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Denise Clendening, PhD, REA II
Director, Site Assessment Services

Denise has nearly 27 years of experience providing technical oversight and performing human health risk assessments, site assessments, and investigations of chemical waste at Resource Conservation & Recovery Act and Superfund sites. She is adept at applying alternatives that are economical yet protective of human health and the environment. She conducts realistic assessments and calculates target cleanup levels based on site-specific exposure scenarios. Her work has involved pesticides, heavy metals, solvents, and petroleum-contaminated soils. She assists multiple school districts in California with site assessment, public relations, and the Department of Toxic Substance Control school site approval process. She participates in public hearings and school board meetings and coordinates her projects with the California Environmental Quality Act (CEQA) process.

Before joining PlaceWorks, Denise managed large divestiture environmental due diligence projects for the electric power industry and was involved in numerous environmental projects for oil field operation. Her experience also includes the development and testing of risk assessment software and teaching training courses in risk assessment using the different software programs.

Stuart Michener, PG, REA
Senior Geologist

On very short notice, Stuart organized and implemented a rapid turn-around environmental support effort for the City of Seal Beach, which had just learned of the widespread presence of asbestos-containing material (ACM) in an old elementary school building. The school was being leased by the city, and part of this building was occupied by a popular child-care center. This fast-breaking information soon became the subject of intense community concern.

Stuart quickly formed a project team, including his risk assessment and industrial hygiene colleagues at PlaceWorks, and immediately set in motion a sequence of responses–a site inspection, followed by sampling for ACM and lead paint residues, then appropriate laboratory analyses, and finally, a report that was presented in person as a briefing to the head of the City’s Public Works Department. The team recommended that the day-care center be temporarily closed so that potentially hazardous materials could be abated, after which, the day-care center could be safely re-occupied.

Stuart and his team testified before the City Council, where the test findings, the temporary day-care center closure, and potential health risks were explained in lay terms to the Council and a standing-room-only City Hall. After the meeting, Stuart and team met with more than two dozen parents who expressed their relief that the City was handling the situation in a proactive, thorough, and responsive manner.

Stuart has devoted more than 30 years to the practice of environmental assessment and related mitigation measures. Starting at the age of 15, when he was selected to participate in the annual Patrick Henry Public Speaking Competition in Washington DC, he has harbored a love for both written and oral communication. Not infrequently, his projects have been high-profile in nature, sometimes warranting television or front-page newspaper coverage.

Karl Rodenbaugh, DEnv
Senior Scientist


Karl has communicated environmental risks of various types to a range of decision making bodies and stakeholders, including:

  • Recycled wastewater safety. Treated wastewater was proposed for use as irrigation at several schools. Karl studied potential pathogenic and chemical risks and presented results before the Board of the Fillmore Unified School District. Following the presentation, the Board voted to approve the project with recommended provisions.
  • EMF radiation risk. A cell tower was proposed on a school site. Karl’s presentation to the board of the Santa Ana Unified School District evaluated the cell tower’s risk from two perspectives: 1) whether “scientific proof” of adverse health effects exists and 2) consideration of the “precautionary principle.” The Board members that voted for the project cited the absence of scientific proof; those that voted against cited the precautionary principle.
  • Toxic air risk. An existing oil processing facility produced visible and odorous air emissions in a residential neighborhood. Karl performed a health risk assessment and evaluated facility operational parameters. Findings were presented at a community forum with local television media. The presentation helped stakeholders distinguish real and perceived risks.
  • Wildfire hazard. Long Beach Unified School District (LBUSD) operated a 13-acre and 40-structure outdoor science center (Camp Hi Hill) for fifth-grade students deep in the Angeles National Forest (ANF) that was subject to uncertain hazard from uncontrolled wildfire. In 2007/2008 two fire hazard assessments were commissioned to evaluate the fire risk, and an evacuation plan was prepared in response to worst case fire scenarios. Karl communicated the risks and evacuation plan to LBUSD executives and camp staff in a series of meetings. As a result, aggressive tree and brush removal was implemented and, in October 2008, the camp was closed to students due to elevated fire safety concerns. By September 2009 the massive Station Fire in the ANF had burned in all directions for miles around and up to the edge of the camp. On September 3, 2009 the Long Beach Press Telegram reported: “The U.S. Forest Service attributed the camp’s being spared to brush clearing that the district previously performed….”

In Karl’s experience, a comprehensive and detailed understanding of risk assessment methods and site-specific data is necessary – but not sufficient – for effective risk communication. A clear and concise summary of findings also is necessary so that decision makers and stakeholders can present and defend the results to others.

Karl has 31 years of professional experience performing environmental investigations and assessments for public and private entities.

Sponsored by: PlaceWorks