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Parametrix Comments 001~ ____ November 21, 2007 PMX No. 247-1781-024 Mr. Jim Gibson, P.E. City of Yelm 105 Yetm Avenue West Yelm, WA 98599 Re: Forester Heights Water Booster Pump Sta[ioq Sewnd Review Dear Mr. Gibson: We have completed review of the design submittal by KPFP for the Forrester Heights Booster Pump Station received in our of£tce November 5, 2002 The submittal included a revised Water Booster Pump Station dated October 22, 2007 (Engineer's Seal Date), full size design drawings dated October 22, 2007 (Engineer's Seal Date), and a Washington State Department of Health Project Approval Application Form (undated). We have [he following comments and recommendations based on our review: COMMENTS 1. Revise the building and/or piping layout to allow ndequate operator access to the pump skid, service panel, and control panel. In the current configuratioq an operator would have to step over above-slab piping including a pressure release valve and hose bib [o access the panels. Provide a minimum of 2 feet of clearance on all sides of the pump skid. Please note that some of the comments and recommendations in this letter will change the dimensions otthe proposed equipment. 2. Revise the line types used for the in-building piping on Sheet Cl l.l. Drawings show dashed tines for above-slab piping and [he pressure tank. 3. As previously noted, indicate the type of joint restraint for the piping connecling the existing LO-inch water main to the booster pump assembly, i.e. flanged connections, mechanical joint with megalug etc. 4. As previously noted, provide a check valve on the discharge side of each pump. The appropriate type of check valve should be determined based on [he wn[er hammer analysis noted below. 5. Provide a hose rack on [he wall in the vicinity of the hose bib. 6. Provide a lifting strategy for removal of large equipment such as the pumps and bladder tank. 7. Provide an air gap for the drain line from the pressure relief valve per DOH standards. Mr. Jim Gibson November 21, 2007 Page 2 8. Draw the generator to scale in [he plan view, including the enclosure. Provide a minimum of 3 feet of clearance from the building and fencing to allow maintenance and fueling of the generator. Provide a detail of the generator mounting slab. 9. The plans and project report indicate a 35 kW generator will be provided, while [he equipment specifications indicate 40 kW. Once all comments that could impact power requirements have been addressed, provide load calculations to size the generator. 10. Provide the optional foam and sound scoop noise attenuation options on the generator. 11. Provide HVAC calculations to verify the exhaust fan and heater selection. Verify that the 24-inch-diameter gable vents will allow adequate airflow to enter the building. 12. Provide calculations (not estimates) of [he fitting losses and head losses through the booster pump station [o verify pump selection is correct Include the losses through [he check valves requested in [his letter. 13. Perforzn a water hammer analysis on the lift station and proposed Fortes[er Heights water distribution system. The analysis should specifically address fire hydrant and system valve operation, normal pump starts and stops, and pump stops due [o power outage. 14. Provide bladder tank sizing calculations. Provide two smaller bladder tanks for redundancy. 15. As previously requested, provide a detailed control and instrumentation plan and control logic. Describe the specific instrumentation and control components proposed for use in the system. I6. The plans indicate that the electrical systems will be bidder-designed. As previously noted, a detailed electrical design must be provided [o review adequacy of the system prior to approval of this project. 17. The electrical system will require review once the mechanical comments have been addressed. General electrical comments ere: • Clarify [he type of enclosures to be used for the control panel and transfer switch. • Provide a minimum of 3 feet of clearance in front of the control panel and transfer switch. • Provide weatherproof receptacles inside [he pump station. l8. The Maintenance Chart included iu the project report includes references to a well, well house, end reservoir. Provide a project-specific maintenance chart. 19. Has the DOH Project Approval Application Form been submitted yet? If so, provide all DOH comments with the next submittal package. Once these comments have beeu addressed and the additional information requested has been provided, we can provide a more detailed review of the proposed pump station. Mr. Jim Gibson November 21, 2007 Page 3 • As previously noted, it appears that the pumps [he applicant is proposing will meet the minimum operating pressures required to respond to peak demands (30 psi residual pressure) and fire flow demands (20 psi residual pressure). However, we would recommend that the City/applicant review the minimum operating pressures that the booster stafion is sized for and consider increasing the expected operating pressure to exceed minimum DOH requirements. Specifically, we recommend [hat the system be designed to meet the 60 psi average residual pressure generally available throughout the City of Yelm during peak hourly demand conditions. • We recommend that [he City consider inclusion of a water meter on the discharge of the booster station • As previously noted, we recommend that the wntrol system for the booster pump station be tied into the overall City SCADA system. The proposed visual and auditory alarm is not sufficient to ensure adequate response to problems with the pump station. This effort may need to be completed by the City or the Ciry's agent. To facilitate continued progress in the review of [his project, we recommend a meeting including [he City of Yelm, Parametrix, the applicant, and the applicant's engineer to further discuss these comments and recommendations. Please contact either of us if yon would like to schedule this meeting. If we can be of further assistance, please le[ us know. Thank you for the opportuniTy to review this project for you. Very truly yours, ~~ Ra y Ray ond, P.E. Senior Engineer, Municipal Services Group Very tmly yours, PA~RAME'fRIX M` ichae~iv~ ~ R Water Solutions Program Manager RR:MTO:Ie cc: Project File