SITE INFORMATION AND CORRESPONDENCE_FILE 1

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November 6, 1992 Clark Well, Inc. Page -2- Police Facility Emergency Well 3 . Unbolt, cut, and remove the steel grate over the well. 4. Remove an 18 inch square section of the concrete floor around the top of the well. Remove the top 2 feet of well casing. 5. Perforate the well casing from -100 feet to -2 feet with 'a mills knife or other approved perforating device. Perforations shall consist of one row per foot with each row having four slots. Each slot shall have an approximate width and length of 3/16" x 4" respectively. Unless otherwise submitted and approved, run the perforator on solid tools , to ensure its proper placement and position in the well. 6. Backfill from -183 feet to the bottom of the concrete basement floor with cement grout. Install a tremie pipe to within 20 feet of the bottom of the well. Pump cement slurry through the tremie pipe up to the specified depth in one continuous operation. Remove the tremie pipe as the cementing operation continues, however, keep the bottom of the pipe submerged in the slurry throughout the filling procedure. Once the level reaches the top of the well casing, place a temporary cover/seal at the well surface which will permit pressurization of the well casing interior. Pressurize the casing interior to 25 psi for a period of at least 15 minutes. At the end of the 15 minute period add the necessary amount of cement required to bring the level up until it completely fills and overtops the remaining well casing, creating a grout cap on the casing. Let the grout set for at least 12 hours. Additional grout required due to pressurization and/or settlement shall be included in the bid price. The cementing material for the cement grout shall conform to API Class A cement. The mixture shall be either neat cement or a slurry of cement-sand grout composed of no more than 1 part sand to 1 part cement. The water to cement ratio of shall be no more than 5.2 gal per 94 lb sack of cement. The cement mixture density shall be no less than 118 lb/cubic ft. Bentonite, to make the mix more fluid and reduce shrinkage, shall be added at a rate of four (4) percent of the volume of cement. Water used in the cement shall be clean, potable water. 7. Pour new concrete, with a cement strength of at least a six- sack mix, into the 18 inch square section and finish to match the existing floor.