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<br />Version 4/2/2019 Page - 8 Public Works Quote <br />c. Allow three (3) hours of contact time. <br />d. Work five (5)-foot sections of the bottom ten (10) feet of the upper screen with double disk for <br />a minimum of one (1) hour per five-foot section. <br />e. Pump off solution and neutralize any remaining acid with sodium bicarbonate. <br />f. Contractor is responsible for measuring and documenting the pH during pump off and <br />neutralizing any acid in the discharge. <br />g. Inject 110 gallons of sodium hypochlorite, combined with 2,000 gallons of clear water into <br />well using a 1,000 gallon cleaning tank, equipped with a pump, to inject the solution under <br />pressure through the double disk agitator. <br />h. Leave the chlorine solution in the well for a minimum of 36 hours contact time <br /> <br />10. Day 10 – Off site, 36 hour (min) contact time <br /> <br />11. Day 11 – Cleaning Top 10 feet of Upper Screen <br />a. Pump off chlorine solution to waste, neutralizing any remaining chlorine. <br />b. Inject 330 gallons of inhibited and stabilized hydrochloric acid and 3,500 gallons of clear <br />water into the well using a 1,000 gallon cleaning tank to mix in equal portions per tank, <br />equipped with a pump, to inject the solution under pressure. Work this solution into the top <br />ten feet of screen with double disk. <br />c. Allow three (3) hours of contact time. <br />d. Work five (5)-foot sections of the top ten (10) feet of the upper screen with double disk for a <br />minimum of one (1) hour per five-foot section. <br />e. Pump off solution and neutralize any remaining acid with sodium bicarbonate. <br />f. Contractor is responsible for measuring and documenting the pH during pump off and <br />neutralizing any acid in the discharge. <br />g. Inject 110 gallons of sodium hypochlorite, combined with 2,000 gallons of clear water into <br />well using a 1,000 gallon cleaning tank, equipped with a pump, to inject the solution under <br />pressure through the double disk agitator. <br />h. Leave the chlorine solution in the well for a minimum of 36 hours contact time. <br /> <br />12. Day 12 –Off site, 36 hour (min) contact time <br /> <br />13. Day 13 - Pump off to waste for thirty minutes, remove double disk agitator and test pump. Tear <br />down and clean up. <br /> <br />14. Payment for all work included in well cleaning shall be made as a lump sum as specified in the <br />proposal as follows: <br />Well Cleaning and Re-development……………………LS <br /> <br />XX. POST CLEANING VIDEO INSPECTION OF CASING AND SCREEN <br /> <br />A. Prevailing Specifications: None <br />B. Additions: <br />1. The complete well including casing and screen shall be video inspected with a color borehole <br />camera. <br />2. The well cannot be video inspected until a minimum of 24 hours after the test pump is pulled to <br />allow for debris to settle, allowing a clear view of the well. <br />3. It is the contractor’s responsibility to clear the well prior to the video if applicable. <br />4. Camera shall have sufficient lighting on board to show in plain view details within 16” well casing. <br />5. An archive copy of the video shall be provided to the customers on DVD with the pump inspection <br />report as well as a written summary of the inspection. <br />6. Borehole camera must have both down looking and side view/rotational capabilities. <br />7. Camera must have on screen display of depths overlaid directly to the video. <br />8. Submerged tape measures are not acceptable for documenting depth. <br />9. Black and white video, indirect mirror imaging, and low resolution cameras are not acceptable. <br />10. Payment for all work included in Post Cleaning Video Inspection of Casing and Screen shall be <br />made as a lump sum as specified in the proposal as follows: <br /> <br />Post Cleaning Video Inspection of Casing and Screen……………………LS