Selected Projects
Project Manager/Director Of Environmental Compliance Projects
We have served as the project manager or project director for numerous environmental compliance projects. Here are some examples:
Human Health Risk Assessment at a former oil refinery facility in Miri, Sarawak, Malaysia. The primary objective was to evaluate the potential health risks and hazards posed by petroleum hydrocarbons and lead that were detected in shallow soils, groundwater, and surface water at and around the site. Results of the Risk Assessment indicated that, in the absence of soil remediation, some site-related chemicals may be present at concentrations that could pose a health risk to hypothetical future onsite receptors, including construction workers, adult and child residents, and future onsite workers. In anticipation of site remediation activities, Risk- Based Target Levels (RBTL) were developed for the site. The RBTL’s proved acceptable to the local environmental regulatory agency and were successfully implemented.
Work plans for site characterization, human and ecological risk assessments, and site remediation of Peru’s La Oroya Metallurgical Complex. Work was conducted at the request of Peru’s Empresa Minera del Centro del Peru, S.A. – Centromin. Centromin sought to define: (1) the area currently impacted by emissions released to the air by the La Oroya Metallurgical Complex (LOMC); (2) current levels of soil contamination that can be attributed to LOMC emissions; (3) potential threats to human and ecological receptors posed by emissions residuals that can still be found in the affected area; and (4) remedial alternatives that could be implemented to mitigate or reduce potential health risks and hazards. Peru’s Ministerio de Energia y Minas reviewed and approved the work plans.
Human Health and Ecological Risk Assessment at an active military research facility located in central California. Environmental investigations conducted at the facility detected several chemicals, including perchlorate, metals, nitrate, nitrite, energetics, and trace levels of semi-volatile organic compounds in soil and shallow groundwater within discrete areas of the site. The objectives of the Risk Assessment were to: (1) estimate the potential future risk to human health; (2) estimate the potential threat posed by site-related chemicals to ecological receptors; and (3) develop site-specific, risk-based concentrations for the protection of human health and ecological receptors.
Exposure pathways evaluated in this Risk Assessment for human receptors included: (1) accidental ingestion of soil, (2) dermal contact with soil and dust, (3) inhalation of soil particles suspended in air, and (4) consumption of homegrown fruits and vegetables. Soil cleanup levels for protection of groundwater resources were also developed.
Human Health and Ecological Assessment for the former BKK Landfill in the City of Carson, California. The former landfill was used to dispose of industrial chemicals, petroleum production wastes, and domestic rubbish. The Victoria Golf Course and other recreational, industrial, and commercial facilities currently occupy the site. The risk assessment included the evaluation of potential health risks to offsite residents, onsite adult and child recreational receptors, onsite golf course workers, and construction workers. The ecological portion of the evaluation included a qualitative and quantitative appraisal of the potential effects the site might have on plants and animals other than people and domesticated species.
Results of the Human Health and Ecological Risk Assessment were used to evaluate the potential for the former BKK Landfill to pose an unacceptable risk or hazard to human and ecological receptors. The California Department of Toxic Substances Control reviewed and approved the Human and Ecological Risk Assessment report
Human Health Risk Assessment for the Runkle Ranch property in Simi Valley, California. The Runkle Ranch property is located adjacent to the Santa Susana Field Laboratory (SSFL), a former nuclear reactor and rocket-testing facility. The Runkle Ranch property was found to be contaminated with chemical and radioactive substances from the SSFL site. A home developer interested in developing the Runkle Ranch property for residential use commissioned the Risk Assessment study. The objective was to determine whether the presence of chemical and radiological contaminants in soil represented a health risk to future occupants of the site. Results of the risk assessment showed that the property could be safely developed for residential use. The Simi Valley City Council approved a project to build 461 homes on the 1,595-acre property.
Human Health and Environmental Risk Assessment at a vacant 500+ acre property in Nevada surrounded by an industrial park, a former landfill, wastewater treatment ponds, and a residential development. Plans for development of the property included the construction of a retirement community and a golf course. Site assessments had identified the presence of radionuclides and trace amounts of industrial solvents and chlorinated hydrocarbons in soil and groundwater. The objective of the risk assessment was to evaluate whether the presence of such chemicals in soil and groundwater represented a health risk to future occupants of the site. Results of the risk assessment showed that the property could be safely developed for residential use, and that there was no need to remove anthropogenic chemicals found in soil and groundwater.
Human Health and Ecological Risk Assessment at a former military facility located in the San Francisco Bay area. The major objectives of the Risk Assessment were to (1) estimate the magnitude of potential human health risks associated with the most likely future land use conditions; (2) identify environmental media and contaminants that pose a significant threat to human and ecological receptors; (3) identify environmental contaminants that pose little or no risk to humans and ecological receptors; and, (4) provide the basis to support risk management decisions about the need for further action at the site.
The human health portion of the Risk Assessment estimated potential health risks under “total,” “incremental,” and “ambient” risk scenarios. These scenarios were developed specifically for the military facility in consultation with federal and state health and environmental protection regulatory agencies. “Total” risk represents the risks from potential exposure to all detected analytes (inorganic and organic) present at the site at concentrations above ambient concentrations. “Incremental” risk represents risks from potential exposures to the subset of chemicals detected at concentrations above ambient concentrations and with maximum chemical concentrations above conservative residential risk-based screening concentrations. “Ambient” risk represents the risk from exposure to inorganic chemicals that are within the background soil concentration range defined for the site. The Risk Assessment report was reviewed and well received by the U.S. Navy, the U.S. Environmental Protection Agency and the California Department of Toxic Substances Control.
Human and Ecological Screening Risk Evaluations for existing and proposed school sites in Southern California. The risk assessments were conducted in accordance with the California Department of Toxic Substances Control’s (DTSC) Preliminary Endangerment Assessment guidance. Sites evaluated contained various potential contaminants including agricultural pesticides, dioxins/furans, hydrogen sulfide, heavy metals, petroleum hydrocarbons and chlorinated hydrocarbons. Several risk evaluations were instrumental to obtain “No Further Action” recommendations from the DTSC.
Health Risk Assessments for real estate properties found to contain pesticide residues. The objective of the risk assessments was to determine if pesticide residues in soil represented a threat to occupants of future developments planned for the properties. Examples of sites evaluated recently include an orange grove in Riverside, California; a military housing facility in Alameda, California; and a school campus in Northridge, California. The results of the risk assessments were used to determine regional, background pesticide concentrations; to define acceptable pesticide residue levels; to design cost-effective risk control measures; or to obtain “No Further Action” recommendations from state and local regulatory agencies.
Human Health Risk Assessment at a California Superfund Site in Huntington Beach, California. The former landfill was used to dispose of industrial chemicals, waste drilling mud, petroleum production wastes, and construction/demolition debris. The risk assessment included the evaluation of potential health risks to offsite residents, onsite workers, trespassers and ecological receptors. The risk assessment was also used to set risk-based cleanup levels for chemicals identified at the site. In addition, risk assessment techniques were used to design a waste recycling plan for some of the waste materials found at the site. Risk-based cleanup levels and remedial alternatives were reviewed and approved by the California Department of Toxic Substances Control (DTSC).
Toxicological Evaluation of perchlorate in soil and produce. The need for a toxicological evaluation arose when a farming company in Redlands, San Bernardino County, California, was informed that the water they were using for irrigation was contaminated with perchlorate. The source of perchlorate was traced back to an industrial facility 6 miles upgradient from the farm. A subsequent site assessment revealed the presence of trace quantities of perchlorate in soil and vegetable edible material. As part of the evaluation, a pilot study was conducted to determine the perchlorate degradation rate in soil.
Results of the toxicological evaluation indicated that the concentrations of perchlorate in soil and produce were too low to represent a health risk to persons exposed to soil at the site or to consumers of vegetables grown at the farm. Results of the pilot degradation study indicated that perchlorate degrades rapidly in soil in the presence of adequate amounts of organic matter and soil moisture. The toxicological evaluation of perchlorate was published as a book chapter (see H. Robles, 2000a).
Risk Assessment of a California Superfund Site in Santa Fe Springs, California. The site was formerly used to dispose of oil well drilling mud and drilling wastes, and was contaminated with asbestos, lead, barium, PCBs, polynuclear aromatics, and petroleum hydrocarbons. The risk assessment considered evaluation of potential exposure of future on- and off-site residents, including children in a neighboring day care center. Results of the risk assessment were used to demonstrate that site activities did not contribute to existing groundwater contamination, negotiate soil cleanup goals, and select cost-effective and safe remedial alternatives.
Health Risk Assessment of a RCRA-permitted facility in Southern California. Conducted an Environmental and Human Health Risk Assessment for an active hazardous waste storage facility to determine if the addition of new waste streams to the facility would represent a potential health threat to the surrounding community. Results of the risk assessment showed that the hazardous waste contractor had adequate facilities and the addition of new waste steams would not represent a health hazard. The risk assessment was used in support of an application for RCRA permit expansion.
Proposition 65 projects for evaluating current or potential exposures to chemicals regarded by the State of California to be carcinogenic or reproductive toxicants. Activities included interpretation of Proposition 65 No Significant Risk Levels (NSRL), evaluation of lender or developer liability from contaminated wastes at a property, assessment of current facility emissions to assess "duty to warn" and other reporting requirements and litigation support.
Evaluation of Heath Hazards associated with the presence of methane and hydrogen sulfide in subsurface soil within a residential and commercial area of Newport Beach, California. Evaluated the potential health and environmental risks associated with methane and hydrogen sulfide gases under the area proposed for the Balboa Project in the City of Newport Beach, California. The assessment included the evaluation of potential health risks to construction workers as well as to occupants of the site and its visitors. Results of the risk assessment were used to design and select risk control measures.
Human Health and Environmental Risk Assessments at former gasoline service stations in Arizona. Conducted risk assessments following the Arizona Department of Health Services’ (ADHS) and Arizona Department of Environmental Quality’s (ADEQ) Risk Assessment Guidelines for Underground Storage Tank Sites. Risk assessments developed for the sites were used to request no further action from regulatory agencies. During development of the risk assessments, several conversations were held with Dr. Phil Amadi of the ADEQ regarding the danger of compounding conservatism in risk assessment. Based on these discussions, Dr. Amadi invited Dr. Robles to give a presentation to ADEQ staff on the appropriate use of fate and transport modeling in risk assessments.
Lecturer and Litigation Support Roles
We have extensive experience training others and providing clients with litigation support services. Here are some examples:
Lecturer for an intensive 32-hour training course in Environmental and Human Health Risk Assessment for technical personnel at the Chilean Ministry of the Environment (Ministerio del Medio Ambiente, Gobierno de Chile). The objective of the training seminar was to provide Ministry personnel with the tools necessary to conduct and review Health Risk Assessments for contaminated sites.
Expert Witness in the Golden Triangle Construction, Inc. v. Dynamic Sports Construction, Inc. case (District Court, Adams County, Colorado, Case No. 2009 CV 1425, Division A). Case involved alleged mercury vapor exposure associated with renovation of rubberized gym floor. Conducted mercury vapor exposure assessment and dose exposure reconstruction studies. Also conducted technical analysis of Industrial Hygiene reports and records, health risk assessment, and preparation of an exposure assessment report. The exposure assessment provided the basis of testimony in the areas of toxicology and occupational health.
Other Toxicology Roles
Toxicology Consultant for the International Silva Reservoir Panel, Commission for Environmental Cooperation (CEC), Montreal, Quebec, Canada. The CEC was created by the North American Free Trade Agreement (NAFTA) to resolve environmental issues between countries participating in NAFTA. The panel of selected scientists from Canada, Mexico, and the United States was convened by the CEC to provide scientific and technical assessment related to the deaths of 40,000 waterfowl at a reservoir in Mexico.
Staff Toxicologist for the Center for Rehabilitation and Occupational Health, Saint Francis Memorial Hospital, San Francisco, California. Evaluated patients suspected of occupational injury from chemical exposure, wrote toxicological evaluations of suspected etiological agents, and provided litigation support.
Toxicology Study Director conducting studies to assess the pharmacological and toxicological properties of chemicals and pharmaceuticals. The studies were conducted under Good Laboratory Practice (GLP) regulations to support applications for U.S. EPA and FDA registration of the tested compounds.