Attach_D_Well_Scope_Clarification.docx

Solicitation No. G14PS00535 USGS Patuxent Wildlife Research Center Water and Sewer Improvements in Coburn and Endangered Species Area Patuxent Water and Sewer Scope of Work Clarification and Addendum:

Coburn Area:

Well #5: Pump and pitless adapter were replaced with new units on January 11, 2012. A new pump will be needed to meet the proposed pump head conditions. Contractor shall provide and install the new pump and power cable as specified. Existing drop pipe may be utilized unless damaged by Contractor. Pump column shall be replaced with 2” PVC Shur Align or equal or Galvanized steel drop pipe. A single check valve shall be placed on the pump discharge. New pump power and control wiring shall be provided along with pump control panel. Pump depth settings are as follows: 140’ below grade surface. Contractor shall provide new water service lines and electrical power connection from the existing Well #5 to the new Coburn Treatment Building. Refer to attached Well Test Report for data.

Well #13: Pump, motor, wire, and drop pipe were replaced with new units on January 30, 2012. A new pump will be needed to meet the proposed pump head conditions. Contractor shall provide and install the new pump and power cable as specified. Existing drop pipe may be utilized unless damaged by Contractor. Pump column shall be replaced with 2” PVC Shur Align or equal or Galvanized steel drop pipe. A single check valve shall be placed on the pump discharge. New pump power and control wiring shall be provided along with pump control panel. Pump depth settings are as follows: 140’ below grade surface. Contractor shall provide new water service lines and electrical power connection from the existing Well #13 to the new Coburn Treatment Building. Refer to attached Well Test Report for data.

Well # 19: Contractor shall drill and develop a new well with all equipment and appurtenances. Criteria for New Well #19 shall be assumed for bidding purposes to be the same as Well No. 13 with 2” PVC Shur Align or equal or Galvanized Steel drop pipe and pump curve as shown on drawing PM-4. Construction details shall be as shown in Typical Well Installation Detail on drawing PM-5 including pitless adapter, power and control wiring and check valve. Connect new water service and electrical power from new well site to new Coburn Treatment Building.

Drawing PM-4: Well No. 13 Pump Curve Change: “Well No. 13 Pump Curve” diagram title To Read: “Well Nos. 13 and 19 Pump Curve”

Drawing PM-4; Coburn Area Well Design Parameters:

Change: “Well #13: 100 GPM at 375’ TDH ITT Goulds Model 150H15-6” To Read: “Well #13 and #19: 100 GPM at 375’ TDH ITT Goulds Model 150H15-6”

Endangered Species Area:

Well #6: Contractor shall abandon existing well in accordance with Maryland State Regulations. Contractor shall remove existing pump, motor, all equipment and appurtenances. Refer to attached Well Test Report for data.

Well #7: A new pump will be needed to meet the proposed pump head conditions. Contractor shall provide and install the new pump and power cable as specified. Existing drop pipe may be utilized unless damaged. Pump column shall be replaced with 2” PVC Shur Align or equal or Galvanized steel drop pipe. A single check valve shall be placed on the pump discharge. New pump power and control wiring shall be provided along with pump control panel. Pump depth settings are as follows: 210’ below grade surface. Contractor shall provide new water service lines and electrical power connection from the existing Well #7 to the new Well #7 Tank Building. Refer to attached Well Test Report for data.

Well # 14; Existing well, pump, motor and all appurtenances to remain as-is; construct a new electrical power generator, transfer switch and associated appurtenances.

Well # 18: Contractor shall drill and develop a new well with all equipment and appurtenances. Criteria for New Well #18 shall be assumed for bidding purposes to be the same as the criteria for existing Well #7; with 4” PVC Shur Align or equal or Galvanized Steel drop pipe and pump curve as shown on drawing PM-2. Construction details shall be as shown in Typical Well Installation Detail on drawing PM-5 including pitless adapter, power and control wiring and check valve. Connect new water service and electrical power from the new well site to new Well #18 Tank Building.

G15PS00053

Attachment D Well Scope Clarification