Laserfiche WebLink
I <br /> Memorandum to Michael Palacios,City of Everett <br /> December 2,2016 <br /> Page 2 <br /> remedial excavation areas for the purpose of this ROM cleanup cost estimate,as follows:250 feet by 125 <br /> feet and 100 feet by 90 feet in plan dimensions, both extending to an average depth of 4 feet bgs.The <br /> larger remedial excavation corresponds to the sawmill operations and log storage areas in the south-central <br /> portion of the north part of the Site (north of the I-5 overpass). The smaller remedial excavation <br /> corresponds to the maintenance and fuel storage area in the east-central portion of the north part of the <br /> Site. The total quantity for these excavation areas is approximately 6,000 in-place cubic yards,equating to <br /> an estimated 9,000 tons of contaminated soil, assuming a soil unit weight of 1.5 tons per cubic yard. <br /> Excavation sidewalls are assumed to be vertical and soil excavation not assumed to extend off site. No <br /> costs for dewatering or excavation shoring are included. Cleanup confirmation soil samples would be <br /> obtained from the base and sidewalls of the remedial excavations to document the successful removal of <br /> contaminated soil greater than MTCA cleanup levels.After removal of contaminated soil,the excavation <br /> would be backfilled with clean imported soil. <br /> Is A 2,500 square foot asphalt cap is assumed for locations where residual contaminant concentrations may <br /> remain following excavation. The use of capping as a component of the cleanup action typically requires <br /> an environmental covenant as a condition of Ecology NFA determination. <br /> Er The geophysical survey completed as part of the Phase II EM identified a subsurface anomaly at one <br /> location in the survey area and the site history suggests there maybe a fuel storage underground storage <br /> tank (UST) on the property. Therefore, remedial costs include removing one UST in accordance with <br /> applicable regulations. <br /> The findings, opinions, and cost estimates presented in this memo are based on currently available <br /> information.As additional information becomes available,our findings,opinions and cost estimates may <br /> change.Actual costs will vary and could exceed the estimates presented depending on variables(currently <br /> not defined)such as the extent of contamination,the results of the RI and FS,regulatory changes,duration <br /> of remedial action,degree of institutional controls and future site use.Unit costs are based on experience, <br /> recent contractor quotations for projects with some similar aspects,and best professional judgment;we <br /> did not obtain quotes from local contractors. <br /> The ROM cleanup cost estimate is as follows(see attached Table for cost breakdown): <br /> DESCRIPTION ESTIMATED ROM COST <br /> Ri,ES and CAP - -. $98,000 <br /> Remedial Excavation and Capping $925,000 <br /> Grounwater Cleanup Confirmation $84,000 <br /> and Regulatory Closure <br /> Total $1,107,000 <br /> 25%Contingency • $279,850 <br /> Total with Contingency $1,386,850 <br /> We have prepared this memorandum for the exclusive use of the City of Everett.Within the limitations of scope, <br /> schedule and budget,our services have been executed in accordance with generally accepted environmental <br /> science practices in this area at the time this report was prepared.No warranty or other conditions,express or <br /> implied,should be understood. <br /> • <br /> 11 <br />