Blue Mountain Construction Group, LLC 11/19/2024

CITY OF EVERETT SPECIAL PROVISIONS 3rd Ave Water Quality Facility Division 7 – STORM, SEWER, WATER September 12, 2024 WO No. – UP 3775 SP – 178 7-06.2(3) Roof Drain Connection The Roof Drain Connection shall be solid wall SDR35 PVC pipe and fittings needed to connect private roof drains to the storm system and Water Quality Treatment Facility as shown in the Plans. 7-06.3 Construction Requirements 7-06.3(1) Performance Requirements Pretreatment Unit Provide a manufacturer’s certificate of compliance in accordance with Section 1- 06.3 demonstrating that the proposed product complies with the following requirements: Washington State Department of Ecology approval requirements: general use level designation for pretreatment. The Pretreatment Unit shall has approved General Use Level Designation (GULD) for “Pretreatment” from the Washington Department of Ecology. The locations of the access lids shall be confirmed to provide 2-in minimum clearance to the sidewalk face of curb prior to ordering the unit from the manufacturer. The Pretreatment Unit shall be sized in accordance with the GULD approved design requirements for the minimum water quality flow rates shown in the Plans and specified herein. Exterior dimensions shall fit within the designed footprint of the facility. Treatment: The Pretreatment Unit shall be sized to treat the design flow rate designed in the Plans. Annual TSS removal efficiency models shall be based on documented removal efficiency performance from full scale laboratory tests based on a particle size gradation defined by the following: Percent of Sample Particle Size Range 27% >250 micron 11% 150-250 micron 7% 100-150 micron 9% 75-100 micron 4% 63-75 micron 42% <63 micron Annual TSS removal efficiency models shall only be considered valid if they are corroborated by independent third-party field testing. Said field testing shall include influent and effluent composite samples from a minimum of ten storms at one location.