1622 E MARINE VIEW DR WHOLE SITE 2022-02-01

Riverview Apartments Stormwater Pollution Prevention Plan Table 1 includes a list of suspected and/or known contaminants associated with the construction activity. 0 Table 1 — Summary of Site Pollutant Constituents Constituent (Pollutant) Location Depth Concentration None known None known None known None known 1.2 Proposed Construction Activities The project will provide 203 new residential units in a combination of 5 garden -style apartment and 4 carriage (living over garage) units. A stand-alone recreation building is planned near the central portion of the site. Private open space and recreation amenities — indoor and outdoor — will be included with the finished project. Surface parking, storm drainage facilities, and associated on -site utility infrastructure will be developed. In addition, the project will include a new driveway access on the western frontage of East Marine View Drive and will include new pedestrian ramps. The project will create a total of approximately 4.81 acres of impervious surface. • The developed site is required to provide Enhanced Water Quality treatment and flow control facilities per current COE surface water standards. All storm water runoff from the improved site will be collected and conveyed to a formal flow control and treatment facility prior to being released to the existing, downstream, public storm system. The project proposes a subsurface detention vault with a flow control riser to provide detention storage and flow control. This system is preceded by a bioretention facility sized to provide the required water quality treatment in accordance with the Enhanced Water Quality treatment standard. The detention vault and rain bioretention facilities have been designed per City of Everett standards. Contaminated Site Information: There are no known contaminated soils or groundwater location on -site. CPH Project No. 0024-17-037 August 29, 2018 CP I H CONSULTANTS Page 5