The URL can be used to link to this page

Home My WebLink AboutNC0041530_Change-Page to Correct Error_20171006Water Resources Environmental Quality October 6, 2017 Mr. David G. Tolson, Plant & Systems Manager Ocracoke Sanitary District P0.Box 567 Ocracoke, NC 27960 Dear Mr. Tolson: ROY COOPER Governor MICHAEL S. REGAN Secretory S. JAY ZIMMERMAN Director Subject- Change -Page to Correct Error NPDES Permit NCO041530 Ocracoke Reverse Osmosis WTP 159 Water Plant Road, Ocracoke 27960 Hyde County The Division of Water Resources (the Division) became aware of an error in your recently issued permit (April 24, 2017). Mary Ann's Pond (Pamlico Sound) is not unpaired for Turbidity. In accordance with current water treatment plant permitting strategy Turbidity should be monitoring only. Thus, reducing the monitoring frequency from 2/month to monthly. Accordingly, we hereby forward the modified permit page to amend your permit correcting the effluent page to indicate that Turbidity is monitoring only with a measurement frequency of monthly. Additionally, the Turbidity footnote has been removed. Please insert this change page into your existing permit and discard the old page. We regret any inconvenience this causes your organization. Please note that this permit is not transferable except after notice to the Division. The Division may require modification or revocation and reissuance of the permit. This permit does not affect the legal requirements to obtain other permits which may be required by the Division of Water Resources or any other Federal, State, or Local governmental permits that may be required. If you have questions, or if we can be of further service, please contact Derek Denard at [derek denard@ncdenr.gov] or call (919) 807-6307. ,/Sinc-rely, S. Jay Zimmerman, P.G., Di cti`� o Division of Water Resources, NCDEQ Enclosure: NPDES Permit NCO041530 (Correction Page) hc: Central Files NPDES Program Files WaRO Files/ Attn: Robert Tankard ec Aquatic Toxicology Branch/ Susan Meadows [susan meadows@ncdenr gov] [draft permit, Fact Sheet] David G Tolson, Plant & Systems Manager, Ocracoke Sanitary District [Ocracokeh2o@yahoo com] Nothing Compares'-_,_ State of North Carolina 1 Environmental Quality 1617 Mail Service Center I Raleigh, North Carolina 27699-1617 919-707-9000 NPDES Permit NCO041530 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 this permit and lasting until expiration, the Permittee is authorized to discharge RO reject water from outfall 001. Such discharges shall be limited, monitored and reported' by the Permittee as specified below: EFFLUENT CHARACTERISTIC [PARAMETER CODES] LIMITS MONITORING REQUIREMENTS' Monthly Average Daily Maximum Measurement Frequency Sample Type Sample Location Flow (MGD) 50050 Continuous Recording Effluent pH (su) 00400 Not < 6 8 or > 8 5 standard units 2/Month Grab Effluent Turbidity (NTLI) 00070 Monitor & Report Monthly Grab Effluent Dissolved Oxygen (mg/L) 00300 Monthly Grab Effluent Salimty (ppth) 00480 Quarterly Grab Effluent Conductivity (µmhos/cm) 00094 Quarterly Grab Effluent Total Dissolved Solids (TDS) (mg/1) 70295 Quarterly Grab Effluent Ammoma Nitrogen (mg/1) C0610 Monitor & Report Quarterly Grab - Effluent TKN 2 (1119/1) NO3-N + NO2-N 2 (mg/1) TN 2 (mg/1) 00625 00630 C0600 Monitor & Report Monitor & Report Monitor & Report Quarterly Quarterly Quarterly Grab Grab Grab Effluent Effluent Effluent Total Phosphorus (mg/1) C0665 Monitor & Report Quarterly Grab Effluent Total Copper (µg/1) 3 01042 Quarterly Grab Effluent Acute WET Testing 4 TGE3E Quarterly Grab Effluent Footnotes 1 Effective December 21, 2016, begin submittmg Discharge Monitoring Reports electronically using NC DWR's eDMR application system See Condition A. (3.). 2. For a given wastewater sample, TN = TKN + NO3-N + NO2-N, where TN is Total Nitrogen, TKN is Total Kjeldahl Nitrogen, and NO3-N and NO2-N are Nitrate and Nitrite Nitrogen, respectively 3. All practical quantitation limits (PQL) must be sufficiently sensitive considering the respective water quality standard for each parameter [see Part II Section D (4.)] (For Total Copper a PQL of 2 µg/1 or better is recommended ) 4 Acute Whole Effluent Toxicity (WET) testing - testing of Mysidopsas bahia (Mysid shrimp) shall be performed as 24 - day pass/fail test at 90% effluent concentration, during February, May, August and November [See A (2 )] Conditions• • Samples shall be taken at the outfall but prior to mixing with the receiving waters. • There shall be no discharge of floating solids or foam visible in other than trace amounts Page 3 of 7 NPDES Permit NCO041530 A. (2.) ACUTE TOXICITY PASS/FAIL LIMIT (QUARTERLY) [15A NCAC 02B .0200 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 February, May, August and November. 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. Should any single quarterly monitoring indicate a failure to meet specified limits, then monthly monitoring will begin immediately until such time that a single test is passed. Upon passing, this monthly test requirement will revert to quarterly in the months specified above. 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 penod 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 chlonne 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 frorrl the facility dunng 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 momtonng is required, then monthly monitoring will begin immediately until such time that a single test is passed. Upon passing, this monthly test requirement will revert to quarterly in the months specified above. Assessment of toxicity compliance is based on the toxicity testing quarter, which is the three month time interval that begins on the first day of the month in which toxicity testing is required by this permit and continues until the final day of the third month Should any test data from either these monitonng 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 appropnate 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 monitonng. Page 4 of 7