COLORADO DEPARTMENT OF PUBLIC HEALTH AND ENVIRONMENTWater Quality Control DivisionAUTHORIZATION TO DISCHARGE UNDER THECOLORADO DISCHARGE PERMIT SYSTEMPERMIT NUMBER CO0020281In compliance with the provisions of the Colorado Water Quality Control Act, (25-8-101 et seq., CRS, 1973 as amended), for both discharges to surface and ground waters, and the Federal Water Pollution Control Act, as amended (33 U.S.C. 1251 et seq.; the "Act"), for discharges to surface waters only, theTown of Del Norteis authorized to discharge from the Town of Del Norte wastewater treatment plant located SE1/4 of Section 29 and the SW 1/4 of Section 28; T40N, R6E. 140 Spruce St, Del Norte, CO 81132; at 37.67679° N, 106.32978° Wto the Rio Grande Riverin accordance with effluent limitations, monitoring requirements and other conditions set forth in Parts I and II hereof. All discharges authorized herein shall be consistent with the terms and conditions of this permit.The applicant may demand an adjudicatory hearing within thirty (30) calendar days of the date of issuance of the final permit determination, per the Colorado State Discharge Permit System Regulation 61.7(1). Should the applicant choose to contest any of the effluent limitations, monitoring requirements or other conditions contained herein, the applicant must comply with Section 24-4-104 CRS 1973 and the Colorado State Discharge Permit System Regulations. Failure to contest any such effluent limitation, monitoring requirement, or other condition, constitutes consent to the condition by the applicant.This permit and the authorization to discharge shall expire at midnight, December 31, 2024Issued and Signed XXXCOLORADO DEPARTMENT OF PUBLIC HEALTH AND ENVIRONMENTPUBLIC NOTICE VERSION OF PERMIT7/13/2023Andrew Sayers-Fay, Permits Section ManagerWater Quality Control DivisionModification 1 – Minor Amendment: Issued XX/XX/XXXX and Effective XX/XX/XXXX (Part I.B.5.a)Originally Signed and Issued November 27, 2019; Effective January 1, 2020PART IPage 2 of 36Permit No.: CO0020281LIST OF CONTENTSPART I......................................................................................................................................................................................3A. EFFLUENT LIMITATIONS AND MONITORING REQUIREMENTS ..........................................................................................31. Permitted Feature(s).......................................................................................................................................................32. Limitations, Monitoring Frequencies and Sample Types for Effluent Parameters ...........................................33. Monitoring Frequency and Sample Type Influent Parameters..............................................................................64. Special Studies and Additional Monitoring.................................................................................................................6B. TERMS AND CONDITIONS ........................................................................................................................................................71. Service Area ......................................................................................................................................................................72. Design Capacity.................................................................................................................................................................73. Expansion Requirements................................................................................................................................................74. Facilities Operation and Maintenance.........................................................................................................................85. Acute WET Testing -Outfall(s): 001A...........................................................................................................................86. Compliance Schedule(s)................................................................................................................................................107. Pretreatment Program - Industrial Waste Management........................................................................................12C. DEFINITION OF TERMS ..........................................................................................................................................................14D. pERMIT sPECIFIC Monitoring, SAmpling and reporting requirements .......................................................................201. Routine Reporting of Data ..........................................................................................................................................202. Annual Biosolids Report................................................................................................................................................203. Representative Sampling..............................................................................................................................................214. Influent and Effluent Sampling Points.......................................................................................................................215. Analytical and Sampling Methods for Monitoring and Reporting ........................................................................216. Flow Measuring Devices................................................................................................................................................22PART II..................................................................................................................................................................................24A. DUTY TO COMPLY....................................................................................................................................................................24B. DUTY TO REAPPLY...................................................................................................................................................................24C. NEED TO HALT OR REDUCE ACTIVITY NOT A DEFENSE......................................................................................................25D. DUTY TO MITIGATE .................................................................................................................................................................25E. PROPER OPERATION AND MAINTENANCE.............................................................................................................................25F. PERMIT ACTIONS......................................................................................................................................................................25G. PROPERTY RIGHTS ..................................................................................................................................................................25H. DUTY TO PROVIDE INFORMATION .........................................................................................................................................25I. INSPECTION AND ENTRY.........................................................................................................................................................25J. MONITORING AND RECORDS ..................................................................................................................................................26K. SIGNATORY REQUIREMENTS...................................................................................................................................................26L. REPORTING REQUIREMENTS...................................................................................................................................................27M. BYPASS......................................................................................................................................................................................29N. UPSET........................................................................................................................................................................................29O. REOPENER CLAUSE..................................................................................................................................................................30P. OTHER INFORMATION .............................................................................................................................................................30Q. SEVERABILITY...........................................................................................................................................................................31R. NOTIFICATION REQUIREMENTS..............................................................................................................................................31S. RESPONSIBILITIES ....................................................................................................................................................................31T. OIL AND HAZARDOUS SUBSTANCES LIABILITY.....................................................................................................................31U. EMERGENCY POWERS..............................................................................................................................................................31V. CONFIDENTIALITY....................................................................................................................................................................31W. FEES...........................................................................................................................................................................................32X. DURATION OF PERMIT.............................................................................................................................................................32Y. SECTION 307 TOXICS...............................................................................................................................................................32PART III..................................................................................................................................................................................33PART IPage 3 of 36Permit No.: CO0020281PART IA. EFFLUENT LIMITATIONS AND MONITORING REQUIREMENTS1. Permitted Feature(s)Beginning no later than the effective date of this permit and lasting through the expiration date, the permittee is authorized to discharge from, and self monitoring samples taken in accordance with the monitoring requirements shall be obtained from permitted feature(s):001A following disinfection and prior to mixing with the receiving stream. 37.67679° N, 106.32978° WThe location(s) provided above will serve as the point(s) of compliance for this permit and are appropriate as they are located after all treatment and prior to discharge to the receiving water. Any discharge to the waters of the State from a point source other than specifically authorized by this permit is prohibited.In accordance with the Water Quality Control Commission Regulations for Effluent Limitations, Section 62.4, and the Colorado Discharge Permit System Regulations, Section 61.8(2), 5 C.C.R. 1002-61, the permitted discharge shall not contain effluent parameter concentrations which exceed the limitations specified below or exceed the specified flow limitation.2. Limitations, Monitoring Frequencies and Sample Types for Effluent ParametersIn order to obtain an indication of the probable compliance or noncompliance with the effluent limitations specified in Part I.A, the permittee shall monitor all effluent parameters at the frequencies and sample types specified below. Such monitoring will begin immediately and last for the life of the permit unless otherwise noted. The results of such monitoring shall be reported on the Discharge Monitoring Report form (See Part I.D.)Self-monitoring sampling by the permittee for compliance with the effluent monitoring requirements specified in this permit, shall be performed at the location(s) noted in Part I.A.1 above. If the permittee, using an approved analytical method, monitors any parameter more frequently than required by this permit, then the results of such monitoring shall be included in the calculation and reporting of the values required in the Discharge Monitoring Report Form (DMRs) or other forms as required by the Division. Such increased frequency shall also be indicated.Percentage Removal Requirements (BOD5 and TSS Limitations) - If noted in the limits table(s), the arithmetic mean of the BOD5 and TSS concentrations for effluent samples collected during the DMR reporting period shall demonstrate a minimum of eighty-five percent (85%) removal of both BOD5 and TSS, as measured by dividing the respective difference between the mean influent and effluent concentrations for the DMR monitoring period by the respective mean influent concentration for the DMR monitoring period, and multiplying the quotient by 100.In the previous permit, the facility showed that inflow and infiltration (I/I) problems contributed to the inability to meet the BOD5 percent removal requirements. Because the facility does not exceed the 120 gallons per capita per day threshold used by the division to screen for excessive infiltration, the facility no longer meets the requirements in 40 CFR Part 35.2005(b)(16) and 40 CFR Part 33.103(d). Therefore, an 85% BOD5 removal requirement is included in the permit.The TSS percent removal requirement will continue to be waived as allowed by Regulation No. 62, Section 62.5 (3).Oil and Grease Monitoring: For every outfall with oil and grease monitoring, in the event an oil sheen or floating oil is observed, a grab sample shall be collected and analyzed for oil and grease, and reported on the appropriate DMR under parameter 03582. In addition, corrective action shall be taken immediately to mitigate the discharge of oil and grease. A description of the corrective action taken should be included with the DMR.PART IPage 4 of 36Permit No.: CO0020281 Total Residual Chlorine: Monitoring for TRC is required only when chlorine is in use.Flow Recording Device: For this facility, a single flow recording device is provided and is located at the point of discharge from the treatment plant. Since effluent flows will not be significantly different from influent flows, the single flow measurement device will be used for the recording and reporting of both influent and effluent flows. Reported effluent flows will be used to monitor compliance with the effluent flow limitation.PERMITTED FEATURE/LIMIT SET 001A

PART IPage 5 of 36Permit No.: CO0020281

PART IPage 6 of 36Permit No.: CO0020281

3. Monitoring Frequency and Sample Type Influent ParametersRegardless of whether or not an effluent discharge occurs and in order to obtain an indication of the current influent loading as compared to the approved capacity specified in Part I.A.3 and Part I.B.2; the permittee shall monitor influent parameters at the following required frequencies, the results to be reported on the Discharge Monitoring Report (See Part I.D):If the permittee monitors any parameter more frequently than required by the permit, using an approved test procedure or as specified in the permit, the result of this monitoring shall be included in the calculation and reporting of data to the Division.Self-monitoring samples taken in compliance with the monitoring requirements specified below shall be taken at the following location(s): Outfall 300I, at a representative point prior to biological treatment.PERMITTED FEATURE 300I

1 The % capacity is to be reported against the listed capacities of 0.99 MGD for the hydraulic capacity and 450 BOD5 for the organic capacities as noted in Site Approval 3602. The percentage should be calculated using the 30-day average values divided by the corresponding capacity, times 100.4. Special Studies and Additional Monitoringa. Inflow/Infiltration Study –The Del Norte Sanitary Sewer System Rehabilitation Project shall identify andrepair any sources of inflow and infiltration located in Del Norte’s collection system.

PART IPage 7 of 36Permit No.: CO0020281All special studies must be submitted to the Division accompanied by a fully completed “Permit Narrative Conditions Form” available at https://www.colorado.gov/pacific/cdphe/wq-permit-forms.B. TERMS AND CONDITIONS1. Service AreaAll wastewater flows contributed in the service area may be accepted by the Town of Del Norte for treatment at the permittee's wastewater treatment plant provided that such acceptance does not cause or contribute to an exceedance of the throughput or design capacity of the treatment works or the effluent limitations in Part I.A, or constitute a substantial impact to the functioning of the treatment works, degrade the quality of the receiving waters, or harm human health, or the environment.In addition, the permittee shall enter into and maintain service agreements with any municipalities that discharge into the wastewater treatment facility. The service agreements shall contain all provisions necessary to protect the financial, physical, and operational integrity of the wastewater treatment works.2. Design CapacityBased on Site Approval 3602, the design capacity of this domestic wastewater treatment works is 0.99 million gallons per day (MGD) for hydraulic flow (30-day average) and 450 lbs. BOD5 per day for organic loading (30-day average).3. Expansion RequirementsPursuant to Colorado Law, C.R.S. 25-8-501 (5 d & e), the permittee is required to initiate engineering and financial planning for expansion of the domestic wastewater treatment works whenever throughput reaches eighty (80) percent of the treatment capacity. Such planning may be deemed unnecessary upon a showing that the area served by the domestic wastewater treatment works has a stable or declining population; but this provision shall not be construed as preventing periodic review by the Division should it be felt that growth is occurring or will occur in the area.The permittee shall commence construction of such domestic wastewater treatment works expansion whenever throughput reaches ninety-five (95) percent of the treatment capacity or, in the case of a municipality, either commence construction or cease issuance of building permits within such municipality until such construction is commenced; except that building permits may continue to be issued for any construction which would not have the effect of increasing the input of wastewater to the sewage treatment works of the municipality involved.Where unusual circumstances result in throughput exceeding 80% of treatment capacity, the permittee may, in lieu of initiating planning for expansion, submit a report to the Division that demonstrates that it is unlikely that the event will reoccur, or even if it were to reoccur, that 95% of the treatment capacity would not be exceeded.Where unusual circumstances result in throughput exceeding 95% of the treatment capacity, the permittee may, in lieu of initiating construction of the expansion, submit a report to the Division that demonstrates that the domestic wastewater treatment works was in compliance at all times during the events and that it is extremely unlikely that the event will reoccur.Where the permittee submits a report pursuant to unusual circumstances, and the Division, upon review of such report, determines in writing to the permittee that the report does not support the required findings, the permittee shall initiate planning and/or construction of the domestic wastewater treatment works as appropriate.PART IPage 8 of 36Permit No.: CO00202814. Facilities Operation and MaintenanceThe permittee shall at all times properly operate and maintain all facilities and systems of treatment and control including all portions of the collection system and lift stations owned by the permittee (and related appurtenances) which are installed or used by the permittee as necessary to achieve compliance with the conditions of this permit. Proper operation and maintenance also includes effective performance, and adequate laboratory and process controls, including appropriate quality assurance procedures. This provision requires the operation of back-up or auxiliary facilities or similar systems when installed by the permittee only when necessary to achieve compliance with the conditions of the permit.Any sludge produced at the wastewater treatment facility shall be disposed of in accordance with State and Federal regulations. The permittee shall take all reasonable steps to minimize or prevent any discharge of sludge use or disposal in violation of this permit which has a reasonable likelihood of adversely affecting human health or the environment. As necessary, accelerated or additional monitoring to determine the nature and impact of the noncomplying discharge is required.5. Acute WET Testing -Outfall(s): 001Aa. General Acute WET Testing and Reporting RequirementsThe permittee shall conduct an acute 48-hour WET test using Ceriodaphnia dubia and an acute 96-hour WET test using Pimephales promelas. Acute tests shall be conducted as a static replacement test using a single effluent grab sample. The permittee shall conduct each acute WET test in accordance with the 40 CFR Part 136 methods described in Methods for Measuring the Acute Toxicity of Effluents and Receiving Water to Freshwater and Marine Organisms, Fifth Edition, October 2002 (EPA-821-R-02-012) or its most current edition. The following specifications have been added to the acute WET method:Use of a CO2 atmosphere to control pH drift – The use of a CO2 atmosphere will be allowed to control ammonia toxicity due to pH drift. The proper methodology as outlined in the Acute Method must be followed and documented during the test. The permittee will be required to submit documentation showing that the proper methodology was used in the testing with the WET information summary that is submitted to the Division with the WET test results.The following minimum dilution series should be used: 0% effluent (control), 20%, 40%, 60%, 80%, and 100% effluent. If the permittee uses more dilutions than prescribed, and accelerated testing is to be performed, the same dilution series shall be used in the accelerated testing as was used in the failed test.Tests shall be done at the frequency listed in Part I.A.2. Test results shall be reported along with the Discharge Monitoring Report (DMR) submitted for the end of the reporting period when the sample was taken. (i.e., WET testing results for the calendar quarter ending March 31 shall be reported with the DMR due April 28, etc.) The permittee shall submit all laboratory statistical summary sheets, summaries of the determination of a valid, invalid or inconclusive test, and copies of the chain of custody forms, along with the DMR for the reporting period.If a test is considered invalid, the permittee is required to perform additional testing during the monitoring period to obtain a valid test result. Failure to obtain a valid test result during the monitoring period shall result in a violation of the permit for failure to monitor.b. Violations of the Permit Limit and Division NotificationAn acute WET test is failed whenever the LC50, which represents an estimate of the effluent concentration which is lethal to 50% of the test organisms in the time period prescribed by the test, is found to be less than or equal to 100% effluent. The permittee must provide written notification of the failure of a WET test to the Division, along with a statement as to whether accelerated testing or a Toxicity Identification Evaluation (TIE) is being performed, unless otherwise exempted, in writing, by the Division. Notification must be received by the Division within 14 calendar days of the permittee receiving notice of the WET testing results.PART IPage 9 of 36Permit No.: CO0020281c. Automatic Compliance ResponseThe permittee is responsible for implementing the automatic compliance response provisions of this permit when one of the following occurs: there is a violation of the permit limit (the LC50 endpoint is less than the applicable IWC) during a report-only period, when the LC50 endpoint is less than the applicable IWC the permittee is otherwise informed by the Division that a compliance response is necessaryWhen one of the above listed events occurs, the following automatic compliance response shall apply. The permittee shall either: conduct accelerated testing using the single species found to be more sensitive conduct a Toxicity Identification Evaluation / Toxicity Reduction Evaluation (TIE/TRE) investigationas described below.i. Accelerated TestingIf accelerated testing is being performed, testing will be at least once every two weeks for up to five tests, at the appropriate IWC, with only one test being run at a time. Accelerated testing shall continue until; 1) two consecutive tests fail or three of five tests fail, in which case a pattern of toxicity has been demonstrated or 2) two consecutive tests pass or three of five tests pass, in which case no pattern of toxicity has been found. Note that the same dilution series should be used in the accelerated testing as was used in the initial test(s) that result in the accelerated testing requirement.If no pattern of toxicity is found the toxicity episode is considered to be ended and routine testing is to resume. If a pattern of toxicity is found, a TIE/TRE investigation is to be performed. If a pattern of toxicity is not demonstrated but a significant level of erratic toxicity is found, the Division may require an increased frequency of routine monitoring or some other modified approach. The permittee shall provide written notification of the results within 14 calendar days of completion of the Pattern of Toxicity/No Toxicity demonstration.ii. Toxicity Identification Evaluation / Toxicity Reduction Evaluation (TIE/TRE)If a TIE/TRE is being performed, the results of the investigation are to be received by the Division within 180 calendar days of the demonstration of acute WET in the routine test, as defined above, or if accelerated testing was performed, the date the pattern of toxicity is demonstrated. A status report is to be provided to the Division at the 60 and 120 calendar day points of the TIE/TRE investigation. The Division may extend the time frame for investigation where reasonable justification exists. A request for an extension must be made in writing and received prior to the 180 calendar day deadline. Such request must include a justification and supporting data for such an extension.Under a TIE, the permittee may use the time for investigation to conduct a preliminary TIE (PTIE) or move directly into the TIE. A PTIE consists of a brief search for possible sources of WET, where a specific parameter(s) is reasonably suspected to have caused such toxicity, and could be identified more simply and cost effectively than a formal TIE. If the PTIE allows resolution of the WET incident, the TIE need not necessarily be conducted in its entirety. If, however, WET is not identified or resolved during the PTIE, the TIE must be conducted within the allowed 180 calendar day time frame.The Division recommends that the EPA guidance documents regarding TIEs be followed. If another method is to be used, this procedure should be submitted to the Division prior to initiating the TIE.If the pollutant(s) causing toxicity is/are identified, and is/are controlled by a permit effluent limitation(s), this permit may be modified upon request to adjust permit requirements regarding the automatic compliance response.PART IPage 10 of 36Permit No.: CO0020281If the pollutant(s) causing toxicity is/are identified, and is/are not controlled by a permit effluent limitation(s), the Division may develop limitations the parameter(s), and the permit may be reopened to include these limitations.If the pollutant causing toxicity is not able to be identified, or is unable to be specifically identified, or is not able to be controlled by an effluent limit, the permittee will be required to perform either item 1 or item 2 below.1) Conduct an investigation which demonstrates actual instream aquatic life conditions upstream and downstream of the discharge, or identify, for Division approval, and conduct an alternative investigation which demonstrates the actual instream impact. This should include WET testing and chemical analyses of the ambient water. Depending on the results of the study, the permittee may also be required to identify the control program necessary to eliminate the toxicity and its cost. Data collected may be presented to the WQCC for consideration at the next appropriate triennial review of the stream standards;2) Move to a TRE by identifying the necessary control program or activity and proceed with elimination of the toxicity so as to meet the WET effluent limit.If toxicity spontaneously disappears in the midst of a TIE, the permittee shall notify the Division within 10 calendar days of such disappearance. The Division may require the permittee to conduct accelerated testing to demonstrate that no pattern of toxicity exists, or may amend the permit to require an increased frequency of WET testing for some period of time. If no pattern of toxicity is demonstrated through the accelerated testing or the increased monitoring frequency, the toxicity incident response will be closed and normal WET testing shall resume.The control program developed during a TRE consists of the measures determined to be the most feasible to eliminate WET. This may happen through the identification of the toxicant(s) and then a control program aimed specifically at that toxicant(s) or through the identification of more general toxicant treatability processes. A control program is to be developed and submitted to the Division within 180 calendar days of beginning a TRE. Status reports on the TRE are to be provided to the Division at the 60 and 120 calendar day points of the TRE investigation.If toxicity spontaneously disappears in the midst of a TRE, the permittee shall notify the Division within 10 calendar days of such disappearance. The Division may require the permittee to conduct accelerated testing to demonstrate that no pattern of toxicity exists, or may amend the permit to require an increased frequency for some period of time. If no pattern of toxicity is demonstrated through the accelerated testing or the increased monitoring frequency, the toxicity incident response will be closed and normal WET testing shall resume.d. Toxicity ReopenerThis permit may be reopened and modified to include additional or modified numerical permit limitations, new or modified compliance response requirements, changes in the WET testing protocol, the addition of both acute and chronic WET requirements, or any other conditions related to the control of toxicants.6. Compliance Schedule(s)a. Activities to Meet Total Ammonia (December through April)– In order to meet the final limits, the followingschedule for construction (if deemed necessary by the permittee) are included in the permit.PART IPage 11 of 36Permit No.: CO0020281

b. Activities to Meet Dissolved Copper, Dissolved Cadmium, and Dissolved Zinc Final Limits – In order to meet the limitations, the following schedule are included in the permit.

All documents required by this compliance schedule (except permit modification applications) must be submitted to the Division accompanied by a fully completed “Permit Narrative Conditions Form” available at https://www.colorado.gov/pacific/cdphe/wq-permit-forms.Regulation 61.8(3)(n)(i) states that a report shall be submitted to the Division no later than 14 calendar days following each date identified in the schedule of compliance. The 14 days have already been incorporated into the above dates and therefore all reports are due on or before the date listed in the table.PART IPage 12 of 36Permit No.: CO00202817. Pretreatment Program - Industrial Waste Managementa. The Permittee has the responsibility to protect the Domestic Wastewater Treatment Works (DWTW), asdefined at section 25.8.103(5) of the Colorado Water Quality Control Act, or the Publicly-Owned TreatmentWorks (POTW), as defined at 40 CFR section 403.3(q) of the federal pretreatment regulations, frompollutants which would cause pass through or interference, as defined at 40 CFR 403.3(p) and (k), orotherwise be incompatible with operation of the treatment works including interference with the use ordisposal of municipal sludge.b. Pretreatment Standards (40 CFR Section 403.5) developed pursuant to Section 307 of the Federal CleanWater Act (the Act) require that the Permittee shall not allow, under any circumstances, the introductionof the following pollutants to the DWTW from any source of non-domestic discharge:i. Pollutants which create a fire or explosion hazard in the DWTW, including, but not limited to,wastestreams with a closed cup flashpoint of less than sixty (60) degrees Centigrade (140 degreesFahrenheit) using the test methods specified in 40 CFR Section 261.21;ii. Pollutants which will cause corrosive structural damage to the DWTW, but in no case discharges with apH of lower than 5.0 s.u., unless the treatment facilities are specifically designed to accommodate such discharges;iii. Solid or viscous pollutants in amounts which will cause obstruction to the flow in the DWTW, orotherwise interfere with the operation of the DWTW;iv. Any pollutant, including oxygen demanding pollutants (e.g., BOD), released in a discharge at a flowrate and/or pollutant concentration which will cause Interference with any treatment process at the DWTW;v. Heat in amounts which will inhibit biological activity in the DWTW resulting in Interference, but in nocase heat in such quantities that the temperature at the DWTW treatment plant exceeds forty (40)degrees Centigrade (104 degrees Fahrenheit) unless the Approval Authority, upon request of theDWTW, approves alternate temperature limits;vi. Petroleum oil, non-biodegradable cutting oil, or products of mineral oil origin in amounts that willcause Interference or Pass Through;vii. Pollutants which result in the presence of toxic gases, vapors, or fumes within the DWTW in a quantity that may cause acute worker health and safety problems;viii.Any trucked or hauled pollutants, except at discharge points designated by the DWTW; andix. Any specific pollutant that exceeds a local limitation established by the Permittee in accordance withthe requirements of 40 CFR Section 403.5(c) and (d).x. Any other pollutant which may cause Pass Through or Interference.c. EPA shall be the Approval Authority and the mailing address for all reporting and notifications to theApproval Authority shall be: USEPA 1595 Wynkoop St. 8ENF-W-NP, Denver, CO 80202-1129. Should theState be delegated authority to implement and enforce the Pretreatment Program in the future, thePermittee shall be notified of the delegation and the state permitting authority shall become the ApprovalAuthority.d. In addition to the general limitations expressed above, more specific Pretreatment Standards have beenand will be promulgated for specific industrial categories under Section 307 of the Act (40 CFR Part 405 et.seq.).PART IPage 13 of 36Permit No.: CO0020281e. The Permittee must notify the state permitting authority and the Approval Authority, of any newintroductions by new or existing industrial users or any substantial change in pollutants from any industrialuser within sixty (60) calendar days following the introduction or change. Such notice must identify:i. Any new introduction of pollutants into the DWTW from an industrial user which would be subject toSections 301, 306, or 307 of the Act if it were directly discharging those pollutants; orii. Any substantial change in the volume or character of pollutants being introduced into the DWTW by anyindustrial user;iii. For the purposes of this section, adequate notice shall include information on:(A) The identity of the industrial user;(B) The nature and concentration of pollutants in the discharge and the average and maximum flow of the discharge to be introduced into the DWTW; and(C) Any anticipated impact of the change on the quantity or quality of effluent to be discharged from or biosolids or sludge produced at such DWTW.iv. For the purposes of this section, a significant industrial user shall include:(A) Any discharger subject to Categorical Pretreatment Standards under Section 307 of the Actand 40 CFR chapter I and subchapter N;(B) Any discharger which has a process wastewater flow of 25,000 gallons or more per day;(C) Any discharger contributing five percent or more of the average dry weather hydraulic or organic capacity of the DWTW treatment plant;(D) Any discharger who is designated by the Approval Authority as having a reasonable potential for adversely affecting the DWTWs operation or for violating any Pretreatment Standard or requirements;f. At such time as a specific Pretreatment Standard or requirement becomes applicable to an industrial userof the Permittee, the state permitting authority and/or Approval Authority may, as appropriate:i. Amend the Permittee's NPDES discharge permit to require the Permittee to develop and submit anapprovable Pretreatment program under a compliance schedule, in accordance with procedures in40 CFR 403.8(e). The modification of a POTW's NPDES Permit for the purposes of incorporating a POTW Pretreatment Program approved in accordance with the procedure in §403.11 shall be deemed a minor Permit modification subject to the procedures in 40 CFR 122.63(g); or,;ii. Require the Permittee to specify, by ordinance, order, or other enforceable means, the type ofpollutant(s) and the maximum amount which may be discharged to the Permittee's DWTW for treatment. Such requirement shall be imposed in a manner consistent with the program development requirements of the General Pretreatment Regulations at 40 CFR Part 403; and/or,iii. Require the Permittee to monitor its discharge for any pollutant which may likely be discharged fromthe Permittee's DWTW, should the industrial user fail to properly pretreat its waste.The state permitting authority and the Approval Authority retains, at all times, the right to take legal action against any source of nondomestic discharge, whether directly or indirectly controlled by the Permittee, for violations of a permit, order or similar enforceable mechanism issued by the Permittee, violations of any Pretreatment Standard or requirement, or for failure to discharge at an acceptable level under national standards issued by EPA under 40 CFR, chapter I, subchapter N. In those cases where a CDPS permit violation has occurred because of the failure of the Permittee to properly develop and enforce Pretreatment Standards and requirements as necessary to protect the DWTW, the state permitting authority and/or Approval AuthorityPART IPage 14 of 36Permit No.: CO0020281shall hold the Permittee and/or industrial user responsible and may take legal action against the Permittee as well as the Industrial user(s) contributing to the permit violation.C. DEFINITION OF TERMS1. "Acute Toxicity" - The acute toxicity limitation is exceeded if the LC50 is at any effluent concentration lessthan or equal to the IWC indicated in this permit.1. “Antidegradation limits” – See “Two (2) - Year Rolling Average”.2. “Applicable water quality criterion (AWQC)” is the quantitation target level or goal. The AWQC may be one ofthe following:Where an effluent limit has been established,i. The AWQC is the effluent limit.Where an effluent limit has not been established, the AWQC may bei. An applicable technology based effluent limit (TBEL);

3. "Chronic toxicity", which includes lethality and growth or reproduction, occurs when the NOEC and IC25 are atan effluent concentration less than the IWC indicated in this permit.4. "Composite" sample is a minimum of four (4) grab samples collected at equally spaced two (2) hour intervalsand proportioned according to flow. For a SBR type treatment system, a composite sample is defined assampling equal aliquots during the beginning, middle and end of a decant period, for two consecutive periodsduring a day (if possible).5. "Continuous" measurement, is a measurement obtained from an automatic recording device which continuallymeasures the effluent for the parameter in question, or that provides measurements at specified intervals.6. "Daily Maximum limitation" for all parameters (except temperature, pH, dissolved oxygen, and WET) means thelimitation for this parameter shall be applied as an average of all samples collected in one calendar day. Forthese parameters the DMR shall include the highest of the daily averages. For pH and dissolved oxygen, thismeans an instantaneous maximum (and/or instantaneous minimum) value. For WET, this means aninstantaneous minimum value. The instantaneous value is defined as the analytical result of any individualsample. For pH and dissolved oxygen, DMRs shall include the maximum (and/or minimum) of all instantaneousvalues within the calendar month. For WET, DMRs shall include the minimum of all instantaneous values withinthe reporting period. For pH and dissolved oxygen, the value beyond the noted daily maximum limitation forthe indicated parameter shall be considered a violation of this permit. For temperature, see Daily MaximumTemperature. For WET violation and failure descriptions, see Part I.B.5.7. “Daily Maximum Temperature (DM)” is defined in the Basic Standards and Methodologies for Surface Water1002-31, as the highest two-hour average water temperature recorded during a given 24-hour period. This willbe determined using a rolling 2-hour maximum temperature. If data is collected every 15 minutes, a 2 hourmaximum can be determined on every data point after the initial 2 hours of collection. Note that the timeperiods that overlap days (Wednesday night to Thursday morning) do not matter as the reported value on theDMR is the greatest of all the 2-hour averages.This would continue throughout the course of a calendar day. The highest of these 2 hour averages over a month would be reported on the DMR as the daily maximum temperature. At the end/beginning of a month, the collected data should be used for the month that contains the greatest number of minutes in the 2-hour maximum.PART IPage 15 of 36Permit No.: CO00202818. "Dissolved (D) metals fraction" is defined in the Basic Standards and Methodologies for Surface Water 1002-31,as that portion of a water and suspended sediment sample which passed through a 0.40 or 0.45 UM (micron)membrane filter. Determinations of "dissolved" constituents are made using the filtrate. This may includesome very small (colloidal) suspended particles which passed through the membrane filter as well as theamount of substance present in true chemical solution.9. “Geometric mean” for E. coli bacteria concentrations, the thirty (30) day and seven (7) day averages shall bedetermined as the geometric mean of all samples collected in a thirty (30) day period and the geometric meanof all samples taken in a seven (7) consecutive day period respectively. The geometric mean may becalculated using two different methods. For the methods shown, a, b, c, d, etc. are individual sample results,and n is the total number of samples. Method 1:(1/n)Geometric Mean = (a*b*c*d*...) "*" - means multiplyMethod 2:Geometric Mean = antilog ( [log(a)+log(b)+log(c)+log(d)+...]/n )Graphical methods, even though they may also employ the use of logarithms, may introduce significant error and may not be used.In calculating the geometric mean, for those individual sample results that are reported by the analytical laboratory to be "less than" a numeric value, a value of 1 should be used in the calculations. If all individual analytical results for the month are reported to be less than numeric values, then report "less than" the largest of those numeric values on the monthly DMR. Otherwise, report the calculated value.For any individual analytical result of "too numerous to count" (TNTC), that analysis shall be considered to be invalid and another sample shall be promptly collected for analysis. If another sample cannot be collected within the same sampling period for which the invalid sample was collected (during the same month if monthly sampling is required, during the same week if weekly sampling is required, etc.), then the following procedures apply:i. A minimum of two samples shall be collected for coliform analysis within the next sampling period.

a letter noting that a result of TNTC was obtained for that period, and explain why another sample for that period had not been collected.If the sampling frequency is more frequent than monthly: Eliminate the result of TNTC from any further calculations, and use all the other results obtained within that month for reporting purposes. Attach a letter noting that a result of TNTC was obtained, and list all individual analytical results and corresponding sampling dates for that month.10. "Grab" sample, is a single "dip and take" sample so as to be representative of the parameter being monitored.11. “IC25” or “Inhibition Concentration” is a point estimate of the toxicant concentration that would cause a givenpercent reduction in a non-lethal biological measurement (e.g. growth or reproduction) calculated from acontinuous model (i.e. interpolation method). IC25 is a point estimate of the toxic concentration that wouldcause a 25-percent reduction in a non-lethal biological measurement.12. "In-situ" measurement is defined as a single reading, observation or measurement taken in the field at thepoint of discharge.13. "Instantaneous" measurement is a single reading, observation, or measurement performed on site using existingmonitoring facilities.PART IPage 16 of 36Permit No.: CO002028114. “LC50” or “Lethal Concentration” is the toxic or effluent concentration that would cause death in 50 percentof the test organisms over a specified period of time.15. “Maximum Weekly Average Temperature (MWAT)” is defined in the Basic Standards and Methodologies forSurface Water 1002-31, as an implementation statistic that is calculated from field monitoring data. TheMWAT is calculated as the largest mathematical mean of multiple, equally spaced, daily temperatures over aseven-day consecutive period, with a minimum of three data points spaced equally through the day. For lakesand reservoirs, the MWAT is assumed to be equivalent to the maximum WAT from at least three profilesdistributed throughout the growing season (generally July-September).The MWAT is calculated by averaging all temperature data points collected during a calendar day, and then averaging the daily average temperatures for 7 consecutive days. This 7 day averaging period is a rolling average, i.e. on the 8th day, the MWAT will be the averages of the daily averages of days 2-8. The value to be reported on the DMR is the highest of all the rolling 7-day averages throughout the month. For those days that are at the end/beginning of the month, the data shall be reported for the month that contains 4 of the 7 days.Day 1: Average of all temperature data collected during the calendar day. Day 2: Average of all temperature data collected during the calendar day. Day 3: Average of all temperature data collected during the calendar day. Day 4: Average of all temperature data collected during the calendar day. Day 5: Average of all temperature data collected during the calendar day. Day 6: Average of all temperature data collected during the calendar day. Day 7: Average of all temperature data collected during the calendar day.1st MWAT Calculation as average of previous 7 days Day 8: Average of all temperature data collected during the calendar day.2nd MWAT Calculation as average of previous 7 days Day 9: Average of all temperature data collected during the calendar day.3rd MWAT Calculation as average of previous 7 days16. “Minimum level (ML)” means the lowest concentration of an analyte that can be accurately and preciselyquantified using a given method, as determined by the laboratory.17. “NOEC” or “No-Observed-Effect-Concentration” is the highest concentration of toxicant to which organisms are exposed in a full life cycle or partial life cycle (short term) test, that causes no observable adverse effects on the test organisms (i.e. the highest concentration of toxicant in which the values for the observed responses are not statistically different from the controls). This value is used, along with other factors, to determine toxicity limits in permits.18. "Potentially dissolved (PD) metals fraction” is defined in the Basic Standards and Methodologies for Surface Water 1002-31, as that portion of a constituent measured from the filtrate of a water and suspended sediment sample that was first treated with nitric acid to a pH of 2 or less and let stand for 8 to 96 hours prior to sample filtration using a 0.40 or 0.45-UM (micron) membrane filter. Note the "potentially dissolved" method cannot be used where nitric acid will interfere with the analytical procedure used for the constituent measured.19. “Practical Quantitation Limit (PQL)” means the minimum concentration of an analyte (substance) that can be measured with a high degree of confidence that the analyte is present at or above that concentration. The use of PQL in this document may refer to those PQLs shown in Part I.D of this permit or the PQLs of an individual laboratory.20. "Quarterly measurement frequency" means samples may be collected at any time during the calendar quarter if a continual discharge occurs. If the discharge is intermittent, then samples shall be collected during the period that discharge occurs.21. "Recorder" requires the continuous operation of an automatic data retention device for providing requiredrecords such as a data logger, a chart and/or totalizer (or drinking water rotor meters or pump hour meterswhere previously approved.)22. SAR and Adjusted SAR - The equation for calculation of SAR-adj is:PART IPage 17 of 36Permit No.: CO00202812Ca MgNaSAR-adjxWhere:Na+ = Sodium in the effluent reported in meq/l Mg++ = Magnesium in the effluent reported in meq/lCax = calcium (in meq/l) in the effluent modified due to the ratio of bicarbonate to calciumThe values for sodium (Na+), calcium (Ca++), bicarbonate (HCO3-) and magnesium (Mg++) in this equation are expressed in units of milliequivalents per liter (meq/l). Generally, data for these parameters are reported in terms of mg/l, which must then be converted to calculate the SAR. The conversions are:meq/l = Equivalent weight in mg meqConcentration in mg l//Where the equivalent weights are determined based on the atomic weight of the element divided by the ion’s charge:Na+ = 23.0 mg/meq (atomic weight of 23, charge of 1) Ca++ = 20.0 mg/meq (atomic weight of 40.078, charge of 2) Mg++ = 12.15 mg/meq (atomic weight of 24.3, charge of 2) HCO3- = 61 mg/mep (atomic weight of 61, charge of 1)The EC and the HCO3 -/Ca++ ratio in the effluent (calculated by dividing the HCO3 - in meq/l by the Ca++ in meq/l) are used to determine the Cax using the following table.Table – Modified Calcium Determination for Adjusted Sodium Adsorption Ratio

PART IPage 18 of 36Permit No.: CO0020281

1 Adapted from Suarez (1981).2 Assumes a soil source of calcium from lime (CaCO3) or silicates; no precipitation of magnesium, and partial pressure of CO2 near the soil surface (PCO2) is 0.0007 atmospheres.3 Cax, HCO3, Ca are reported in meq/l; EC is in dS/m (deciSiemens per meter).Because values will not always be quantified at the exact EC or HCO3– /Ca++ ratio in the table, the resulting Cax must be determined based on the closest value to the calculated value. For example, for a calculated EC of 2.45 dS/m, the column for the EC of 2.0 would be used. However, for a calculated EC of 5.1, the corresponding column for the EC of 6.0 would be used. Similarly, for a HCO3– /Ca++ ratio of 25.1, the row for the 30 ratio would be used.The Division acknowledges that some effluents may have electrical conductivity levels that fall outside of this table, and others have bicarbonate to calcium ratios that fall outside this table. For example, some data reflect HCO3– /Ca++ ratios greater than 30 due to bicarbonate concentrations reported greater than 1000 mg/l versus calcium concentrations generally less than 10 mg/l (i.e., corresponding to HCO3– /Ca++ ratios greater than 100). Despite these high values exceeding the chart’s boundaries, it is noted that the higher the HCO3– /Ca++ ratio, the greater the SAR-adj. Thus, using the Cax values corresponding to the final row containing bicarbonate/calcium ratios of 30, the permittee will actually calculate an SAR-adj that is less than the value calculated if additional rows reflecting HCO3– /Ca++ ratios of greater than 100 were added.23. "Seven (7) day average" means, with the exception of fecal coliform or E. coli bacteria (see geometric mean), the arithmetic mean of all samples collected in a seven (7) consecutive day period. Such seven (7) day averages shall be calculated for all calendar weeks, which are defined as beginning on Sunday and ending on Saturday. If the calendar week overlaps two months (i.e. the Sunday is in one month and the Saturday in the following month), the seven (7) day average calculated for that calendar week shall be associated with the month that contains the Saturday. Samples may not be used for more than one (1) reporting period. (See the “Analytical and Sampling Methods for Monitoring and Reporting Section in Part I.D.5 for guidance on calculating averages and reporting analytical results that are less than the PQL).24. “Sufficiently sensitive test procedures”:i. An analytical method is ‘‘sufficiently sensitive’’ when the method detects and accurately andprecisely quantifies the amount of the analyte. In other words there is a valid positive result; ori. An analytical method is “sufficiently sensitive” when the method accurately and precisely quantifiesthe result to the AWQC, as demonstrated by the ML is less than or equal to the AWQC. In other words,the level of precision is adequate to inform decision making; orii. An analytical method is “sufficiently sensitive” when the method achieves the required level ofaccuracy and precision, as demonstrated by the ML is less than or equal to the PQL. In other words, the most sensitive method is being used and properly followed.25. "Thirty (30) day average" means, except for fecal coliform or E. coli bacteria (see geometric mean), thearithmetic mean of all samples collected during a thirty (30) consecutive-day period, which represents aPART IPage 19 of 36Permit No.: CO0020281calendar month. The permittee shall report the appropriate mean of all self-monitoring sample data collected during the calendar month on the Discharge Monitoring Reports. Samples shall not be used for more than one (1) reporting period. (See the “Analytical and Sampling Methods for Monitoring and Reporting Section in Part I.D.5 for guidance on calculating averages and reporting analytical results that are less than the PQL).26. Toxicity Identification Evaluation (TIE) is a set of site-specific procedures used to identify the specificchemical(s) causing effluent toxicity.27. “Total Inorganic Nitrogen (T.I.N.)” is an aggregate parameter determined based on ammonia, nitrate andnitrite concentrations. To determine T.I.N. concentrations, the facility must monitor for total ammonia andtotal nitrate plus nitrite (or nitrate and nitrite individually) on the same days. The calculated T.I.N.concentrations in mg/L shall then be determined as the sum of the analytical results of same-day sampling fortotal ammonia (as N) in mg/L, and total nitrate plus nitrite (as N) in mg/L (or nitrate as N and nitrite as Nindividually). From these calculated T.I.N. concentrations, the daily maximum and thirty (30) day averageconcentrations for T.I.N. shall be determined in the same manner as set out in the definitions for the dailymaximum and thirty (30) day average. (See the “Analytical and Sampling Methods for Monitoring andReporting Section in Part I.D.5 for guidance on calculating averages and reporting analytical results thatare less than the PQL).28. "Total Metals" means the concentration of metals determined on an unfiltered sample following vigorous digestion (Section 4.1.3), or the sum of the concentrations of metals in both the dissolved and suspended fractions, as described in Manual of Methods for Chemical Analysis of Water and Wastes, U.S. Environmental Protection Agency, March 1979, or its equivalent.29. “Total Recoverable Metals” means that portion of a water and suspended sediment sample measured by the total recoverable analytical procedure described in Methods for Chemical Analysis of Water and Wastes, U.S. Environmental Protection Agency, March 1979 or its equivalent.30. Toxicity Reduction Evaluation (TRE) is a site-specific study conducted in a step-wise process to identify the causative agents of effluent toxicity, isolate the source of toxicity, evaluate the effectiveness of toxicity control options, and then confirm the reduction in effluent toxicity after the control measures are put in place.31. "Twenty four (24) hour composite" sample is a combination of at least eight (8) sample aliquots of at least100 milliliters, collected at equally spaced intervals during the operating hours of a facility over a twenty-four (24) hour period. For volatile pollutants, aliquots must be combined in the laboratory immediately before analysis. The composite must be flow proportional; either the time interval between each aliquot or the volume of each aliquot must be proportional to either the wastewater or effluent flow at the time of sampling or the total wastewater or effluent flow since the collection of the previous aliquot. Aliquots may be collected manually or automatically.32. "Twice Monthly" monitoring frequency means that two samples shall be collected each calendar month onseparate weeks with at least one full week between the two sample dates. Also, there shall be at least onefull week between the second sample of a month and the first sample of the following month.33. “Two (2) -Year Rolling Average” (Antidegradation limits)- the average of all monthly average data collected ina two year period. Reporting of two-year rolling average results should begin in the first DMR due once thereporting requirements has been in place for a two year period. To calculate a two-year rolling average, addthe current monthly average to the previous 23 monthly averages and divide the total by 24. This methodologycontinues on a rolling basis as long as the two year rolling average reporting and/or effluent limit applies (i.e.,in the first reporting period use data from month 1 to month 24, in the second reporting period use data frommonth 2 to month 25, then month 3 to month 26, etc). Ongoing reporting is required across permit terms whendata is available for a two year period.34. "Visual" observation is observing the discharge to check for the presence of a visible sheen or floating oil.35. "Water Quality Control Division" or "Division" means the state Water Quality Control Division as established in25-8-101 et al.)Additional relevant definitions are found in the Colorado Water Quality Control Act, CRS §§ 25-8-101 et seq.,PART IPage 20 of 36Permit No.: CO0020281the Colorado Discharge Permit System Regulations, Regulation 61 (5 CCR 1002-61) and other applicable regulations.D. PERMIT SPECIFIC MONITORING, SAMPLING AND REPORTING REQUIREMENTS1. Routine Reporting of DataReporting of the data gathered in compliance with Part I.A or Part I.B shall be on a monthly basis. Reporting of all data gathered shall comply with the requirements of Part I.D. (General Requirements).Monitoring results shall be summarized for each calendar month via the division’s NetDMR service unless a waiver is granted in compliance with 40 CFR 127. If a waiver is granted, monitoring results shall be reported on division approved discharge monitoring report (DMR) forms (EPA form 3320-1).Reporting No Discharge:If no discharge occurs during the reporting period, a DMR must still be submitted. However, "No Discharge" shall be reported on the paper DMR and if reporting electronically please use the No Data Code (NODI) "C" for No Discharge in NetDMR.When submitting monitoring results via NetDMR, the Copy of Record shall reflect that the DMR was signed and submitted no later than the 28th day of the month following the reporting period. If submitting DMRs by mail, which is only allowed if a waiver has been granted, one copy of the DMR form shall be mailed to the division at the address provided below, so that the DMR is received no later than the 28th day of the month following the reporting period.If mailing, the original signed copy of each DMR shall be submitted to the division at the following address:Colorado Department of Public Health and Environment Water Quality Control DivisionWQCD-P-B24300 Cherry Creek Drive SouthDenver, Colorado 80246-1530The Discharge Monitoring Report paper and electronic forms shall be filled out accurately and completely in accordance with the requirements of this permit and the instructions on the forms; and signed by an authorized person as identified in Part II.K.1.2. Annual Biosolids ReportThe permittee shall provide the results of all biosolids monitoring and information on management practices, land application sites, site restrictions and certifications. Such information shall be provided no later than February 19th of each year. Reports shall be submitted addressing all such activities that occurred in the previous calendar year. If no biosolids were applied to the land during the reporting period, "no biosolids applied" shall be reported. Until further notice, biosolids monitoring results shall be reported on forms, or copies of forms, provided by the Division. Annual Biosolids Reports required herein, shall be signed and certified in accordance with the Signatory Requirements, Part I.D.1, and submitted as follows:The original copy of each form shall be submitted to the following address:COLORADO DEPARTMENT OF PUBLIC HEALTH AND ENVIRONMENT, WATER QUALITY CONTROL DIVISIONWQCD-PERMITS-B24300 CHERRY CREEK DRIVE SOUTHDENVER, COLORADO 80246-1530PART IPage 21 of 36Permit No.: CO0020281A copy of each form shall be submitted electronically or to the following address if any one of below conditions applies to this facility:1. design flow rate is equal to or greater than one million gallons per day,2. serves 10,000 people or more, or3. is required to have an approved pretreatment program.EPA BIOSOLIDS CENTER EPA REGION 7 WWPD/WENF11201 RENNER BOULEVARDLENEXA, KANSAS 66219ATTENTION: BIOSOLIDS PROGRAM MANAGER3. Representative SamplingSamples and measurements taken for the respective identified monitoring points as required herein shall be representative of the volume and nature of: 1) all influent wastes received at the facility, including septage, biosolids, etc.; 2) the monitored effluent discharged from the facility; and 3) biosolids produced at the facility. All samples shall be taken at the monitoring points specified in this permit and, unless otherwise specified, before the influent, effluent, or biosolids wastestream joins or is diluted by any other wastestream, body of water, or substance. Monitoring points shall not be changed without notification to and prior approval by the Division.4. Influent and Effluent Sampling PointsInfluent and effluent sampling points shall be so designed or modified so that: 1) a sample of the influent can be obtained after preliminary treatment and prior to primary or biological treatment and 2) a sample of the effluent can be obtained at a point after the final treatment process and prior to discharge to state waters. The permittee shall provide access to the Division to sample at these points.5. Analytical and Sampling Methods for Monitoring and ReportingThe permittee shall install, calibrate, use and maintain monitoring methods and equipment, including biological and indicated pollutant monitoring methods. All sampling shall be performed by the permittee according to specified methods in 40 C.F.R. Part 136; methods approved by EPA pursuant to 40 C.F.R. Part 136; or methods approved by the division in the absence of a method specified in or approved pursuant to 40 C.F.R. Part 136.The permittee may use an equivalent and acceptable alternative to an EPA-approved method without EPA review where the requirements of 40 CFR Part 136.6 are met and documented. The permittee may use an Alternative Test Procedure (ATP). An ATP is defined as a way in which an analyte is identified and quantified that is reviewed and approved by EPA in accordance with 40 CFR Part 136.4 for nationwide use, or a modification to a 40 CFR 136 approved method that is reviewed and approved by EPA in accordance with 40 CFR Part 136.5 for limited use.a. The permittee must select a test procedure that is “sufficiently sensitive” for all monitoring conducted inaccordance with this permit.b. The PQLs for specific parameters are listed in the table below.c. If the permit contains an interim effluent limitation (a limit is report until such time as a numeric effluentlimit becomes effective) for a parameter, the final numeric effluent limit shall be considered the AWQCfor the purpose of determining whether a test method is sufficiently sensitive.d. When the analytical method which complies with the above requirements has an ML greater than thepermit limit, and the permittee’s analytical result is less than the ML, the permittee shall report "BDL" onPART IPage 22 of 36Permit No.: CO0020281the DMR. Such reports will not be considered as violations of the permit limit, as long as the method is sufficiently sensitive. For parameters that have a report only limitation, and the permittee’s analytical result is less than the ML, (where X = the ML) “< X” shall be reported on the DMR.e. In the calculation of average concentrations (i.e. 7- day, 30-day average, 2-year rolling average) anyindividual analytical result that is less than the ML shall be considered to be zero for the calculationpurposes. When reporting:If all individual analytical results are less than the ML, the permittee shall report either “BDL” or “<X” (where X = the ML), following the guidance above.If one or more individual results is greater than the ML, an average shall be calculated and reported. Note that it does not matter if the final calculated average is greater or less than the ML, it must be reported as a value.Table Practical quantitation limits – Metals, inorganics, nutrients, radiological parameters, and nonylphenol

6. Flow Measuring DevicesUnless exempted in Part I.A of this permit, flow metering at the headworks shall be provided to give representative values of throughput and treatment of the wastewater system. The metering device shall be equipped with a local flow indication instrument and a flow indication-recording-totalization device suitable for providing permanent flow records, which should be in the plant control building.PART IPage 23 of 36Permit No.: CO0020281For mechanical facilities, where influent flow metering is not practical and the same results may be obtained from metering at the effluent end of the treatment facility, this type of flow metering arrangement will be considered, and if approved, noted in Part I.A of this permit. For lagoons, an instantaneous or continuous effluent flow measuring device shall be required in addition to the above described influent flow measuring device.At the request of the Division, the permittee must be able to show proof of the accuracy of any flow-measuring device used in obtaining data submitted in the monitoring report. The flow-measuring device must indicate values within ten (10) percent of the actual flow being measured.Permit, Part IIPage 24 of 36Permit No. CO0020281PART IIPart II contains standard conditions required by federal regulation to be included in all NPDES permits (see 40 C.F.R. 122.41). Part I contains permit specific requirements. To the extent that Part I conflicts with the standard terms and conditions of Part II, the requirements of Part I shall control.A. DUTY TO COMPLY1. The permittee must comply with all conditions of this permit. Any permit noncompliance constitutes a violationof the Colorado Water Quality Control Act and is grounds for: 1) enforcement action; 2) permit termination,revocation and reissuance, or modification; or 3) denial of a permit renewal application.2. Federal Enforcement:a. The permittee shall comply with effluent standards or prohibitions established under section 307(a)of the Clean Water Act for toxic pollutants and with standards for sewage sludge use or disposal (see 40 CFR 122.2) established under section 405(d) of the CWA within the time provided in the regulations that establish these standards or prohibitions or standards for sewage sludge use or disposal, even if the permit has not yet been modified to incorporate the requirement.b. The Clean Water Act provides that any person who violates section 301, 302, 306, 307, 308, 318 or405 of the Act, or any permit condition or limitation implementing any such sections in a permitissued under section 402, or any requirement imposed in a pretreatment program approved undersections 402(a)(3) or 402(b)(8) of the Act, is subject to a civil penalty not to exceed $25,000 per dayfor each violation. The Clean Water Act provides that any person who negligently violates sections301, 302, 306, 307, 308, 318, or 405 of the Act, or any condition or limitation implementing any ofsuch sections in a permit issued under section 402 of the Act, or any requirement imposed in apretreatment program approved under section 402(a)(3) or 402(b)(8) of the Act, is subject tocriminal penalties of $2,500 to $25,000 per day of violation, or imprisonment of not more than1 year, or both. In the case of a second or subsequent conviction for a negligent violation, a personshall be subject to criminal penalties of not more than $50,000 per day of violation, or byimprisonment of not more than 2 years, or both. Any person who knowingly violates such sections, orsuch conditions or limitations is subject to criminal penalties of $5,000 to $50,000 per day ofviolation, or imprisonment for not more than 3 years, or both. In the case of a second or subsequentconviction for a knowing violation, a person shall be subject to criminal penalties of not more than$100,000 per day of violation, or imprisonment of not more than 6 years, or both. Any person whoknowingly violates section 301, 302, 303, 306, 307, 308, 318 or 405 of the Act, or any permitcondition or limitation implementing any of such sections in a permit issued under section 402 of theAct, and who knows at that time that he thereby places another person in imminent danger of deathor serious bodily injury, shall, upon conviction, be subject to a fine of not more than $250,000 orimprisonment of not more than 15 years, or both. In the case of a second or subsequent convictionfor a knowing endangerment violation, a person shall be subject to a fine of not more than $500,000or by imprisonment of not more than 30 years, or both. An organization, as defined in section309(c)(3)(B)(iii) of the CWA, shall, upon conviction of violating the imminent danger provision, besubject to a fine of not more than $1,000,000 and can be fined up to $2,000,000 for second orsubsequent convictions.c. Any person may be assessed an administrative penalty by the Administrator for violating section 301,302, 306, 307, 308, 318 or 405 of this Act, or any permit condition or limitation implementing any ofsuch sections in a permit issued under section 402 of this Act. Administrative penalties for Class Iviolations are not to exceed $10,000 per violation, with the maximum amount of any Class I penaltyassessed not to exceed $25,000. Penalties for Class II violations are not to exceed $10,000 per day foreach day during which the violation continues, with the maximum amount of any Class II penalty notto exceed $125,000.B. DUTY TO REAPPLYIf the permittee plans to continue an activity regulated by this permit after the expiration date of this permit, the permittee must submit a permit application at least 180 days before this permit expires as required by Regulations 61.4 and 61.10.Permit, Part IIPage 25 of 36Permit No. CO0020281C. NEED TO HALT OR REDUCE ACTIVITY NOT A DEFENSEIt 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. DUTY TO MITIGATEThe permittee must take all reasonable steps to minimize or prevent any discharge or sludge use or disposal in violation of this permit which has a reasonable likelihood of adversely affecting human health or the environment.E. PROPER OPERATION AND MAINTENANCEThe permittee must at all times properly operate and maintain all facilities and systems of treatment and control (and related appurtenances) that 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 backup 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 this permit. See 40 C.F.R. §122.41(e).F. PERMIT ACTIONSThis permit may be modified, revoked and reissued, or terminated for cause. The filing of a request for a permit modification, revocation and reissuance, or termination, or a notification of planned changes or anticipated noncompliance does not stay any permit condition. Any request for modification, revocation, reissuance, or termination under this permit must comply with all terms and conditions of Regulation 61.8(8). See also 40 C.F.R. § 122.41(f).G. PROPERTY RIGHTSIn accordance with 40 CFR §122.41(g) and Regulation 61.8(9):1. The issuance of a permit does not convey any property or water rights in either real or personal property, orstream flows or any exclusive privilege.2. The issuance of a permit does not authorize any injury to person or property or any invasion of personal rights,nor does it authorize the infringement of federal, state, or local laws or regulations.3. Except for any toxic effluent standard or prohibition imposed under Section 307 of the Clean Water Act or anystandard for sewage sludge use or disposal under Section 405(d) of the Federal act, compliance with a permitduring its term constitutes compliance, for purposes of enforcement, with Sections 301, 302, 306, 318, 403,and 405(a) and (b) of the Clean Water Act. However, a permit may be modified, revoked and reissued, orterminated during its term for cause as set forth in Section 61.8(8) of the Colorado Discharge Permit SystemRegulations. See 61.8(9)(c).H. DUTY TO PROVIDE INFORMATIONThe permittee shall furnish to the Division, within a reasonable time, any information which the Division may request to determine whether cause exists for modifying, revoking and reissuing, or terminating this permit, or to determine compliance with this permit. The permittee shall also furnish to the Division, upon request, copies of records required to be kept by this permit in accordance with 40 C.F.R. §122.41(h) and/or Regulation 61.8(3)(q).I. INSPECTION AND ENTRYThe permittee shall allow the Division and the authorized representative, including U.S. EPA, and/or their authorized representatives (including an authorized contractor acting as their representative), upon the presentation of credentials as required by law, to conduct inspections in accordance with 40 C.F.R. §122.41(i), Regulation 61.8(3), and Regulation 61.8(4):Permit, Part IIPage 26 of 36Permit No. CO00202811. To enter upon the permittee's premises where a regulated facility or activity is located or conducted in whichany records are required to be kept under the terms and conditions of this permit;2. At reasonable times to have access to and copy any records required to be kept under the terms and conditionsof this permit and to inspect any facilities, equipment (including monitoring and control equipment), practices,operations or monitoring method regulated or required in the permit;3. To enter upon the permittee's premises in a reasonable manner and at a reasonable time to inspect orinvestigate, any actual, suspected, or potential source of water pollution, or to ascertain compliance ornoncompliance with the Colorado Water Quality Control Act or any other applicable state or federal statute orregulation or any order promulgated by the Division, and;4. Sample or monitor at reasonable times, for the purposes of assuring permit compliance or as otherwiseauthorized by the Clean Water Act, any substances or parameters at any location.J. MONITORING AND RECORDS1. Samples and measurements taken for the purpose of monitoring must be representative of the volume andnature of the monitored activity. See 40 C.F.R. § 122.41(j)(1).2. Monitoring must be conducted according to test procedures approved under 40 C.F.R. part 136 for theanalyses of pollutants unless another method is required under 40 C.F.R. subchapters N or O. In the case ofpollutants for which there are no approved methods under 40 C.F.R. part 136 or otherwise required under40 C.F.R. subchapters N or O, monitoring must be conducted according to a test procedure specified in thispermit for such pollutants. See 40 C.F.R. § 122.41(j)(4); 122.44(i)(1)(iv)(A).3. Except for records of monitoring information required by this permit related to the permittee's sewagesludge use and disposal activities, which shall be retained for a period of at least five years (or longer asrequired by 40 CFR part 503), the permittee shall retain records of all monitoring information, including allcalibration and maintenance records and all original strip chart recordings for continuous monitoringinstrumentation, copies of all reports required by this permit, and records of all data used to complete theapplication for this permit, for a period of at least 3 years from the date of the sample, measurement,report or application. This period of retention shall be extended during the course of any unresolvedlitigation regarding the discharge of pollutants by the permittee or when requested by the Division orRegional Administrator.4. Records of monitoring information must include:a. The date, exact place, and time of sampling or measurements;b. The individual(s) who performed the sampling or measurements;c. The date(s) analyses were performedd. The individual(s) who performed the analyses;e. The analytical techniques or methods used; andf. The results of such analyses.5. The permittee shall install, calibrate, use and maintain monitoring methods and equipment, includingbiological and indicated pollutant monitoring methods. See Regulation 61.8(4)(b)(iii). All sampling shall beperformed by the permittee according to sufficiently sensitive test procedures required by 40 C.F.R.122.44(i)(1)(iv) or methods approved by the Division, in the absence of a method specified in or approvedpursuant to 40 C.F.R. Part 136.6. The CWA provides that any person who falsifies, tampers with, or knowingly renders inaccurate any monitoringdevice or method required to be maintained under this permit shall, upon conviction, be punished by a fine ofnot more than $10,000, or by imprisonment for not more than 2 years, or both. If a conviction of a person is fora violation committed after a first conviction of such person under this paragraph, punishment is a fine of notmore than $20,000 per day of violation, or by imprisonment of not more than 4 years, or both.K. SIGNATORY REQUIREMENTSPermit, Part IIPage 27 of 36Permit No. CO00202811. Authorization to Sign: All documents required to be submitted to the Division by the permit must be signed inaccordance with 40 CFR §122.22, Regulation 61.4, and the following criteria:a. For a corporation: By a responsible corporate officer. For the purpose of this subsection, a responsiblecorporate officer means: (i) a president, treasurer, or vice president of the corporation in charge of aprincipal business function, or any other person who performs similar policy- or decision-makingfunctions for the corporation, or (ii) the manager of one or more manufacturing, production, oroperating facilities, provided, the manager is authorized to make management decisions which governthe operation of the regulated facility including having the explicit or implicit duty of making majorcapital investment recommendations, and initiating and directing other comprehensive measures toassure long term environmental compliance with environmental laws and regulations; the manager canensure that the necessary systems are established or actions taken to gather complete and accurateinformation for permit application requirements; and where authority to sign documents has beenassigned or delegated to the manager in accordance with corporate procedures.b. For a partnership or sole proprietorship: By a general partner or the proprietor, respectively; orc. For a municipality, state, federal, or other public agency: By either a principal executive officer orranking elected official. For purposes of this subsection, a principal executive officer of a federalagency includes (i) the chief or principal executive officer of the agency, or (ii) a senior executiveofficer having responsibility for the overall operations of a principal geographic unit of the agency.(e.g., Regional Administrator of EPA). For purposes of this section, a principal executive officer hasresponsibility for the overall operation of the facility from which the discharge originates.d. By a duly authorized representative in accordance with 40 C.F.R. 122.22(b), only if:i. the authorization is made in writing by a person described in Part II.K.1.a, b, or c above;ii. The authorization specifies either an individual or a position having responsibility for theoverall operation of the regulated facility or activity such as the position of plant manager, operator of a well or a well field, superintendent, position of equivalent responsibility, or an individual or position having overall responsibility for environmental matters for the company. (A duly authorized representative may thus be either a named individual or any individual occupying a named position); and,iii. The written authorization is submitted to the Division.2. Any person(s) signing documents required for submittal to the Division must 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.”3. The CWA provides that any person who knowingly makes any false statement, representation, or certificationin any record or other document submitted or required to be maintained under this permit, includingmonitoring reports or reports of compliance or non-compliance shall, upon conviction, be punished by a fine ofnot more than $10,000 per violation, or by imprisonment for not more than 6 months per violation, or by both.See 40 C.F.R. §122.41(k)(2).L. REPORTING REQUIREMENTS1. Planned Changes: The permittee shall give advance notice to the Division, in writing, of any planned physicalalterations or additions to the permitted facility in accordance with 40 CFR §122.41(l) and Regulation61.8(5)(a) and Part II.O. of this permit. Notice is required only when:a. The alteration or addition to a permitted facility may meet one of the criteria for determining whethera facility is a new source in 40 CFR §122.29(b); orb. The alteration or addition could significantly change the nature or increase the quantity of pollutantsdischarged. This notification applies to pollutants which are subject neither to effluent limitations inthe permit, nor to notification requirements under 40 CFR §122.41(a)(1).Permit, Part IIPage 28 of 36Permit No. CO0020281c. The alteration or addition results in a significant change in the permittee's sludge use or disposalpractices, and such alteration, addition, or change may justify the application of permit conditionsthat are different from or absent in the existing permit, including notification of additional use ordisposal sites not reported during the permit application process or not reported pursuant to anapproved land application plan. See 40 C.F.R. §122.41(l)(1)(iii).2. Anticipated Non-Compliance: The permittee shall give advance notice to the Division, in writing, of any planned changes in the permitted facility or activity that may result in noncompliance with permit requirements. The timing of notification requirements differs based on the type of non-compliance as described below.3. Transfer of Ownership or Control: The permittee shall notify the Division, in writing, thirty (30) calendar days in advance of a proposed transfer of the permit. This permit is not transferable to any person except after notice to the Division. The Division may require modification or revocation and reissuance of the permit to change the name of the permittee and incorporate such other requirements as may be necessary under the Clean Water Act. See Regulation 61.8(6); 40 C.F.R. §§ 122.41(l)(iii) and 122.61.4. Monitoring reports: Monitoring results must be reported at the intervals specified in this permit.a. If the permittee monitors any pollutant at the approved monitoring locations listed in Part I morefrequently than that required by this permit using test procedures approved under 40 CFR Part 136, oranother method required for an industry-specific waste stream under 40 CFR subchapters N or O, theresults of such monitoring shall be included in the calculation and reporting of the data submitted inthe DMR or sludge reporting form specified by the Division. See 40 CFR 122.41(l)(4).b. Calculations for all limitations which require averaging of measurements shall utilize an arithmeticmean unless otherwise specified by the Division in the permit.5. Submission of Discharge Monitoring Reports (DMRs): DMRs shall be submitted electronically through NetDMR system unless the permittee requests and is granted a waiver of the electronic reporting requirement by the Division pursuant to Regulation 61.8(4)(d).6. Compliance Schedules: Reports of compliance or noncompliance with, or any progress reports on, interim and final requirements contained in any compliance schedule in the permit, shall be submitted on the date listed in the compliance schedule section. The fourteen (14) calendar day provision in Regulation 61.8(4)(n)(i) has been incorporated into the due date.7. Twenty-four hour reporting:a. In addition to the reports required elsewhere in this permit, the permittee shall report the followingcircumstances orally within twenty-four (24) hours from the time the permittee becomes aware of thecircumstances, and shall mail to the Division a written report containing the information requestedwithin five (5) working days after becoming aware of the following circumstances:

any pollutant specifically identified as the method to control any toxic pollutant or hazardous substance.b. The report shall contain a description of the noncompliance and its cause; the period ofnoncompliance, including exact dates and times, and if the noncompliance has not been corrected, theanticipated time it is expected to continue; and steps taken or planned to reduce, eliminate, andprevent reoccurrence of the noncompliance.c. For noncompliance events related to combined sewer overflows, sanitary sewer overflows, or bypassevents, these reports must include the data described above (with the exception of time of discovery)as well as the type of event (combined sewer overflows, sanitary sewer overflows, or bypass events),Permit, Part IIPage 29 of 36Permit No. CO0020281type of sewer overflow structure (e.g., manhole, combine sewer overflow outfall), discharge volumes untreated by the treatment works treating domestic sewage, types of human health and environmental impacts of the sewer overflow event, and whether the noncompliance was related to wet weather. See 40 CFR 122.41(l)(6)(i).i. As of December 21, 2020 all reports related to combined sewer overflows, sanitary seweroverflows, or bypass events submitted in compliance with this section must be submittedelectronically by the permittee to the Director or initial recipient, as defined in 40 CFR127.2(b), in compliance with 40 CFR part 3 (including, in all cases, subpart D to part 3),§ 122.22, and 40 CFR part 127. See 40 CFR 122.41(l)(6)(i).8. Other non-compliance: A permittee must report all instances of noncompliance at the time monitoring reportsare due. These reports may be submitted annually in accordance with Regulation 61.8(4)(p) and/or 61.8(5)(f),but may be submitted at a more frequent interval.M. BYPASS1. Definitions:a. “Bypass” means the intentional diversion of waste streams from any portion of a treatment facility inaccordance with 40 CFR §122.41(m)(1)(i) and/or Regulation 61.2(12).b. Severe property damage means substantial physical damage to property, damage to the treatmentfacilities which causes them to become inoperable, or substantial and permanent loss of naturalresources which can reasonably be expected to occur in the absence of a bypass. Severe propertydamage does not mean economic loss caused by delays in production. See 40 CFR §122.41(m)(1)(ii).2. Bypass not exceeding limitations. The permittee may allow any bypass to occur which does not cause effluentlimitations to be exceeded, but only if it also is for essential maintenance to assure efficient operation. Thesebypasses are not subject to the provisions of 40 CFR 122.41(m)(3) and (m)(4). See 40 CFR §122.41(m)(2).3. Notice of bypass:a. Anticipated bypass. If the permittee knows in advance of the need for a bypass, the permittee shallsubmit prior notice, if possible, at least ten (10) days before the date of the bypass. See 40 CFR§122.41(m)(3)(i) and/or Regulation 61.9(5)(c).b. Unanticipated bypass. You must submit notice of an unanticipated bypass as required in Part II.L.7. Seealso 40 CFR §122.41(m)(3)(ii).4. Prohibition of Bypass: Bypasses are prohibited and the Division may take enforcement action against thepermittee for bypass, unless:a. the bypass is unavoidable to prevent loss of life, personal injury, or severe property damage;b. 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. Thiscondition is not satisfied if adequate backup equipment should have been installed in the exercise ofreasonable engineering judgment to prevent a bypass which occurred during normal periods ofequipment downtime or preventive maintenance; andc. Proper notices were submitted to the Division.i. The Division may approve an anticipated bypass, after considering its adverse effects, if the Division determines that it will meet the three conditions listed.N. UPSET1. Definition: “Upset” means an exceptional incident in which there is unintentional and temporarynoncompliance with technology based permit effluent limitations because of factors beyond the reasonablecontrol 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 preventative maintenance, orcareless or improper operation.See 40 CFR §122.41(n) and Regulation 61.2(114),Permit, Part IIPage 30 of 36Permit No. CO00202812. Effect of an upset: An upset constitutes an affirmative defense to an action brought for noncompliance withpermit effluent limitations if the requirements of section 3 are met. A determination made duringadministrative review of claims that noncompliance was caused by upset is final administrative action subjectto judicial review in accordance with Regulation 61.8(3)(j).**special note:** this provision is consistent with the definition of “Upset” as codified in Regulation 61.2(114). However, the Colorado regulatory definition of upset is less stringent than the federal code of regulations, which restricts the use of an upset defense to noncompliance with technology-based permit effluent limitations only. Colorado’s regulatory definition of bypass is less stringent than the requirements of the federal Clean Water Act.3. Conditions necessary for demonstration of an Upset: A permittee who wishes to establish the affirmativedefense of upset shall demonstrate through properly signed contemporaneous operating logs, or other relevantevidence that:a. an upset occurred and the permittee can identify the cause(s) of the upset;b. the permitted facility was at the time being properly maintained; andc. the permittee submitted notice of the upset as required in Part II.L.7 (24-hour notice); andd. The permittee complied with any remedial measure necessary to minimize or prevent any discharge orsludge use or disposal in violation of this permit which has a reasonable likelihood of adverselyaffecting human health or the environment. See also 40 C.F.R. 122.41(n)(3)(i)-(iv).**special note:** this provision is consistent with the definition of “Conditions necessary for demonstration of upset” as codified in Regulation 61.8(3)(j)(ii). However, the Colorado regulatory definition of upset is less stringent than the federal code of regulations, which restricts the use of an upset defense to demonstrate that a facility was properly operated and maintained. Colorado’s regulatory definition of “Conditions necessary for demonstration of upset” is less stringent than the requirements of the federal Clean Water Act.4. In addition to the demonstration required above, a permittee who wishes to establish the affirmative defenseof upset for a violation of effluent limitations based upon water quality standards shall also demonstratethrough monitoring, modeling or other methods that the relevant standards were achieved in the receivingwater.5. Burden of Proof: In any enforcement proceeding, the permittee seeking to establish the occurrence of anupset has the burden of proof.O. REOPENER CLAUSEProcedures for modification or revocation. Permit modification or revocation of this permit or coverage under this permit will be conducted according to Regulation 61.8(8). 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 of the following events occurs, including but not limited to:1. Water Quality Standards: The water quality standards of the receiving water(s) to which the permitteedischarges are modified in such a manner as to require different effluent limits than contained in this permit.2. Wasteload Allocation: A wasteload allocation is developed and approved by the State of Colorado and/or EPAfor incorporation in this permit.3. Discharger-specific variance: A variance is adopted by the Water Quality Control Commission.P. OTHER INFORMATIONWhen 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 in any report to the Division or U.S. EPA, the Discharger shall promptly submit such facts or information. See 40 C.F.R. § 122.41(l)(8).Permit, Part IIPage 31 of 36Permit No. CO0020281Q. SEVERABILITYThe provisions of this permit are severable. If any provisions or the application of any provision of this permit to any circumstances, is held invalid, the application of such provision to other circumstances and the application of the remainder of this permit shall not be affected.R. NOTIFICATION REQUIREMENTS1. Notification to Parties: All notification requirements shall be directed as follows:a. Oral Notifications, during normal business hours shall be to:CDPHE-Emergency Reporting Line: 1-877-518-5608; orWater Quality Protection Section – Compliance Program Water Quality Control DivisionTelephone: (303) 692-3500After hours notifications should be made to the CDPHE-Emergency Reporting Line: 1-877-518-5608.b. Written notification shall be to:Water Quality Protection Section – Compliance Program Water Quality Control DivisionColorado Department of Public Health and Environment WQCD-WQP-B24300 Cherry Creek Drive SouthDenver, CO 80246-1530S. RESPONSIBILITIESReduction, Loss, or Failure of Treatment Facility: The permittee has the duty to halt or reduce any activity if necessary to maintain compliance with the effluent limitations of the permit. It shall not be a defense for a permittee in an enforcement action that it would be necessary to halt or reduce the permitted activity in order to maintain compliance with the conditions of this permit.T. OIL AND HAZARDOUS SUBSTANCES LIABILITYNothing 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 to under Section 311 (Oil and Hazardous Substance Liability) of the Clean Water Act.U. EMERGENCY POWERSNothing in this permit shall be construed to preclude the institution of any legal action or relieve the permittee from any responsibilities, liabilities, or penalties established pursuant to any applicable State law or regulation under authority granted by Section 510 of the Clean Water Act. Nothing in this permit shall be construed to prevent or limit application of any emergency power of the Division.V. CONFIDENTIALITYAny information relating to any secret process, method of manufacture or production, or sales or marketing data which has been declared confidential by the permittee, and which may be acquired, ascertained, or discovered, whether in any sampling investigation, emergency investigation, Colorado Open Records Act (CORA) request, or otherwise, shall not be publicly disclosed by any member, officer, or employee of the Water Quality Control Commission or the Division, but shall be kept confidential. Any person seeking to invoke the protection of this section shall bear thePermit, Part IIPage 32 of 36Permit No. CO0020281burden of proving its applicability. This section shall never be interpreted as preventing full disclosure of effluent data.W. FEESThe permittee is required to submit payment of an annual fee as set forth in the 2016 amendments to the Water Quality Control Act. Section 25-8-502 (1.1) (b), and the Regulation 61.15 as amended. Failure to submit the required fee when due and payable is a violation of the permit and will result in enforcement action pursuant to Section 25-8-601 et. seq., C.R.S.1973 as amended.X. DURATION OF PERMITThe duration of a permit shall be for a fixed term and shall not exceed five (5) years. If the permittee desires to continue to discharge, a permit renewal application shall be submitted at least one hundred eighty (180) calendar days before this permit expires. Filing of a timely and complete application shall cause the expired permit to continue in force to the effective date of the new permit. The permit's duration may be extended only through administrative extensions and not through interim modifications. If the permittee anticipates there will be no discharge after the expiration date of this permit, the Division should be promptly notified so that it can terminate the permit in accordance with Regulation 61.Y. SECTION 307 TOXICSIf a toxic effluent standard or prohibition, including any applicable schedule of compliance specified, is established by regulation pursuant to Section 307 of the Clean Water Act for a toxic pollutant which is present in the permittee's discharge and such standard or prohibition is more stringent than any limitation upon such pollutant in the discharge permit, the Division shall institute proceedings to modify or revoke and reissue the permit to conform to the toxic effluent standard or prohibition.Permit, Part IIIPage 33 of 36Permit No. CO0020281PART III

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