R L Alia Company 12/7/2020 - Laserfiche WebLink

CITY OF EVERETT SPECIAL PROVISIONS 1. All lids, grates, and hatches larger than 24 inches in a dimension shall be hinged and shall be constructed in a manner which allows a single individual to open them without special equipment. 2. All lids, grates, and hatches shall be equipped with a pick-hole or handles. Stormwater Biofiltration System The structure shall be pre-cast structural concrete with a minimum 28-day compressive strength of 5,000 psi, reinforcing per ASTM A615, Grade 60, and supports pedestrian loading as indicated by AASHTO. Each chamber shall have access hatches for maintenance in accordance with WISHA standards and sized to allow removal of all internal components without disassembly. Structure knockouts shall be provided to accept pipes of the size, material, and elevation shown in the plans. Pretreatment chambers shall use replaceable cartridges that contain non-proprietary filter media. Treatment chambers shall be a closed vault where specified on the plans. Treatment chambers shall use media that does not require replacement over the life of the facility and meets the requirements of ASTM C330, ASTM C331, and AASHTO M195. Aggregates must have a minimum 24-hour water absorption of 10.5 percent mass. Media shall not contain any organic material. Treatment media thickness shall be at least 19 inches from inlet to outlet. Media should be contained within a structure to provide at least 2"of space from vertically extending walls of the concrete structure. Plants, where indicted in the plans, shall comply with the following: 1. Plants shall be <to be determined and confirmed by manufacturer> 2. Plants shall be minimum 6-inch pots and shall be healthy and sturdy specimens acceptable to the Engineer. Access covers shall be designed in accordance with Section 4-4.2 (3) of the Design and Construction Standards and Specifications and the following: 1. All lids, grates, and hatches larger than 24 inches in an dimension shall be hinged and shall be constructed in a manner which allows a single individual to open them without special equipment. 2. All lids, grates, and hatches shall be equipped with a pick-hole or handles. 7-06.1(4) Construction Requirements Vortex Pretreatment Device and Stormwater Biofiltration System The contractor shall exercise care in the storage and handling of the water quality treatment structure components prior to and during installation. Any repair or replacement costs associated with events occurring after delivery is accepted and unloading has - commenced shall be borne by the contractor. All components shall be subject to inspection by the City. All components are subject to being rejected or identified for repair if the quality of materials and manufacturing do not comply with the requirements of the plans and special provisions. Components which have been identified as defective may be subject for repair where final acceptance of the component is contingent on the discretion of the Engineer. The water quality treatment structure shall be installed in accordance with the manufacturer's recommendations and related sections of the contract documents. The manufacturer shall provide the contractor installation instructions and offer on- site guidance during the important stages of the installation as identified by the manufacturer at no additional expense. A minimum of three (3) business days' notice shall be provided to the manufacturer prior to their performance of the services included under this subsection. Jackson Park Area Stormwater Separation September 2020 WO No. - UP3703 Division 7—STORM, SEWER, WATER SP-160