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Parametrix Comments 002V3I PRPAR AVF.N[IP. ru. uox aw SI:MNER WASHISG]'Vti 9N'g1i14 T. 2Si. 84i S6B P. 253. %3.0'l46 rv wpa~ sunF.wm December 10, 2007 PMX No. 247-1781-024 Mr. ]im Gibson, P.E. City of Yelm 105 Yelm Avenue West Yclm, WA 98597 Rc: Forrester Heights Wa[cr Booster Pump Sm[iou, Second Review Comments Dear Mr. Gibson: On November 21, 2007, we provided comments and recommendations based on review of the design submittal by KPFP For the Forrester Heights Booster Pump Station received in our office November 5, 2007. 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). After meeting with City of Yelm staff on December 4, 2007, we are providing the following comments, which incorporate our previous review as well as City staff comments to be addressed prior to approval of [he booster station plans: I. Design [he system to provide domestic service at the 60 psi nominal average residual pressure generally available throughout the Ciry of Yelm during peak hourly demand conditions. Fire service shall meet the 20 psi residual required by DOH. 2. The plaus indicate that [he booster station will be located in a utility easement. The City requires fee ownership of the booster station site. The parcel size shall extend, at a minimum, [o the fence line as described in this letter. 3. Revise the building and/or piping layout to allow adequate operator access to the pump skid, s'crvice panel, and control panel. In the curtenl configuration, an upcmlor would have to step over above-slab piping, including a pressure release valve and hose bib, to access the panels. Provide a minimum of 2 feet oC clearance on all sides of the pump skid. Please note that some of the comments and rccommcudations in this letter will change the dimensions of the proposed equipment. 4. Provide a 6-foot chain link fence around [he entire booster station. Locate the fence a minimum oC 5 tees from the building footprint and generator pad. Provide a 12-foot double-leaf gate centered on the driveway at the front of the building and a 3-foot man gate a[ the back. 5. Sheet CI 1.0 shows 6-inch piping connecting [o the 8-inch pump skid manifold. Provide inlet and outlet piping [o match the manifold. The only pipe size transitions shall be at the connections to the existing 10-inch water main stubs. Mr. Jim Gibson December 10, 2007 Page 2 6. Revise the line types used for the io-building piping on Sheet CI L1. Drawings show dashed lines for above-slab piping and [he pressure tank. 7. Provide flanged connections on all above-slab piping in [he building. Provide mechanical joint fittings with [hms[ blocks and megalugs for all below-ground piping. Specifically indicate the f ding and join[ restrain[ types in [he Equipment List on Sheet CI 1.0. 8. Provide a check valve on the discharge side of each pump. The appropriate type of check valve should be determined based on the water hammer analysis noted below. 9. Provide a ball valve curb stop at the tee For the hose bib. 10. Provide e hose rack on [he wall in the vicinity of the hose bib. I I. Slope the Floor slab of the booster station building such [ha[ all areas will drain toward the doors. 12. Provide a lifting strategy for removal of large equipment such as [he pumps and bladder tank. 13. Provide an air gap for the drain line from The pressure relief valve per DOH standards. 14. The plans and project report indicate a 35 kW generator will be provided, while the equipment specifications indicate 40 kW. Once all comments that could impact power requirements have been addressed, provide load calculations to size [he gcneramr. I5. Draw the generator to scale in the plan view, including the enclosure. Provide a minimum of 3 feet of clearance from the building to allow maintenance and fueling of Hie generator. Provide a detail of the generator mounting slab. 16. Provide the optional foam and sound swop noise attenuation options on the generator. 17. 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. 18. Provide calculations (no[ estimates) of the fining losses and head losses through the booster station to verify pump selection is' correct. Include the los's'es' through the check valves requested in this letter. 19. Perform a water hammer analysis on the booster station and proposed Forrester Heights water distribution system. The analysis should specifically addres's' fire hydrant and system valve operation, normal pump starts and stops', and pump stops due to power outage. 20. Provide bladder tank sizing calculations. Provide two smaller bladder tanks for redundancy. 21. As previously requested, provide a detailed control and instrumentation plan and control logic. Describe the specific instmmentation and control components proposed for use in the system. Provide variable frequency drives (VFDs) for all pumps. In the control logic, include the capability to periodically alternate which pump serves as Icad for providing domestic Flows. 22. The plans indicate that the electrical systems will be bidder-designed. As previously noted, a detailed electrical design must be provided to review adequacy of [he system prior to approval of this project. Mr. Jim Gibson December 10, 2007 Page 3 23. The electrical system will require review once [he mechanical comments have been addressed. General electrical comments are: • 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 the booster siatton. 24. The developer shall provide the equipment necessary to facilitate connection of the booster station to the City's SCADA system. Specifically, provide a new Remote Terminal Unit (RTU) built by Taums Controls based on a Rockwell Micrologix 1500 similar to [he Water System Wcll House unit Provide an Input/Output Q/O) list for the control of new booster pumps, monitoring of the pressure instrument, monitoring of the emergency generator, and an intrusion door switch to Taurus Controls to allow the system to he customized to this~ecific zpplicaticn. Ncte that this project will require coordination between the electrical design and Taurus Controls including instmments, booster pump controls, and other features. The I/O list provides a major part of this coordination link. A Parametrix technician will verify that the City's radio SCADA system has coverage at the booster station site. 25. The maintenance chart included in the project report includes references to a well, well house, and reservoir. Provide aproject-specific maintenance chart. 26. The City will require a double check valve backtlow assembly (DCVA) on each water service served by [he booster station to prevent draining of residential plumbing in [he event of a water main break. 27. Provide all DOH comments provided in response to the Project Approval Application Form with the next submittal package. 28. Installation of a meter on the discharge side of the booster station was considered, but was determined to be unnecessary due [o the small area and limited number of residences served by the station. However, the City will generally require a meter installed in awordance with City Standards on future water booster stations. Once these comments have been addressed and the additional information requested has been provided, we can complete our review of [he proposed booster station. If we can be of further assistance, please le[ us know. Thank yon for [he opportunity t ~ is p or you. Very truly your, 'I'yP~1~I4RAM ~TRIX / 1 J ~j~ Ran~ond, P.E. tchael T. Ollivant,~- Senior Engineer, Municipal Services Group Water Solutions Program Manager RR:nkd ce: Project File