The total estimated project costs and funding sources are summarized in the table below. Description Total Project Expenditures 20

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8 The total estimated project costs and funding sources are summarized in the table below. Description Total Project Expenditures Environmental Site Assessment, Remediation Planning 142, , Remediation Actions and Monitoring (estimate) 432, , ,771 Estimated Total Expenditures 575, , ,150 Funding Sources Insurance Proceeds from WCIA (estimate) 345, , ,090 DOE's Voluntary Compliance Program (estimate) - 200, ,000 General Fund - estimated net cost to City 230,060 (88,000) 142,060 Estimated Total Funding Sources 575, , ,150 Shortly after the City learned that the fuel release had not been adequately addressed, Golder Associates was hired to conduct an environmental site characterization from late 2004 through early 2005 to delineate the nature and extent of the impacted groundwater. Golder did the initial investigation into the problem back in The remedial investigation found a gasoline groundwater plume extending north from the former underground tank site (Exhibit 2), under the former Honeywell building, and turning to the northeast toward City Hall. Cleanup of the affected groundwater is required under the State Model Toxics Control Act (MTCA). Golder was asked to develop a conceptual remedial approach for cleanup of the groundwater plume. After the conceptual approach was presented to John Bails of the Washington State Department of Ecology (DOE) and verbally approved, work began on a detailed plan for remediation. Following DOE acceptance, the remedial action plan was formalized, and engineering design and compliance monitoring plans were completed in the summer of The remedial action consisted of four components: Highly impacted groundwater was removed from the area north of the stream separating the Maintenance and Honeywell properties via excavation and the installation of an 80-foot-long by 10- foot-deep interceptor trench. The trench extracts impacted groundwater and pumps it to an activated carbon-based treatment system on the Maintenance property. After treatment, the water discharges to a King County/METRO sanitary sewer under discharge authorization number Approximately 260 cubic yards of highly contaminated soil were excavated from the south side of the Honeywell building. Biodegradation of the volatile organic compounds (VOCs) associated with the groundwater contamination plume has been enhanced by the introduction of ambient air via four buried airlines that intersect the gasoline plume and the application of oxidative chemicals. An existing network of monitoring wells to track the progress of the remediation was expanded. Short-term and long-term groundwater, surface water, and indoor air monitoring activities have been instituted. The remedial action was implemented in early 2007, and three subsequent quarterly groundwater monitoring events have been conducted. In general, concentrations of gasoline and its VOC constituents remain above MTCA cleanup levels but appear to be decreasing with time. However, groundwater monitoring has not been conducted for a length of time sufficient to consider the effects of seasonal variations in the groundwater table. Air monitoring is conducted semi-annually inside the former Honeywell building. Results from three air sampling events demonstrate that concentrations of VOCs inside the building are comparable to ambient air outdoors. Page 2

9 While the remedial action has been in place for less than a year, the results are generally encouraging. Additional monitoring data will be required before a meaningful evaluation can be conducted. A better assessment of when the City may be successful in receiving formal notification from DOE that no further action is necessary should be possible after another full year of monitoring. In a clean-up of this type, it is likely that another three years of groundwater treatment will be necessary, followed by two years of additional monitoring to demonstrate that the clean-up is complete. To complete the remediation work required through 2008, an additional appropriation of $175,150 is needed, funded by $120,150 from the 2007 General Fund year-end surplus and by $55,000 in WCIA insurance recovery proceeds. Description Amount Budget Approved March ,000 Estimated Total Expenditures - through ,150 Budget Appropriation Needed 175,150 Funding Sources Additional Insurance Proceeds from WCIA (estimate) 55,000 General Fund - Year End Transfer (Insurance Proceeds received in 2007) 120,150 This agenda bill requests the funding necessary for another round of chemical injection later this winter, the completion of the Remedial Action Report, the completion of the Quality Assurance Report, the completion of the Treatment System Operation and Maintenance Manual, and continued monitoring. RECOMMENDATION Maintenance Director MOVE TO: Appropriate $175,150 in the Equipment Rental Fund, funded by $120,150 from the 2007 General Fund year-end surplus and $55,000 from WCIA insurance recovery proceeds, and authorize staff to continue soil remediation work at the Honeywell site through Page 3

10 AB 4270 Exhibit 1 Page 5

11 AB 4270 Exhibit 1 Page 6

12 AB 4270 Exhibit 2 Page 7