as a part of the construction project. Improvements include raising the side
walls to increase side water depth and improve settling. The clarifiers will have new
scraper type sludge removal equipment, new effluent weirs with scum baffles and a
scum removal system. These improvements will greatly enhance the performance of the
secondary clarifiers and allow the plant to perform within limits.

Disinfection – Gas

The Compliance Inspection noted the presence of solids in the chlorine contact
chamber. Plant staff typically clean out each side of the chlorine contact basin at least
every 2 to 4 weeks to remove solids. These solids are disposed of at the head of the
plant. Staff will continue to clean the basins until the construction upgrades are
completed.

Improvements include a wall and new weir to raise the water level in the chlorine
contact chamber to increase hydraulic detention times and to allow more options for
plant staff to remove any accumulated solids. Improvements being made to the
secondary clarifiers will reduce the amount of solids which may collect and settle in the
chlorine contact chamber once the upgrades are completed.

Effluent Sampling

The plant has not had effluent flow metering for a number of years and the old flow
measurement equipment which was in place has long since been removed and was
outdated. The chlorine contact chamber is divided into two sections, each section has a
broad crest weir at which point effluent exits the basin to the discharge pipe.

As a part of the plant upgrade a new flow meter will be provided for each weir to
measure and totalize effluent flow. Once this flow meter is in place it can be utilized to
convert the effluent sampler to flow paced are requested.

Aerobic Digester

As noted, the current sludge holding tank is not aerated. The sludge holding tank was
an original anaerobic digester and the mixing and heating system were at the end of
their service life. In addition, the steel floating tank cover was deteriorated and in bad
condition. For safety concerns and the presence of methane gas from the anaerobic
conditions in the digester the decision was made to remove the floating cover and the
gas collection and reuse system.

16 South Main Street · P.O. Box 100 · Waynesville, NC 28786 Phone [phone] Fax [phone]
Web Address: www.waynesvillenc.gov
Plant improvements associated with the upgrade include the addition of an aeration
system for the sludge holding tank.

The current sludge management plan for the plant is to dewater sludge on the belt filter
press with dewatered sludge hauled to the Haywood County, White Oak landfill for final
disposal. Even without the presence of aeration in the sludge holding tank the sludge
from the plant dewaters to an acceptable percent solid required by the White Oak
landfill. Currently there is no need or driving force to ensure adequate digestion of the
sludge to meet a Class B standard under the 503 regulations.

As the construction project continues to move forward the Town will continue to
evaluate the sludge management options including upgrades to the sludge
holding/digester tank as needed.

Standby Power

As noted, the existing standby power generator does not have adequate capacity to run
all components of the plant in the event of a power outage. The key components
requiring power under the current plant configuration are the bar screen at the
headworks, intermediate pump station, one aeration blower, secondary clarifier sludge
removal equipment, return sludge pumps, plant water system for chlorination and an
outlet in the lab for the BOD incubator. Plant staff will continue to evaluate the existing
generator and make wiring modifications where possible to allow the generator to power
as many of these systems as possible.

The plant upgrades include two new 600 kW generators which will power all of the
necessary treatment plant components in the event of a power outage.

The Town is working in good faith with DWR to continue operation of the WWTP under
the provisions of the NPDES permit, the approved construction documents and in
concert with the approved Special Order by Consent. The SOC and approved
construction plans have identified each mechanical/facility concern you have noted in
the NOV. The Town does not believe it is reasonable or justified to note issues that
have already been identified and that have an established solution path to full
restoration of the plant. The SOC recognizes this and the Town and DWR entered into
this consent agreement to address these issues. At this point, the Town will do
everything possible to provide appropriate management and operation of the facilities in
place. We hope DWR will be consistent with the current agreement and note that the
deficiencies identified are being addressed in a comprehensive way.

Please consider the information provided above as support documentation as to the
positive actions of the Town of Waynesville to continue operation and maintenance of
the WWTP to remain in compliance with the NPDES permit, the expenditure of more
than $28 million for the plant upgrades under way and other efforts by the town to
address issues in the collection system and to reduce inflow and infiltration (I/I). We
trust this information is sufficient to not issue a civil penalty at this time based. If you
16 South Main Street · P.O. Box 100 · Waynesville, NC 28786 Phone [phone] Fax [phone]
Web Address: www.waynesvillenc.gov
have any questions, please do not hesitate to contact me at [e-mail]
or 828-452-2491. Thank you for your consideration.

Sincerely,
Town of Waynesville

Robert W. Hites Jr.
Town Manager

CC: Landon Davidson – Asheville regional office -DWR
Jeff Stines – Town of Waynesville
Jeff Evans – Town of Waynesville
Keith Webb – McGill Associates