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Permit No. OK0040461Page 1 of Part IDraft of March 18, 2020AUTHORIZATION TO DISCHARGE UNDER THEOKLAHOMA POLLUTANT DISCHARGE ELIMINATION SYSTEMPERMIT NUMBER: OK0040461ID NUMBER: S21325PART IIn compliance with the Oklahoma Pollutant Discharge Elimination System Act (OPDES Act), Title 27AO.S. § 2-6-201 et seq., and the rules of the State of Oklahoma Department of Environmental Quality (DEQ)adopted thereunder {See OAC 252:606}; the Federal Clean Water Act, Public Law 95-217 (33 U.S.C. 1251et seq.), Section 402; and NPDES Regulations (40 CFR Parts 122, 124, and 403),Skiatook Wastewater Treatment Plant – WestSkiatook, Town ofP.O. Box 399Skiatook, OK 74070is hereby authorized to discharge treated wastewater from a facility located at approximatelySW ¼, NE ¼, Section 33,Township 22 North, Range 12 East, IM,Osage County, Oklahomaor at 2880 West 133rd Street North, Skiatook, OK 74070to receiving waters: Hominy Creek at the point located at approximatelyLatitude: 36o 20' 29.510" N [GPS: NAD 1983 CONUS]Longitude: 96o 01' 19.072" W [GPS: NAD 1983 CONUS]Planning Segment No. 121300 (Water Body I.D. No. 121300040010 00)in accordance with effluent limitations, monitoring requirements and other conditions set forth in Parts I, II,III, and IV hereof.This permit replaces and supersedes the previous permit issued on April 21, 2015.The issuance date of this permit is Month Date, Year.This permit shall become effective Month Date, Year.This permit and authorization to discharge shall expire at midnight Month Date, Year.For the Oklahoma Department of Environmental Quality:Michael B. Moe, P.E., ManagerMunicipal Discharge and Stormwater Permit SectionWater Quality DivisionShellie R. Chard, DirectorWater Quality DivisionSkiatook Wastewater Treatment Plant –West

Permit No. OK0040461Page 2 of Part IA. Effluent Limitations and Monitoring Requirements (Outfall 001)1. Effluent LimitationsDuring the period beginning the effective date and lasting through date of expiration the permittee isauthorized to discharge treated wastewater in accordance with the following limitations:MassEffluent CharacteristicsFlow (mgd)[ STORET: 50050]CarbonaceousApr – MayBiochemicalOxygen Demand - Jun – Oct5 Day (CBOD5)[STORET: 80082] Nov – MarTotal Suspended Solids (TSS)[STORET: 00530]Ammonia – as N[STORET: 00610]Dissolved Oxygen(DO) [STORET:00300]E. Coli a[STORET: 51040]abcdDischarge LimitationsConcentration(lbs/day, unlessotherwisespecified)Monitoring Requirements(mg/l, unless otherwise 5.022.5---291.925.037.5---350.330.045.0---Apr – MayJun – OctNov – MarApr – MayJun – OctNov – Mar93.493.4140.1-------May– Sep---Oct – Apr---8.012.0--8.012.0--12.018.0--6.0 mg/l MINIMUM--5.0 mg/l MINIMUM--2.0 mg/l MINIMUM--126--406(geo. mean)630--2,030(geo. mean)Instantaneous Maximum:No Measurable bMeasurementFrequencySampleTypeDailyTotalized1 per Week6-hourcomposite1 per Week6-hourcomposite1 per Week6-hourcompositeDailyGrab2 per WeekGrab1 per WeekGrabTotal Residual Chlorine d--DailyGrab[STORET: 50060]pH (standard unit)--6.5 – 9.0DailyGrab[STORET: 00400]E. coli shall be reported in CFU/100 ml.No measurable is defined as less than 0.1 mg/l.Total coliform is measured in colonies/100 ml.If no chlorine is used for an entire reporting period, the permittee shall report a value of “zero” for the dailymaximum and enter “No chlorine used this reporting period” in the comments section on the DMR for thatreporting period in lieu of the indicated testing. For any week in which chlorine is used, the indicated testing shallbe done until the chlorine is no longer in use and at least one subsequent test verifies that the effluent meets thetotal residual chlorine limit.Other Year Round Requirements There shall be no discharge of floating solids or visible foam in other than trace amounts. There shall be no discharge of a visible sheen of oil or globules of oil or grease on or in thewater. Oil and grease shall not be present in quantities that adhere to stream banks and coatbottoms of water courses or which cause deleterious effects to the biota.Skiatook Wastewater Treatment Plant –West

Permit No. OK0040461Page 3 of Part I Samples taken in compliance with permit limits and monitoring requirements shall be takenat the end of the cascade aerator. All monitoring and reporting requirements shall also be in compliance with Part III of thispermit.2. Whole Effluent Toxicity Reporting and Monitoring RequirementsDuring the period beginning the effective date of the permit and lasting through the expiration date,the permittee is authorized to discharge from Outfall TX1 (functionally identical to Outfall 001).Such discharges shall be limited and monitored by the permittee as specified below.a. Whole effluent toxicity reporting and monitoring requirements – During the period beginningthe date of commencement of discharge from the new SBR plant and lasting through theexpiration date, the permittee is authorized to discharge from Outfall TX1 (functionally identicalto Outfall 001). The discharge consists of domestic sewage. Such discharge shall be limited andmonitored by the permittee as specified below.The permittee is encouraged to perform required biomonitoring activities as early in thereporting period as is practical to ensure sufficient time remains in the reporting period shouldretests/repeat tests be necessary.All laboratory analyses for the biomonitoring parameters specified in this permit must beperformed by a laboratory certified by the Oklahoma Department of Environmental Quality forthose parameters.Whole Effluent Toxicity Reporting and Monitoring Requirements(Outfall TX1)Reporting/MonitoringRequirements aEffluent CharacteristicCriticalDilution dRetestingRoutine TestingTestabDaphnia pulex,48-houracute LC50 staticrenewal, freshwaterPimephales promelas(Fathead minnow), 48hour acute LC50 staticrenewal, freshwaterRetest #1 [22415] bRetest #2 [22416]b100%100%Parameter48-hourMinPass/Fail Survival [TIM3D]ReportLC50 Effluent Conc [TAM3D]Report% Mortality at 100% Effluent[TJM3D]ReportPass/Fail Survival [TIM6C]ReportLC50 Effluent Conc [TAM6C]Report% Mortality at 100% ampleType1/quarter e24-hr comp1/quarter e24-hr compAsRequired c24-hr compSee Part II, Section E, Whole Effluent Toxicity Testing, for additional monitoring and reporting conditions.Applies to either or both test species according to results of test failure triggering monthly retests.Skiatook Wastewater Treatment Plant –West

Permit No. OK0040461Page 4 of Part IcdeMonthly retesting required only if routine test for reporting period (for either species) fails. Fill out ONLY thesetwo retest parameters on the retest DMRs, do not change the original results, and put the correct submission date inthe lower right hand corner of the DMR.All acute tests shall use the dilution series in Part II, Section E, Item 1.Results of retests conducted pursuant to prior test failure shall not be substituted on DMRs in lieu of routine testresults (see Part II, Section E, Item 2.a).D. pulex whole effluent toxicity reporting and monitoring requirements apply beginning, and the first reporting period is to .P. promelas (Fathead minnow) whole effluent toxicity reporting and monitoring requirementsapply beginning , and the first reporting period is to.WET testing summary reports: Reports of all WET testing initiated, regardless of whether suchtests are carried to completion, shall follow the requirements of Part II, Section E, Item 4.b. Concurrent testing provision for acute WET testing – Concurrent analyses of ammonia and pHare required for each individual effluent sample collected for acute WET testing or retesting ofthe Fathead minnow species. Reporting of concurrent testing results shall be in accordance withthe following requirements. Results shall also be submitted in or concurrently with each WETtest report.Concurrent Effluent Testing for Acute WET Tests – Reporting RequirementsOutfall TX1Effluent CharacteristicAmmonia, (NH3-N) (mg/l) a, b[STORET tReportReportMonitoring 24 hr comp bMeasured in each compositeReportN/AReport1/quarter effluent sample, including staticrenewals, just prior to first use bReport only those effluent samples collected for WET testing of the Fathead minnow species.pH (std units) a, b[STORET 00400]abSamples collected for WET testing purposes, including static renewals, shall be of sufficient volume to allowfor the required concurrent analyses in addition to the WET testing itself.Two sets of samples for concurrent analyses are required for ammonia and pH:Samples sent directly to a WET testing laboratory shall not undergo any preservation other than refrigeration tomaintain a temperature at or below 6º C but not frozen prior to arrival and processing at the WETtesting laboratory. These results may be used in the table above.A second concurrent analysis is required for the sample that is sent to the WET testing laboratory and for the tableabove. Just prior to first use of each composite sample for WET testing purposes, the biomonitoring laboratoryshall take an adequately-sized portion of each composite sample, acidify it in accordance with preservationrequirements in 40 CFR 136, and have it analyzed for ammonia (NH3-N) at a state certified laboratory. The pHmeasurement required for the table above must be taken just prior to the acidification step. These pH and ammoniareadings should NOT be included in the results for Outfall 001.Concurrent ammonia analyses must be performed on composite samples that are properly preserved and delivereddirectly to a state certified analytical laboratory. These results shall be included in the results for Outfall 001.Skiatook Wastewater Treatment Plant –West

Permit No. OK0040461Page 5 of Part Ic. Sampling location – Samples taken in compliance with the monitoring requirements specifiedabove for Outfall TX1 shall be taken at the following location: at the same location as for Outfall001.B. Compliance ScheduleThe permittee shall achieve compliance with the final effluent limitations in accordance with thefollowing schedule:ActionCease discharge from the Central plant (OK0028118), submit Affidavit of NoDischarge, and complete closure of the lagoon system.Achieve full compliance with final limits for the parameters in Part I.A.1 of thepermit.Collect influent and effluent samples in accordance with Table 1 and Attachments2 and 3 of application Form 2M1, and submit analytical results.Compliance Date6 months after effective date of permit6 months after effective date of permit9 months after effective date of permitC. Sanitary Sewer OverflowsAny bypass in the collection system [sanitary sewer overflow (SSO)] shall be reported in accordancewith Permit Part III.B.6.D. Reporting of Monitoring ResultsMonitoring results shall be reported in accordance with the provisions of Part III.B.5 of the permit.Monitoring results obtained during the previous month shall be summarized and electronically reportedon an electronic Discharge Monitoring Report (eDMR) form due to the Oklahoma Department ofEnvironmental Quality, Water Quality Division, Wastewater Compliance Tracking Section no later thanthe 15th day of the month following the completed monthly test. If no discharge occurs during thereporting period, an eDMR form stating "No Discharge" shall be electronically submitted according tothe above schedule. Instructions on how to register as a Preparer or Signatory for eDMRs, as well as howto prepare and submit eDMRs, can be found on DEQ’s website at ronic-reporting/. Assistance is also available by contacting DEQ at (405) 702-8100 or [email protected] first report is due on the 15th of MONTH, 2020. Skiatook Wastewater Treatment Plant –West

Permit No. OK0040461Permit Part II – Page 1PERMIT PART II - OTHER PERMIT REQUIREMENTSA. CONTRIBUTING INDUSTRIES AND PRETREATMENT REQUIREMENTS1. The following pollutants shall not be introduced into a Publicly Owned Treatment Works (POTW)facility, defined in 40 CFR 403.3(o) “as any devices and systems used in storage, treatment,recycling and reclamation of municipal sewage and industrial wastes of a liquid nature. It alsoincludes sewers, pipes and other conveyances only if they convey wastewater to a POTW TreatmentPlant. The term also means the municipality as defined in Section 502(4) of the Act, which hasjurisdiction over the Indirect Discharges to and from such treatment works.”a. Pollutants which create a fire or explosion hazard in the POTW facility, including, but notlimited to, wastestreams with a closed cup flashpoint of less than 60 C (140 F) using the testmethods specified in 40 CFR 261.21;b. Pollutants which will cause corrosive structural damage to the POTW, but in no case dischargeswith pH lower than 5.0, unless the works are specifically designed to accommodate suchdischarges;c. Solid or viscous pollutants in amounts which will cause obstruction to the flow in the POTW,resulting in interference;d. Any pollutant, including oxygen demanding pollutants (e.g., BOD), released in a discharge at aflow rate and/or pollutant concentration which will cause interference with the POTW;e. Heat in amounts which will inhibit biological activity in the POTW resulting in interference butin no case heat in such quantities that the temperature at the POTW treatment plant exceeds 40 C(104 F) unless the Approval Authority, upon request of the POTW, approves alternatetemperature limits;f.Petroleum oil, non-biodegradable cutting oil, or products of mineral oil origin in amounts thatwill cause interference or pass through;g. Pollutants which result in the presence of toxic gases, vapors, or fumes within the POTW in aquantity that may cause acute worker health and safety problems; andh. Any trucked or hauled pollutants, except at discharge points designated by the POTW.2. The permittee shall require any indirect discharger to the treatment works to comply with thereporting requirements of Sections 204(b), 307, and 308 of the Act, including any requirementsestablished under 40 CFR Part 403.3. The permittee shall provide adequate notice of the following:a. Any new introduction of pollutants into the treatment works from an indirect discharger whichwould be subject to Sections 301 and 306 of the Act and/or Sections 40 CFR 405-499 if it weredirectly discharging those pollutants; andb. Any substantial change in the volume or character of pollutants being introduced into thetreatment works by a source introducing pollutants into the treatment works at the time ofissuance of the permit.Skiatook Wastewater Treatment Plant –West

Permit No. OK0040461Permit Part II – Page 2c. Any notice shall include information on (i) the quality and quantity of effluent to be introducedinto the treatment works, and (ii) any anticipated impact of the change on the quality or quantityof effluent to be discharged from the POTW.B. REOPENER CLAUSEThis permit may be reopened for modification or revocation and reissuance to require additionalmonitoring and/or effluent limitations where actual or potential exceedances of State water qualitycriteria are determined to be the result of the permittee’s discharge to the receiving water(s), or a revisedTotal Maximum Daily Load is established for the receiving water(s), or when required as technologyadvances. Modification or revocation and reissuance of the permit shall follow regulations listed at 40CFR 124.5C. BIOSOLIDS/SEWAGE SLUDGE REQUIREMENTSThe permittee will be required to prepare and obtain approval of a biosolids/sewage sludge managementplan prior to removing biosolids/sewage sludge from the facility. The plan shall comply with the Federalregulations for landfills and land application of biosolids/sewage sludge, and solid waste disposalestablished at 40 CFR Part 257, 503, and the DEQ rules governing Sludge Management (OAC 252:515and OAC 252:606) as applicable.This is a new discharge permit, therefore any sludge produced prior to obtaining a sludge managementplan will stay onsite until a sludge management plan is approved. New applicants must be in accordancewith OAC 252:606-8.The permittee is required to maintain all records relevant to biosolids/sewage sludge disposal for the lifeof the permit. These records shall be made available to the ODEQ upon request.The permittee shall give 120 days prior notice to DEQ of any change planned in the biosolids/sewagesludge disposal practice.D. POLLUTION PREVENTION REQUIREMENTS1. The permittee shall institute a program within 12 months of the effective date of the permit (orcontinue an existing program) directed towards optimizing the efficiency and extending the usefullife of the facility. The permittee shall consider the following items in the program:a.b.c.d.e.f.g.h.i.The influent loadings, flow and design capacity;The effluent quality and plant performance;The age and expected life of the wastewater treatment facility's equipment;Bypasses and overflows of the tributary sewerage system and treatment works;New developments at the facility;Operator certification and training plans and status;The financial status of the facility;Preventative maintenance programs and equipment conditions; andAn overall evaluation of conditions at the facility.2. The permittee shall prepare the following information on the biosolids/sewage sludge generatedby the facility:a. An annual quantitative tabulation of the ultimate disposition of all biosolids/sewage sludge(including, but not limited to, the amount beneficially reused, landfilled, and incinerated).Skiatook Wastewater Treatment Plant –West

Permit No. OK0040461Permit Part II – Page 3b. An assessment of technological processes and an economic analysis evaluating the potential forbeneficial reuse of all biosolids/sewage sludge not currently beneficially reused including alisting of any steps which would be required to achieve the biosolids/sewage sludge qualitynecessary to beneficially reuse the biosolids/sewage sludge.c. A description of, including the expected results and the anticipated timing for, all projects inprocess, in planning and/or being considered which are directed towards additional beneficialreuse of biosolids/sewage sludge.d. An analysis of one composite sample of the biosolids/sewage sludge collected prior to ultimatere-use or disposal shall be performed for the pollutants listed in Part IV, Element 1, Section III,Table 3.e. A listing of the specific steps (controls/changes) which would be necessary to achieve andsustain the quality of the biosolids/sewage sludge so that the pollutant concentrations in thebiosolids/sewage sludge fall below the pollutant concentration criteria listed in Part IV, Element1, Section III, Table 3.f.A listing of, and the anticipated timing for, all projects in process, in planning, and/or beingconsidered which are directed towards meeting the biosolids/sewage sludge quality referenced in(e) above.The permittee shall certify in writing, within three years of the effective date of the permit, that allpertinent information is available. This certification shall be submitted to:Oklahoma Department of Environmental QualityWater Quality DivisionMunicipal Permits SectionP. O. Box 1677707 North Robinson StreetOklahoma City, Oklahoma 73101-1677E. WHOLE EFFLUENT TOXICITY TESTING1. Scope and Methodologya. The permittee shall test the effluent for toxicity in accordance with the provisions in thissection, which apply individually and separately to the outfalls listed below. No samples orportions of samples from one outfall may be composited with samples or portions of samplesfrom another outfall. The permittee shall biomonitor for Daphnia pulex and Pimephalespromelas in accordance with the WET testing frequencies prescribed in Part I.The permittee is encouraged to perform required biomonitoring activities as early in thereporting period as is practical to ensure sufficient time remains in the reporting periodshould retests/repeat tests be necessary.All laboratory analyses for the biomonitoring parameters specified in this permit must beperformed by a laboratory certified by the Oklahoma Department of Environmental Qualityfor those parameters.Skiatook Wastewater Treatment Plant –West

Permit No. OK0040461Permit Part II – Page 4Intervals between test initiation dates shall be a function of the required testing frequency, asfollows: Monthly:Quarterly:Semi-annually:No less than 20 days and no more than 40 days.No less than 2 months and no more than 4 months.No less than 4 months and no more than 8 months.APPLICABLE TO OUTFALL(S):001REPORTED ON DMR AS OUTFALL(S):TX1CRITICAL DILITION:100%EFFLUENT DILUTION SERIES (ALL TESTS):32%, 42%, 56%, 75%, 100%SAMPLE TYPE:Defined at Part ITEST SPECIES/METHODS:40 CFR 136, except for changesrequired by EPA, Region 6.Daphnia pulex acute static renewal 48-hour definitive toxicity test, Method 2021.0, EPA821-R-02-012 (October 2002), or latest update thereof. A minimum of five (5) replicateswith eight (8) organisms per replicate must be used in the control and in each effluentdilution of this test.Pimephales promelas (Fathead minnow) acute static renewal 48-hour definitive toxicity test,Method 2000.0, EPA-821-R-02-012 (October 2002), or latest update thereof. A minimum offive (5) replicates with eight (8) organisms per replicate must be used in the control and ineach effluent dilution of this test.b. Acute test failure –Acute test failure (LC50 test) is defined as 50% or more lethality (toxicity)at 48 hours to test organisms at any effluent concentration. The 48-hour LC50 effluent valuemust be 100% to indicate a passing test. Any 48-hour LC50 effluent value of 100% or less(or equivalently, a survival value of less than 50.1% in any test dilution) will constitute a testfailure.c. Reopener clause – This permit may be reopened to require whole effluent toxicity limits,chemical specific effluent limits, additional testing, and/or other appropriate actions toaddress toxicity.2. Testing Requirements due to Test FailureUpon becoming aware of the failure of any test, the permittee shall immediately notify the DEQWater Quality Division biomonitoring coordinator, and shall provide written notification within5 working days, of the test failure with a summary of the results of, and any other pertinentcircumstances associated with, the failed test.a. Whenever there is a test failure for Daphnia pulex and/or Pimephales promelas duringroutine testing, the frequency of testing for Daphnia pulex and/or Pimephales promelas shallautomatically increase to, or continue at, as appropriate, the WET testing frequencyprescribed in Part I for the remaining life of the permit. In addition, two (2) additionalSkiatook Wastewater Treatment Plant –West

Permit No. OK0040461Permit Part II – Page 5monthly tests (retests) of Daphnia pulex and/or Pimephales promelas are required. The twoadditional tests shall be conducted monthly during the next two consecutive months. Thepermittee shall not substitute either of the two additional tests for routine toxicity testing. Afull laboratory report for the failed routine test and both additional tests, if required, shall beprepared and submitted to DEQ in accordance with procedures outlined in Item 4 of thissection.b. Persistent toxicity – If either of the two additional tests results in an LC50 value less than orequal to 100%, persistent toxicity is exhibited. Then the permittee shall initiate a ToxicityReduction Evaluation (TRE) as specified in Item 6 of this section. The TRE initiation datewill be the test completion date of the first failed retest. The permittee may request atemporary exemption to this TRE-triggering criterion only if the permittee is under acompliance schedule defined in an OPDES permit or an enforcement order to effect aquatictoxicity reduction measures.c. Intermittent toxicity – If both additional tests result in an LC50 value of greater than 100%,persistent toxicity is not exhibited. However, if any routine test failure occurs within 18months of a prior test failure, intermittent toxicity is exhibited, and the permittee may berequired by DEQ to initiate a TRE, as described in Item 6 of this section, based on theseverity and pattern of such toxic effect over time.d. Suspension of Retesting Requirement During TRE - Retesting requirements in Item 2.a aretemporarily suspended upon submittal of a TRE Action Plan. Such suspension of retestingrequirements applies only to the species under evaluation by a TRE and only to the periodduring which a TRE is being performed.3. Required Toxicity Testing Conditionsa. Test acceptance – The permittee shall repeat a test, including the control and all effluentdilutions, if the procedures and quality assurance requirements defined in the test methods orin this permit are not satisfied, including the following additional criteria:(1) The toxicity test control (0% effluent) must have survival equal to or greater than 90%.(2) The percent coefficient of variation between replicates shall be 40% or less in thecontrol (0% effluent) for the Daphnia pulex and Fathead minnow survival tests.(3) The percent coefficient of variation between replicates shall be 40% or less in thecritical dilution, unless significant toxicity is exhibited in the Daphnia pulex andFathead minnow survival tests.(4) As documented at test termination, no more than forty (40) percent of the daphnid testorganisms in any replicate of any effluent dilution or in any replicate of the control (0%effluent) shall be male.If the above criteria or criteria listed in Item 1.a are not met the test will be consideredinvalid. Test failure may not be construed or reported as invalid due to a coefficient ofvariation value for toxicity of greater than 40% for replicates tested at the critical dilution. Arepeat test shall be conducted and the biomonitoring enforcement coordinator notified,within the reporting period of any test determined to be invalid.b. The permittee shall follow the requirements listed below in determining success or failure ofa WET test:Skiatook Wastewater Treatment Plant –West

Permit No. OK0040461Permit Part II – Page 6The statistical analyses in the Daphnia pulex and the Fathead minnow survival tests, used todetermine the LC50 shall be in accordance with the methods described in EPA-821-R-02012, or the most recent update thereof.c. The permittee shall use dilution water that meets the following standards:(1) Dilution water used in the toxicity tests will be receiving water collected as close to thepoint of discharge as possible but unaffected by the discharge. In OAC 252:690-3-36,for discharges to a receiving stream classified as intermittent or to a receiving streamwith no flow due to zero flow, the permittee shall substitute synthetic dilution water ofsimilar pH, hardness and alkalinity to the closest downstream perennial water where thetoxicity test is conducted. In the event that the receiving stream has sufficient flow for asample to be collected, the facility will return to receiving stream water instead ofsynthetic.(2) If the receiving water is unsatisfactory as a result of instream toxicity (fails to meet thetest acceptance criteria in Item 3.a), the permittee must submit the test results exhibitingreceiving water toxicity with the full test report required in Item 4 below and maythereafter substitute synthetic dilution water for the receiving water in all subsequenttests, provided the unacceptable receiving water test met the following stipulations:(a) a synthetic dilution water control which fulfills the test acceptance requirements ofItem 3.a was run concurrently with the receiving water control;(b) the test indicating receiving water toxicity was carried out to completion (i.e., 48hours);(c) the synthetic dilution water had a pH, hardness and alkalinity similar to that of thereceiving water or closest downstream perennial water not adversely affected by thedischarge, provided the magnitude of these parameters will not cause toxicity in thesynthetic dilution water; and(d) the receiving water test must be conducted at the start of each permitting cycle.d. The permittee shall collect samples that are representative of their effluent by following thecriteria listed below:(1) Unless grab sampling is specifically authorized in Part I of the permit, the permitteeshall collect two flow-weighted 24-hour composite samples representative of the flowsduring normal operation from the outfall(s) listed at Item 1.a above. If grab sampling isauthorized, all the requirements listed below for composite sampling also pertain tograb sampling. In such cases, collection of the grab sample is considered equivalent tocollection of the last portion of a composite sample. Unless otherwise specified in Part Iof the permit, a 24-hour composite sample consists of a minimum of 12 effluentportions collected at equal time intervals representative of a 24-hour operating day andcombined proportional to flow, or a sample continuously collected proportional to flowover a 24-hour operating day.(2) The permittee must collect the composite samples so that the maximum holding timefor any effluent sample shall not exceed 36 hours. The permittee must initiate thetoxicity test within 36 hours after the collection of the last portion of the first compositesample. The first composite sample shall be used to initiate each test. The secondSkiatook Wastewater Treatment Plant –West

Permit No. OK0040461Permit Part II – Page 7composite sample shall be used for 24-hour static renewal of each dilutionconcentration for each test. Samples shall be chilled to maintain a temperature at orbelow 6 C but not frozen during collection, shipping, and/or storage

Skiatook Wastewater Treatment Plant - West . Skiatook, Town of . P.O. Box 399 . Skiatook, OK 74070 . is hereby authorized to discharge treated wastewater from a facility located at approximately . SW ¼, NE ¼, Section 33, Township 22 North, Range 12 East, IM, Osage County, Oklahoma . or at 2880 West 133rd Street North, Skiatook, OK 74070