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HomeMy WebLinkAbout10-09-2000MINUTES OF THE SANITARY SEWER BOARD OF THE CITY OF JEFFERSONVILLE October 9, 2000 The Sanitary Sewer Board of the City of Jeffersonville met in regular session in the Mayor's Conference Room in the City County Building, Jeffersonville, Indiana on the 28th day of September 2000. Mayor Tom Galligan, with Secretary Treasurer Peggy Wilder at the desk, called the meeting to order at 4:05 PM. Board Members Jefferey Caldwell and Jack Jordan were also in attendance. The Mayor asked if there were any changes to be made to the agenda. Being none, the agenda was approved unanimously. Secretary Treasurer Wilder informed the Board of changes to the minutes of September 11th and September 25th. A motion to approve the minutes with the changes was made by Jack Jordan, seconded by Jeffery Caldwell, carded unanimously. The claims were presented to the Board for approval. After a brief discussion, Jeffery Caldwell made a motion to approve the claims, seconded by Jack Jordan, passing unanimously. Report on Delinquent Accounts Gelsena Smith, Director of Sewage Billingo went over the report of delinquent accounts. Ms. Smith informed the Board that the outstanding delinquent accounts were down to $387,895.53. She said that September 2000 monthly collections were $500,995.93, a record amount for the year. Mayor Galligan told Ms. Smith that he would like to put a lien on the commercial accounts immediately. Jeffery Caldwell made a motion that the property owners owing over $2,000 be contacted and given a final deadline before the liens were placed. ARer a discussion, Mr. Caldwell amended his motion that the property liens be made immediately, seconded by Jack Jordan, carrying unanimously. The Board then went over delinquencies over $1,000, and the Mayor made a motion to give those property owners a deadline for payment with notification required by State Law before a lien will be placed on those properties, seconded by Jack Jordan. The motion passed 2-0, with Jeffery Caldwell abstaining. Construction and Plan Project Report John Toombs asked if the Board members received their copies of the reports, and told them he would be happy to answer any questions. A general discussion was had regarding improvements and project updates. Mr. Toombs also updated the Board on the Pleasant Run Project. Because of conflicts with property owners, the lift station was moved. Two change orders regarding this project were presented to the Board. Mr. Toombs discussed two Change Orders with the Board. He said that one change had to do with the distance of the pump, and the pump would be required to be bigger. That requires more electricity, more excavation and the increase of length in the forced main itself. The change would also require paving, road repair and traffic. An Air relief valve was also added because the main will be placed over a hill· The cost with the changes is $275,630.70· Jack Jordan made a motion to accept these Change Orders, seconded by Jeffe~ Caldwell, passing unanimously. WWTP Operations Report Summary,, EMC Ray Wilkey, EMC, went over the operational reports presented to the Board. He noted that things had gone smoothly for the month, with the exception of a problem with Wyandott. The DAF unit went down, causing direct discharge to the plant. The company will be charged for the discharge. He also went over the sewer lines that had been cleaned, and the number of calls taken from consumers. A general discussion was had regarding other activities for the month. Cost Savings Estimate, EMC Jim Traylor, EMC, went over the cost savings report presented to the Board. He estimates the savings to be $2,716,220 over the period of May 1994 to April 2000. The savings could have been greater, but the customer base and employee benefits have affected those costs. WWTP Operations Report Summary,, PEH Mark Sneve, PEH Engineers, addressed the report given out at the last meeting and would like to know if the Board had any questions. Mr. Jordan told him the report was well documented and he had no questions. Mr. Sneve then handed out a summary report of treatment plant operations, and went over all the items listed on that report with the Board. A general discussion was had regarding these projects and project updates. RFQ for Statement of Qualifications Jack Jordan would like to continue this until all current engineering contracts have been reviewed. Mill Creek Pump Station Capital Repair Request Ray Wilkey, EMC, has turned in a request for the MII~L creek Pump Station Capital Repair. During recent inspections it was noted that the volute housing wear was excessive. The cost of repair parts has been estimated to be $9,147.66. The cost ora new pump is $13,808.00. Mr. Wilkey recommends repairing the pump instead of replacing it. EMC would like the Board to accept the quote from Spencer Machine and Tool Company. The Board had a discussion regarding the project, and had questions in regards to how long the Pumps would last. The long- term plan on the project is to replace the pumps, and put drywall submersibles and VFD's in these stations. Mr. Wilkey told the Board that it was necessary to make the repair as soon as possible. Mayor Galligan said that grease inspections would continue until the City found out who was responsible for dumping grease into the system illegally. Jack Jordan made a motion to approve the repair in the amount of $9,147.66, seconded by Jeffery Caldwell, passing unanimously. Member ATTEST: Mayor Tom Galligan, tive Clerk Tre~s~a~er Peggy W~ der [] Information Only [] Project Specific [] Policy Memo---File With MEMORANDUM TO: FROM: DATE: RE: Thomas R. Galligan, Mayor and Jeffersonville Sewer Board Mark A. Sneve, October 18, 2000 Review of EMC Operations - September 2000 We have completed our monthly review of EMC's operations. The purpose of our review was to evaluate plant data and operation strategies to verify that EMC is operating the wastewater treatment plant in the best interest of the City of Jeffersonville. To complete our review of the September operation, we have reviewed the following: · Current contract between EMC and the City of Jeffersonville; · EMC's DMR and MOR for September 2000 (received by email 10/17). PEH Engineers visited the WWTP several times during September and discussed conditions with EMC during the month. Our review focused on EMC's monthly operation report (MOR). We have produced four pages of graphs from the monthly data provided (consistent with past monthly reviews). · WWTP Loadings: The first page presents influent mass loadings and influent flows compared to design values. O Influent BOD loadings are averaging 58% of design loading (10,581 lb/d). However the plant received a spike in loading on September 25, likely due to suspension of settled matter during a rainfall event. The plant assimilated the spike in loading without violation of BOD effluent limits. O The TSS loading averaged about 66% of design (10,105 lb/d). The WWTP received the same spike in loading for TSS as for BOD on 9/25, again the likely consequence of a rain event. The spike in loading did not result in a high effluent TSS. O The influent ammonia graph shows daily, 7-day, and 28-day moving average mass loadings. There is no present design loading for your wastewater treatment plant to make comparisons. The influent ammonia loading fluctuated between 21.5 and 709 lb/d with a monthly average of 430 lb/d. The plant assimilated the variability in loadings throughout the month without violation of effluent ammonia limits. O The influent flow is approximated by effluent flow measurement. Effluent flow measurement has been shown to be erroneous due to design considerations. Since the final clarifier failed in September 1999, the peak flow capacity of the WWTP is 17.1 mgd and the peak sustained flow capacity is 12 mgd. The monthly average flow was measured to be 78% of capacity of the plant (5.2 mgd). The peak daily flow reached 9.44 mgd, still below the "rated" capacity of 1.2 mgd with one clarifier out of service. G:\SDATA\@PEHk901--950\944X002\WRDEReview of EMC Operations - Sep, 2000 memo.doc\10.18.00 Page 2 October 18, 2000 · Effluent Quality: The second page of graphs show the plant performance for effluent CBOD, TSS, and ammonia compared to the weekly average and monthly average effluent limits. The 7~day moving average (MVA) effluent concentration is used to compare to the weekly permit limit and 28-day moving average effluent limit was used to compare to the monthly average effluent limit. The WWTP did not violate an,/permit limits durin~ September. · Effluent CBOD concentrations were well below permit limits · Effluent TSS concentrations were well below permit limits. ® Effluent NH3-N concentrations were well below permit limits. · Activated Sludge Process: The third page of graphs shows typical activated sludge parameters. O The first graph shows the food to mass of volatile organisms (F:Mv) ratio. For extended aeration activated sludge wastewater treatment plants, the target F:Mv is typically between 0.08 and 0.10. The activated sludge plant averaged 0.07 during September, an acceptable value. O The next graph shows the sludge volume index (SVI). SVI is an indicator of settleability of mixed liquor. SVIs below 150 are not cause for concern. SVI above 150 suggests poor settling characteristics. For the entire month, the SVI continued to be well below 100. EMC maintains the capability to enhance settling by polymer addition during days with high flows and poor settling. O The next graph shows the organic loading rate for the oxidation ditch activated sludge process. Your activated sludge process was designed with an OLR of 15 lb. BOD/day/1000 cf. The running average OLR varied between 6.4 and 10.2 throughout the month with individually higher and lower daily values. This is within a reasonable range. O The next graph includes the solids loading rate (SLR), a measure of the mass of solids in the influent to the clarifiers. "Ten States Standards" limits the solids loading rate to less than 35 lb/d/sf of clarifier surface area. The chart shows the daily, 7 day MVA and 28 day MVA SLR. Based on improving settling and lower flows, EMC has been operating only two final clarifiers since June 10. The clarifier SLR has been averaging 2i to 26 lb/d/sf with daily peaks of 34 lb/d/sf. I have included a chart that shows the daily SVI ' and SLR data versus the curve from WEF MOP 8. The chart demonstrates improved performance since all data points are well below the curve. EMC has some minor control over the mass of solids going to the final clarifiers through the MLSS concentration and RAS pump rate. They have been lowering the MLSS (to reduce SLR), and have been reducing the RAS pumping rate to a practical minimum based on removing sludge from the clarffier mechanisms. EMC has reported concerns over the RAS flowmeters and suggest the measured flows are not accurate. Based on our review of the RAS daily data (flow and concentration), we agree the flow measurements do not make sense after about July 10. We have not modified the daily data for the sake of this report. If the data is wrong, the only parameter impacted is the Solids Loading Rate. Replacement sludge flow meters are being designed. O The next plot is for mixed liquor suspended solids (MLSS in mg/L). The MLSS concentration of the activated sludge plant varied between 2,000 - 3,500 m~JL averaging about 2,700 mg/L. Typically MLSS ranges from 2,500 to 4,500 mg/L for the extended G:\SDATA\@PEI-B901--950\944\002\WRDXReview of EMC Operations - Sep, 2000 memo.doc\10.18.00 Page 3 October 18, 2000 aeration process. EMC no longer targets a MLSS concentration to control the process; they now target a constant sludge age. O The next graph shows the mixed liquor volatile suspended solids 0MLVSS in IVELVSS has been averaging between 1,300 and 2,300 m~?_fL. This range is reasonable. The MLVSS shows the same trending as the MLSS graph. O The next graph shows the yield of solids from the activated sludge process. The yield is defined as the pounds of TSS produced per pound of BOD removed. For an extended aeration activated sludge plant, a yield between 0.8 and 1.0 is reasonable. Your plant had an average yield of 1.0. We have averaged out the effect of non-uniform wasting of sludge in the calculation of yield. O The last graph shows the Sludge Age, a measure of the average time a microorganism spends in the activated sludge system. We recommended in our proposal that the activated sludge process be operated to maintain a constant sludge age rather than a constant MLSS. A sludge age of 20 to 25 days is typical. Your plant had an average sludge age of 22 days in September. EMC .currently targets a constant sludge age of 22 days. In summary, the activated sludge process is performing well (BOD and NH3-N removal) including SVIs which have stabilized at an excellent level. The process is stable now, however EMC should continue to employ steps such as polymer addition as a contingency (EMC has polymer feed equipment on standby during wet weather). EMC should also continue daily microscopic evaluation of the activated sludge floc. We recommend adding an anoxic zone preceding the oxidation ditch to improve the poor settleability of the sludge observed in early 2000. Such a tank could be added during a major reconstruction process, due to the need to disrupt process flow. In the interim, EMC may be able to operate aerators at low speed for times to create anoxic conditions; this should be initiated with great caution as evidenced by the increasing effluent CBOD concentrations when attempted in mid-July. EMC had several samples analyzed for nitrate in the effluent in early summer of 2000. Results suggest there is less than 0.5 m~L of nitrate remaining in the effluent, which is impractical. A more reasonable nitrate concentration is 5 to 20 m~?JL. EMC obtained additional data on effluent nitrate concentrations. The results show effluent nitrate between 2 and 4 rog/L, which suggests substantial denitrification is occurring within the oxidation ditch. EMC will continue to collect more data to determine if denitrification varies seasonally. PEH assisted EMC with collection of ORP data at various locations in the plant. ORP is a measure of the oxidation/reduction potential. The ORP value can indicate the oxic state of the process (anaerobic-anoxic-aerobic) and can be used as a process control tool. The ORP readings obtained to date suggest aerobic conditions dominate in the activated sludge process. EMCs ORP probe broke in June and no additional data has been collected. EMC received their new probe recently and began collecting data again. Data collection with the new probe shows generally aerobic conditions predominate throughout the plant. EMC will continue to collect ORP data weekly. G:\SDATA\@PEI~901--950\944\002\WRDW-eview of EMC Operations - Sep, 2000 memo.doc\10.18.00 Page 4 October 18, 2000 I asked Ray Wilkey of EMC if they had made use of the process tracking spreadsheet I had sent in June. They have explored the spreadsheet and plan to use the spreadsheet to trend their process. EMCs Concerns according to their letter dated October 13, 2000: Sludae Flow Meters - EMC indicates their loss of confidence in the RAS, WAS and other sludge transfer flow meters. I discuss the recommended replacement of these meters in a separate letter dated August 28, 2000. PEH has agreed to prepare plans and specifications for replacement of Doppler type sludge flow meters with magnetic type sludge flow meters. PEH is proceeding with preparation of plans and specifications for the replacement of these meters. We anticipate these plans and specs to be ready by the beginning of November. Lift Station VFD Specifications - EMC recommends the city add ViZ'Ds to the main lift stations to better match pumping rate to influent and reduce .the surges in flow presently delivered to the WWTP. EMC is working with JTL on installation of VFDs. Lift Station Standard Specifications - '~MC is working with JTL on preparation of standard specifications. PEH will review the proposed standards when available. Dumpin~ Pad at the WWTP - City crews are working On this project which is almost complete. Clarifier Painting - The painting contractor has been hired to paint Clarifier No. 2 mechanism when the repair is complete by Smith Contractors. SCADA Systerr! - EMC and Donohue are working on this project. They anticipate submitting draft plans and specs for PEH's review soon. Lawn Mowers - EMC requested purchase of two lawnmowers to allow plant staff to maintain the grounds in lieu of subcontracting. One mower will be furnished from the Parks Department; an additional mower can be borrowed from the parks department if necessary. Other Items: Plant valve vault. Bob Miller is starting on this project. He has Ordered the valve vault and lids. Liftstation upgrades. EMC had a meeting on October 13 with JTL to review the Ewing Lane lift station. The station will either be upgraded or replaced. cc: Jorge Lanz, JTL Attachments 2-944.002/CS G:\SDATA\@PEH\90t--950\944\002\WRD~.eview of EMC Operations - Sep, 2000 memo.doc\10.18.00 Jeffer~onviile WWTP PEH Engineers Influent BOD, Ib/d vs. Design Loading I Daily 7 d MVA 28 d MVA ' ~" Design Loading 2O0O 4000 0 Influent TSS, Ib/d vs. Design Loading I ,Daily 7 d MVA 28 d MVA ~ = Desgn Loading 24000 12000 ~ 8000 4000 0 1000 Influent NH3-N, Ib/d I Daity '7 d MVA 28 d MVA i 600 400 -- Influent Flow, mgd vs. Design Flow F Daily 7dMVA 28dMVA = -- DesgnFlow 4.00 0.00 Jeffplantdata-0900.xls 10/17/00 'l/§ u~ 'GO~O o o ~oooo ~/6w ~OOGO q/§~ 'N-SHN 0 0 0 ~ 0'") ('~ lAS 0 0