Specifications include, but are not limited to: Chemical treatment and redevelopment of Field Well #2 located at Berlin State Fish Hatchery. 1st Treatment – Once the pumping equipment has been removed the CONTRACTOR shall pre-treat the well by jetting the interior of the screen with a high pressure stream of water to remove soft materials and break apart hardened mineral deposits from the screen surface. The jetting tool is to be set within the well along with either a submersible or centrifugal pump. Once set, the jetting tool will be raised and lowered through the well screen covering the entire length of screen on each pass. Throughout the jetting process, the submersible/centrifugal pump will be used to pump debris loosened out of the well. Waste water pumped from the well will be directed to a temporary holding tank where the solids will we allowed to settle out prior to discharge of the water on-site at a location acceptable to the OWNER. 2nd Treatment - Upon removal of the jetting equipment, the surge-block development tools will be set, and prior to the placement of any chemicals, the well will be surged for a period of one (1) hour and then pumped to waste to remove any loose debris from the interior of the screen & casing. Place in the well screen a solution consisting of 20 degree baume Muriatic Acid and NuWell 310 Bio-Acid Enhancer. A sufficient amount of Acid shall be placed in the well to provide an Acid concentration in the entire screen and gravel pack of 15%. The NuWell 310 shall be added at a rate of 2.5 gallons per 55 gallons of Acid. Once the solution has been placed in the well it shall be forced into the formation by the addition of 1,500 gallons of potable water. The Acid/NW310 solution shall then be surged, pumped and backwashed for a minimum of 4 hours. The high volume backwash effort shall include the recirculation of unspent Acid/NW310 solution into the well through the developing tools. Each backwash event should include a quantity of not less than 1,000 gallons of the chemical solution being forced back into the screened section of the well. Once the treatment is complete, the well will be pumped to waste while surging, into the temporary settling tank provided by the CONTRACTOR. After settlement, the Acid solution will be neutralized to a pH of at least 6.0 by the addition of Soda Ash, and then discharged to waste on-site at the location designated by the OWNER. A detailed record of the neutralization data shall be maintained and submitted with the final report. In calculating the amount of chemicals to be required, the screen length plus 5' shall be considered as a base. The gravel pack shall be considered to have a porosity of 50% and allowance should be made to fill both the screen and the gravel pack with chemicals.
