Program Committee

The RACIE Conference Committee is comprised of researchers and educators throughout the world who have been working in the field for many years. The committee is dedicated to the dissemination of information that can assist in the improvement of research for decades to come. They have taken the time to ensure all information presented at this conference is of the highest quality, as well as relevant and scientifically accurate.

Technical Planning Committee

Greg Bazley

US Environmental Protection Agency Region 9 (RMP - EPCRA - CERCLA)

Greg Bazley is with US EPA Region 9’s Superfund and Emergency Management Division. Current projects and interests are focused on emergency preparedness and the ability for local responders and industry to respond safely and efficiently. The majority of the past 10 years with US EPA, Greg’s career has focused on process safety and risk management under EPA’s Chemical Accident Prevention Program, where he inspected refineries, chemical plants, and other facilities using hazardous chemicals.  

Russ Bennett

California Air Resources Board

Over 15 years experience in air, water, hazardous waste, and risk management regulations in complex industrial environments. Served as environmental protection contact for operations, supervisory, and managerial staff. Excellent ability to research and apply technical environmental laws and regulations to existing or planned industrial processes. Skilled at organizing large quantities of environmental protection data to ensure it is collected, organized, analyzed, and reported per strict policy and regulatory requirements. Strong mechanical aptitude when hands-on work required.

Joe Chang


Dr. Joseph Chang has 30 years of experience in diverse subject areas in atmospheric sciences (e.g., atmospheric modeling, dispersion/plume modeling, environmental impacts, climate change, data analysis, and model verification and validation) and in homeland security (e.g., transportation security, border security, immigration, chemical security, infrastructure protection, risk assessment, operational and statistical analysis, and performance measurement). He provided technical management for the Department of Defense Office of the Special Assistant for Gulf War Illnesses to assess the potential exposures to U.S. troops due to inadvertent chemical agent releases during the 1991 Gulf War. He developed the Hybrid Plume Dispersion Model and the Offshore Coastal Dispersion Model. He also developed for the DOE, uranium enrichment plants a dispersion model that accounts for complex thermodynamics and chemistry of uranium hexafluoride. He evaluated more than a dozen commonly-used dense-gas dispersion models that are primarily used to model accidental releases of toxic industrial chemicals. He also extensively evaluated DoD dispersion models, such as the Joint Effects Model and the Hazard Prediction Assessment Capability. The evaluation methodology and acceptance criteria that he co-developed for dispersion models are widely used by scientists throughout the world. He has been hosting the annual George Mason University Conference on Atmospheric Transport and Dispersion Modeling for more than 15 years. Dr. Chang published over 24 articles in peer-reviewed journals and co-authored one book, Guidelines for Use of Vapor Cloud Dispersion Models. He is a Certified Consulting Meteorologist by the American Meteorological Society. He has also served on various AMS boards and committees, including co-chairmanship of an AMS committee to explore a new climate-change consulting certification program.

Jessica Cox

DHS S&T Chemical Security Analysis Center (CSAC)

Ping Di         

California Air Resources Board

Pingkuan (Ping) Di is the manager of the Meteorology Section of California Air Resources Board (CARB).  Ping manages the Smoke Management and Toxic Air Modeling programs for CARB.  He has over 30 years of experience in diverse environmental areas in air quality and toxics modeling (e.g., air dispersion/plume modeling, photochemical modeling, receptor modeling), health risk assessment, regulatory development, environmental impacts assessment, air pollution control, climate change, data analysis, etc.  He has authored and coauthored over two dozes of peer reviewed journal papers. 

Ping has a Ph.D. degree in Civil and Environmental Engineering from UC Davis, and he is a registered Civil Engineer in California.


California Air Resources Board

Dr. Walter Ham is the manager of the Advanced Monitoring Techniques Section in the Monitoring and Laboratory Division of the California Air Resources Board. His work utilizes both traditional and emerging monitoring methods such as mobile platforms, remote sensing, and air sensors to characterize air quality at the community scale. He obtained his Bachelor of Science degree in Biological Engineering from the University of Georgia and Doctor of Philosophy degree in Civil and Environmental Engineering from the University of California, Davis.

Kathryn Lawrence    

US Environmental Protection Agency

Kathryn (Kay) Lawrence is the manager of U.S. EPA Region 9's Emergency Prevention and Preparedness programs covering California, Arizona, Nevada, Hawaii and the Pacific Trust Territories. The Region 9 Clean Air Act Risk Management program and the Emergency Planning and Community Right to Know Act (EPCRA) Emergency Planning Regulations are within her program operations. Kay also manages the Emergency Preparedness Team for the EPA San Francisco office. EPA shares responsibilities with the U.S. Coast Guard and FEMA in federal response planning and in partnering with federal, state and local response planners for hazmat, oil, disaster and other emergency response related readiness efforts.

Prior to her current position, Kay was an On Scene Coordinator in EPA’s Emergency Response Program where she oversaw and directed federal efforts in response to hazardous materials incidents, oil spills and pollution impacts related to natural disasters.

Kay has a Bachelor of Science in Chemical Engineering.

Alan Lloyd

University of Texas at Austin

Dr. Lloyd is currently a Senior Research Fellow at the Energy Institute, University of Texas at Austin. The focus of his research is the role of hydrogen in a sustainable society, fuel cells, electric drive vehicles, renewable energy and policies to promote zero emissions vehicles.

Alan C. Lloyd served as the President of the International Council on Clean Transportation from 2006 until 2013. He is one of the founding members of the ICCT. The ICCT, sponsored by the William and Floral Hewlett Foundation, the Energy Foundation, and the ClimateWorks Foundation, has the goal of dramatically improve the environmental performance and efficiency of cars, trucks, buses and transportation systems in order to protect and improve public health, environment and quality of life.

Dr. Lloyd served as the Secretary of the California Environmental Protection Agency. Appointed by Governor Arnold Schwarzenegger in December 2004.  Among other initiatives, he required a review of the “State of the Science” of the six Boards and Departments composing the Agency in order to ensure that it met the quality required for sound policy making. Oversaw a budget of $1.5 billion and 4,500 employees throughout California. The mission of the California Environmental Protection Agency is to ensure public health, environmental quality and economic vitality in the State of California. It is composed of the following boards, departments and offices: Air Resources Board, Department of Pesticide Regulation, Department of Toxic Substances Control, Integrated Waste Management Board, Office of Environmental Health Hazard Assessment, and the State Water Resources Control Board.

As Secretary, Dr. Lloyd lead the Governor’s Climate Action Team (CAT) to develop a plan to implement the Governor’s aggressive Executive Order to reduce greenhouse gas emissions in California to 80% of 1990 levels. He chaired the California Greenhouse Gas Registry, was a member of the Oceans Protection Council, chaired the Environmental Justice Agency Working Group and was a co-chair of the Goods Movement Action Plan requested by Governor Schwarzenegger. Dr. Lloyd led the California Climate Change delegation at the United Nations Climate Convention in Montreal in 2005 and developed a Memorandum of Understanding in collaboration with Professor José Goldemberg to share experiences in reducing greenhouse gases in the states of São Paulo, Brazil, and California, United States.

Dr. Lloyd served as Chairman of the Air Resources Board, California Environmental Protection Agency, State of California.  Appointed by Governor Gray Davis in February 1999 and re-appointed by Governor Arnold Schwarzenegger in August 2004 before his appointment to Secretary. Oversaw a $150 million budget and a staff of nearly 1,000 employees located in northern and southern California.

Helen Mearns

DHS S&T Chemical Security Analysis Center (CSAC)

Helen Mearns is the Deputy Director of the Department of Homeland Security (DHS) Science and Technology Directorate (S&T) Chemical Security Analysis Center (CSAC).  CSAC is one of five DHS S&T labs under the umbrella of S&T’s Office of National Laboratories, which offers a centralized laboratory-based research, development, test and evaluation function for DHS.  S&T CSAC is the nation’s only federal studies, analysis, and knowledge management center for assessing the threat and hazard associated with an accidental or intentional large-scale chemical or chemical terrorism event in the United States.  Prior to coming to the S&T CSAC, Ms. Mearns worked for the Department of Defense Joint Chemical, Biological, Radiological, and Nuclear (CBRN) Defense Program Analysis Integration Office, where she served as the Principal Advisor to the Deputy Assistant Secretary of Defense (DASD) for Chemical and Biological Defense on matters of CBRN survivability.  Drawing from over 25 years of experience in Chemical, Biological, Radiological contamination survivability, Ms. Mearns, in coordination with the office of the DASD for Nuclear Matters, managed the Department of Defense CBRN Survivability Program.

Olga Pikelnaya

South Coast Air Quality Management District

Dr. Pikelnaya is a Program Supervisor at the South Coast Air Quality Management District, working on developing South Coast AQMD’s optical remote sensing (ORS) program and implementation of Refinery and Community Air Monitoring (Rule 1180). Prior to joining South Coast AQMD, Olga worked as a post-doctoral researcher at University of California Los Angeles, where she developed and deployed ORS instrumentation for monitoring of refinery emissions. Dr. Pikelnaya earned her Ph.D. in Atmospheric and Oceanic Sciences from UCLA. Her main research interests include implementing innovative instrumentation and measurements strategies for real-time emission monitoring and assessing the impact of industrial emissions on neighboring communities. 

Will Vizuete

University of North Carolina, Chapel Hill

Dr. Vizuete is an associate professor in the Environmental Sciences and Engineering department in the Gillings School of Public Health. In his research Dr. Vizuete seeks novel environmental engineering solutions to solve public health problems associated with air quality.

Greg Vlasek  

California Air Resources Board

Greg Vlasek was recently appointed as an advisor to CARB’s new Prescribed Burn Smoke Management Program in the Air Quality Planning and Science Division.  In this role he is responsible for managing CARB’s agricultural and prescribed burn meteorology forecasting team and for developing a proactive forestry prescribed burn monitoring and management system for California, under direction of the Governor’s Climate and Forestry Management Task Force.  He previously served in the CalEPA Office of the Secretary as the executive overseeing the Unified Program for hazardous material and hazardous waste management, and as the immediate past chair of the Interagency Refinery Task Force.  From 2007 to 2017, Greg worked at CARB as a legislative representative in the Office of the Chair and as chief of the emergency air monitoring program in the Monitoring and Laboratory Division. In that capacity, he co-authored the CARB-CACOA Refinery Emergency Air Monitoring Assessment Report published in 2017.  Prior to state service, he was a liaison to CARB and many other regulatory agencies on behalf of the natural gas industry.


University of California, Davis 

Dr. Wexler obtained his BS in Engineering Physics at UC Berkeley, MS in Mechanical Engineering at MIT and PhD in Mechanical Engineering at Caltech. His research interests relate to atmospheric aerosols, modeling their behavior, measuring their properties and understanding their health effects.

Greg Yarwood          


Dr. Greg Yarwood is an internationally recognized expert with over 20 years’ experience in atmospheric chemistry, air quality modeling, photochemical model development, and interpreting ambient air quality data and emissions inventory development, particularly for motor vehicles and biogenic sources. He directs air quality, meteorological and emissions modeling studies for clients in government and industry, with emphasis on photochemical air pollution issues, such as ozone, secondary particulate matter (PM), visibility and air toxics. Greg leads the development of Ramboll’s Comprehensive Air Quality Model with extensions (CAMx), and has implemented advanced modeling techniques for source attribution and sensitivity analysis, including OSAT, PSAT, DDM, HDDM and process analysis. He also designed the reactive tracer methodology used for modeling air toxics in CAMx. For USEPA, Greg developed the Carbon Bond 2005 (CB05) chemical mechanism that is used for ozone and PM in CAMx and USEPA’s CMAQ model. Greg holds a PhD in chemistry from Cambridge University. He is a member of USEPA’s Board of Scientific Counselors for the Clean Air Research Program.