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INSTALLATION INSTRUCTIONS: UNDER GROUND UTILITY WORK AND EXCAVATION IS A SPECIALIZED TYPE OF CONSTRUCTION AND THESE INSTRUCTIONS CANNOT BE SUBSTITUTED FOR SKILL AND EXPERIENCE. USE ONLY EXPERIENCED UNDERGROUND UTILITY CONTRACTORS. OFF LOADING AND SETTING: Fiberglass wet wells are to be lifted by forks, slings or"chokers" and not by chains or cables. During off loading and installation the wet well is to be protected from sudden drops or impacts with hard objects. Wet wells should not be rolled. Lifting lugs are provided for 72" diameter or wet wells over 12 ft deep- contractor shall use a spreader bar for handling larger wet wells. EXCAVATION: CONTRACTOR MUST FOLLOW ALL OSHA GUIDELINES RELATING TO EXCAVATION, SHEETING, SHORING AND TRENCH SAFETY. WETWELL MUST BE SET IN A "DRY' HOLE ON STABILIZED SOIL. INSTALLATION of ANCHORAGE andIPLACEMENT (stabilized bedding required for all methods) There are many methods of installation 'or engineer may direct specific instructions for jobsite conditions. All methods require water (or mechanical forces) to be added to wet well to prevent floatation and bracing or sheeting to prevent shifting of the wetwell. All of these methods utilize the anti-float flange on the wetwell bottom as an embedment in the concrete Recommended method: direct bury of wetwell-compacted area must be larger than the wetwell Step 1) Bottom of excavation must be graded and have a compacted sub-base-either native soil or rock bedding- use 6" of compacted rock or stone where native soil must be undercut or removed. Step 2) Concrete to be placed on the floor of the excavation, then the wetwell is set onto the wet concrete, the concrete pour is continued around the anti-float flange, utilizing the excavation walls as a "form" to insure that the concrete is in contact with the anti-float flange and wall of the wetwell. Another acceptable method of installation is the use of bricks or blocks to hold the bottom of the wetwell up off the ground, which allows the wet concrete to flow under the bottom for full contact. Alternate method: Concrete base- built on site- engineer may direct the wetwell anti-float flange to be imbedded into a concrete base to form a "pre-cast concrete" hold down pad. Pad shall have lift hooks so the pad is lifted. The wetwell and pad is then placed on compacted sub-base per engineer's specifications. Consult the Engineer of record for back fill requirements in areas of unstable soils. BACKFILLING-WET WELL- BACKFILL MATERIAL SHOULD BE PLACED IN 12" LIFTS AND COMPACTED TO A MINIMUM OF SOIL MODULUS OF 700 PSI. SELECTION, PLACEMENT & COMPACTION OF BACKFILL MATERIAL IS CRITICAL TO CORRECT INSTALLATION. SOILS THAT ARE SUITABLE FOR PIPE BEDDING CAN BE UTILIZED. COMPACTION SHOULD BE TIGHT ENOUGH TO PREVENT ANY MOVEMENT OF THE WETWELL. THE CONCRETE ANTI- FLOAT BALLAST SHOULD BE DRY ENOUGH TO SUPPORT THE BACKFILLING AND COMPACTION PROCESS. BRACING & FORMS SHOULD BE REMOVED. BACKFILL-VALVE BOX- MUST HAVE STABILIZED BEDDING, EQUAL TO THE COMPACTION FOR THE WETWELL. THE AREA BETWEEN THE VALVE BOX AND WETWELL SHALL BE HAND TAMPED. F/WrSCV/LF/Wetwell 48-60-72 Pg 2 of 2,Rev 2005