NPDES Permit No. MA0101168 Page 1 of 19 AUTHORIZATION TO DISCHARGE UNDER THE NATIONAL POLLUTANT DISCHARGE ELIMINATION SYSTEM In compliance with the provisions of the Federal Clean Water Act, as amended, [33 U.S.C. §§1251 et seq. (the "CWA")], and the Massachusetts Clean Waters Act, as amended, (MGL Chap. 21, §§26-53), Town of Palmer 4417 Main Street Palmer, MA 01069 is authorized to discharge from a facility located at: Palmer Water Pollution Control Facilities Norbell Street Three Rivers, Massachusetts 01080 and from six combined sewer overflows (CSOs) to receiving waters named: Chicopee River, Quaboag River (1 CSO), and Ware River (5 CSOs) in accordance with effluent limitations, monitoring requirements and other conditions set forth herein. This permit shall become effective on the first day of the calendar month immediately following 60 days after signature. This permit and the authorization to discharge expire at midnight, five (5) years from the last day of the month preceding the effective date. This permit supersedes the permit issued on September 29, 2000. This permit consists of 19 pages in Part I including effluent limitations, monitoring requirements, Attachments A (Discharge Outfall), B (Combined Sewer Overflows), C (Acute Toxicity Testing Protocol), D (left out intentionally), E (Industrial Pretreatment Program Annual Report), F (Reassessment of Technically Based Industrial Discharge Limits), G (Report Summary), and Part II including General Conditions and Definitions. Signed this 21st day of January, 2011 /S/SIGNATURE ON FILE ________________________ __________________________ Stephen S. Perkins, Director David Ferris, Director Office of Ecosystem Protection Massachusetts Wastewater Management Program Environmental Protection Agency Department of Environmental Protection Boston, MA Commonwealth of Massachusetts Boston, MA NPDES Permit No. MA0101168 Page 2 of 19 PART I A. EFFLUENT LIMITATIONS AND MONITORING REQUIREMENTS 1. Outfall 027 a. During the period beginning the effective date and lasting through expiration, the permittee is authorized to discharge treated effluent from outfall serial number 027 to the Chicopee River. Such discharge shall be limited and monitored by the permittee as specified below. Effluent Characteristic Units Discharge Limitation Monitoring Requirement *3 Parameter Average Average Maximum Measurement Sample Type*3 Monthly Weekly Daily Frequency Flow (Annual Average)*2 MGD 5.6 *2 — Report Continuous Recorder *2 Flow MGD Report — Report Continuous Recorder *4 5 BOD5 mg/l 30 45 Report 2/Week 24-Hour Composite* lbs/day 1400 2100 — 2/Week 24-Hour Composite*5 TSS *4 mg/l 30 45 Report 2/Week 24-Hour Composite*5 lbs/day 1400 2100 — 2/Week 24-Hour Composite*5 pH*1 Standard Units 6.0 – 8.3 SU (See Permit Part I.A.1.c.) 1/Day Grab (SU) Fecal Coliform Bacteria*1,* 6 cfu /100 ml 200 — 400 1/Week Grab (April 1 - Oct. 31) E. coli Bacteria*1, *6 cfu/100 ml 126 — 409 2/Week Grab (April 1 - Oct. 31) Total Residual Chlorine *1,*7, *8 mg/l 0.16 — 0.28 3/Day Grab (April 1 - Oct. 31) Copper, Total Recoverable ug/l 50.9 — 69.1 1/Month 24-Hour Composite*5 NPDES Permit No. MA0101168 Page 3 of 19 Part A.1.a. (Continued); Effluent Characteristic Units Discharge Limitation Monitoring Requirement Parameter Average Average Maximum Measurement Sample Type*3 Monthly Weekly Daily Frequency Total Nitrogen*9 mg/l Report — Report 1/Week 24-Hour Composite*5 Total Ammonia Nitrogen*10 mg/l Report — Report 1/Week 24-Hour Composite*5 Total Kjeldahl Nitrogen*10 mg/l Report — Report 1/Week 24-Hour Composite*5 Total Nitrate Nitrogen*10 mg/l Report — Report 1/Week 24-Hour Composite*5 Total Nitrite Nitrogen*10 mg/l Report — Report 1/Week 24-Hour Composite*5 Total Phosphorus (May 1 - Oct. 31) mg/l 1.0 2.0 — 2/Week 24-Hour Composite*5 Total Phosphorus (Nov 1 - April 30) *11 mg/l 1.0 — — 1/Month 24-Hour Composite*5 *15 5 Ortho-phosphorus, dissolved lbs/day Report — — 1/Month 24-Hour Composite* 5 (Nov 1-March 31) mg/l Report — — 1/Month 24-Hour Composite* *1, *12, *13, *14 5 Whole Effluent Toxicity % Acute LC50 > 100% 2/Year 24-Hour Composite* NPDES Permit No. MA0101168 Page 4 of 19 Footnotes: *1. Required for State Certification. *2. Report annual average, monthly average, and the maximum daily flow. The limit is an annual average, which shall be reported as a rolling average. The value will be calculated as the arithmetic mean of the monthly average flow for the reporting month and the monthly average flows of the eleven previous months. *3. A routine sampling program will be developed in which samples are taken at the same location, same time (or, within one hour of a set time) and same days of every month. Occasional deviations from the routine sampling program described above are allowed, but the reason for the deviation will be documented in correspondence appended to the applicable discharge monitoring report. All samples will be tested using the analytical methods found in 40 CFR § 136, or alternative methods approved by EPA in accordance with the procedures in 40 CFR § 136. All samples will be 24 hour composites unless specified as a grab sample in 40 CFR § 136. All required effluent samples shall be collected at the point specified herein. Any change in sampling location must be reviewed and approved in writing by EPA and MassDEP. PARAMETER: SAMPLE LOCATION: FLOW Recorder in the Effluent Flume FECAL, E-COLI and TOTAL After discharge from the chlorine contact chamber and CHLORINE RESIDUE dechlorination process, prior to discharge into the Chicopee River BOD5, TSS, pH RANGE, TOTAL After discharge from the chlorine contact chamber and AMMONIA AS N, TOTAL dechlorination process, prior to discharge into the Chicopee KJELDAHL NITROGEN, TOTAL River NITRITE, TOTAL NITRATE, and WHOLE EFFLUENT TOXICITY WET Dilution Water: Chicopee River Upstream of treated wastewater discharge outfall BOD and TSS (Influent) Influent line prior to primary tanks *4. Sampling is required for influent and effluent. *5. A 24-hour composite sample will consist of at least twenty four (24) grab samples taken during one consecutive 24 hour period, either collected at equal intervals and combined proportional to flow or continuously collected proportionally to flow. NPDES Permit No. MA0101168 Page 5 of 19 *6. Escherichia coli (E. coli) and fecal coliform bacteria limitations and monitoring requirements are effective from April 1st through October 31st. The monthly average limits are expressed as geometric means. The fecal coliform limitations and monitoring requirements will expire on October 31, 2011. The E. coli limitations and monitoring requirements will become effective on April 1, 2012. E. coli and fecal coliform bacteria samples will be collected concurrently with total residual chlorine samples. *7. Total residual chlorine limits and monitoring requirements are in effect from April 1st through October 31st. The permittee is not authorized to discharge chlorine from November 1st through March 31st. Each week, two of the total residual chlorine samples will be collected concurrently with the required E. coli bacteria samples. The minimum detection level (ML) for total residual chlorine (TRC) is defined as 0.02 mg/l. EPA defines the minimum level as the level at which the entire analytical system will give recognizable signal and calibration points. For total residual chlorine, this is the minimum level for chlorine using EPA-approved methods found in the most currently approved version of Standard Methods for the Examination of Water and Wastewater, Method 4500 CL-E and G, or USEPA Manual of Methods of Analysis of Water and Wastewater, Method 330.5. One of these methods must be used to determine total residual chlorine. For effluent limitations less than 0.02 mg/l, compliance/non-compliance will be determined based on the ML. Sample results of 0.02 mg/l or less shall be reported as zero on the discharge monitoring report (DMR). For every day that more than three TRC samples are analyzed, the monthly DMR will include an attachment documenting the individual grab sample results for that day, the date and time each sample was collected, the analytical method used, and a summary of any operational modifications implemented in response to the sample results. This requirement applies to all samples taken, including screening level and process control samples. All test results using an EPA-approved analytical method will be used in the calculation and reporting of the monthly average and maximum daily data submitted on the DMR (see Part II Section D.1.d.(2)). *8. Chlorination and dechlorination systems shall include an alarm system on or before April 1, 2011 for indicating system interruptions or malfunctions. Any interruption or malfunction of the chlorine dosing system that may have resulted in levels of chlorine that were inadequate for achieving effective disinfection or interruptions or malfunctions of the dechlorination system that may have resulted in excessive levels of chlorine in the final effluent shall be reported with the monthly DMRs. The report shall include the date and time of the interruption or malfunction, the nature of the problem, and the estimated amount of time that the reduced levels of chlorine or dechlorination chemicals occurred. *9. See Part I.B, Special Conditions, for requirements to evaluate and implement optimization of nitrogen removal. Once per month Nitrogen sampling will be required until July 1, 2011. Once per week Nitrogen sampling will be required beginning the week of July 3, 2011. *10. Total ammonia nitrogen, total Kjeldahl nitrogen, nitrite nitrogen, and nitrate nitrogen samples shall be collected concurrently. Once per month Nitrogen sampling will be required until July 1, 2011. Once per week Nitrogen sampling will be required beginning the week of July 3, 2011. NPDES Permit No. MA0101168 Page 6 of 19 *11.