HomeMy WebLinkAboutNC0026123_Report_20230821ROY COOPER
Governor
ELIZABETH S. BISER
Secretary
RICHARD E. ROGERS, JR.
Director
NORTH CAROLINA
Environmental Quality
August 17, 2023
MEMORANDUM
To: Richard E. Rogers
Director, Division of Water Resources
From: Ramesh Ravella, Supervisor, Animal Feeding Operations Branch
Water Quality Permitting Section, Division of Water Resources
Subject: Hearing Officer's Report and Recommendations
City of Asheboro — Asheboro Wastewater Treatment Plant
NPDES Permit Number NCO026123
Randolph County
A Public Hearing was held on May 23, 2023, at the Corporate Training Center at the Randolph
Community College, 413 Industrial Park Avenue, Asheboro, NC 27205. The public hearing was
held under the authority of 15A NCAC 02H .0111. The purpose of this public hearing was to
receive comments on the Division of Water Resources' (DWR) draft National Pollutant Discharge
Elimination System (NPDES) permit renewal for the City of Asheboro's Wastewater Treatment
Plant (WWTP). The current permit is expired but administratively extended until a permitting
decision is made on the renewal.
In addition to listening to oral comments at the public hearing, DWR staff and the Hearing Officer
reviewed all written comments received through the end of the comment period. Following the
closing of the comment period, DWR staff worked with the hearing officer to consider and
deliberate over the comments and then to develop the recommendations presented in this
report. In preparation of this report, the hearing officer considered all public comments, the
public record, discussions with DWR staff related to the rules, and their review of the application
for the permit renewal.
The report has been prepared using the following outline:
I. History/ Background
II. Public Hearing Summary
III. General Comments
IV. Recommendations
V. Summary
VI. Appendices
I. History / Background
On March 21, 2016, the City of Asheboro (hereafter City) applied for an NPDES permit renewal
for its Asheboro WWTP (Appendix A). Upon technical review of the application and supporting
materials, DWR prepared an initial draft permit, which, pursuant to 15A NCAC 02H .0109(2), was
submitted for public comment on May 9, 2018 (Appendix B). The initial draft permit included
modifications to discharge limits, monitoring requirements for existing water quality parameters,
and the addition of limitations and monitoring requirements for the chemical 1,4-Dioxane based
on the facility's discharge into a Class C waterbody, Hasketts Creek. In NCDWR 2016: 1,4-Dioxane
in the Cape Fear River Basin of North Carolina: An Initial Screening and Source Identification Study,
DWR had found concentrations of 1,4-dioxane amongst the highest observed at Study Site
NCSU24 in Hasketts Creek, just downstream of the Asheboro WWTP discharge.
During the public comment period, comments were received from multiple municipalities
requesting further consideration of 1,4-dioxane limits for the protection of downstream water
supply water uses. Per Environmental Protection Agency's (EPA) November 2017 Technical Fact
Sheet-1,4-Dioxane, 1,4-dioxane is completely miscible in water and resistant to biodegradation.
As such, the mass loading of the chemical identified in the facility's discharge is expected to
persist downstream to the nearest drinking water intake. Multiple drinking water utilities exist
downstream of the Asheboro WWTP's discharge, and as such, protection of the downstream
water supply uses needs to be considered. Allowable discharge concentrations were calculated
for both the direct discharge to Class C Hasketts Creek and for the nearest downstream water
supply (WS-V) boundary, and the more restrictive concentration was selected for protection of
downstream uses. The nearest downstream water supply (WS-V) boundary is located in the Deep
River, 1.0 mile upstream of Tysons Creek and 43.5 miles downstream of the Asheboro WWTP
discharge. The water supply boundary is for the Deep River (Gulf-Goldston) water supply
watershed. Each allowable discharge concentration was calculated considering the applicable
receiving stream's Average Annual Flow (AAF), appropriate Instream Target Value (ITV) and the
facility's permitted design flow.
For the direct discharge to Class C Hasketts Creek, an ITV of 80 µg/L for non -water supply waters
at an AAF of 12 cfs and a permitted design flow of 9.0 MGD (13.95 cfs) was considered. This
calculation yielded a chronic allowable discharge concentration of 149 µg/L. When considering
the downstream WS-V waters, a 1x10-6 risk level ITV of 0.35 µg/L for water supply waters at an
AAF of 846 cfs (calculation estimated by USGS for WS-V boundary of Gulf-Goldston WS
watershed) and a permitted design flow of 9.0 MGD (13.95 cfs) was considered. This calculation
yielded a chronic allowable concentration of 21.58 µg/L. The discharge determination based on
direct discharge to Class C Hasketts Creek is insufficiently protective of downstream water supply
uses. As such, the chronic allowable discharge concentration of 21.58 µg/L has been used in
determination of permitting actions.
Based on a review of the effluent data, the Asheboro WWTP demonstrates a reasonable potential
to exceed the allowable discharge concentration, resulting in a limit being incorporated into the
draft permit. Recognizing that 1,4-Dioxane is an emerging contaminant and industrial users are
in the process of adjusting to its impact and use in materials, a phased implementation
compliance schedule has been included in the permit. In Asheboro WWTP's case, the future
phase 1,4-Dioxane target must not cause violation of the ITV for 1,4-Dioxane at the water supply
boundary.
Page 2 of 13
Considering the existing effluent concentrations experienced at the facility, the first phased limit
was calculated to be the 50th percentile value of the effluent data submitted from January 2018
through September 2022, which was 55.7 µg/L. This initial phased limit was calculated after
removing detection values identified as outliers (Z score > 3 or < -3). The second phase is set at
the EPA Drinking Water Health Advisory of 35 µg/L for 1,4-dioxane. The third and final phased
limitation set the allowable discharge concentration based on the ITV for 1,4-Dioxane calculated
at the water supply boundary which came out to 21.58 µg/L. Daily maximum limitations have
been calculated for each phase from the chronic monthly average limitations using EPA guidance.
Derivation of the maximum daily limit is based on EPA's Technical Support Document (TSD)
recommendations.
According to the TSD, developing final permit limits for pollutants affecting human health is
somewhat different from setting limits for other pollutants because the exposure period is
generally longer than 1 month. Therefore, the EPA -recommended approach for setting water
quality -based limits for human health protection with statistical procedures is as follows:
•Set the Average Monthly Limit (AML) equal to the Wasteload Allocation (to meet the
instream target value of 0.35 µg/L)
• Calculate the Maximum Daily Limit (MDL) based on effluent variability and the number of
samples per month using the multipliers provided in TSD Table 5-3.
This approach ensures that the instream criteria will be met over the long-term and
provides a defensible method for calculating an MDL.
The daily maximum final limit was developed using the recommended approach in TSD Section
5.4.4, for human health protection. Input variables for the multiplier table consulted (TSD Table
5-3) included:
• A coefficient of variation (CV) of 0.8 based on the most recent 58 data points (July 2021—
September 2022) and after removing Z-score-identified outlier values,
• AML exceedance probability of 95th percentile,
• MDL exceedance probability of 99th percentile,
• A weekly sampling frequency (n = 4/month).
The table yielded a multiplier of 2.29, which was applied to the average monthly limits of 55.7
µg/L, 35.0 µg/L, and 21.58 µg/L to obtain the maximum daily limits of 127.6 µg/L, 80.2 µg/L, and
49.4 µg/L, respectively.
Based on this consideration of downstream drinking water uses, a second draft permit was
prepared to incorporate the revised 1,4-dioxane requirements. In addition to the 1,4-dioxane
requirements, the following changes were proposed:
• Reduced BOD, Ammonia, TSS and fecal coliform monitoring
• Removal of total mercury limits
• Removal of total chromium limits
• Removal of total zinc monitoring
• Revised Ammonia limits
Page 3 of 13
• Total Selenium monitoring
• Bromodichloromethane limit
• Total silver limits and compliance schedule
• Quarterly PFAS monitoring (with 6-month delay after EPA -approved method is published)
To accompany the revised draft permit, DWR prepared a Fact Sheet (Appendix D) to explain
permit conditions and proposed changes to permit conditions in accordance with 15A NCAC 02H
.0108.
Pursuant to 15A NCAC 02H .0109(2), DWR provided a public notice of the proposed action to
issue the permit and accepted public comment on the draft permit from December 6, 2022, until
January 27, 2023. A total of six comment sets were received during this period and two of those
comments requested a public hearing. All comments can be found in Appendix E.
Based on public input, and in accordance with General Statute 143-215.1(c)(3), the Director of
DWR determined that a public hearing was warranted. In accordance with 15A NCAC 02H
.0109(b), notice of the public hearing was published in The Courier -Tribune (newspaper with
circulation in Randolph County) on April 20, 2023 (Appendix F). This notice was transmitted
electronically via DWR's e-mail listsery and posted to DWR's Website.1 In addition, DWR issued a
press release to provide information about the scheduled public hearing and sent copies of the
press release via e-mailed to requestors. The public hearing was held on May 23, 2023, as
described below. After the hearing, the public comment period remained open until 5 p.m. on
May 24, 2023.
II. Public Hearing
A public hearing was held on May 23, 2023, at the Corporate Training Center at the Randolph
Community College, 413 Industrial Park Avenue, Asheboro, NC 27205. The purpose of the hearing
was for DWR to receive public comments and additional information relevant to the Asheboro
WWTP draft NPDES permit and DWR's NPDES permit renewal decision for the City of Asheboro
— Asheboro WWTP.
Seventeen people attended the public hearing (Appendix G), including nine stakeholders and
eight staff members from the Department of Environmental Quality. Attendees and speakers
included representatives of Southern Environmental Law Center (SELC), Haw River Assembly
(HRA), Fayetteville Public Works Commission (PWC), the City of Asheboro, the City of
Greensboro, Cranfill Sumner, LLP, Brooks Pierce Law Firm, and Piedmont Triad Regional Water
Authority. The hearing officer provided opening remarks and Nick Coco of DWR presented
background information on the NPDES permitting process and the proposed draft permit. Three
individuals registered in advance of the hearing to provide oral comments. Speakers were given
six minutes each for oral remarks. Of the three individuals who spoke, all expressed concerns
about the permit as drafted or had specific requests regarding the draft permit. The list of
attendees including speakers is in Appendix G. A link to the public hearing recording is attached
to this report (Appendix H).
' https://www.deq.nc.gov/news/events/notice-intent-issue-npdes-wastewater-permit-nc0026123-0
Page 4 of 13
DWR received six written comments during the second public comment period, including two
comments after the public hearing (Appendices I and J). All of these comments expressed
concerns with the permit as drafted and some comments made specific requests. A summary of
the oral and written comments, along with responses that have a direct impact on the permit
decision making process, are included below in Section III.
III. Public Comments and Division Responses
The following is a summary of the comments received during the May 23, 2023 public hearing
and during the public comment period. Comments were received from the following entities:
• Cranfill Sumner, LLP on behalf of the City of Reidsville,
• The City of Asheboro,
• Cape Fear Public Utility Authority (CFPUA),
• Fayetteville Public Works Commission (PWC),
• Brooks Pierce on behalf of the Cities of Greensboro and Asheboro, and
• Southern Environmental Law Center
The discussion below organizes and summarizes the public comments received by topic and
provides the Division's response. Both the written and oral comments were included in this
section. All comments received for both comment periods are included in Appendix K.
Ammonia Comments
Comment: Site -Specific Ammonia Limits
One commenter requested site -specific ammonia limitations be calculated to see if a different
result is generated.
Response: Site -specific ammonia calculations have been conducted per Permittee request and
have been found to be consistent with the conclusions applied to the draft permit. As such, no
changes have been proposed from the draft ammonia requirements.
Silver Comments
Comment: Silver Water Effect -Ratio
One commenter requested clarification on the effects of performing a total silver Water -Effect
Ratio (WER) study, expressing concern that the language states that after completion of the WER
and implementation of the multiplier, the compliance schedule is removed. What happens if the
WER does not account for enough of a multiplier to result in immediate compliance? The City
needs additional time to assess how to proceed if that were the case.
Response: As the incorporation of the results of the WER study into the NPDES permit would
require a major modification, the Division may include the continuation of the compliance
schedule to provide time for the City to achieve compliance with the new limits during that process
if necessary.
PFAS Comments
Page 5 of 13
Comment: PFAS Monitoring
Multiple commenters stated that the proposed quarterly monitoring of PFAS is insufficient and
recommended weekly monitoring, with one commenter recommending the addition of weekly
instream PFAS monitoring as well. One commenter stated that the proposed quarterly
monitoring was too much of a financial burden and requested reduction from quarterly to 2/year
PFAS monitoring after the first 2 years of monitoring.
Response: The Division considers quarterly monitoring for PFAS to be adequate based on
guidelines in the EPA Memo addressing PFAS discharges in NPDES permits (dated 12/5/2022)2
and concentrations of PFAS chemicals detected from influent waste stream samplings in 2019.
Comment: PFAS Limits
Two commenters recommended that limits for PFAS chemicals be added to the permit.
Response: A PFAS monitoring requirement has been added to the NPDES permit. After EPA
publishes a 40 CFR Part 136 method for PFAS testing in wastewater, the proposed permit
condition will require PFAS monitoring to begin six months later. This six-month period provides
time for laboratories to become certified using the new EPA -approved method. See DEQ's PFAS
Action Strategy3 for more information.
Comment: Pretreatment
One commenter recommended source identification of PFAS and stronger pretreatment
program requirements.
Response: The Division reviewed the City's pretreatment program and did not find it to be
deficient. Once an issued permit or permit renewal becomes effective, the permittee has 180 days
to submit a written technical evaluation of the need to revise local limits within its pretreatment
program. This may include revising, updating, or adding to the list of Significant Industrial Users
(SIUs). The Permittee is required to submit an updated Long -Term Monitoring Program (LIMP),
including an updated Industrial Waste Survey (IWS) and a review of pollutants of concern (POCS)
to reflect pollutants in Industrial User Permits (IUPs) and the facility's residuals (a.k.a. biosolids)
land application program permit. Since PFAS requirements are proposed in the NPDES permit
renewal for the City of Asheboro, the City's pretreatment program must consider PFAS as POCs
and include them in updated LIMP, IWS, IUPs and Headworks Analysis (HWA), which trigger
review of limits and monitoring for POCs including the PFAS chemical class.
1,4-Dioxane Comments
Comment: 1,4-Dioxane limits and monitoring
Three commenters noted support of inclusion of 1,4-dioxane weekly monitoring and limitations
based on the use of the Instream Target Value (EPA -IRIS cancer risk of 0.35 µg/L) and average
z https://www.epa.gov/newsreleases/epa-issues-guidance-states-reduce-harmful-pfas-pollution
3 https://www.deq.nc.gov/genx/nc-deq-action-strategy-pfas/open
Page 6 of 13
annual flow in the Deep River at the next downstream water supply watershed boundary for
development of site -specific WQBELs. One commenter requested the Division to consider
cumulative effects of all upstream 1,4-dioxane discharges on downstream water supply surface
waters. Two commenters challenged the authority of the Division to implement 1,4-dioxane
effluent limitations based on the Instream Target Value, believe that the Division is incorrectly
implementing 15A NCAC 02B .0208 and that the 1,4-dioxane instream target value lacks a tie to
scientific consensus. Two commenters believe that the Rules Review Commission rejecting the
Environment Management Commission's proposed rulemaking to adopt a numeric standard for
1,4-dioxane during the 2022-2023 Triennial Review due to the lack of a cost -benefit analysis
prevents the Division from implementing the Instream Target Value. Two commenters challenge
that the determination of 1,4-dioxane as a likely human carcinogen is not enough to treat the
chemical as a carcinogen. One commenter asserts that the December 2020 EPA Final Risk
Assessment related to 1,4-dioxane finding no unreasonable risks to the environment from
conditions of 1,4 dioxane use, no unreasonable risks to consumers or bystanders from any
conditions of 1,4 dioxane use and no unreasonable risks to the general population related to 1,4
dioxane means that no 1,4-dioxane requirements should be implemented. One commenter
challenged the Division's use of the EPA Technical Support Document for calculating a daily
maximum limitation for 1,4-dioxane. One commenter challenged the Division's decision to
consider downstream drinking water uses. One commenter asserted that technological and
economic limitations make compliance with a 0.35 µg/L standard in a receiving stream practically
unachievable. One commenter challenged the consistency of the Division's actions in NPDES
permits for 1,4-dioxane.
Response: Per 15A NCAC 02B .0203, "Water quality based effluent limitations and management
practices for direct or indirect discharges of waste or for other sources of water pollution shall be
developed by the Division such that the water quality standards and best usage of receiving
waters and all downstream waters will not be impaired." As such, the Division is required to
protect for the downstream WS designation. 1,4-dioxane is completely miscible in water and
resistant to biodegradation. It is assumed that concentrations of 1,4-dioxane discharged from the
WWTP will be equivalent at the direct discharge to Hasketts Creek, a class C waterbody, and the
nearest downstream water supply (WS-V) boundary, located in the Deep River 1.0 mile upstream
of Tysons Creek and 43.5 miles downstream of the outfall. While the drinking water intake in this
WS-V section of the Deep River is currently inactive, it is still considered a potential drinking water
source, which can become active in the future, and is subject to WS protections.
Per 15A NCAC 02B .0218(4), "No discharge of sewage, industrial wastes, or other wastes shall be
allowed that have an adverse effect on human health or that are not treated in accordance with
the permit or other requirements established by the Division pursuant to G.S. 143-215.1. Upon
request by the Commission, dischargers or industrial users subject to pretreatment standards
shall disclose all chemical constituents present or potentially present in their wastes and
chemicals that could be spilled or be present in runoff from their facility which may have an
adverse impact on downstream water quality. These facilities may be required to have spill and
treatment failure control plans as well as perform special monitoring for toxic substances."
Page 7 of 13
Per 15A NCAC 02B .0208(a), "Toxic Substances: the concentration of toxic substances, either alone
or in combination with other wastes, in surface waters shall not render waters injurious to aquatic
life or wildlife, recreational activities, or public health, nor shall it impair the waters for any
designated uses." 15A NCAC 02B .0208(a) further outlines how the "narrative standard for toxic
substances and numerical standards applicable to all waters" shall be interpreted.
The EPA Integrated Risk Information System (IRIS) is run by EPA toxicologists who put together a
risk assessment via a 6-step process with both internal and external experts and a public comment
aspect. Through this, EPA provides a reference dose to act as a gold standard for use in various
exposure pathways.
Per EPA's IRIS Chemical Assessment Summary for 1,4-Dioxane; CASRN 123-91-1, "[i]n accordance
with the Guidelines for Carcinogen Risk Assessment (U.S. EPA, 2005a), 1,4-dioxane is
characterized as "likely to be carcinogenic to humans." This characterization is based on the
following findings: (1) inadequate evidence of carcinogenicity in humans, and (2) sufficient
evidence in animals (i.e., hepatic tumors in multiple species [three strains of rats, two strains of
mouse, and in guinea pigs]; mesotheliomas of the peritoneum, mammary, and nasal tumors have
also been observed in rats following 2 years of oral exposure to 1,4- dioxane)." Lack of sufficient
studies of the carcinogenicity of 1,4-dioxane in humans is not uncommon considering toxicological
testing for carcinogenicity of chemicals in humans is not conducted. The identification of 1,4-
dioxane as 'likely to be carcinogenic to humans" was further corroborated in EPA's December
2020 Final Risk Evaluation for 1,4-Dioxane CASRN:123-91-1. 15A NCAC 02B .0208 provides
regulations regarding implementation of the narrative standard for toxic substances and
numerical standards applicable to all waters for non -carcinogens and carcinogens. As one cannot
definitively claim that 1,4-dioxane is a non -carcinogen, the implementation of 15A NCAC 02B
.0208(a)(2)(B) is appropriate for protection of downstream drinking water uses.
Per 15A NCAC 02B .0208(a)(2)(B), "For carcinogens, the concentrations of toxic substances shall
not result in unacceptable health risks and shall be based on a Carcinogenic Potency Factor (CPF).
An unacceptable health risk for cancer shall be more than one case of cancer per one million
people exposed (10-6 risk level).
As described earlier, toxicological testing for carcinogenicity of chemicals in humans is not
conducted. However, there are mathematical models that extrapolate the dose that caused a
toxic effect in the animal model to an equivalent dose in humans. The EPA uses Benchmark Dose
Software to conduct these calculations. These calculations are where the Human Equivalency
Dose (HED) is determined. The 95% lower bound estimate of exposure and the central estimate
of exposure of the HED are used to determine what the slope of the linear extrapolation is.
EPA's IRIS used the default linear extrapolation, specifically a Low -Dose Extrapolation Approach,
to determine an oral slope factor of 0.1 mg/kg/day and the drinking water unit risk is 2.9 x 10-6
µg/L and calculates that the drinking water concentration representing a 1 x 10-6 cancer risk level
Page 8 of 13
for 1,4-dioxane is 0.35 µg/L. This value has been set as an Instream Target Value for chronic
exposure to 1,4-dioxane.
EPA's Nationally Recommended Water Quality Criteria and Instream Target Values identified by
the Division's Standards and Classifications Branch provide the Division with numeric aids for
implementing the narrative standard. Application of Instream Target Values (ISTV) in order to
comply with the narrative standard has occurred in many permits prior to the application of the
1,4-dioxane ISTV in this permit.
For consideration of the downstream drinking water uses, allowable discharge concentrations
were calculated for both the direct discharge to Class C Hasketts Creek and for the nearest
downstream water supply (WS-V) boundary, and the more restrictive concentration was selected
for protection of downstream uses.
Per 15A NCAC 02B .0206(a)(4)(B), "[t]he mean annual flow to protect human health from
carcinogens through the consumption of water, fish, and shellfish unless site specific fish
contamination concerns necessitate the use of an alternative design flow." The applicable mean
annual flows for each respective location, the discharge point into Hasketts Creek and the
downstream WS-V boundary, were used in calculation of the allowable discharge concentrations.
EPA IRIS also determined an ISTV for 1,4-dioxane outside of WS waters of 80 µg/L, which was used
in calculation of the allowable discharge concentration for 1,4-dioxane in the direct discharge to
Class C Hasketts Creek. As the calculated allowable discharge concentration at the downstream
drinking water supply boundary was more protective, it was implemented in the NPDES permit
NC0026123.
In the 1991 Technical Support Document, Section 5.4.4 EPA Recommendations for Permitting of
Human Health Protection, EPA recommends and provides guidance for the calculation and use of
maximum daily limitations based on effluent variability and the number of samples per month
using the multipliers provided within the document in Table 5-3. The Division used this
recommendation and guidance to develop daily maximum limitations for use in the NPDES permit.
Daily maximum limitations accompanied by weekly monitoring mitigate industrial slugs from
dischargers and reduce risk of potential chronic impacts at downstream drinking water utilities.
The calculated allowable discharge concentration for the Asheboro WWTP is considered
technologically achievable with pretreatment action.
The Division is assessing other dischargers for 1,4-dioxane and protection of the downstream
water uses. One comment noted permitting actions for DAKAmericas, NC0003719. This permit is
being reevaluated and appropriate action is to be proposed before issuance.
Please note that the Rules Review Commission's decision to reject the Environment Management
Commission's proposed rulemaking to adopt a numeric standard for 1,4-dioxane at the 2022-
Page 9 of 13
2023 Triennial Review does not in any way supersede the requirements currently enacted in the
15A NCAC 02B rules, including the narrative standard described in 15A NCAC 02B .0218(4).
Comment: Use of 1,4-Dioxane Permitting Strategy
One commenter challenged the Division's use of the 2022 DWR NPDES Strategy for 1,4-dioxane
due to the strategy being in draft form and not signed by a Division or Agency official. The same
commenter believes that use of the strategy purports to establish regulation outside of the
Agency's rulemaking authority.
Response: The 2022 DWR NPDES Strategy (the Strategy) for 1,4-dioxane provides permit writers
with guidance for identifying, investigating, reducing and eliminating the discharge of 1,4-
dioxane from NPDES dischargers. While the Strategy provides a framework of recommended
actions and a prioritization plan for permit writers by developing Action Level Tiers, the
recommended actions are consistent with the Division's approach to other parameters of concern
(e.g. effluent monitoring and limits assessment). The limits incorporated in the permit were
developed in accordance with rules set out in the 15A NCAC 02B rules, and not a result of any
guidelines outlined in the Strategy.
Comment: 1,4-Dioxane Schedule of Compliance
Three commenters requested that the 1,4-dioxane compliance schedule be reduced from 5 years
to 3 years since the City of Asheboro has known of the presence of 1,4-dioxane in their waste
stream since 2018 and has already identified sources.
Response: The City of Asheboro identified the presence of 1,4-dioxane in their facility's
wastewater as early as 2018. However, the technology and understanding surrounding 1,4-
dioxane has continually evolved since 2018 and the City has taken action to identify likely sources
of the parameter to their facility. Due to the nature of mitigation of 1,4-dioxane in WWTP
discharges, the City continues to need time to achieve compliance with the new permit limitations.
The City will be working with their industries, conducting sampling, and investigating other
necessary options for reduction of 1,4-dioxane concentrations in their effluent, which takes time.
Five years has been determined to be an appropriate amount of time to conduct mitigation
efforts. In the interim, the City is required to achieve noted reductions throughout the term of the
permit to demonstrate continual progress in their efforts. As such, the 5-year compliance period
with tiered limitations has been maintained.
Comment: 1,4-Dioxane Downstream Utility Notification
One commenter supported the requirement for notification of downstream utilities in the event
of a 1,4-dioxane discharge at levels greater than the allowable discharge concentration but
requested that at least two points of contact be included in the utility list due to staff turnover.
Page 10 of 13
Response: The request for a secondary contact for each downstream utility has been considered
and the Utility Contact List has been updated to include an additional contact for each listed
utility.
IV. Recommendations
Based on the review of public comments, the draft permit and additional information, the North
Carolina General Statutes and Administrative Code, and discussions with DWR staff, I offer the
following comments and recommendations for issuance of a renewed NPDES Permit for City of
Asheboro — Asheboro Wastewater Treatment Plant (NC0026123).
Based upon the information available, I recommend that the NPDES Permit renewal for City of
Asheboro — Asheboro Wastewater Treatment Plant (NC0026123) be issued subject to the
conditions included below:
The Downstream Utility Contact List should include a secondary point of contact for each
downstream utility to ensure that the utilities are notified in the event of elevated 1,4-dioxane
levels reported in the Asheboro WWTP effluent.
It is further recommended that DWR include any additional conditions necessary to ensure that
the permit will meet state water quality standards.
V. Summary
The hearing officer thoroughly reviewed all public comments received and the project record in
the context of all pertinent statutes and regulations governing the review of the City of
Asheboro's Wastewater Treatment Plant's NPDES permit renewal. Based on this information, it
is the hearing officer's recommendation that the NPDES Permit No. NCO026123 renewal be
issued and subject to the conditions recommended in Section IV. It is further recommended that
DWR include any additional conditions necessary to ensure that the permit will meet state water
quality standards.
E DocuSigned
by:
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Ramesh Ravella, Hearing Officer
Page 11 of 13
8/17/2023
Date
VI. Appendices (available on Laserfiche)
A. March 21, 2016 — NPDES Permit Renewal Application
• Laserfiche File Name: NC0026123_Renewal (Application)_20160321
Laserfiche link:
https://edocs.deg.nc.gov/WaterResources/DocView.aspx?id=361060&dbid=0&repo=Water
Racni irrac
B. May 9, 2018 — First Draft NPDES Permit
• Laserfiche File Name: NC0026123_Draft Permit_20180501
Laserfiche link:
https://edocs.deg.nc.gov/WaterResources/DocView.aspx?id=665769&dbid=0&repo=Water
Racni irroc
C. December 6, 2022 — Second Draft NPDES Permit
• Laserfiche File Name: NC006123_Draft Permit_20221206
Laserfiche link:
https://edocs.deg.nc.gov/WaterResources/DocView.aspx?id=2601378&dbid=0&repo=Wate
rRacni irrac
D. December 6, 2022 — Draft Fact Sheet
• Laserfiche File Name: NC0026123 Fact Sheet 20221207
Laserfiche link:
https://edocs.deg.nc.gov/WaterResources/DocView.aspx?id=2601402&dbid=0&repo=Wate
rResources
E. Comments to Draft Permit
• Laserfiche File Name: NC0026123 Comments 20230109
Laserfiche Link:
https://edocs.deg.nc.gov/WaterResources/DocView.aspx?id=26364ll&dbid=0&repo=Wate
rRocni irrar
• Laserfiche File Name: NC0026123_Comments_20230109 (2)
Laserfiche Link:
https://edocs.deg.nc.gov/WaterResources/DocView.aspx?id=2636425&dbid=0&repo=Wate
rResources
• Laserfiche File Name: NC0026123 Comments 20230111
Laserfiche Link:
https://edocs.deg.nc.gov/WaterResources/DocView.aspx?id=2639566&dbid=0&repo=Wate
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• Laserfiche File Name: NC0026123 Comments 20230119
Laserfiche Link:
https://edocs.deg.nc.gov/WaterResources/DocView.aspx?id=2651502&dbid=0&repo=Wate
rResources
• Laserfiche File Name: NC0026123 Comments 20230123
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Laserfiche Link:
https://edocs.deg.nc.gov/WaterResources/DocView.aspx?id=2652381&dbid=0&repo=Wate
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• Laserfiche File Name: NC0026123 Comments 20230127
Laserfiche Link:
https://edocs.deg.nc.gov/WaterResources/DocView.aspx?id=2659279&dbid=0&repo=Wate
rResources&cr=1
• Laserfiche File Name: NC0026123 Comments 20230130
Laserfiche Link:
https://edocs.deg.nc.gov/WaterResources/DocView.aspx?id=2663569&dbid=0&repo=Wate
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• Laserfiche File Name: NC0026123 Comments 20230522
Laserfiche Link:
https://edocs.deg.nc.gov/WaterResources/DocView.aspx?id=2804606&dbid=0&repo=Wate
rResources&cr=1
F. Notice of Public Hearing
• Laserfiche Filename: NC0026123_Affidavit_20230509
Laserfiche link:
https://edocs.deg.nc.gov/WaterResources/DocView.aspx?id=2786122&dbid=0&repo=Wate
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G. Public Hearing Speaker and Non -Speaker Sign In sheets
• Laserfiche Filename: NC0026123 Other 20230608
Laserfiche link:
https://edocs.deg.nc.gov/WaterResources/DocView.aspx?id=2826746&dbid=0&repo=Wate
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H. Public Hearing recording including oral comments
• File Name: Asheboro PH
Laserfiche link:
https://edocs.deg.nc.gov/WaterResources/DocView.aspx?id=2824543&dbid=0&repo=Wate
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I. Written comments received after the public hearing, within the comment period
• Laserfiche Folder Name: NC0026123_Comments_20230524
Laserfiche link:
https://edocs.deg.nc.gov/WaterResources/DocView.aspx?id=2826803&dbid=0&repo=Wate
rResources
• Laserfiche Folder Name: NC0026123_Comments_20230526
Laserfiche Link:
https://edocs.deg.nc.gov/WaterResources/DocView.aspx?id=2812335&dbid=0&repo=Wate
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