1870 ROSS AVE SEPA 017 - 017 -DAGMAR'S BOAT LAUNCH DREDGE Land Use Decision Documents 2025-04-16

Conservation measures will be employed during dredging to avoid or minimize potential adverse impacts on the aquatic environment.The following conservation measures and best management practices will be implemented: • The sediment removal footprint is within the existing boat launch and therefore already disturbed. Sediment removal will not occur within the main Snohomish River channel • All in-water work will be limited to periods determined by state and federal agencies to avoid potential adverse effects on listed salmonids. • All equipment will be inspected daily to ensure that it is in proper working condition. • A silt curtain will be deployed at the end of the existing boat launch floats during all sediment removal periods to minimize turbidity within the main river channel. • The contractor will be responsible for the preparation and implementation of a Spill Prevention,Control,and Countermeasures(SPCC) Plan.The SPCC Plan will be submitted to the project engineer prior to the commencement of any construction activities.A copy of the plan with any updates will be maintained at the work site by the contractor. The contractor will also maintain at the job site the applicable equipment and materials designated in the SPCC Plan. • Excess or waste materials, petroleum products,chemicals,or other toxic or deleterious materials will not be allowed to enter waters of the state. 8b. Will your project impact a waterbody or the area around a waterbody? [helpl l Yes, minimal and temporary impacts to the Snohomish River El No 8c. Have you prepared a mitigation plan to compensate for the project's adverse impacts to non-wetland waterbodies? [helpi • If Yes,submit the plan with the JARPA package and answer 8d. • If No,or Not applicable,explain below why a mitigation plan should not be required. ❑ Yes Ii No ❑ Don't know Minimal amounts of shoaled sediments(875 CY)will be removed from an existing boat launch down to the existing mudline. No removal will occur outside of the existing boat launch within the main channel of the Snohomish River.The area is an active boat launch where propeller scour and other boating activities provides marginal intertidal habitat for fish. Upper intertidal habitat is composed of concrete launch ramp(Sheets 1 and 2). Upland areas are impervious,used for parking and vessel dry storage. Conservation measures and best management practices will be sufficient and protective of the river and aquatic resources present. No mitigation is needed. 8d. Summarize what the mitigation plan is meant to accomplish. Describe how a watershed approach was used to design the plan. • If you already completed 7g you do not need to restate your answer here. [help] ORIA-16-011 Page 8 of 15