Regulatory Approval/No Further Action

1. Commercial Strip Mall, Los Angeles, California: Commercial strip mall with soils impacted by PCE/TCE and petroleum hydrocarbons.  Multi-depth soil gas sampling was used to demonstrate that residual contaminants did not pose a threat to human health or the environment, including to groundwater quality. 
   Agency: Los Angeles Fire Department and LA RWQCB.

2. Industrial Park, San Diego, California: Groundwater beneath property impacted by TCE.  Multi-depth soil gas sampling and groundwater monitoring were used to show that residual contaminants did not pose a threat to human health or the environment.  Moreover, contaminant fate and transport modeling was used to demonstrate that the contamination originated from hitherto unidentified upgradient sources.
   Agency: San Diego RWQCB.

3. Industrial Facility, Orange County, California:  Performed a risk-based evaluation of soil and groundwater impacts from TCE and its daughter products in soil and groundwater.  Delineated source area and developed approach to remediation of the site.
   Agency: Santa Ana RWQCB-98.

4. Industrial Facility, Silicon Valley, California:  Groundwater impacted by TCE and daughter products.  Demonstrated presence of more than one plume, including one originating from offsite sources.  Remediation of the contaminant plume resulted in site closure.
   Agency: San Francisco Bay Area RWQCB.

5. Commercial Property, Central Coast, California: Underground Storage Tank (UST) leak resulted in soil and groundwater impacted by gasoline and diesel fuel hydrocarbons.  Demonstrated that remaining contaminants did not pose a threat to human health or the environment.
   Agency: Ventura County Resource Management Agency and LA RWQCB.

6. Commercial Property, Silicon Valley, California:  Underground Storage Tank (UST) release of fuel hydrocarbons.  Soil gas and groundwater sampling used to demonstrate that remaining contamination did not pose a risk to human health or the environment, including to groundwater quality. 
   Agency: Santa Clara Valley Water District and San Francisco Bay Area RWQCB.

7. Industrial Facility, Bay Area, California: Hydrocarbon free product and arsenic in soils.  Demonstrated that based on soil sampling and chemical fingerprinting results, the residual contamination, including free product, did not pose a threat to human health or the environment.
   Agency: San Francisco Bay Area RWQCB.

8. Industrial Facility, San Gabriel Valley Superfund Site, S. California: Used chemical fingerprinting and GIS to demonstrate that remaining contamination in groundwater was from upgradient sources and that onsite treatment system had removed 1,1,1-TCA, 1,1-DCE and other solvents effectively from the subsurface.
   Agency: Los Angeles RWQCB.

9. Industrial Facility, Los Angeles, California: Performed a risk-based evaluation of soil and groundwater impacted by PCE, TCE, gasoline free product, including MTBE.  Demonstrate through fingerprinting that there were at least two distinct and separate “hot spots”.  Used Stiff plots and Piper diagrams to identify location of seepage of MTBE/BTEX into the Harbor.  Contaminant fate and transport modeling confirmed analysis.  Discrete hot spots identified for remediation.
   Agency: Los Angeles RWQCB.

10. School Property, N. California: Performed a risk-based evaluation of soils potentially impacted by metals, pesticides and PCBs.  Demonstrated that risks to students and staff were below levels of regulatory concern.
    Agency: Department of Toxic Substances Control.

11. High School, N. California:  Performed sampling and risk-based evaluation of lead in soils for a high school built on a former skeet shooting range.  Demonstrated that residual lead levels did not pose a threat to human health.
    Agency: Department of Toxic Substances Control.

12. Residential Development, N. California:  Investigated metals and fuel hydrocarbon contamination of soils on a 25-acre parcel slated for residential development. Performed risk-based evaluation to demonstrate that risks were below regulatory thresholds.
    Agency: Department of Toxic Substances Control.

13. Industrial Facility, N. California:  Risk-based evaluation of soils and groundwater impacted by gasoline.  Contaminant fate and transport modeling was used to demonstrate no impacts above regulatory thresholds would occur to ecological receptors in nearby river.  Agency: San Francisco Bay Area RWQCB.

14. Class 1 Landfill, S. California: Performed a risk-based evaluation of this 47-acre site containing a Class I landfill.  Multi-depth soil gas and groundwater sampling demonstrated impacts with TCE, Methylene chloride, Vinyl chloride in groundwater.  Contaminant fate and transport modeling was used to demonstrate containment of groundwater plume within site boundary.  Risk-based evaluation showed no elevated risks to human health or the environment.
    Agency: San Diego RWQCB and Department of Toxic Substances Control.

15. Underground Storage Tank Site, Los Angeles, California:  Risk-based evaluation of leaking gasoline UST with impacts to soil and groundwater.
    Agency: Los Angeles RWQCB.

16. Reclassification of Lead/Copper-impacted Soils, Bay Area, California:  Performed a risk-based evaluation of 5,000 tons of soils previously classified as hazardous waste. Successfully negotiated re-classification of these soils containing, lead and copper, as non-hazardous.
    Agency: Department of Toxic Substances Control.

17. Strip Mall, S. California: Performed multi-depth soil gas sampling for TCE, PCE Benzene and other VOCs. Using a risk-based evaluation, demonstrated that residual contamination did not present a risk to human health or the environment, including groundwater quality, above regulatory thresholds.  
    Agency: Los Angeles Fire Department.

18. Industrial Sites, Bay Area, California: Performed risk-based evaluations of soils and groundwater impacted by metals, chlorinated solvents, fuel hydrocarbons, paint thinners, and PCBs on two adjoining .industrial facilities. Performed risk-based evaluation which demonstrated no risks above regulatory thresholds to human health or marine organisms.  Agency: Alameda County Health Care Services and San Francisco Bay Area RWQCB.

19. Proposed High School Property Acquisition, N. California:  Performed risk-based site characterization and evaluation of for pesticides and metals in soils and groundwater.  Agency: Department of Toxic Substances Control.

20. School Property, N. California: Performed risk-based evaluation of lead-impacted soils to allow soils to be used as road base and as fill for parking lot.
    Agency: Department of Toxic Substances Control.

21. School Property, N. California:  Performed risk-based remedial investigation of leaking UST and fuel hydrocarbons discovered on school property during construction.
    Agency: Central Valley RWQCB and Department of Toxic Substances Control.

22. Dry Cleaners, Central Valley, California:  Remedial investigation of PCE in soil and groundwater. Performed multi-depth soil gas and grab groundwater sampling.  Demonstrated through chemical fingerprinting that PCE in groundwater was from an offsite source.  Agency: Central Valley RWQCB.

23. Burn Dump Site, N. California: Performed risk-based evaluation of VOCs, SVOCs, dioxins, and metals in soil and groundwater.  Identified risks for parcels based on current and proposed future land uses.
    Agency: Department of Toxic Substances Control.

24. Commercial/Industrial Property, Bay Area, California: Conducted a remedial investigation on this property adjoining a Superfund site and the Bay.  Demonstrated that elevated lead and polynuclear aromatic hydrocarbons (PAHs) and phthalates originated from the adjoining Superfund site and not from our client’s property.
    Agency: San Francisco Bay Area RWQCB.

25. Commercial Property, Silicon Valley, California:  Performed multi-depth soil gas to identify the source of PCE, TCE and their daughter products in groundwater.  Sampling results showed that these chlorinated solvents were confined to a small discrete “hot spot”.  The report recommended excavation of the hot spot, which was subsequently undertaken. Agency: San Francisco Bay Area RWQCB.

26. Paint Outlet Facility, Silicon Valley, California:  Performed a risk-based evaluation of impacts to soil and groundwater from paint thinners and non-fuel hydrocarbons.  Site had on-going remediation.  Demonstrated that the residual contamination posed no risks above regulatory thresholds to human health or the environment.
    Agency: Santa Clara Valley Water District.

27. Industrial Facility, Silicon Valley, California:  Performed a remedial investigation using soil gas and groundwater sampling.  Demonstrated source of TCE, DCE and Vinyl chloride in onsite soils. Used chemical fingerprinting to identify component of groundwater impacts from offsite sources.  Developed a workplan to remediate onsite soil and groundwater contamination.
    Agency: San Francisco Bay Area RWQCB.

28. School Bus Depot, N. California: Performed remedial investigation using soil sampling for metals and multi-depth soil gas sampling for gasoline and MTBE.  Contamination identified was well below levels of regulatory concern.
    Agency: Central Valley RWQCB.

29. Central Valley, California:  Performed a remedial investigation of soil gas and groundwater impacts from number of different dry cleaners.  Differentiated between sources of PCE and identified non-dry cleaner contributors to groundwater.
    Agency: Central Valley RWQCB.

30. Dry Cleaner, N. California: Conducted a multi-depth soil gas investigation.  Demonstrated that PCE in subsurface was from an offsite source.
    Agency: Central Valley RWQCB.

31. Industrial Facility, Silicon Valley, California: Performed a risk-based evaluation of arsenic, lead and mercury in site soils. Demonstrated that residual metals in onsite soils were lower than naturally occurring background concentrations of these same metals. Furthermore, demonstrated that anodizing operations were not a source of release of metals to the soil. 
    Agency: Department of Toxic Substances Control.

32. UST Facility, S. California: Performed a risk-based evaluation of soil, soil gas and groundwater impacts from gasoline. Demonstrated that residual impacts did not present risks to human health or the environment above regulatory threshold.
    Agency: Los Angeles RWQCB.

33. UST Facility, Michigan: Performed a risk-based evaluation of soil and groundwater impacts from gasoline. Demonstrated that remediation efforts had cleaned up most of the subsurface and that residual impacts did not present risks to human health or the environment above regulatory thresholds.
    Agency: Michigan Department of Natural Resources.

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