Revised_SOW_Yose_Valley_Well_2_Rehab_Amd0005_0005.pdf

STATEMENT OF WORK

URGENT REHAB OF WELL #2 IN YOSEMITE VALLEY

Objective:

Yosemite Valley Utilities needs a Professional Deep Well Specialist to pull well pump, assess repairs needed and replace spider bearings at well pump, approximately 187 feet below grade.

Background:

Well #2 is located in Yosemite Valley at an elevation of 4000’. This well produces up to 1000 gallons per minute (GPM). The well depth is approximately 970 feet with the pump sitting at approximately 187 feet. The shafts are shaking/wobbling and making noises. This well operates at 1760 RPMs and over the years the glacial silt has been pulled through the impellers and spider bearings causing pitting and excessive wear to the packing gland, impellers, head shaft and spider bearings, resulting in higher amp readings, reduced production and an inability to control water spray from the packing box assembly.

Scope of Work:

1. Remove motor and base from the well column.

2. Provide equipment and personnel to pull turbine pump set at approximately 187’ depth.

There is a skylight/roof access to pull the shaft from the building.

3. After pulling the shaft and pump, assess conditions of all components below grade and refurbish as necessary, to include T&C column pipe water lube, 1-1/2” water lube shaft assembly (shaft, sleeve, coupling, retainer and bearing). Shafts and T&C column pipes are in 10’ lengths. It is expected the spider bearings and other bolts will need replacement.

4. It is possible the well casing (187’) and PVC pipe for level transducer sounding tube may need to be replaced due to age and glacial silt damage. Replacement of well casing and level transducer sounding tube should be included in the bid.

5. Verify that the repairs will not exceed the scope or award amount of the purchase order. If the necessary repairs will exceed the purchase order amount, or if repairs are not possible, notify the contracting officer in writing before proceeding with any further work.

6. After repairs are made, re-install all components and adjust shaft to optimum impeller clearance.

7. Vendor shall remain onsite while NPS personnel initiate start up procedures to verify production of water from pump, amperage is adequate to turn impellers, and shaft is stable in place.

8. All work must be done in compliance with AWWA C654-03 (or most recent), sections 4.4,

4.5 and 4.5.1 for disinfection of well and well equipment.

Delivery:

Well #2 is in Yosemite Valley at an elevation of approximately 4000’ and weather conditions can change without warning. The well is located behind Yosemite Lodge on uneven, unpaved road with muddy conditions possible. There is a 45’ vehicle length restriction on Highway 140. All work must be performed during park hours 7am-5pm, no weekend or holiday work permitted without written permission, NPS representative will always be onsite. Work shall be completed within 5 days of notice to proceed.

Contact: Jerod Raines, Valley Utilities Supervisor, 209-347-1510 tmodjeski Cross-Out