SSLM Properties LLC 9/13/2017 Amendment 7

Memorandum to Michael Palacios,City of Everett December 2, 2016 Page 2 remedial excavation areas for the purpose of this ROM cleanup cost estimate,as follows:250 feet by 125 feet and 100 feet by 90 feet in plan dimensions, both extending to an average depth of 4 feet bgs.The larger remedial excavation corresponds to the sawmill operations and log storage areas in the south-central portion of the north part of the Site (north of the I-5 overpass). The smaller remedial excavation corresponds to the maintenance and fuel storage area in the east-central portion of the north part of the Site. The total quantity for these excavation areas is approximately 6,000 in-place cubic yards,equating to an estimated 9,000 tons of contaminated soil, assuming a soil unit weight of 1.5 tons per cubic yard. Excavation sidewalls are assumed to be vertical and soil excavation not assumed to extend off site. No costs for dewatering or excavation shoring are included. Cleanup confirmation soil samples would be obtained from the base and sidewalls of the remedial excavations to document the successful removal of contaminated soil greater than MTCA cleanup levels.After removal of contaminated soil,the excavation would be backfilled with clean imported soil. ® A 2,500 square foot asphalt cap is assumed for locations where residual contaminant concentrations may remain following excavation. The use of capping as a component of the cleanup action typically requires an environmental covenant as a condition of Ecology NFA determination. ® The geophysical survey completed as part of the Phase II ESA identified a subsurface anomaly at one location in the survey area and the site history suggests there may be a fuel storage underground storage tank (UST) on the property. Therefore, remedial costs include removing one UST in accordance with applicable regulations. el The findings, opinions, and cost estimates presented in this memo are based on currently available information. As additional information becomes available, our findings,opinions and cost estimates may change.Actual costs will vary and could exceed the estimates presented depending on variables(currently not defined)such as the extent of contamination,the results of the RI and FS,regulatory changes,duration of remedial action,degree of institutional controls and future site use.Unit costs are based on experience, recent contractor quotations for projects with some similar aspects, and best professional judgment;we did not obtain quotes from local contractors. The ROM cleanup cost estimate is as follows(see attached Table for cost breakdown): DESCRIPTION ESTIMATED ROM COST RI,FS and CAP $98,000 Remedial Excavation and Capping $925,000 Grounwater Cleanup Confirmation $84,000 and Regulatory Closure Total $1,107,000 25%Contingency $279,850 Total with Contingency $1,386,850 We have prepared this memorandum for the exclusive use of the City of Everett.Within the limitations of scope, schedule and budget,our services have been executed in accordance with generally accepted environmental science practices in this area at the time this report was prepared.No warranty or other conditions,express or implied,should be understood.