NC0026641_Hearing_Officer_report-final_20190425-TCF-LC_20190425

ROY COOPER
Governor
MICHAELS.REGAN
Secretary
LINDA CULPEPPER
Director
MEMORANDUM
NORTH CAROLINA
Environmental Quality
April 25, 2019
TO: Linda Culpepper, Director
Division of Water Resources
FROM: Tom Fransen, Chief, Water Planning Section
Division of Water Resources
r1r
i NV
SUBJECT: Hearing Officer's Report and Recommendations
Town of Siler City, NPDES Wastewater Permit No. NCO026441
Siler City WWTP, Chatham County
On January 24, 2019, I served as Hearing Officer for a public hearing at the Siler City Town Hall
Courtroom in Siler City, North Carolina. The purpose of the hearing was to gather public
comments regarding the Divisions proposal to reopen and modify the NPDES permit for the
Siler City WWTP.
Public notice of the draft permit (Attachment A) was originally published in 77w Chatham News
on October 25, 2018 and posted on the DWR website. In response to several requests, the
Division agreed to hold a public hearing. Public notice of the hearing (Attachment B) was
published in Tlu Chatham News + Record on December 20, 2018 and posted on the DEQ website
at httos: / / deci.nc.izov/news/events/public-hearing-siler-city-wwtp-permit-nc002644. The
hearing was then held, and oral and written comments were received. The comment period
ended on January 31, 2019. Due to the federal shutdown in January, we accepted comments
from the U.S. Fish & Wildlife Service on February 7.
I have considered all comments received and worked with the Division staff to identify a course
of action. This report presents my findings and recommendations for the subject NPDES
wastewater permit, NC0026441. Revised copies of the permit and fact sheet are provided as
Attachments C and D and highlight changes from the original draft versions.
The report has been prepared using the following outline:
I. Background
II. Public Hearing
III. Comments Received/ Response to Comments
IV. Summary and Discussion
V. Recommended Actions
Attachments
North Carolina Department of Environmental Quality I Division of Water Resources
QUA 512 North Salisbury Street 11617 Mail Service Center I Raleigh, North Carolina 27699-1617
•—:x D �, PP 919.707.9000

Hearing Officer's Report: NPDES Permit NCO026441
Town of Siler City, Siler City W WTP
I. Background
Facility and Permit. The Town of Siler City owns and operates the Siler City W WTP, a 4.0 MGD
activated sludge treatment plant. The plant discharges treated wastewaters to Loves Creek, 0.4
mile upstream of its confluence with the Rocky River.
The discharge is subject to, among other things, limits for biochemical oxygen demand (BODs),
total suspended solids (TSS), ammonia nitrogen (NIs-N), and total phosphorus (TP) (Table 1).
The Town has complied with these limits (2012-2018) with a few minor exceptions. The plant
has bypassed its final filters multiple times due to storm events and inflow and infiltration (I/I)
into its collection system, but it has still met the limits.
Table 1. Existing Effluent Limitations (Partial List)
PARAMETER
EFFLUENT LIMITATIONS
Monthly Average
Weekly Average
BODs
(April 1- Oct 31)
5.0 mg/L 10.0
(Nov 1— March 31)
mg/L
7.5 mg/L 15.0 mg/L
TSS
30.0 mg/L
45.0 mg/L
NH3 as N
(April 1- Oct 31)
1.0 mg/L 2.0 mg/L
3.0 mg/L 6.0 mg/L
(Nov 1— March 31)
Total Phosphorus
(April 1— Sept 30)*
0.5 mg/L (quarterly average) 2.0 mg/L
(Oct 1— March 31)*
(quarterly average)
Total Nitrogen
i
Monitor Only
*Seasonal timeframes were modified to accommodate quarterly limits.
The current treatment plant, constructed in 1998, was designed to treat a combination of
municipal and industrial wastewaters. However, because it was not subject to total nitrogen
(TN, or nitrogen) limits, the plant was not designed to remove nitrogen.
Past Industrial Users, Water Quality Impacts. Until 2011, the plant received high -strength
wastewaters from two poultry processing facilities, Pilgrim's Pride and Townsend Poultry. The
Towns discharge averaged 31.5 mg/L TN, or 6671b/day, from 2004-2008, when both poultry
facilities were operating. The discharge raised nitrogen concentrations in downstream waters
significantly. Loves Creek and the Rocky River experienced excessive growth of aquatic plants
and filamentous algae, and Woody's Dam Lake (Reaves Lake) is listed on the 303(d) list as
impaired due to chlorophyll -a exceedances.
Pilgrim's Pride closed its facility May 2008, and Townsend Poultry closed in October 2011, and
the Towns discharge decreased to 14 mg/L TN, or 2001b/day (2016-2017). The degree of
improvement in water quality has not been determined, but residents of the area indicate that
the streams have visibly improved.
A 2011 DWR report recommended that total nitrogen limits representing best available
technology be added to the permit at its 2011 renewal. However, both poultry processors had
already closed, and neither was expected to reopen in the foreseeable future. Without the
industrial inputs, effluent TN concentrations from the W WTP declined significantly. Rather
than add TN limits to the Towns permit - and prompt costly plant upgrades that might prove
unnecessary later - the Division added a reopener condition that allowed it to reopen the
permit to add nutrient limits later if necessary.
New Industrial User. In May 2016, Siler City announced that Mountaire Farms Inc. would
operate a new poultry processing facility at the former Townsend Poultry site. Per the reopener
provision in its permit, the Town notified the Division on December 9, 2016, that it intended to
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Hearing Officer's Report: NPDES Permit NCO026441
Town of Siler City, Siler City W WTP
accept wastewater from the industry beginning in early 2019. The Division then notified the
Town by letter on June 8, 2017, that it planned to reopen the permit to address the expected
increase of nitrogen in its discharge.
Per its permit, the Town conducted a treatability analysis to evaluate the impact of Mountaire
Farms' initial production levels (Phase 1, 0.75 MGD) on the Towns discharge. It later conducted
a second analysis to examine the impacts at full production (Phase 2,1.25 MGD). The studies
estimated that, with the addition of Mountaire Farms' wastewaters, the Towns nitrogen
discharge will likely return to previous (2004-2008) levels or greater: 30 mg/L TN, or 640 lb/day
in Phase 1 and 38 mg/L TN, or 9901b/day at full Phase 2 production.
The projected increase in nitrogen is expected to impact the receiving waters to a greater degree
than previous poultry operations did unless significant controls are implemented first. Thus,
there is a compelling need to limit Siler City's nitrogen discharge and protect water quality in
Loves Creek and downstream waters. The Town has proposed to upgrade its plant to reduce its
nitrogen discharge to current levels, and it has secured tentative funding for $5.75 million for
the project.
Proposed Permit Modification. In October 2016, the Division published notice of its intent to
reopen the permit to establish the following nitrogen control requirements:
• A technology -based Total Nitrogen (TN) limit of 73,058 lb/yr (equivalent to 6.0 mg/L TN at
4.0 MGD, or 200 lb/day), to become effective January 1, 2023;
• Two new conditions requiring the Town to (1) evaluate the potential to reduce its TN
discharge through optimization of the existing plant and (2) implement effective measures
within 22 months of permit issuance, while plant upgrades are still underway; and
• A new condition specifying how annual mass TN loads are to be calculated and reported.
The draft permit would ensure that, within four years, the Town will sufficiently upgrade its
treatment processes to hold nitrogen discharges to current levels. It also aims to identify and
implement operational improvements ("optimization') while the upgrades are designed and
constructed.
II. Public Hearing
Public notice of the draft permit was originally published in The Chatham NeWS on October 25,
2018 (Attachment A) and posted on the DWQ website. In response to multiple requests
received, the Division agreed to hold a public hearing. Public notice of the hearing (Attachment
B) was published in The Chatham News + Record on December 20, 2018 and posted on the DEQ
website at https• / /deq nc g_ov/news/events/1ublic-hearing-siler-city-wwtp-permit-nc002644.
The public hearing was held on January 24, 2019, at 6:00 p.m., at the Siler City Town Hall
Courtroom in Siler City. The purpose of the hearing was to gather comments regarding the
proposed reopening and modification of the NPDES permit for the Towns W WTP. Oral and
written comments were received at the hearing, and additional written comments were
received during the comment period. The comment period ended on January 31, 2019, except
that comments from U.S. Fish & Wildlife Service staff were accepted on February 7, in light of
the federal government's partial shutdown in January.
Approximately 54 people attended the public hearing including 38 members of the general
public; five Town employees or consultants; ten staff members of DWR's Central Office
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Hearing Officer's Report: NPDES Permit NC0026441
Town of Siler City, Siler City W WTP
(Raleigh), the Raleigh Regional Office, and DEQ's Public Information Office; and the hearing
officer. The sign -in sheet for non- speakers is attached as Attachment E.
Nineteen individuals spoke at the hearing. The speakers' sign -in sheet is included as
Attachment F. Written comments received are available on the Divisions website at the link
provided in Attachment I. (Large attachments of supporting materials are not included but are
available upon request.)
As hearing officer, I provided opening and closing comments (Attachment G). Mike Templeton
provided an overview of DWR's draft NPDES permit (Attachment H), and comments were then
heard.
III. Comments Received/ Response to Comments
Division staff have reviewed all comments received. This section summarizes the key comments
and responses to those comments.
A. Impacts of the Town's Discharge on Water Quality and Natural Resources
Comments:
• The Rocky River is a significant and valuable resource and recreation area, and it should
be protected.
• Nitrogen discharges from the Pilgrims Pride and Townsend Poultry resulted in thick,
slimy, noxious algal growth and dead zones in downstream waters, especially in the
Rocky River.
• The proposed discharge will release even more total nitrogen (TN) into Loves Creek and
the Rocky River.
• The proposed discharge will not protect existing uses - fishing, swimming, aquatic life,
drinking water supply - in the creek and downstream waters.
• Several aquatic species found in downstream waters are considered rare, threatened, or
endangered according to state or federal listings and the NC Wildlife Action Plan; for
example, the Cape Fear Shiner and Mimic Shiner (finfish) and the Brook Floater and
Savannah Lilliput (freshwater mussels). Efforts are underway to aid their recovery.
Reduced water quality in the streams could hamper this and other restoration efforts.
• The recent removal of Woody's Dam has improved habitat in the vicinity and
reconnected populations of rare and endangered mussels.
• The shiners seem to tolerate the growth of filamentous algae, but sedentary species are
more susceptible to impacts.
Response: The Division recognizes that the Siler City W WTP will discharge significantly
more nitrogen due to the wastes from the new Mountaire Farms facility. History shows that
the added nitrogen will impact Loves Creek, Rocky River, and downstream waters. It may
also pose some threat to aquatic life in those streams, including rare, threatened, or
endangered species.
It is the Divisions intent to address these issues as quickly as possible.
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Hearing Officer's Report: NPDES Permit NC0026441
Town of Siler City, Siler City W WTP
B. Necessary Steps to Protect Water Quality and Natural Resources
Comment: The Clean Water Act (CWA) and Endangered Species Act (ESA) require DWR to
protect designated uses in these streams.
Response: The Division intends to comply with both state and federal requirements and
believes that, in the absence of a TMDL, the proposed approach best meets the intent of the
Acts.
Comments:
The proposed discharge violates the CWA: the streams are listed on the 303(d) list as
"impaired", and a TMDL or water quality study is required as soon as possible to
determine protective water quality -based limits.
The nitrogen discharge should be regulated to limit its impacts and protect water quality
in Loves Creek and the Rocky River.
The proposed limits are technology -based, not water quality -based as required for a
discharge to impaired waters.
Response:
The Division does not yet have a basis for setting water quality -based effluent limits
(WQBELs) for Siler City or other dischargers in the watershed. Either a Total Maximum
Daily Load (TMDL) or nutrient criteria for the affected waters must be established to set
protective WQBELs. Neither process can be completed quickly.
TMDL: It will likely take 5-8 years to complete a TMDL or water quality management
study for the watershed and 1-3 years more to adopt implementing rules. Typically,
point sources are allowed five years to complete the necessary upgrades and comply
with any new limits.
o Protective? Yes. Total time required:11-16 years.
• Nutrient Criteria: It will take 1-2 years for the NCDP SAC to develop nutrient criteria
for the affected waters plus 1-3 years for rulemaking and five for implementation.
o Protective? Yes. Total time required: 7-10 years.
(The Division initiated a two-year surface water monitoring effort in January 2019 to
collect data that will support either effort.)
Instead, the Division proposes to establish a technology -based effluent limitation (TBEL) for
nitrogen. The limit is equivalent to the Towns 2016-2017, "no -poultry" loads,
approximately 200 lb/day. It will take an estimated four years (now 31/2 years) for the Town
to upgrade its treatment plant to meet the proposed limit.
o Protective? To be determined. Total time required: 31/2 years to implement.
At the same time, the Town must evaluate operational approaches ("optimization') to
reducing its nitrogen discharge. The effectiveness of this approach at Siler City has yet to be
determined. Similar efforts at municipal treatment plants around the country have achieved
significant reductions, but good results are not guaranteed.
o Protective? To be determined. Total time required: 11/2-2 years to implement.
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Hearing Officer's Report: NPDES Permit NC0026441
Town of Siler City, Siler City W WTP
It appears that the combination of a establishing a nitrogen limit and requiring optimization
is the most expeditious way to achieve real nitrogen reductions in Siler City's discharge and
address water quality issues in Loves Creek and the Rocky River.
Comments:
• The Town's treatment plant upgrades should be completed more quickly than the four
years allowed.
• The nitrogen limit should be more stringent, and the Town should be required to
comply immediately.
Response: Four years (now 31/2 years) is not an unreasonable time to expect the Town to
complete the upgrades and comply with the limit. In that time, the Town must secure
funding, advertise for and retain a design engineer and contractor, create and submit its
design to DWR for approval and obtain of an Authorization to Construct permit, and
construct the approved upgrades at the plant without affecting its on -going operations.
The Towns limit is equivalent to 6.0 mg/L TN, which represents a basic nitrogen removal
process. The limit will ensure that the Towns nitrogen discharge does not exceed its current
levels once the upgrades are completed.
The risk in setting a more stringent limit now is that future studies may reveal that the limit
is not as stringent as the interim limit. Nitrogen removal is expensive, and the Town does
not have unlimited funding for plant improvements. If the interim limit is more stringent
than necessary, the Town will have spent more - perhaps much more - than was necessary.
Comment: The timeframe for optimizing plant operations should also be shortened.
Response: The current schedule is not overly generous. But the Town determined that the
time allowed for preparing its report could be reduced from six months to four months.
Comment: Optimization is not likely to be successful because of the Towns inflow and
infiltration problems and the resulting overflows and treatment bypasses. These issues
should be addressed.
Response: I/I may influence the effectiveness of optimization, but the effort may prove
effective nonetheless. Although it has bypassed its tertiary filters on several occasions due to
spike flows from storm events, the Town has not bypassed its main treatment units and has
complied with permit limits. Its monthly average TSS did not exceed 6.0 mg/L in that same
period.
The Town continues to restore its collection system in order to reduce inflow and infiltration
into the system and thereby reduce the need to bypass its filters.
C. Economic Considerations and Responsibilities
Comments:
Mountaire Farms should be responsible for managing its wastes and should reduce its
nitrogen loads to the Towns treatment plant.
Mountaire Farms should be required to pay the cost of treating its wastes.
Mountaire Farms has a poor environmental record elsewhere and should be subject to
protective limits here.
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Hearing Officer's Report: NPDES Permit NC0026441
Town of Siler City, Siler City W WTP
• Protecting water quality and the public health should be a higher priority than
Mountaire Farms' financial gain.
• New jobs and an economic boost are welcome, but only to a point. Good stewardship
now will reap economic benefits, too, as Chatham County is recognized for its natural
beauty and resources.
Response: It is the Towns responsibility to weigh these considerations and establish terms
for the industry's discharge to the Siler City W WTP. The Town had little warning of
Mountaire Farms' decision to build its new plant and little time to set those terms. Once the
nitrogen limit is added to its permit, the Town can consider whether to add additional
requirements in Mountaire Farms' industrial user permit.
Comment: Mountaire Farms should not be allowed to discharge until it or the Town have
installed the treatment necessary to protect water quality.
Response: Mountaire Farms' flows to the Town are regulated through an Industrial User
Permit issued by the Town. The IUP was issued in 2017 and authorized Mountaire Farms to
release pretreated wastewaters beginning in January 2018. (The facility began discharging in
January 2019.)
Under the state's pretreatment program, limits in a municipal NPDES permit are considered
in setting limits for industrial users. Because Siler City's NPDES permit does not yet contain
a total nitrogen (TN) limit, the Town has had no clear basis for limiting Mountaire Farms
nitrogen discharge.
Comment: Requirements for onsite pretreatment should be reconsidered.
Response: Installing additional treatment units at the Mountaire Farms facility to remove
nitrogen will be extremely expensive and, like the Towns upgrades, require several years to
complete.
D. Mitigation Opportunities
Comment: DWR, the Town, and Mountaire Farms should work to offset the new nutrient
loads. Potential project sites in the watershed have been identified (TetraTech, 2005) where
BMPs could be implemented to achieve reductions, and some of these measures may still be
actionable.
Response: Nonpoint source requirements fall outside the scope of the NPDES program and
so cannot readily be added to the Towns permit. However, the Division agrees that these
efforts could help offset the new loads. DWR staff will meet with local Soil and Water
Conservation staff and the Town to consider how these measures could be implemented.
Comment: Monitoring should be expanded to evaluate how effective the offsets, BMPs, or
other measures are.
Response: In January 2019, the Division initiated a two-year instream monitoring project in
the Deep River and Rocky River watersheds. Monitoring will continue at the existing
ambient and coalition stations in the watersheds and at three new stations each in the two
watersheds.

Hearing Officer's Report: NPDES Permit NC0026441
Town of Siler City, Siler City W WTP
The data collected will be used to support the development of a watershed model for the
upper Cape Fear watershed. The model will then be used to support NPDES permitting of
nutrients in the watersheds.
The project will not track the effectiveness of these BMPs specifically, but it will provide
information on conditions associated with algal bloom frequency and duration, which will
also be useful.
E. Other Comments
Comment: Replace chlorination with ultraviolet or ozone disinfection to protect sensitive
aquatic organisms.
Response: The Town can consider ultraviolet or ozone disinfection in the design of its plant
upgrades. The Division will consider the need for alternative means of disinfection in its
design review of the plant upgrades.
Comments:
• Set ammonia limits based on EPA's new criteria.
• Ammonia limits are probably protective.
Response:
• The state has not yet adopted EPA's new ammonia criteria so will continue to base limits
using the current working criteria, which are similar to the EPA's. The Division will
consider the new ammonia criteria in the next Triennial Review of water quality
standards (now underway) and will implement any new standards through the permit
once the standards are adopted into rule.
III. Summary and Discussion
The Siler City W WTP discharges treated wastewaters to Loves Creek, 0.4 mile upstream of its
confluence with the Rocky River. The plant is not subject to nitrogen limits and so is not
designed to remove nitrogen.
Mountaire Farms began initial operations in January 2109 and discharges to the Town's
collection system and treatment plant. It is not subject to nitrogen limits and so does not remove
nitrogen. It will substantially increase the nitrogen load to the Town and to the receiving waters
as production levels increase.
Two poultry processors discharged to the plant in the past, and downstream surface waters
were impacted significantly. Since the closure of the processors, those waters have begun to
recover. They will likely be impacted again and possibly to a greater degree when Mountaire
Farms begins production.
There is widespread agreement that this situation must be corrected as soon as possible so as to
minis -die the impacts to surface waters and to the aquatic species that inhabit them.
The Town has diligently pursued funding to upgrade its treatment plant for nitrogen removal
and has received tentative awards totaling $5.75 million It now has the opportunity to
undertake this project in order to restore water quality downstream of its discharge. However,
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Hearing Officer's Report: NPDES Permit NC0026441
Town of Siler City, Siler City W WTP
some of the funding is conditioned on the Town first demonstrating the need for the project.
The Town needs this permit and the proposed TN limit to demonstrate that need.
If the Town does not receive full funding for the project, not only will it have to postpone the
upgrades until it can obtain additional funding; it may also have to redirect funding meant for
other projects, such as collection system repairs undertaken to reduce inflow and infiltration
and to reduce the frequency of filter bypasses at the treatment plant.
Thus, the proposal to establish a nitrogen limit in the Towns permit appears to be the most
effective and timely way for the Town to limit its impacts on surface waters.
While the Towns discharge is a significant source of nitrogen in the watershed, other sources
also impact water quality. For example, even under current "no -poultry" conditions,
impoundments on the Rocky River both upstream and downstream of Loves Creek exhibit low
dissolved oxygen levels and signs of nutrient impacts. Turner Reservoir (upstream of Loves
Creek) and the Cape Fear River behind Buckhorn Dam (downstream) have both been added to
the state's 303(d) list for exceedance of the chlorophyll -a standard. Downstream, Woody's Dam
Lake (Reaves Lake) is also on the 303(d) list (the dam was removed is 2018).
The Town is sensitive to concerns about water quality in Loves Creek and the Rocky River. It
has adopted ordinances to promote responsible development, proper stormwater management,
preservation of sensitive environmental areas, and restoration of natural resources within its
jurisdiction. And it is actively working with others on several water quality improvement
projects:
• Loves Creek Watershed Stewards - Stormwater management improvements and
riparian buffer restoration at Boling Lane Park. The Town has provided staff and
materials for buffer restoration, removal of invasive plant species, trail maintenance,
public education.
• 205J Stormwater Infrastructure Assessment and Mapping - Town will repair clogged or
damaged stormwater infrastructure that may contribute to flooding
• Park Shopping Center restoration
• EEG Floodplain Park
• Brownfields projects - Phase I and II Environmental Site Assessments on former
industrial sites (also part of EEG floodplain project)
• Septic Repair Grant (205J funds) - Rocky River watershed, Liberty to Goldston
• Loves Creek signs and stream naming contest
• CAM Site Readiness Spring Litter Sweep
• Pedestrian Master Plan - implementing pedestrian projects to reduce motor vehicle
miles
The Town has also hired a full-time grants administrator to manage the many varied funding
sources and opportunities for its various projects.

Hearing Officer's Report: NPDES Permit NC0026441
Town of Siler City, Siler City W WTP
IV. Recommended Actions
I recommend that the Division issue the proposed modification of the Siler City permit
NC0026441 as soon as possible and as follows:
The permit should include the total nitrogen limit and the January 1, 2023, compliance
date as originally proposed. This leaves the Town slightly more than 31/2 years to
complete its treatment plant upgrades.
The milestones for the optimization study should be extended by four months to allow
for the delay in permit issuance. The overall schedule should be shortened to 20 months
by reducing the time for report preparation from six months to four months.
Markup copies of the revised permit and fact sheet are included as Attachments C and D,
respectively. The recommended changes in each are shown in underline/ strikethrough format.
I also encourage the Division to:
• Meet with the Chatham County Soil and Water Conservation staff and the Town to
consider how to promote projects that would reduce nutrient contributions from farms
and other sites in the watershed.
• Continue the surface water monitoring project begun in January 2019 and use the results
in developing a watershed model for the Rocky River.
• Assist the Town in updating its Headworks Analysis for nitrogen if an update is
warranted following completion of the treatment plant upgrades.
• Continue to support the Town in its efforts to reduce I/I flows into its collection and
treatment systems.
• Continue to support the Town in its water quality protection efforts.
• Support resolution of the low dissolved oxygen problem at the Hackney Millpond, as
appropriate.

Attachments
A. Public Notice of Draft Permit
B. Public Notice of Hearing
C. Permit NC0026441, with Recommended Revisions
D. Permit Fact Sheet, with Revisions
E. Non -Speakers' Sign -In Sheet
F. Hearing Officer Presentation
G. NPDES Staff Presentation
H. Speakers' Sign -In Sheet
I. Public Comments (available in electronical form)