Appendix I - Hazardous Materials Documentation - VTA

Contaminant Management Plan, SVRT/BART Extension
hydrocarbons within the motor oil range (TPH-MO). Additionally, a large stockpile of soil was identified as
containing relatively high levels of chromium.
The lead and petroleum hydrocarbon results from these investigations can be summarized as follows:
• The shallow soil beneath the ballast (0 to 3 feet bgs) contains sufficient total and extractable lead to
require the material be handled as a California Regulated Waste if disposal is considered.
• One shallow soil sample contained a lead level high enough for the soil to be classified as a Resource
Conservation and Recovery Act (RCRA) hazardous waste.
• Data on deeper soil samples (3 to greater than 20 feet bgs) indicates that lead concentrations are not
sufficient to require classification of the soil as a RCRA hazardous waste or California (non-RCRA)
hazardous waste.
• TPH-MO was found in approximately half of the shallow (up to a depth of 2 feet) soil samples at
concentrations exceeding 100 mg/kg, up to a level of 25,000 mg/kg.
• Significant concentrations of TPH-MO were not detected in soil samples collected from depths of 5
feet or greater.
2.4.2 Impacts to Groundwater
2.4.2.1 Line Segment
Investigations of groundwater quality have been focused where retained cuts, depressed crossroads, and deep
foundation footings are proposed and dewatering may be required. Depth to groundwater along the SVRT
alignment is approximately 15 to 20 feet bgs, which may locally occur under confined or semi-confined
conditions.
Based on the investigations described in Section 2.3.1, groundwater removed during dewatering activities is
not expected to be contaminated with dissolved metals, although total metals levels (including metals in
suspended solids) may be significant in some locations. In some locations, the groundwater is expected to be
contaminated with organic chemicals from off-site sources. These locations include:
• Just north of Montague Expressway, where groundwater is impacted by a chlorinated solvent plume
commonly referred to as the Jones Chemical plume, and groundwater treatment system piping passes
under the UPRR tracks. This plume includes chlorinated solvents at concentrations generally below
200 micrograms per liter (µg/L);
• Just north of Montague Expressway, where groundwater on the adjacent Great Mall (formerly the
Ford Automobile Assembly Plant) property is impacted with residual petroleum hydrocarbons. Note
that the Jones Chemical Plume also extends onto this property; and
• The Kato Road underpass area, where groundwater is impacted by the Scott Creek Business Park
chlorinated solvent and diesel plume, where levels are generally below 100 µg/L.
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