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CRITERION REQUIREMENT <br /> Clearwell Access • Provide a minimum of four access hatches or structures for the clearwell:one personnel <br /> access hatch over a new stairway near the southwest corner of the East Clearwell,one <br /> personnel access hatch at the location of the existing west personnel access on the <br /> north end of the clearwell,one sampling hatch in the proximity of clearwell influent line, <br /> and one equipment access hatch located in the proximity of the northeast corner of the <br /> clearwell. If the equipment hatch can be located close enough to the clearwell influent <br /> line,then the sampling hatch may be located within the equipment hatch. Design <br /> access to allow for safe,easy,and efficient operations, maintenance,and inspection <br /> access by personnel.All access points shall be provided with railings meeting applicable <br /> regulations.Account for the need for personnel to carry tools and equipment for <br /> conducting maintenance activities in sizing access facilities. <br /> • Include all necessary safety features to meet codes, including but not limited to stairs, <br /> platforms,guard railing, "life-lines",fall protection systems,safety cables,and ladders. <br /> • All hatches and access points to clearwell interior shall be water tight,insect proof,and <br /> only require one person to open. Hatches shall provide smooth,one-hand operation and <br /> an automatic hold-open arm lock to ensure safe egress. Hatches shall include a positive <br /> latching mechanism for security. <br /> • Remove existing ladders, leaving a clean surface flush with the wall. Replace one ladder <br /> as noted below for personnel access. <br /> • Remove embedded anchor bolts and/or exposed reinforcing to a minimum of 3/4"below <br /> finished face of concrete and apply an epoxy concrete patch acceptable for use with <br /> potable water. <br /> • Hatch Locations: <br /> • Personnel access(Southwest):Shall be located on the southwest corner of the roof. <br /> Provide an exterior staircase for roof access.Provide guardrails along roof for safety <br /> as required by Code. Provide interior staircase to access the bottom of the East <br /> Clearwell with working platforms with adequate headroom while standing.Size <br /> access and platform(s)to allow personnel to comfortably conduct maintenance and <br /> inspection activities and allow for personnel to descend the existing interior stairs <br /> without ducking. Minimum hatch size of 3 feet by 6 feet. <br /> Personnel access(North):One shall be located on the north end, near the existing <br /> west inside ladder,located to allow access and sampling of the clearwell effluent. <br /> One shall be located on the north end near the existing east inside ladder. Provide <br /> guardrails along roof for safety.Size access to allow personnel to comfortably <br /> conduct maintenance and inspection activities. Minimum hatch size of 3 feet by 3 <br /> feet. <br /> Equipment access: Provide double-leaf hatch on the northeast corner of clearwell. <br /> Hatch shall be located sufficiently close to the edge of the clearwell to allow for easy <br /> crane access. Provide guardrails for safety as required by Code.Size access hatch to <br /> allow for lowering equipment, including a scissor lift,through the hatch into the East <br /> Clearwell with a crane. Provide,at a minimum,a 6-foot x 12-foot clear opening. <br /> Center Baffle • Salvage hanging baffle and reinstall with acceptable new roofing system. <br /> Curtain • RE-install the baffle to the full plan view extent,extending vertically from the floor to <br /> above the high water level for the clearwell. <br /> • Provide positive anchorage and sealing to the floor such that no short-circuiting of <br /> clearwell flows under the baffle is possible. <br /> City of Everett January 29,2020 <br /> Water Filtration Plant East Clearwell Roof Replacement DB Project Supplementary Conditions Page 7 <br />