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HomeMy WebLinkAboutDEQ Permit LetterMontana Department of EMRONMENTAL QUALITY Brian Schweitzer, Governor P.O. Box 200901 • Helena, MT 59620-0901 May 20, 2009 U It Kenneth E. Olson, Jr., Mayor MAY 2 1 2009 City of Laurel P.O. Box 10 CITY 4F LAUREL Laurel, MT 59044 RE: Notice of Final Decision, Montana Pollutant Discharge Elimination System (MPDES) Permit No.: MT0020311 Dear Mr. Olson: In accordance with the Administrative Rules of Montana (ARM) 17.30.1377, enclosed is the Response to Comments and a copy of the proposed permit for the City of Laurel wastewater treatment plant. The permit is issued by the Department under the authority of 75-5-402, Montana Code Annotated (MCA) and Sections 402 and 303 of the federal Clean Water Act. The Response to Comments addresses issues that were identified during the public comment period. The public comment period closed May 5, 2009. The following changes were made in the proposed permit in response to comments received during the public comment period: 1. The implementation date for new E.coli and Total Residual Chlorine limits is changed to June 1, 2013. 2. The units of measurement for total nitrogen and total phosphorus on page 5 and 6 have been changed to lb/day. 3. Nutrient sampling requirements for ammonia, nitrate + nitrite, Total Kjeldahl Nitrogen, total nitrogen and total phosphorus in the Monitoring Requirements Table on page 8 are changed to 2/Month. 4. Sampling requirements for metals and hardness in the Monitoring Requirements Table on page 9 are reduced to twice a year for two years (2010 and 2011) by placing footnote 5 on metals and hardness in the table. In accordance with ARM 17.30.1378, the Department's final decision to issue the permit is effective 30 days after service of this notice. Under ARM 17.30.1370, the applicant may appeal this decision within the 30 day period in accordance with 75-5-403 and 75- 5-611, MCA. Pursuant to 40 CFR 122.44, the Regional Administrator may object to or make recommendations to the proposed permit. mt.gov Enforcement Division • Permitting & Compliance Division • Planning, Prevention & Assistance Division • Remediotion Division Kenneth E. Olson, Jr., Mayor May 20, 2009 J Page 2 of 2 A copy of the permit should be made available to the person in charge of the operation of the wastewater treatment facility so that person is aware of the requirements in the permit. Please take note of any revised monitoring requirements specified in Part I of the permit. The preprinted Discharge Monitoring Report (DMR) forms will be sent soon. Please contact the permit writer, John Wadhams, at 406-444-2783 if you have any questions. Sincerely, Jenny Chambers, Chief Water Protection Bureau Permitting and Compliance Division jcham_bersCa?mt.eov Enclosures: Permit No.: MT0020311 Response to Comments 0 cc: Rosemary Rowe, EPA Bill Sheridan, Chief Administrative Officer City of Laurel P.O. Box 10 Laurel, MT 59044 Bob Mann, Chief Operator City of Laurel P.O. Box 10 Laurel, MT 59044 Scott Murphy Morrison-Majerle, Inc. 1 Engineering Place Helena, MT 59602 File 0 Response to Comments City of Laurel Wastewater Treatment Plant Montana Pollutant Discharge Elimination System (MPDES) Permit MT0020311 On April 3, 2009 the Department issued public notice MT-09-09 stating its intent to issue a MPDES permit to the City of Laurel for the City of Laurel wastewater treatment plant. A copy of the public notice, draft permit and Statement of Basis (SOB) was provided to the City of Laurel during the public comment period and these documents were also made available to other interested parties. The public comment period closed May 5, 2009. Comments on the MPDES permit were received from the City of Laurel. Below is the Department's response to these comments. 1. Comment: SOB, Table 1, page 5; Requested Correction - To be accurate, the WWTP was not modified in 2006. The 2006 project was completed in the collection system only. Response: Comment noted. To make the SOB more accurate, the 2006 date will be removed from Table 1. 2. Comment: SOB, page 11 and Permit, page 4; Mixing Zone - MDEQ is no longer granting a mixing zone for the. effluent outfall due to its location on a backwater of the River. Based on current state law, it is the City's understanding that it may request a mixing zone in the future, if it is determined this is prudent. The City further understands that a mixing zone study would have to be performed as part of such a request. Response: Based on Administrative Rule of Montana (ARM) 17.30.515(2) which states "A person applying to the Department for a mixing zone must indicated the type of mixing zone applied for and supply sufficient detail for the Department to make a determination regarding the authorization of the mixing zone under the rules of this subchapter", the City is correct that it may request a mixing zone in the future. The City is also correct that a mixing zone study, typically provides the Department with the necessary information it needs to evaluate the requested mixing zone. The City should also understand there are other factors, such as. biologically important areas, proximity to drinking water intake structures, toxicity of effluent discharged, and other factors listed in ARM 17.30.506 that the Department must consider in determining whether a mixing zone should be applied to a discharge. The City should consult the Mixing Zone Rules at ARM 17.30.501-518 and with the Department before applying for a mixing zone in the future. I Comment: SOB, page 13 and 18; Permit page 6; schedule for E.coli and Total Residual Chlorine Limit; Requested. Modification - MDEQ is proposing that the updated limits be effective June 1, 2011, two years from now. These limits necessitate the implementation of the UV disinfection facilities recommended in the 2009 PER Update. The City requests that the implementation date for the E.coli and Total Residual Chlorine Limit be modified to June 1, 2013, for the reasons explained below. • ,c 4. The City of Laurel has embarked upon a $6.1 million wastewater improvements project, described as "Phase 2A" in the 2009 PER Update that will be complete on about June 1, 2011. This project includes, as its major elements, rehabilitation of two lift stations in the collection system, rehabilitation of the WWTP headworks, and the addition of a new activated sludge secondary treatment system to supplement the aging RBC secondary treatment facility. While a primary reason for this project is replacement of aging equipment and unit processes, a secondary result is that the new activated sludge facility will begin to address the ammonia and nutrient reduction needs that the SOB indicates will be required in the next permit cycle. In order to afford these 2A facilities, the City has successfully obtained grant funding from the TSEP program and through the SRF ARRA stimulus funds. Even with these successes, the City is in its third year of 19 percent/year wastewater rate hikes. Based on this investment, the City is clearly committed to improving the WWTP and water quality in the Yellowstone River. By modifying the E.coli and Total Residual Chlorine Limits implementation as requested, the City will have the opportunity to apply to the TSEP program in May 2010 for a grant associated with the Phase 2B (UV Disinfection) and 2C projects (as described in the 2009 PER Update). This process would allow the City to initiate construction of these improvements in 2012 and be ready for full compliance-with the noted limits by June 1, 2013. Response: Based on the conference call between the City and Department on Thursday, April 30, 2009 and the reasons stated above, the Department agrees that the implementation date for E.coli and Total Residual Chlorine limits should be changed to June 1, 2013. Appropriate changes will be made in the permit. 4. Comment: Permit, Effluent Limitations Tables, page 5 and 6; Correction - We believe that the units for Total Nitrogen and Total Phosphorus are incorrectly stated as "mg/L" and would be correctly changed to "lb/day". Response: Comment noted. Changes made in the permit. 5. Comment: SOB, page 19; Permit, page 8; Monitoring Requirements; Requested Modification - The nutrient sampling requirements listed are a mixture of 1 /week and 1 /month requirements. We would request that total ammonia, nitrite + nitrate, TKN, TN and TP be standardized as a 2x/month parameters. This would achieve the MDEQ's goals of additional information in support of future permit preparation and River load computation, and result in better standardization of sampling and procedures for our staff. Response: The Department agrees with this comment. Nutrient sampling requirements in the Monitoring Requirements table on page 8 of the permit for ammonia, nitrate + nitrite, Total Kjeldahl Nitrogen, total nitrogen and total phosphorus will be changed to 2/Month. 6. Comment: SOB, page 20; Permit, page 9, Monitoring Requirements; Requested Modification - The new sampling required for the parameters in this table represent a significant increase in analytical costs for the City. While we understand and recognize the importance of establishing the discharge concentration for these parameters, we request that the MDEQ reduce 2 .1. the frequency of sampling for parameters Antimony through Hardness in one of two ways: 1) reduce the frequency to 1 /year, or 2) incorporate. a limit on samples similar to footnote 5 (applicable to the volatile and semi-volatile compounds). Response: The Department has reduced the sampling requirements for metals and hardness from twice a year for 5 years to twice a year for two years (2010 and 2011) by placing footnote 5 on metals and hardness in the table. Therefore, all parameters listed on the Monitoring Requirements Table on page 9 of the permit will be required to be collected and analyzed the first and third quarters of 2010 and 201 L 7. Comment: SOB, page 16; Permit, page 10, WET Testing; Requested Modification - The City has been regularly performing acute toxicity WET testing, beginning in 2000. As documented in the SOB, the City has consistently passed these tests. The draft proposed WET testing regimen includes testing for both water flea and fathead minnow in each quarter. We request that the City be allowed to test alternate species each quarter, consistent with the current permit, in recognition of the long-standing compliance (passing) with WET testing requirements and the cost associated with the dual species testing. Response: In light of the proposed construction and potential disruption of treatment processes this permit cycle and the fact that three industrial dischargers contribute to the wastewater influent at the wastewater plant, WET testing using both species each quarter will remain in this permit. A reduction in WET testing will be evaluated next permit cycle. 8. Comment: SOB, page 15, Toxic Pollutants; Requested Addition - The City requests that MDEQ include further explanation regarding the need and rational for the additional metals and volatiles sampling. The new testing will result in additional costs to the City and background on the requirements will assist the City in explaining these costs to the rate payers and industrial users. Response: In the response to Comment 6, metals and volatiles sample requirements have been reduced as requested by the City. No metals or volatiles data has ever been collected from the City of Laurel's discharge to the Yellowstone River. To properly characterize the discharge, these potential pollutants must be evaluated. Furthermore, three industries discharge to,the City of Laurel wastewater treatment plant: Montana Rail Link (MRL), Cenex Harvest States (Cenex) Refinery and Woods Power Grip. Potential pollutants from these industries not only pose a potential threat to the environment but may cause increased corrosion, upsets or other problems in the City's treatment plant and collection system. • Minor POTW Permit No.: MT 0020311 MONTANA DEPARTMENT OF ENVIRONMENTAL QUALITY AUTHORIZATION TO DISCHARGE UNDER THE MONTANA POLLUTANT DISCHARGE ELIMINATION SYSTEM In compliance with Montana Water Quality Act, Title 75, Chapter 5, Montana Code Annotated (MCA) and the Federal Water Pollution Control Act (the "Clean Water Act"), 33 U.S.C. § 1251 et seq., City of Laurel is authorized to discharge from its Wastewater Plant located at 1508 Sewer Plant Road • to receiving waters named Yellowstone River, in accordance with discharge point(s), effluent limitations, monitoring requirements and other conditions set forth herein. Authorization for discharge is limited to those outfalls specifically listed in the permit. This permit shall become effective on July 1, 2009. This permit and the authorization to discharge shall expire at midnight on June 30, 2014. FOR THE MONTANA DEPARTMENT OF ENVIRONMENTAL QUALITY Jenny Ch ers, Chief Water Protection Bureau Permitting & Compliance Division Issuance Date: f' ,L. So,Ol!)? j • Page 2 of 29 Permit No.. MT 0020311 TABLE OF CONTENTS • Cover Sheet--Issuance and Expiration Dates 1. EFFLUENT LIMITATIONS, MONITORING REQUIREMENTS & OTHER CONDITIONS .................3 A. DESCRIPTION OF DISCHARGE POINTS AND MIXING ZONE ........................................................................... .. 3 B. EFFLUENT LIMITATIONS .............................................................................................................................. .. 3 C. MONITORING REQUIREMENTS ..................................................................................................................... .. 6 D. SPECIAL CONDITIONS .................................................................................................................................. 10 E. PRETREATMENT REQUIREMENTS ................................................................................................................. 10 H. MONITORING, RECORDING AND REPORTING REQUIREMENTS ................................................... 13 A. REPRESENTATIVE SAMPLING ....................................................................................................................... 13 B. MONITORING PROCEDURES ......................................................................................................................... 13 C. PENALTIES FOR TAMPERING ........................................................................................................................ 13 D. REPORTING OF MONITORING RESULTS ........................................................................................................ 13 E. COMPLIANCE SCHEDULES ........................................................................................................................... 14 F. ADDITIONAL MONITORING BY THE PERMITTEE ........................................................................................... 14 G. RECORDS CONTENTS ................................................................................................................................... 14 H. RETENTION OF RECORDS ............................................................................................................................. 14 I. TWENTY-FOUR HOUR NOTICE OF NONCOMPLIANCE REPORTING ................................................................ 15 1. OTHER NONCOMPLIANCE REPORTING ......................................................:................................................... 15 K. INSPECTION AND ENTRY .............................................................................................................................. 16 III. COMPLIANCE RESPONSIBILITIES ............................................................................................................17 A. DUTY TO COMPLY ....................................................................................................................................... 17 B. PENALTIES FOR VIOLATIONS OF PERMIT CONDITIONS ................................................................................. 17 C. NEED TO HALT OR REDUCE ACTIVITY NOT A DEFENSE ............................................................................... 17 D. DUTY TO MITIGATE ..................................................................................................................................... 17 E. PROPER OPERATION AND MAINTENANCE .................................................................................................... 17 F. REMOVED SUBSTANCES .............................................................................................................................. 18 G. BYPASS OF TREATMENT FACILITIES ............................................................................................................ 18 H. UPSET CONDITIONS ..................................................................................................................................... 19 • IV. GENERAL REQUIREMENTS .........................................................................................................................21 A. PLANNED CHANGES ............................. ..................................... ...................... ....... .. .................... . 21 B. ANTICIPATED NONCOMPLIANCE ................................................................................................................. 21 C. PERMIT ACTIONS ......................................................................................................................................... 21 D. DUTY TO REAPPLY ...................................................................................................................................... 21 E. DUTY TO PROVIDE INFORMATION ............................................................................................................... 21 F. OTHER INFORMATION ....................... ............................ .................... .......... ................................................ 21 G. SIGNATORY REQUIREMENTS ..................... H. PENALTIES FOR FALSIFICATION OF REPORTS .......... ..................................................................................... 23 1. AVAILABILITY OF REPORTS ......................................................................................................................... 23 1. OIL AND HAZARDOUS SUBSTANCE LIABILITY ........................................................................:.................... 23 K. PROPERTY OR WATER RIGHTS .................................................................................................................... 23 L. SEVERA13ILITY ............................................................................................................................................. 23 M. TRANSFERS ................................................................................................................................................. 23 N. FEES ............................................................................................................................................................ 24 0. REOPENER PROVISIONS ............................................................................................................................... 24 V. DEFINITIONS ................................................................................................................................................... 26 Part I Page 3 of 29 Permit No.: MT 0020311 I. EFFLUENT LIMITATIONS, MONITORING REQUIREMENTS & OTHER CONDITIONS A. Descri tion of Discharge Points and Mixing Zone The authorization to discharge provided under this permit is limited to those outfalls specially designated below as discharge locations. Discharges at any location not authorized under an MPDES permit is a violation of the Montana Water Quality Act and could subject the person(s) responsible for such discharge to penalties under the Act. Knowingly discharging from an unauthorized location or failing to report an unauthorized discharge within a reasonable time from first learning of an unauthorized discharge could subject such person to criminal penalties as provided under Section 75-5-632 of the Montana Water Quality Act. Outfall Descri Lion • 001 Location: At the end of the outfall pipe discharging into a side channel of the Yellowstone River (and small ditch entering the Yellowstone River) at 450 39'20" N latitude, 108° 43' 11" W longitude. Mixing Zone: The maximum extent of the chronic mixing zone in the named receiving waters is as follows: none The maximum extent of the acute mixing zone in the named receiving waters is as follows. none. Treatment Works: Rotating biological contactors. B. Effluent Limitations Outfall 001 Effective immediately and lasting through the term of the permit, the quality of effluent discharged through Outfall 001 shall, as a minimum, meet the limitations as set forth below: Part I Page 4 of 29 Permit No.: MT 0020311 1. Interim Effluent Limits (Effective on the permit issuance date) Effluent Limitations: Outfall 001 Average Average Maximum Parameter Units Monthly Weekly Daily Limit' Limit' Limit ` Biochemical Oxygen Demand (BOD5) mg/L 30 45 -- lb/day 220 330 -- Total Suspended Solids (TSS) mg/L 30 45 -- lb/day 220 330 -- Total Residual Chlorine (TRC) mg/L -- -- 0.5 E. cola Bacteria 2.3 cfu/100mL 34,020 74,340 -- Total Nitrogen as N lb/day 233 363 -- Total Phosphorus as P lb/day 47 73 -- Oil and grease mg/L -- -- 10 Footnotes: " 1. See Definition section at end of ermit f l i p or exp anat on of terms. 2. This limit applies during the period.April 1 through October 31. 1 Report Geometric Mean if more than one sample is collected in the reporting period. Effluent pH shall remain between 6.0 and 9.0. For compliance purposes, any single analysis and/or measurement beyond this limitation shall be considered a violation of the conditions of this permit. 85 Percent (%) Removal Requirement for 130135: The arithmetic mean of the BOD5 for effluent samples collected in a period of 30 consecutive days shall not exceed 15% of the arithmetic mean of the values for influent samples collected at approximately the same times during the same period (85%x-emoval). This is in addition to the concentration limitations on BOD5. 85 Percent (%) Removal Requirement for TSS: The arithmetic mean of the TSS for effluent samples collected in a period of 30 consecutive days shall not exceed 15% of the arithmetic mean of the values for influent samples collected at approximately the same times during the same period (85% removal). This is in addition to the concentration limitations on TSS. There shall be no discharge of floating solids or visible foam in other than trace amounts. There shall be no discharge which causes visible oil sheen to the receiving stream. Part I Page 5 of 29 Permit No.: MT 0020311 • ?J 2. Final Limits (Effective June 1, 2013) Effluent Limitations: Outfall 001 Parameter Units Average Monthly Limit' Average Weekly Limit' Maximum Daily Limit ' Biochemical Oxygen Demand mg/L 30 45 -- (BODO lb/day 220 330 -- Total Sus ended Solids (TSS) mg/L 30 45 -- p lb/day 220 330 E. soli Bacteria 2,4 cfu/100mL 126 252 E. cola Bacteria 3°4 cfu/100mL 630 1,260 -- Total Residual Chlorine (TRC) 5 mg/L 0.011 -- 0.019 Total Nitrogen as N lb/day 363 -- Total Phosphorus as P lb/day t47 73 -- Oil and grease mg/L, -_ 10 Footnotes: 1. See Definition section at end of permit for explanation of terms. 2. This limit applies during the period April 1 through October 31. 3. This limit applies during the period November 1 through March 31. 4. Report Geometric Mean if more than one sample is collected in the reporting period. 5. Not a licable if UV disinfection is operating and chlorine is not used for disinfection. Effluent pH shall remain between 6.0 and 9.0. For compliance purposes, any single analysis and/or measurement beyond this limitation shall be considered a violation of the conditions of this permit. 85 Percent (%) Removal Requirement for BOD5: The arithmetic mean of the BOD5 for effluent samples collected in a period of 30 consecutive days shall not exceed 15% of the arithmetic mean of the values for influent samples collected at approximately the same times during the same period (85% removal). This is in addition to the concentration limitations on BOD5. 85 Percent (%) Removal Requirement for TSS: The arithmetic mean of the TSS for effluent samples collected in a period of 30 consecutive days shall not exceed 15% of the arithmetic mean of the values for influent samples collected at approximately the same times during the same period (85% removal). This is in addition to the concentration limitations on TSS. • There shall be no discharge of floating solids or visible foam in other than trace amounts. There shall be no discharge which causes visible oil sheen in the receiving stream. Part I Page 6 of 29 Permit No.: MT 0020311 • C. Monitoring Requirements Outfall 001 .As a minimum, upon the effective date of this permit, the following constituents shall be monitored at the frequency and with the type of measurement indicated; samples or measurements shall be representative of the volume and nature of the monitored discharge. If no'discharge occurs during the entire monitoring period, it shall be stated on the Discharge Monitoring Report Form (EPA No. 3320-1) that no discharge or overflow occurred. Effluent samples must be obtained immediately after treated .wastewater flows over the 3-foot concrete weir. Influent samples must be taken at the influent channel before the bar screen. • 0 Part I Page 7 of 29 Permit No.: MT 0020311 C? E F, -I L J Monitoring Requirements Parameter Unit Sample Location Sample Frequency Sample Type' Flow m d Influent 1/Week Instantaneous mgd Effluent Continuous 5 mg/L Influent 3/Week Composite 5-Day Biological Oxygen mg/L Effluent 3/Week composite Demand (BOD5) % Removal4 NA 1/Month Calculated lbs/day Effluent I/Month Calculated mg/L Influent 3/Week Composite Total Suspended Solids mg/L Effluent 3/Week Composite (TSS) % Removal4 NA 1/Month Calculated lbs/day Effluent 1/Month Calculated pH S.U. Effluent Daily Instantaneous Temperature OF Effluent Daily Instantaneous E. coli Bacteria cfu/100ml Effluent 3/Week Grab Total Residual Chlorine2 mg/L Effluent Daily Grab Oil and Grease6 mg/L Effluent I/Month Grab Petroleum Hydrocarbons? mg/L Effluent I/Quarter Grab Total Ammonia, as N mg/L Effluent . 2/Month Composite Nitrate + Nitrite, as N mg/L Effluent 2/Month Composite Kjeldahl Nitrogen, Total, as N mg/L Effluent 2/Month Composite Total Nitro en as N3 mg/L NA 2/Month Calculated g , lbs/day NA 2/Month Calculated mg/L Effluent 2/Month Composite Total Phosphorus, as P lbs/day NA 2/Month Calculated Total Dissolved Solids (TDS) mg/L Effluent 1/Quarter Composite Dissolved Oxygen mg/L Effluent 1/Quarter Grab Whole Effluent Toxicity, Acute4 % Effluent Effluent 1/Quarter Composite Footnotes: 1. See Definition section at end of permit for explanation.of teens. 2. The Permittee is only required to sample for total residual chlorine if chlorine is used as a disinfectant in the treatment process. If chlorine is not used, write "NA" on the DMR for this parameter. 3. Calculated as the sum of Nitrate + Nitrite (as N) and Total Kjeldahl Nitrogen (as N) concentrations. 4. See narrative discussion in this section of permit for additional details. 5. Requires recording device or totalizer; permittee shall report daily maximum and daily average flow on DMR. 6. Use EPA Method 1664, Revision A: N-Hexane Extractable Material (HEM), or equivalent. 7. Use EPA Method 418. 1, Infrared Spectroscopy. Part I Page 8 of 29 Permit No.: MT 0020311 L' Monitoring Requirements (Continued) Parameter Unit Sample Frequency T Sample Type' ML. Antimony, Total Recoverable2 µg/L 2/Year 5 Composite 1 Arsenic, Total Recoverable2 µg/L 2/Years Composite 1 Beryllium, Total Recoverable2 µg/L 2/year Composite 1 Cadmium, Total Recoverable2 n/L 2/year 5 Composite 0.1 Chromium, Total Recoverable2 gg/L, 2/year 5 Composite 10 Copper, Total Recoverable2 µg/L 21year Composite 1 Lead, Total Recoverable2 gg/L 2/Years Composite 1 Mercury, Total Recoverable2 µg/L 2/year 5 Composite 0.1 Nickel, Total Recoverable2 gg/L 2/year Composite 10 Selenium, Total Recoverable2 gg/L 2/years Composite 1 Silver, Total Recoverable2 n/L 2/years Composite 1 Thallium, Total Recoverable2 µg/L 2/year 5 Composite 1 Zinc, Total Recoverable2 µg/L, 2/year Composite 10 Cyanide, Total gg/L 2/years Grab 5 Phenols, Total µg2, 2/year Grab 10 Hardness, Total (as CaCO3) mg/L 2/year 5 Grab 10 Volatile Organic Pollutants3 n/L 2/year 5 Composite 6 Semi-Volatile, Acid Compounds' gg/L 2/year 5 Composite 6 Semi-Volatile, Base Neutral' µg/L 2/year 5 Composite 6 Footnotes: 1. See Definition section at end of permit for explanation of terms. 2. Metals shall be analyzed as total recoverable, use EPA Method (Section) 4.1.4 [EPA 600/4-79-020, March 1983] or equivalent. 3. 40 CFR 122, Appendix J, Table 2, use EPA Method 1624 Revision B, or equivalent. 4. 40 CFR 122, Appendix J, Table 2, use EPA Method 1625 Revision B, or equivalent. 5. Sampling is required only in 2010 and 2011. This information will not be entered on the DMR form; a copy of the analytical laboratory report must be attached to the DMR for the applicable reporting period. 6. See approved method.for minimum level (ML). 7. Samples must be collected in the first and third calendar quarters of the calendar year. 0 Part I Page 9 of 29 Permit No.: MT 0020311 0 Reporting Re uirements Load Calculations In addition to reporting the concentration values, the monthly loads expressed in lbs/day must be calculated and reported for BOD5, TSS, total phosphorus and total nitrogen. The monthly loads must be calculated using the average daily flow rate: and daily average parameter concentration as shown in the following equations: Load (lb/day) Parameter concentration (mg/1) x Effluent Flow Rate (gpm) x (0.012) or Parameter concentration (mg/1) x Effluent Flow Rate (mgd) x (8.34) Percent (%) Removal The percent removal shall be calculated using the following formula: Influent Concentration - E went Concentration • % Removal = [Influent Concentration] X100% Where: Influent Concentration = Corresponding 30-Day average influent concentration based on the analytical results of the reporting period. Effluent Concentration = Corresponding 30-Day average effluent concentration based on the analytical results of the reporting period. Whole Effluent Toxici Testing - Acute Toxicity Starting in the third calendar quarter of 2009, the permittee shall conduct an acute static replacement toxicity test on a composite/grab sample of the effluent. Testing will employ two species per quarter and will consist of 5 effluent concentrations (100, 50, 25, 12.5, 6.25 percent effluent) and a control. Dilution water and the control shall consist of the receiving water. The replacement static toxicity tests shall be conducted in general accordance with the procedures set out in the latest revision of Methods for Measuring the Acute Toxicity of Effluent to Freshwater and Marine Organisms, EPA-600/4- 90/027 and the "Region VIII EPA NPDES Acute Test Conditions-State Renewal • Whole Effluent Toxicity". The permittee shall conduct acute 48-hour static renewal toxicity tests using the water flea (Ce>riodaphnia dubia) and 96-hour fathead minnow (Pimephales promelas). Part I Page 10 of 29 Permit No.: MT 0020311 • Acute toxicity occurs when 50 percent or more mortality is observed for either species at any effluent concentration. If more than 10 percent control mortality occurs, the test is considered invalid and shall be repeated until satisfactory control survival is achieved, unless a specific individual exception is granted by the Department. This exception may be granted if less than 10 percent mortality was observed at the dilutions containing high effluent concentrations. The quarterly results from the laboratory shall be reported along with the Discharge Monitoring Report (DMR) form submitted for the end of the reporting calendar quarter (e.g., whole effluent results for the reporting quarter ending March 31 shall be reported with the March DMR due April 28th with the remaining quarterly reports submitted with the June, September, and December DMR's). The format for the laboratory report shall be consistent with the latest revision of Region VIII Guidance for Acute Whole Effluent Reporting, and shall include all chemical and physical data as specified. D. Special Conditions Sewage Sludge: The use or disposal of sewage sludge must be in conformance with the Environmental Protection Agency (EPA) General Permit MTG650000 or an equivalent permit issued pursuant to 40 CFR 503. A notice of intent must be filed with the EPA and the Department in accordance with the timeframes and procedures identified in the applicable permit. All materials required by the General Permit to be submitted to the Department shall be signed in accordance with Part IV.G and sent to the address provided in Part II.D of this permit. The permittee shall not dispose of sewage sludge such that any portion thereof enters any state water, including ground water. The permittee shall notify the Department in writing 45 days prior to any change in sludge management at the facility. E. Pretreatment Requirements The Permittee shall not allow any user to introduce into a POTW any pollutants which cause Pass Through or Interference. These general prohibitions and the specific prohibitions in Part I.E.2 of this rule apply to all non-domestic sources introducing pollutants into a POTW whether or not the source is subject to other national pretreatment standards or any national, state or local pretreatment requirements. • 2. In addition, the following pollutants may not be introduced into a POTW: a. Pollutants which create a fire br explosion hazard in the POTW, including waste streams with a closed cup flashpoint of less than 140 Part I Page II of 29 Permit No.: MT 0020311 • degrees Fahrenheit or 60 degrees Celsius using the test methods specified in 40 CFR 261.21 b. Pollutants which will cause corrosive structural damage to the POTW, but in no case discharges with pH lower than 5.0, unless the works is specifically designed to accommodate such discharges; 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 (BOD, etc.), released in a discharge at a flow 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, but in no case heat in such quantities that the temperature at the POTW treatment plant exceeds 40 degrees Celsius (104 degrees Fahrenheit) unless the department, upon request of the POTW, approves alternative temperature limits; f. Petroleum oil, non-biodegradable cutting oil, or products of mineral oil origin in amounts that will cause Interference or Pass Through; g. Pollutants which result in the presence of toxic gases, vapors, or fumes within the POTW in a quantity that may cause acute worker health and safety problems; and h. Any trucked or hauled pollutants, except at discharge points designated by the POTW. 3. Publicly Owned Treatment Works. All POTWs must provide adequate notice to the Department of the following: a. Any new introduction of pollutants into the POTW from an indirect discharger which would be subject to federal effluent guidelines and standards [40CFR Subchapter N] if it were directly discharging those pollutants; and b. Any substantial change in the volume or character of pollutants being introduced into that POTW by a source introducing pollutants into the POTW at the time of issuance of the permit. c. For the purposes of this paragraph, adequate notice shall include information on: 1) The quality and quantity of effluent introduced into the POTW, and Part I • • Page 12 of 29 Permit No.: MT 0020311 2) Any anticipated impact of the change on the quantity or quality of effluent to be discharged'from the POTW. 0 Part II Page 13 of 29 Perrriit No.: MT 0020311 41 II. MONITORING, RECORDING AND REPORTING REQUIREMENTS A. Re resentative Sam lin Samples taken in compliance with the monitoring requirements established under Part I shall be collected from the effluent stream prior to discharge into the receiving waters. Samples and measurements shall be representative of the volume and nature of the monitored discharge. Sludge samples shall be collected at a location representative of the quality of sludge immediately prior to use- disposal practice. B. Monitorin Procedures Monitoring must be conducted according to test procedures approved under Part 136, Title 40 of the Code of Federal Regulations, unless other test procedures have been specified in this permit. See Part I.C. for any applicable sludge monitoring procedures. All flow-measuring and flow-recording devices used in obtaining data submitted in self-monitoring reports must indicate values within 10 percent of the actual flow being measured. C. Penalties for Tampering The Montana Water Quality Act provides that any person who falsifies, tampers with, or knowingly renders inaccurate, any monitoring device or method required to be maintained under this permit shall, upon conviction, be punished by a fine of not more than $25,000, or by imprisonment for not more than six months, or by both. D. Reporting of Monitorin Results Effluent monitoring results obtained during the previous month(s) shall be summarized for each month and reported on a Discharge Monitoring Report Form (EPA No. 3320-1), postmarked no later than the 28th day of the month following the completed reporting period. Whole effluent toxicity (biomonitoring) results must be reported with copies of the laboratory analysis report on forms from the most recent version of EPA Region VIII's "Guidance for Whole Effluent Reporting". If no discharge occurs during the reporting period, "no discharge" shall be reported on the report form. Legible copies of these, and all other reports required herein, shall be signed and certified in accordance with the "Signatory Requirements" (see Part IV.G of this permit), and submitted to the Department at the following addresses: E Part Il Page 14 of 29 Permit No.: MT 0020311 • Montana Department of Environmental Quality Water Protection Bureau PO Box 200901 Helena, Montana 59620- 0901 Phone: (406) 444-3080 E. Compliance Schedules Reports of compliance or noncompliance with, or any progress reports on interim and final requirements contained in any Compliance Schedule of this permit shall be submitted no later than 14 days following each schedule date. F. Additional Monitorin b the Permittee If the permittee monitors any pollutant more frequently than required by this permit, using approved analytical methods as specified in this permit, the results of this monitoring shall be included in the calculation and reporting of the data submitted in the Discharge Monitoring Report. Such increased frequency shall also be indicated. G. Records Contents Records of monitoring information shall include: • 1. The date, exact place, and time of sampling or measurements; 2. The initials or name(s) of the individual(s) who performed the sampling or measurements; The date(s) analyses were performed; 4. The time analyses were initiated; 5. The initials or name(s) of individual(s) who performed the analyses; 6. References and written procedures, when available, for the analytical techniques or methods used; and 7. The results of such analyses, including the bench sheets, instrument readouts, computer disks or tapes, etc., used to determine these results. H. Retention of Records The permittee shall retain records of all monitoring information, including all calibration and maintenance records and all original strip chart recordings for continuous monitoring instrumentation, copies of all reports required. by this permit, and records of all data used to complete the application for this permit, for a period of at least three years from the date of the sample, measurement, report or application. This period may be extended by request of the Department at any time. Data collected on site, copies of Discharge Monitoring Reports, and a copy Part II Page 15 of 29 Permit No.: MT 0020311 • of this MPDES permit must be maintained on site during the duration of activity at the permitted location. Twen -four Hour Notice of Noncompliance Reporting The permittee shall report any serious incident of noncompliance affecting the environment as soon as possible, but no later than twenty-four (24) hours from the'time the permittee first became aware of the circumstances. The report shall be made to the Water Protection Bureau at (406) 444-3080 or the Office of Disaster and Emergency Services at (406) 841-3911. The following examples are considered serious incidents: a. Any noncompliance which may seriously endanger health or the environment; b. Any unanticipated bypass which exceeds any effluent limitation in the permit (See Part III.G of this permit, "Bypass of Treatment Facilities"); or Any upset which exceeds any effluent limitation in the permit (See Part III.H of this permit, "Upset Conditions"). 2. A written submission shall also be provided within five days of the time that the permittee becomes aware of the circumstances. The written submission shall contain: a. A description of the noncompliance and its cause; b. The period of noncompliance, including exact dates and times; The estimated time noncompliance is expected to continue if it has not been corrected; and d. Steps taken or planned to reduce, eliminate, and prevent reoccurrence of the noncompliance. 3. The Department may waive the written report on a case-by-case basis if the oral report has been received within 24 hours by the Water Protection Bureau, by phone, (406) 444-3080. 4. Reports shall be submitted to the addresses in Part II.D of this permit, "Reporting of Monitoring Results". J. Other Noncompliance Reporting Instances of noncompliance not required to be reported within 24 hours shall be reported at the time that monitoring reports for Part II.D of this permit are `submitted. The reports shall contain the information listed. in Part 1112 of this permit. LJ Part 11 Page 16 of 29 Permit No.: MT 0020311 K. Inspection and Ent The permittee shall allow the head of the Department or the Regional Administrator, or an authorized representative upon the presentation of credentials and other documents as may be required by law, to: 1. Enter upon the permittee's premises where a regulated facility or activity is located or conducted, or where records must be kept under the conditions of this permit; 2. Have access to and copy, at reasonable times, any records that must be kept under the conditions of this permit; Inspect at reasonable times any facilities, equipment (including monitoring and control equipment), practices, or operations regulated or required under this permit; and 4. Sample or monitor at reasonable times, for the purpose of assuring permit compliance, any substances or parameters at any location. 0 E Part III Page 17 of 29 Permit No.: MT 0020311 III. COMPLIANCE RESPONSIBILITIES A. Duty to Comply The permittee must comply with all conditions of this permit. Any permit noncompliance constitutes a violation of the Act and is grounds for enforcement action; for permit termination, revocation and reissuan ce, or modification; or for denial of a permit renewal application. The permittee shall give the Department advance notice of any planned changes at the permitted facility or of an activity which may result in permit noncompliance. B. Penalties for Violations of Permit Conditions The Montana Water Quality Act provides that any person who violates a permit condition of the Act is subject to civil or criminal penalties not to exceed $25,000 per day or one year in prison, or both, for the first conviction, and $50,000 per day of violation or by imprisonment for not more than two years, or both, for subsequent convictions. MCA 75-5-611(a) also provides for administrative penalties not to exceed $10,000 for each day of violation and up to a maximum not to exceed $100,000 for any related series of violations. Except as provided in permit conditions on Part III.G of this permit, "Bypass of Treatment Facilities" and Part III.H of this permit, "Upset Conditions", nothing in this permit shall be construed to relieve the permittee of the civil or criminal penalties for noncompliance. C. Need to Halt or Reduce Activity not a Defense It shall not be a defense for a permittee in an enforcement action that it would have been necessary to halt or reduce the permitted activity in order to maintain compliance with the conditions of this permit. D. Dut to Mitigate The permittee shall take all reasonable steps to minimize or prevent any discharge in violation of this permit which has a reasonable likelihood of adversely affecting human health or the environment. E. Proper Operation and Maintenance The permittee shall at all times properly operate and maintain all facilities and systems of treatment and control (and related appurtenances) which are installed or used by the permittee to achieve compliance with the conditions of this permit. Proper operation and maintenance also includes adequate laboratory controls and appropriate quality assurance procedures. This provision requires the. operation of back-up or auxiliary facilities or similar systems which are installed by a permittee only when the operation is necessary to achieve compliance with the conditions of the permit. However,'the permittee shall operate, as a minimum, one complete set of each main line unit treatment process whether or not this process is needed to achieve permit effluent compliance. • Part III Page 18 of 29 • Permit No.: MT 0020311 F. Removed Substances Collected screenings, grit, solids, sludges, or other pollutants removed in the course of treatment shall be disposed of in such a manner so as to prevent any pollutant from entering any waters of the state or creating a health hazard. Sludge shall not be directly blended with or enter either the final plant discharge and/or waters of the United States. 2. Any sludges removed from the facility shall be disposed of in accordance with 40 CFR 503, 258 or other applicable rule. EPA and MDEQ shall be notified at least 180 days prior to such disposal taking place. 3. The permittee shall provide certification that all applicable provisions of 40 CFR Parts 503 and 258 have been met for the land application or landfill disposal of sewage sludge. Certification shall be submitted annually with the sludge reporting form and must contain the following statement: "I certify under penalty of law, that all of the applicable provisions of 40 CFR Part (503/258) have been met when municipal sewage sludge is- (beneficially used/disposed of at a landfill). This determination has been made under my direction and supervision in accordance with the system designed to ensure that qualified personnel properly gather and evaluate the information used to determine that 40 CFR.Part (503/258) have been met. I am aware that there are significant penalties for false certification including the possibility of fine and imprisonment." G. Bypass of Treatment Facilities 1. Bypass not exceeding limitations. The permittee may allow any bypass to occur which does not cause effluent limitations to be exceeded, but only if it also is for essential maintenance to assure efficient operation. These bypasses are not subject to the provisions of Parts III.G.2 and III.G.3 of this permit. 2. Notice: a. Anticipated bypass. If the permittee knows in advance of the need for a bypass, it shall submit prior notice, if possible at least ten (10) days before the date of the bypass. b. Unanticipated bypass. The permittee shall submit notice of an unanticipated bypass as required under Part 11.1 of this permit, "Twenty- four Hour Reporting". 3. Prohibition of bypass: ` Part III Page 19 of 29 Permit No.: MT 0020311 C7 a. Bypass is prohibited and the Department may take enforcement action against a permittee for a bypass, unless: 1) The bypass was unavoidable to prevent loss of life, personal injury, or severe property damage; 2) There were no feasible alternatives to the bypass, such as the use of auxiliary treatment facilities, retention of untreated wastes, or maintenance during normal periods of equipment downtime. This condition is not satisfied if adequate back-up equipment should have been installed in the exercise of reasonable engineering judgment to prevent a bypass which occurred during normal periods of equipment downtime or preventive maintenance; and 3) The permittee submitted notices as required under Part III.G.2 of this permit. b. The Department may approve an anticipated bypass, after considering its adverse effects, if the Department determines that it will meet the three conditions listed above in Part III.G.3.a of this permit. 0 H. Upset Conditions Effect of an upset. An upset constitutes an affirmative defense to an action brought for noncompliance with technology based permit effluent limitations if the requirements of Part III.H.2 of this permit are met. No determination made during administrative review of claims that noncompliance was caused by upset, and before an action for noncompliance, is final administrative action subject to judicial review (i.e. Permittees will have the opportunity for a judicial determination on any claim of upset only in an enforcement action brought for noncompliance with technology-based permit effluent limitations). 2. Conditions necessary for a demonstration of upset. A permittee who wishes to establish the affirmative defense of upset shall demonstrate, through properly signed, contemporaneous operating logs, or other relevant evidence that: a. An upset occurred and that the permittee can identify the cause(s) of the upset; b. The permitted facility was at the time being properly operated; 0 40 • • 0 Part III Page 20 of 29 Permit No.: MT 0020311 The permittee submitted notice of the upset as required under Part ILI of this permit, "Twenty-four Hour Notice of Noncompliance Reporting"; and d. The permittee complied with any remedial measures required under Part IILD of this permit, "Duty to Mitigate". Burden of proof. In any enforcement proceeding, the permittee seeking to establish the occurrence of an upset has the burden of proof. C 0 IV. GENERAL REQUIREMENTS Part IV Page 21 of 29 Permit No.: MT 0020311 A. Planned Changes The permittee shall give notice to the Department as soon as possible of any planned physical alterations or additions to the permitted facility. Notice is required only when: 1. The alteration or addition could significantly change the nature or increase the quantity of pollutant discharged. This notification applies to pollutants which are not subject to effluent limitations in the permit; or 2. There are any planned substantial changes to the existing sewage sludge management practices of -storage and disposal. The permittee shall give the Department notice of any planned changes at least 180 days prior to their implementation. B. Anticipated Noncompliance The permittee shall give advance notice to the Department of any planned changes in the permitted facility or activity which may result in noncompliance with permit requirements. • C. Permit Actions This permit may be revoked, modified and reissued, or terminated for cause. The filing of a request by the permittee for a permit modification, revocation and reissuance, or termination, or a notification of planned changes or anticipated noncompliance, does not stay any permit condition. D. Dut to Rea 1 If the permittee wishes to continue an activity regulated by this permit after the expiration date of this permit, the permittee must apply for and obtain a new permit. The application must be submitted at least 180 days before the expiration date of this permit. E. Duty to Provide Information. The permittee shall furnish to the Department, within a reasonable time, any information which the Department may request to determine whether cause exists for revoking, modifying and reissuing, or terminating this permit, or to determine compliance with this permit. The permittee shall also furnish to the Department, upon request, copies of records required to be kept by this permit. F. Other Information When the permittee becomes aware that it failed to submit any relevant facts in a permit application, or submitted incorrect information in a permit application or • .any report to the Department, it shall promptly submit such facts or information with a narrative explanation of the circumstances of the omission or incorrect submittal and why they weren't supplied earlier. Part N Page 22 of 29 Permit No.: MT 0020311 • G. Signatory Requirements All applications, reports or information submitted to the Department shall be signed and certified. I . All permit applications shall be signed by either a principal executive officer or ranking elected official. 2. All reports required by the permit and other information requested by the Department shall be signed by a person described above or by a duly authorized representative'of that person. A person is considered a duly authorized representative only if: a. The authorization is made in writing by a person described above and submitted to the. Department; and b. The authorization specifies either an individual or a position having responsibility for the overall operation of the regulated facility, such as the position of plant manager, superintendent, position of equivalent responsibility, or an individual or position having overall responsibility for environmental matters. (A duly authorized representative may thus be either a named individual or an individual occupying a named position.) Changes to authorization. If an authorization under Part IV.G.2 of this permit is no longer accurate because a different individual or position has responsibility for the overall operation of the facility, a new authorization satisfying the requirements of Part IV_G.2 of this permit must be submitted to the Department prior to or together with any reports, information, or applications to be signed by an authorized representative. 4. Certification. Any person signing a document under this section shall make the following certification: "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 fine . and imprisonment for knowing violations." Part 1V Page 23 of 29 Permit No.: MT 0020311 H. Penalties for Falsification of Reports The Montana Water Quality Act provides that any person who knowingly makes any false statement, representation, or certification in any record or other document submitted or required to be maintained under this permit, including monitoring reports or reports of compliance or noncompliance shall, upon conviction be punished by a fine of not more that $25,000 per violation, or by imprisonment for not more than six months per violation, or by both. Availability of Reports Except for data determined to be confidential under 40 CFR Part 2, all reports prepared in accordance with the terms of this permit shall be available for public inspection at the offices of the Department. As required by the Clean Water Act, permit applications, permits and effluent data shall not be considered confidential. Oil and Hazardous Substance Liability Nothing in this permit shall be construed to preclude the institution of any legal action or relieve the permittee from any responsibilities, liabilities, or penalties to which the permittee is or may be subject under Section 311 of the Clean Water Act. K. Propertyor Water Rights The issuance of this permit does not convey any property or water rights of any sort, or any exclusive privileges, nor does it authorize any injury to private property or any invasion of personal rights, nor any infringement of federal, state or local laws or regulations. L. Severability The provisions of this permit are severable, and if any provision of this permit, or the application of any provision of this permit to any circumstance, is held invalid, the application of such provision to other circumstances, and the remainder of this permit, shall not be affected thereby. M. Transfers This permit may be automatically transferred to a new permittee if: The current permittee notifies the Department at least 30 days in advance of the proposed transfer date; 2. The notice includes a written agreement between the existing and new permittees containing a specific date for transfer of permit responsibility, coverage, and liability between them; 3. The Department does not notify the existing permittee and the proposed new • permittee of an intent to revoke or modify and reissue the permit. If this notice is not received, the transfer is effective on the date specified in the agreement mentioned in Part IV.M.2 of this permit; and Part IV Page 24 of 29 Permit No.: MT 0020311 0 4. Required annual and application fees have been paid. N. Fees The permittee is 'required to submit payment of an annual fee as set forth in ARM 17.30.201. If the permittee fails to pay the annual fee within 90 days after the due date for the payment, the Department may: Impose an additional assessment consisting of 15% of the fee plus interest on the required fee computed at the rate established under 15-31-510(3), MCA, or 2. . Suspend the processing of the application for a permit or authorization or, if the nonpayment involves an annual permit fee, suspend the permit, certificate or authorization for which the fee is required. The Department may lift suspension at any time up to one year after the suspension occurs if the holder has paid all outstanding fees, including all penalties, assessments and interest imposed under this sub-section. Suspensions are limited to-one year, after which the permit will be terminated. 0. Reopener Provisions This permit may be reopened and modified (following proper administrative • procedures) to include the appropriate effluent limitations (and compliance schedule, if necessary), or other appropriate requirements if one or more of the following events occurs: Water Quality Standards: The water quality standards of the receiving water(s) to which the permittee discharges are modified in such a manner as to require different effluent limits than contained in this permit. 2. Water Quality Standards are Exceeded: If it is found that water quality standards or trigger values in the receiving stream are exceeded either for parameters included in the permit or others, the department may modify the effluent limits or water management plan. TMDL or Wasteload Allocation: TMDL requirements or a wasteload allocation is developed and approved by the Department and/or EPA for incorporation in this permit. 4. Water Quality Management Plan: A revision to the current water quality management plan is approved and adopted which calls for different effluent limitations than contained in this permit. 5. Sewage Sludge: There have been. substantial changes (or such changes are • planned) in sludge use.or disposal practices; applicable management practices or numerical limitations for pollutants in sludge have been promulgated which are more stringent than the requirements in this permit; Part IV Page 25 of 29 Pernnit No.: MT 002031 l and/or it has been determined that the permittee's sludge use or disposal practices do not comply with existing applicable state or federal regulations. E 40 Part V Page 26 of 29 Permit No.: MT 0020311 40 V. DEFINITIONS 1. "Act" means the Montana Water Quality Act, Title 75, chapter 5, MCA. 2. "Administrator" means the administrator of the United States Environmental Protection Agency. 3. "Acute Toxicity" occurs when 50 percent or more mortality is observed for either species (See Part I.C of this permit) at any effluent concentration. Mortality in the control must simultaneously be 10-percent or less for the effluent results to be considered valid. 4. "Annual Average Load" means the arithmetic mean of all 30-day or monthly average loads reported during the calendar year for a monitored parameter. "Arithmetic Mean" or "Arithmetic Average" for any set of related values means the summation of the individual values divided by the number of individual values. 6. "Average monthly limitation" means the highest allowable average of daily discharges over a calendar month, calculated as the sum of all daily discharges measured during a calendar month divided by the number of daily discharges measured during that month. 7. "Average weekly limitation" means the highest allowable average of daily discharges over a calendar week, calculated as the sum of all daily discharges measured during a calendar week divided by the number of daily discharges measured during that week. "BOD5" means the five-day measure of pollutant parameter biochemical oxygen demand. 9. "Bypass" means the intentional diversion of waste streams from any portion of a treatment facility. 10. "CBOD5" means the five-day measure of pollutant parameter carbonaceous biochemical oxygen demand. 11. "Composite samples" shall be flow proportioned. The composite sample shall, as a minimum, contain at least four (4) samples collected over the compositing period. Unless otherwise specified, the time between the collection of the first sample and the last sample shall not be less than six (6) hours nor more than 24 hours. Acceptable methods for preparation of composite samples are as follows: a. Constant time interval between samples, sample volume proportional to flow rate at time of sampling; ` Part V Page 27 of 29 Permit No.: MT 0020311 b. Constant time interval between samples, sample volume proportional to total flow (volume) since last sample. For the first sample, the flow rate at the time the sample was collected may be used; C. Constant sample volume, time interval between samples proportional to flow (i.e. sample taken every "X" gallons of flow); and, d. Continuous collection of sample, with sample collection rate proportional to flow rate. 12. "Daily Discharge" means the discharge of a pollutant measured during a calendar day or any 24-hour period that reasonably represents the calendar day for purposes of sampling. For pollutants with limitations expressed in units of mass, the daily discharge is calculated as the total mass of the pollutant discharged over the day. For pollutants with limitations expressed in other units of measurement, the daily discharge is calculated as the average measurement of the pollutant over the day. 13. "Daily Maximum Limit" means the. maximum allowable discharge of a pollutant during a calendar day. Expressed as units of mass, the daily discharge is cumulative mass discharged over the course of the day. Expressed as a concentration, it is the arithmetic average of all measurements taken that day. • 14. "Department" means the Montana Department of Environmental Quality (MDEQ) established by 2-15-3501, MCA. 15. "Director" means the Director of the Montana Department of Environmental Quality. 16. "Discharge" means the injection, deposit, dumping, spilling, leaking, placing, or failing to remove any pollutant so that it or any constituent thereof may enter into state waters, including ground water. 17. "EPA" means the United States Environmental Protection Agency. 1$. "Federal Clean Water Act" means the federal legislation at 33 USC 1251, et seq. 19. "Geometric Mean" means the value obtained by taking the Nth root of the product of the measured values. 20. "Grab Sample" means a sample which is taken from a waste stream on a one- time basis without consideration of flow rate of the effluent or without consideration for time.. 21. "Indirect discharge" means the introduction of pollutants into a POTW from any non-domestic source regulated under Section 307(b), (c) or (d) of the Federal Clean Water'Act. Part V Page 28 of 29 Permit No.: MT 0020311 0 22. "Industrial User" means a source of Indirect Discharge. 23. "Instantaneous Maximum. Limit" means the maximum allowable concentration of a pollutant determined from the analysis of any discrete or composite sample collected, independent of the flow rate and the duration of the sampling event. 24. "Instantaneous Measurement", for monitoring requirements, means a single reading, observation, or measurement. 25. "Interference" means a discharge which, alone or in conjunction with other contributing discharges a. Inhibits or disrupts the POTW, its treatment processes or operations, or its sludge processes, use or disposal; and b. Therefore causes a violation of any requirement of the POTW's MPDES permit (including an increase in the magnitude or duration of a violation) or causes the prevention of sewage sludge use or disposal in compliance with the following statutes and regulations: Section 405 of the Clean Water Act; 40 CFR Part 503 - Standards for the Use and Disposal of Sewage Sludge; Resource Conservation and Recovery Act (RCRA); 40 CFR Part 258 - Criteria for Municipal Solid Waste Landfills; and/or any State regulations regarding the disposal of sewage sludge. 26. "Maximum daily discharge limitation" means the highest allowable daily discharge. 27. "Minimum Level" (ML) of quantitation means the lowest level at which the entire analytical system gives a recognizable signal and acceptable calibration point far the analyte, as determined by the procedure set forth at 40 CFR 136. In most cases the ML is equivalent to the Required Reporting Value (RRV) unless other wise specified in the permit. (ARM 17.30.702(22)) 28. "Mixing zone" means a limited area of a surface water body or aquifer where initial dilution of a discharge takes place and where certain water quality standards may be exceeded. 29. "Nondegradation" means the prevention of a significant change in water quality that lowers the quality of high-quality water for one or more parameters. Also, the prohibition of any increase in discharge that exceeds the limits established under or determined from a permit or approval issued by the Department prior to April 29, 1993. 30. "Pass through" means a discharge which exits the POTW into waters of the State of Montana in quantities or concentrations which, alone or in conjunction with other discharges, is a cause of a violation of any requirement of the POTW's MPDES permit (including an increase in the magnitude or duration of a violation). ?J Part V Page 29 of 29 Permit No.: MT 0020311 31. "POTW" means a publicly owned treatment works. 32. "Regional Administrator" means the administrator of Region VIII of EPA, which has jurisdiction over federal water pollution control activities in the state of Montana. 33. "Severe property damage" means substantial physical damage to property, damage to the treatment facilities which causes them to become inoperable, or substantial and permanent loss of natural resources which can reasonably be expected to occur in the absence of a bypass. Severe property damage does not mean economic loss caused by delays in production. 34. "Sewage Sludge" means any solid, semi-solid or liquid residue generated during the treatment of domestic sewage and/or a combination of domestic sewage and industrial waste of a liquid nature in a treatment works. Sewage sludge includes, but is not limited to, domestic septage; scum or solids removed in primary, secondary, or advanced wastewater treatment processes; and a material derived from sewage sludge. Sewage sludge does not include ash generated during the incineration of sewage sludge or grit and screenings generated during preliminary treatment of domestic sewage in a treatment works. 35. "TIE" means a toxicity identification evaluation. 36. "TMDL" means the total maximum daily load limitation of a parameter, representing the estimated assimilative capacity for a water body before other designated uses are adversely affected. Mathematically, it is the sum of wasteload allocations for point sources, load allocations for non-point and natural background sources, and a margin of safety. 37. "TRE" means a toxicity reduction evaluation. 38. "TSS" means the pollutant parameter total suspended solids. 39. "Upset" means an exceptional incident in which there is unintentional and temporary noncompliance with technology-based permit effluent limitations because of factors beyond the reasonable control of the permittee. An upset does not include noncompliance to the extent caused by operational error, improperly designed treatment facilities, inadequate treatment facilities, lack of preventive maintenance, or careless or improper operation.