NC0083909_Draft Permit_20171004

Water Resources
ENVIRONMENTAL QUALITY
October 4, 2017
Mr. Ken Flatt, Utilities Director
Dare County
600 Mustian Street
Kill Devil Hills, NC 27948
ROY COOPER
Gove no
MICHAEL S REGAN
Secs elnry
S JAY ZIMMERMAN
Drrec[ot
Subject: Draft NPDES Permit NCO083909
Rodanthe/Waves/Salvo Reverse Osmosis WTP
Class PC-1
Dare County
Dear Mr. Flatt:
The Division has reviewed your request to renew the subject permit. Please review this draft
carefully to ensure your thorough understanding of the information, conditions, and requirements
it contains.
The draft permit includes the following significant changes from the existing permit:
➢ Section A. (4) has been added to require electronic submission of effluent data, and a
footnote has been added in Section A. (1). Federal regulations require electronic
submittal of all discharge monitoring reports (DMRs).
➢ Regulatory citations have been added to the permit.
➢ Parameter codes have been updated in Section A. (1).
➢ Outfall map has been updated.
➢ Language has been updated on the Supplement to Permit Cover Sheet based on current
NPDES permit formatting.
➢ The facility address has been updated on the cover sheet and Supplement to Permit Cover
Sheet per the permit renewal application.
➢ Monitoring and limits have been added for total residual chlorine in Section A. (1) per the
current water treatment plant strategy.
➢ Monitoring has been added for turbidity in Section A. (1) per the current water treatment
plant strategy.
➢ The column for weekly average limits in Section A. (1) has been removed.
➢ Limits have been added for Total Nickel and Total Zinc based on a reasonable potential
to exceed water quality standards.
➢ Limits have been removed for Total Selenium and monitoring has been reduced to
quarterly based on a reasonable potential analysis.
➢ Limits for Total Arsenic have been changed based on a reasonable potential to exceed
current water quality standards.
➢ Monitoring has been removed for the following parameters in Section A. (1): Total
Cadmium, Total Chromium, Total Cyanide, Total Lead, Total Mercury, and Total Silver.
These parameters did not display a potential to exceed water quality standards.
State of North Carolina I Environmental Quality I Water Resources
1617 Mail Service Center I Raleigh, NC 27699-1617
919 807 6300 919-807-6389 FAX
https //deq nc gov/about/divisions/water-resources/water-resources-permits/wastewater-branch/npdes-wastewater-permits

➢ Language has been added in Section A. (1) stating "All samples collected should be from
a representative discharge event" per current NPDES permit guidelines.
➢ The language and footnote for aquatic toxicity monitoring has been updated in Section A.
(1), and the language in Section A. (2) has been updated.
➢ Section A. (3) has been added requiring a discharge alternatives evaluation as the facility
has a history of failed toxicity tests.
Please note that the receiving stream is listed as an impaired waterbody on the North Carolina
303(d) Impaired Waters List. Addressing impaired waters is a high priority with the Division,
and instream data will continue to be evaluated. If there is noncompliance with permitted
effluent limits and stream impairment can be attributed to your facility, then mitigative measures
may be required.
Whole Effluent Toxicity test results submitted during the past three years have demonstrated that
the Water Treatment Plant's effluent is showing potential for causing aquatic toxicity in the
receiving stream. As a result, the Rodanthe/Waves/Salvo RO WTP shall perform a Discharge
Alternatives Evaluation as described in Section A. (3) of this permit. This evaluation is being
requested to determine whether there are any economical and technologically feasible
alternatives available to the Rodanthe/Waves/Salvo RO WTP to comply with all NC Water
Quality Standards. The permittee will be given approximately one permit cycle to evaluate and
document possible treatment/discharge alternatives to eliminate aquatic toxicity. The evaluation
shall be submitted with the permittee's next permit renewal application and will be carefully
reviewed by the Division and the results will be used in the development of a compliance
schedule or possible variance request for the Rodanthe/Waves/Salvo RO WTP.
With this notification, the Division will solicit public comment on this draft permit by publishing
a notice in newspapers having circulation in the general Tyrrell County area, per EPA
requirements. Please provide your comments, if any, to me no later than 30 days after
receiving this draft permit.
Following the 30-day public comment period, the Division will review all pertinent comments
and take appropriate action prior to issuing a final permit. If you have questions concerning the
draft, please contact me at 919-807-6333, or via e-mail [[e-mail]].
Sincerely,
Brianna Young
Compliance and E pedited Permitting Unit
cc• NPDES Files
ec. Washington Regional Office
WSS/Aquatic Toxicology Branch
DMF/Shellfish Sanitation

Permit NCO083909
STATE OF NORTH CAROLINA
DEPARTMENT OF ENVIRONMENTAL QUALITY
DIVISION OF WATER RESOURCES
PERMIT
TO DISCHARGE WASTEWATER UNDER THE
NATIONAL POLLUTANT DISCHARGE ELIMINATION SYSTEM
PDES
In compliance with the provision of North Carolina General Statute 143-215.1, other lawful standards
and regulations promulgated and adopted by the North Carolina Environmental Management
Commission, and the Federal Water Pollution Control Act, as amended,
Dare County
is hereby authorized to discharge wastewater from a facility located at the
Rodanthe/Waves/Salvo Reverse Osmosis Water Treatment Plant
23697 Highway 12
Rodanthe
Dare County
to receiving waters designated as Blackmar Gut in the Pasquotank River Basin in accordance with
effluent limitations, monitoring requirements, and other conditions set forth in Parts I, II, III and IV
hereof.
This permit shall become effective.
This permit and authorization to discharge shall expire at midnight on December 31, 2022.
Signed this day.
S. Jay Zimmerman, P.G.
Director, Division of Water Resources
By Authority of the Environmental Management Commission
Page 1 of 8

Permit NCO083909
SUPPLEMENT TO PERMIT COVER SHEET
All previous NPDES Permits issued to this facility, whether for operation or discharge, are hereby
revoked. The exclusive authority to operate this facility arises under this permit. The authority to
operate the facility under previously issued permits bearing this number is no longer effective. The
conditions, requirements, terms and provisions of this permit authorizing discharge under the
NPDES govern discharges from this facility.
Dare County
is hereby authorized to:
Continue to operate a Reverse Osmosis water treatment plant with a discharge of reverse osmosis
concentrate reject water. This water treatment plant currently has a design potable flowrate of 1.25
MGD and a maximum, monthly average wastewater discharge of 0.188 MGD. This facility is
located at 23697 Highway 12, Rodanthe, NC in Dare County. Water and wastewater treatment
consists of:
• Replaceable cartridge filters
• Inhibitor addition system
• Reverse osmosis unit
• Submerged discharge
2. Discharge from said drinking water treatment facility at the location specified on the attached map
into Blackmar Gut [stream segment 30-22-13], currently classified SA-HQW waters in subbasin 03-
01-55 [HUC: 0301020515] in the Pasquotank River Basin.
Page 2 of 8

Permit NCO083909
PART I.
A. (L) EFFLUENT LIMITATIONS AND MONITORING REQUIREMENTS
[15A NCAC 02B .0400 et seq., 02B .0500 et seq.]
During the period beginning on the effective date of the permit and lasting until expiration, the Permittee is
authorized to discharge through a diffuser from Outfall 001. Such discharges shall be limited and monitored' by
the Permittee as specified below:
EFFLUENT CHARACTERISTICS
(Parameter Codes)
LIMITS
MONITORING
REQUIREMENTS
Monthly
Average
Daily
Maximum
Measurement
frequencyfEqquency
Sample
Type
Sample
Location z
Flow 50050
/ Continuous
Recording
E
Dissolved Oxygen 3 00300
'
Monthly
Grab
E, U, D
Salinity 00480
'
Monthly
Grab
E, U, D
Conductivity 00094
Monthly
Grab
E, U, D
H 00400
Not < 6 8 S U nor >`8 5/S.U.
2/Month
Grab
E
H 00400
, '
Monthly
Grab
U, D
Total Residual Chlorine a 50060
13
/I
2/Month
Grab
E
Total Dissolved Solids 70295
Monthly
Grab
E
Turbidity 00070
r_.
Monthly
Grab
E
Total Arsenic 01002
5 pg/l
5 pg/1
Monthly
Grab
E
Total Zinc, ll 01092
42 8 /L
47.6 /L
Monthly
Grab
E
Total Nickel 01067
4.15 /L
37.35 pg/L
Monthly
Grab
E
Total Copper, /l 01042
_
Quarterly
Grab
E
Total Selenium , 01147
Quarterly
Grab
E
Ammonia Nitrogen C0610
/
Monthly
Grab
E
Total Nitrogen 5 ,C0600
r'
Quarterly
Grab
E
Total Phosphorus(C0665),Quarterly
Grab
E
WET Monitoring 6 TGE3E
Monitor & Re o-
Quarterly
Grab
E
Footnotes
1 The permittee shall submit discharge monitoring reports electronically using the NC DWR's eDMR application system
[see Section A (4)]
2. E = Effluent, effluent samples shall be collected at point after nuxing of effluent wastewater from all treatment units and
prior to discharge, unless otherwise noted U = Upstream, 27 feet north of the discharge outfall, D = Downstream, 50 feet
south of the discharge outfall.
3 The permittee may petition the Division to have Dissolved Oxygen (DO) monitoring removed as part of the next permit
renewal application The facility must demonstrate that the discharge has no significant impact on the DO and temperature
levels in the receiving stream I
4 Limit and monitor only if the facility adds chlorine or chlorine derivatives to water that is eventually discharged The
Division shall consider all effluent TRC values reported below 50 µg/L to be in compliance with the permit However,
the Pernuttee shall continue to record and submit all values reported by a North Carolina certified laboratory including
field certified), even if these values fall below 50 µg/L
5. Total Nitrogen (TN) = (NO2-N + NO3-N) + TKN
6 Acute Toxicity 24-hr Pass/fail Monitoring January, April, July, and October Permittee shall use mysid shrimp as the test
organism unless another orgamsm of equal or greater sensitivity is deemed more appropriate based on the characteristics
of the discharge and receiving stream See Special condition A. (2) for details
All samples collected should be from a representative discharge event.
There shall be no discharge of floating solids or visible foam in other than trace amounts.
Page 3 of 8

Permit NCO083909
A. (2.) ACUTE TOXICITY PASS/FAIL MONITORING ONLY (QUARTERLY)
[15A NCAC 02B .0500 et seq.]
The permittee shall conduct acute toxicity tests on a quarterly basis using protocols defined in the North
Carolina Procedure Document entitled "Pass/Fail Methodology For Determining Acute Toxicity In A
Single Effluent Concentration" (Revised -December 2010 or subsequent versions). The monitoring shall
be performed as a Mysid Shrimp (Mysidopsis Bahia) 24 hour static test. The effluent concentration at
which there may be at no time significant acute mortality is 90% (defined as treatment two in the
procedure document). The tests will be performed during the months of January, April, July, and
October. These months signify the first month of each three month toxicity testing quarter assigned to
the facility. Effluent sampling for this testing must be obtained during representative effluent discharge
and shall be performed at the NPDES permitted final effluent discharge below all treatment processes.
All toxicity testing results required as part of this permit condition will be entered on the Effluent
Discharge Monitoring Form (MR-1) for the month in which it was performed, using the parameter code
TGE3E. Additionally, DWR Form AT-2 (original) is to be sent to the following address:
Attention: North Carolina Division of Water Resources
Water Sciences Section/Aquatic Toxicology Branch
1621 Mail Service Center
Raleigh, NC 27699-1621
Completed Aquatic Toxicity Test Forms shall be filed with the Water Sciences Section no later than 30
days after the end of the reporting period for which the report is made.
Test data shall be complete and accurate and include all supporting chemical/physical measurements
performed in association with the toxicity tests, as well as all dose/response data. Total residual chlorine
of the effluent toxicity sample must be measured and reported if chlorine is employed for disinfection of
the waste stream.
Should there be no discharge of flow from the facility during a month in which toxicity monitoring is
required, the permittee will complete the information located at the top of the aquatic toxicity (AT) test
form indicating the facility name, permit number, pipe number, county, and the month/year of the report
with the notation of "No Flow" in the comment area of the form. The report shall be submitted to the
Water Sciences Section at the address cited above.
Should the permittee fail to monitor during a month in which toxicity monitoring is required, then
monthly monitoring will begin immediately. Upon submission of a valid test, this monthly test
requirement will revert to quarterly in the months specified above.
Should any test data from either these monitoring requirements or tests performed by the North Carolina
Division of Water Resources indicate potential impacts to the receiving stream, this permit may be re-
opened and modified to include alternate monitoring requirements or limits.
NOTE: Failure to achieve test conditions as specified in the cited document, such as minimum control
organism survival and appropriate environmental controls, shall constitute an invalid test and will
require immediate follow-up testing to be completed no later than the last day of the month following
the month of the initial monitoring.
Page 4 of 8

Permit NCO083909
USE OF A DIFFERENT TEST ORGANISM
The permittee may request the use of a different test organism upon documentation that the alternate test
organism would provide an equal or greater level of protection and is appropriate based on the
characteristics of the discharge and receiving stream. Such documentation would consist of one of the
following:
1. For saltwater classified streams, a fathead minnow may be assigned as the acute testing species if
the salinity of the receiving stream at the point of discharge is <5 ppt throughout the tidally
influenced cycle. This determination may be based on the best professional judgment of DWQ
staff or data collection provided by the permittee and approved by DWQ staff. This evaluation
should include vertical profiles of salinity/conductivity measurements at both high tide and low
tide over several 24 hr cycles.
2. Three consecutive "side -by -side" tests with results indicating that the alternate test organism is as
or more sensitive to the facility's effluent. Each test series would consist of two separate toxicity
tests conducted on the same sample of effluent with the length of exposure specified by the permit,
the only difference between the tests being the organism used.
3. An alternate plan developed by the permittee and approved by the Aquatic Toxicology Unit that
demonstrates an equal level of protection is offered by the test organism.
For items 2 and 3, it must also be demonstrated that viable and standardized culture techniques are
available for that organism and standardized testing methodologies have been developed and
validated. This demonstration should meet guidance provided by EPA in Section 6 of EPA-821-R-02-
012, Short Term Methods for Estimating the Acute Toxicity of Effluents and Receiving Waters to
Freshwater Organisms. Fifth Edition, 2002.
A. (3.) DISCHARGE ALTERNATIVES EVALUATION
The Permittee shall assess potential alternatives to eliminate Whole Effluent Toxicity (WET) test failures.
This evaluation shall assess the feasibility of all the following alternatives.
1. Connect discharge to a WWTP: Determine whether the wastewater can be discharged to a wastewater
treatment plant. Approval or disapproval from the plant operator should be acquired.
2. Obtain a Non -discharge permit: Eliminate the surface water discharge by obtaining a non -discharge
permit for spray irrigation, infiltration, or subsurface disposal (on -site drainfield,
infiltration gallery, injection wells).
3. Install Wastewater Treatment: Install improved wastewater treatment to enable the facility effluent to
consistently pass the WET test. If this is not technically feasible or cost prohibitive,
please explain and provide estimated costs.
4. Use Alternative Water Treatment Source: Obtain drinking water from another source (nearest
County, City, or Town or other wells) so the discharge or toxicity problem is
eliminated.
5. Use Alternative Water Treatment Method: Install alternative and/or innovative water treatment
methods or operational improvements that do not produce toxic wastewaters. For
Page 5of8

Permit NCO083909
example, install a recycle iron/manganese filtration system with no discharge or
combine discharge with WWTP or cooling water effluents.
6. Discharge to a Larger waterbody/Perform a dilution model: Relocate the facility's discharge to a
larger receiving waterbody to eliminate or reduce toxic impacts to the receiving
waterbody given the increased dilution. If applicable, perform a dilution model to
receive allowance for stream dilution in WET test.
7. Combination of Alternatives: Employ any combination of the alternatives listed above that would
result in eliminating or decreasing toxicity until a more feasible solution becomes
available.
The evaluation shall include a present value of costs analysis for all technologically feasible options as
outlined in the Division's "Engineering Alternatives Analysis Guidance Document." This Document can be
found at: http://portal.ncdenr.org/web/wq/swp/ps/npdes/permits.
This evaluation is being requested to determine whether there are any economical and technologically
feasible alternatives available to the Permittee to address aquatic toxicity in the plant effluent. Based upon
the evaluation, please identify viable alternatives and present an implementation schedule and project
timeline for the preferred alternative. The Permittee'shall submit the Discharge Alternatives Evaluation to the
Division along with the submission of their next permit renewal application (due 6 months prior to permit
expiration on December 31, 2022) to:
NC DENR [Division of Water Resources / Water Quality Permitting
NPDES, Wastewater Branch
1617 Mail Service Center, Raleigh, NC 27699-1617
A. (4.) ELECTRONIC REPORTING OF MONITORING REPORTS
[NCGS 143-215.1 (b)]
Federal regulations require electronic submittal of all discharge monitoring reports (DMRs) and program
reports. The final NPDES Electronic Reporting Rule was adopted and became effective on December
21, 2015.
NOTE: This special condition supplements or supersedes the following sections within Part II of this
permit (Standard Conditions for NPDES Permits):
• Section B. (11.)
• Section D. (2.)
• Section D. (6.)
• Section E. (5.)
Signatory Requirements
Reporting
Records Retention
Monitoring Reports
1. Reporting Requirements [Supersedes Section D. (2.) and Section E. (5.) (a)1
The permittee shall report discharge monitoring data electronically using the NC DWR's Electronic
Discharge Monitoring Report (eDMR) internet application.
Monitoring results obtained during the previous month(s) shall be summarized for each month and
submitted electronically using eDMR. The eDMR system allows permitted facilities to enter monitoring
Page 6 of 8

Permit NC0083909
data and submit DMRs electronically using the internet. Until such time that the state's eDMR
application is compliant with EPA's Cross -Media Electronic Reporting Regulation (CROMERR),
permittees will be required to submit all discharge monitoring data to the state electronically using
eDMR and will be required to complete the eDMR submission by printing, signing, and submitting one
signed original and a copy of the computer printed eDMR to the following address:
NC DEQ / Division of Water Resources / Water Quality Permitting Section
ATTENTION: Central Files
1617 Mail Service Center
Raleigh, North Carolina 27699-1617
If a permittee is unable to use the eDMR system due to a demonstrated hardship or due to the facility
being physically located in an area where less than 10 percent of the households have broadband access,
then a temporary waiver from the NPDES electronic reporting requirements may be granted and
discharge monitoring data may be submitted on paper. DMR forms (MR 1, 1.1, 2, 3) or alternative forms
approved by the Director. Duplicate signed copies shall be submitted to the mailing address above. See
"How to Request a Waiver from Electronic Reporting" section below.
Regardless of the submission method, the first DMR is, due on the last day of the month following the
issuance of the permit or in the case of a new facility, on the last day of the month following the
commencement of discharge.
Starting on December 21, 2020, the permittee must- electronically,report the following compliance
monitoring data and reports, when applicable:.
• Sewer Overflow/Bypass Event Reports;
• Pretreatment Program Annual Reports; and'
• Clean Water Act (CWA) Section 316(b) Annual Reports.
The permittee may seek an electronic reporting waiver from the Division (see "How to Request a
Waiver from Electronic Reporting" section below).
2. Electronic Submissions
In accordance with 40 CFR 122.41(1)(9), the permittee must identify the initial recipient at the time of
each electronic submission. The perrmittee should use the EPA's website resources to identify the initial
recipient for the electronnc submission.
Initial recipient of electronic NPDES information from NPDES-regulated facilities means the entity
(EPA or the state authorized by EPA to implement the NPDES program) that is the designated entity for
receiving electronic NPDES data [see 40 CFR 127.2(b)].
EPA plans to establish a website that will also link to the appropriate electronic reporting tool for each
type of electronic submission and for each state. Instructions on how to access and use the appropriate
electronic reporting tool will be available as well. Information on EPA's NPDES Electronic Reporting
Rule is found at: https://www.federalreig ster.gov/documents/2015/10/22/2015-24954/national-
pollutant-discharge-elimination-system-npdes-electronic-reporting-rule.
Electronic submissions must start by the dates listed in the "Reporting Requirements" section above.
3. How to Request a Waiver from Electronic Regortin
Page 7of8

F
Permit NC0083909
The permittee may seek a temporary electronic reporting waiver from the Division. To obtain an
electronic reporting waiver, a permittee must first submit an electronic reporting waiver request to the
Division. Requests for temporary electronic reporting waivers must be submitted in writing to the
Division for written approval at least sixty (60) days prior to the date the facility would be required
under this permit to begin submitting monitoring data and reports. The duration of a temporary waiver
shall not exceed 5 years and shall thereupon expire. At such time, monitoring data and reports shall be
submitted electronically to the Division unless the permittee re -applies for and is granted a new
temporary electronic reporting waiver by the Division. Approved electronic reporting waivers are not
transferrable. Only permittees with an approved reporting waiver request may submit monitoring data
and reports on paper to the Division for the period that the approved reporting waiver request is
effective.
Information on eDMR and the application for a temporary electronic reporting waiver are found on the
following web page:
http://deq.nc..gov/about/divisions/water-resources/edmr
4. Signatory Requirements [Supplements Section B. (11.) (b) and Supersedes Section B. (11.) (d)1
All eDMRs submitted to the permit issuing authority shall be signed by a person described in Part II,
Section B. (I 1.)(a) or by a duly authorized representative of that person as described in Part II, Section
B. (I 1.)(b). A person, and not a position, must be delegated signatory authority for eDMR reporting
purposes.
For eDMR submissions, the person signing and submitting the DMR must obtain an eDMR user account
and login credentials to access the eDMR system. For more information on North Carolina's eDMR
system, registering for eDMR and obtaining an eDMR user account, please visit the following web
page:
http://deq.nc.gov/about/divisions/water-resources/edmr
Certification. Any person submitting an electronic DMR using the state's eDMR system shall make the
following certification [40 CFR 122.22]. NO OTHER STATEMENTS OF CERTIFICATION WILL
BE ACCEPTED:
"I certify, under penalty of law, that this document and all attachments were prepared under my
direction or supervision in accordance with a system designed to assure that qualified personnel
properly gather and evaluate the information submitted. Based on my inquiry of the person or persons
who manage the system, or those persons directly responsible for gathering the information, the
information submitted is, to the best of my knowledge and belief, true, accurate, and complete. I am
aware that there are significant penalties for submitting false information, including the possibility of
fines and imprisonment for knowing violations. "
5. Records Retention [Supplements Section D. (6.)]
The permittee shall retain records of all Discharge Monitoring Reports, including eDMR submissions.
These records or copies shall be maintained for a period of at least 3 years from the date of the report.
This period may be extended by request of the Director at any time [40 CFR 122.41 ].
Page 8 of 8

Y L D L I F E R E F
o Light
Paula
Approximate Facility Location
Uncle Jimmy�n12
Landing
4
Outfall
Greens Pt
Rlackmar Gut
Rodanthe•
12-.',...
12 ,
1 `• 12 `[:1 :::
Dare County
Rodanthe/Waves/Salvo Reverse Osmosis WTP
NPDES Permit NCO083909
Receiving Stream: Blackmar Gut Stream Class: SA; HQW
Stream Segment: 30-22-13 Sub -Basin #: 03-01-55
River Basin: Pasquotank HUC: 0301020515
County: Dare
N
SCALE
1:24,000
/4
Ja
LocationFacility
'ility Lc
scale not shown
LISGS
• .. Rodanthe
35.595560, -75.470280