ERAS took over a contaminated gasoline station from a former environmental consultant. Work performed by ERAS included installation of groundwater monitoring, vapor extraction and groundwater extraction wells. Soil borings were drilled in off-site areas to assess the extent of groundwater contamination under the residential neighborhood. Work also included hazardous and non-hazardous waste disposal coordination, groundwater monitoring, and preparation of a feasibility study.

A risk assessment was also performed that indicated the groundwater plume was stable and decreasing in concentration. No indoor air issues were indicated by analysis of soil and groundwater samples. ERAS eventually conducted case closure activities and the case was closed by the San Mateo County Department of Environmental Health.
(Client: Mr. Parviz Darabi, Esq.)

ERAS performed a Phase 1 investigation for a small commercial office/warehouse building in San Mateo . Building department records indicated that a gasoline service station was located on the Property from 1929 to 1972. Station building plans on file indicated the first set of underground tanks and pump islands were removed and replaced with a new set of tanks and pumps in 1953 in different locations in the same general area. The current building was constructed partly over the former gasoline station improvements.

ERAS performed a Phase 2 soil and groundwater investigation under permit requirements and work scope approval of the San Mateo County Department of Environmental Health (SMCDEH). A total of 6 soil borings were drilled. Soil samples were collected for appropriate analysis under the former USTs, pump island and oil/water separator inside and outside the newer building where the former items could be accessed. Groundwater samples were collected in areas down-gradient of the former USTs and pump islands that were located under inaccessible areas of the current structure. The concentrations of petroleum hydrocarbons were low enough and the investigation comprehensive enough for the SMCDEH to not require additional investigation and the building was successfully financed.
(Client: Michael Barnette, Colliers Parrish)

ERAS performed a Phase I investigation for a commercial building in western Hayward. Review of the file for a closed fuel leak site adjacent to the east indicated that very high concentrations of gasoline contamination were found ON THE PROPERTY in 1996. The data collected by ERAS indicated an off-site source even though the most likely source site had been closed by the City of Hayward and Regional Water Board. This included 1) no gasoline found in soil and high concentrations of gasoline in groundwater and 2) no historical evidence of uses of the area of the Property that would have caused gasoline contamination.

The owner was unable to sell the Property and asked ERAS to suggest a Phase 2 investigation to prove the contamination was migrating from off-site. ERAS instead performed a Technical Review of the file for the leak case. ERAS was able to document that high concentrations of gasoline was left in soil beneath the groundwater table under the property line of the adjacent site. The contamination appeared to have been washed into an adjacent unlined creek, migrated downstream and then contaminated groundwater under the up-gradient corner of the Property. The Regional Water Board agreed and wrote a “comfort letter” for the owner and buyer and the Property was sold using SBA financing.
(Client: Paul Beckwith, Cornish and Carey)