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investigation or clean up. In fact, the site is proposed for closure despite elevated residual contamination in shallow soil, with the understanding that current/future land use is an operating gas station. According to the RWQCB, it is likely that the notice for public comment will be issued by the third quarter of 2018, followed by case closure, pending public review/comments. It is KMEA's understanding the City may wish to acquire this property or a portion thereof forthe purposes of redevelopment or street improvements. It is based on this understanding that the following scope of work is recommended following a likely and viable scenario as detailed below. The City may elect to allow the closure process to take its course to avoid the risks and liabilities and financial burden it would face otherwise if it elected to acquire the property before case closure. Under this scenario, the current consultant for the Responsible Party (PR) working with the RWQCB will carry out the tasks associated with the closure process at no risk or financial burden to the City. These tasks include, but are not limited to, the administrative filing of technical data associated with the Low Threat Closure Policy with the RWQCB; decommissioning of existing monitoring wells at the facility following receipt of approval form the regulatory agency; and site restoration activities. Following successful site closure, KMEA would provide on -site monitoring and sampling for the City during redevelopment and street improvement projects undertaken in the areas where residual petroleum hydrocarbon contamination in soil is present or suspected. The scope of work under this scenario would include a Phase I ESA to provide an update to the City as to the environmental site conditions prior to site redevelopment/improvements followed by Phase 11 ESA services consisting of as -needed monitoring during construction. Scope of Phase I and/or II ESAs (0: • Phase I ESA: The scope for Phase I ESA services would follow the approach as outlined in Section D of our proposal. • Phase II ESA: The scope for these services would also follow the approach as outline in Section D with the following additional assumptions and details. Based on its review of available information on the State Geotracker database, KMEA could find the following specifics regarding the residual petroleum hydrocarbon contamination which will remain in near -surface soils at this location following case closure: • Petroleum Constituents in Soil: >5 Feet bgs and s10 Feet bgs • Soil Concentrations of Benzene: > 8.2 mg/kg and < 12 mg/kg • Soil Concentrations of Naphthalene: > 9.7 mg/kg and < 45 mg/kg • Soil Concentrations of PAH: > 0,063 mg/kg and < 0.68 mg/kg • Area of Impacted Soil: Area of Impacted Soil > 82 by 82 Feet Source: State Geotracker Database -https://geotracker,waterboards,ca.gov/profile report?,global id=T0605900621&cmd=ptcpreport&Itcp id=104220 Assuming the zone of near -surface impacted soil with residual petroleum hydrocarbon contamination may fall within the footprint of the City's proposed street improvements, KMEA will: • Prepare a detailed work plan and site safety and health plan to include pertinent maps showing the aerial extent and boundary of the zone of impacted soil at the gas station based on date gathered during previous investigations by others. The impacted area will then be clearly marked on the ground and delineated by superimposing over the design drawings prepared by the City for the proposed improvements and construction footprint. • Conduct a geophysical survey of the proposed construction area to clearly and visibly mark the underground utilities in the area followed by establishing a DigAlert ticket number for local utilities to check for the presence and marking of their utilities network. • Coordinate the excavation work and schedule with the gas station owner/operator (assuming still in operation). • Prepare and establish a traffic control plan. City of Santa Ana Page 19 June 5, 2018 Various Environmental Services RFP NO.: 18-043