JAG Consulting Group, Inc.
Providing Innovative In-Situ Remedial Strategies
Expert Witness and Expert Consulting Services

Gary Cronk, President of JAG Consulting Group, Inc,
provides expert consulting and expert witness
services for attorneys, insurance companies, adjustors, paralegals, law librarians, legal secretaries, environmental consulting companies, and public entities. Mr. Cronk has provided litigation services for both the plantiff and defendant. Mr. Gary Cronk has over 30 years experience in conducting hazardous waste contamination investigations, brownfield redevelopment, chemical safety hazard assessments, design/operation of environmental remediation systems, and expert witness testimony.


Mr. Cronk provides the following Expert Consulting
and Expert Witness services:

• Soil Contamination Issues
 • Groundwater Contamination Issues
• Surface Water Pollution Issues
• Brownfield Redevelopment Issues
• Property Due Diligence Issues
• Hazardous Materials Management Planning
• Toxic Tort Cases
• Site Remediation Cost Evaluation
• Chemical Hazards and Safety Issues


The following is list of Expert Consulting and Expert Witness Cases in which Mr. Cronk has been involved in:

Improper Disposal of Hazardous Waste (2011). Provided an expert report, sworn deposition, and litigation support for the Plaintiff regarding the improper disposal of a liquid hazardous waste by a retail department store. Issues addressed included identification of hazardous waste characteristics and improper disposal of hazardous waste in a non-hazardous waste landfill. Client: Sean T. O’Bryan (Attorney at Law).     

Septic Tank Leakage and Contamination (2009). Provided litigation support for the Plaintiff regarding an uphill neighbor’s septic tank leakage at a residential site in Sherman Oaks, CA. Release of bio-hazardous septic wastes caused spread of potential pathogenic micro-organisms and foul odors onto the Plantiff’s property.  Developed a soil remediation plan to destroy the pathogenic organisms and eliminate odors.  Client:  Kneafsey, Tostado & Associates (Law Firm).   

Upper Santiago Creek Pollution Case.  Provided litigation support, an expert report, and sworn deposition for the Plaintiff regarding a neighboring property’s contribution of water pollutants to Upper Santiago Creek. Issues addressed included beneficial uses and water quality objectives for Santiago Creek, pollutants derived from a green waste operation, and treatment options and cost estimates. Client: Bridi & Seal (Law Firm).
Soil Contamination and Remediation at an Industrial Property. Provided litigation support and an expert report for the owner of an industrial property (Plaintiff) in La Mirada, CA that had been contaminated with VOCs and petroleum hydrocarbons. Issues addressed included delineation of the lateral and vertical extent of VOC contamination, VOCs released into the air during excavation inside the building, and the sufficiency of a prior Phase I Environmental Site Assessment. Client: Law Offices of Rueben, Raucher & Blum.  

Soil and Groundwater Contamination at a Gasoline Station Site. Provided litigation support and an expert report to the Owner of the property (Plaintiff) operated as a gasoline station in Buena Park, CA for more than 30 years. Issues addressed included offsite migration of MTBE groundwater plume, declining efficiency of remediation systems, and cost estimate for obtaining closure of the site. Client: Law Offices of Theodore A. Anderson.   
San Gabriel Valley Groundwater Site Superfund Case. Provided litigation support, an expert report, sworn deposition, and trial testimony in Superior Court for the Defendant regarding the liability and percent contribution to soil and groundwater VOC contamination at a potentially responsible party (PRP) site located in the El Monte Operable Unit of the San Gabriel Valley Superfund Area. Client: Prenovost, Normandin, Bergh & Dawe (Law Office).

Port of Oakland Brownfield Redevelopment Project. Provided written expert opinion for a 64-acre brownfield re-development project in the Port of Oakland, CA. Issues addressed included adequacy of soil contamination assessment, health impacts on site workers and future site users, impacts on biological resources, adequacy of site remediation activities. Client: M.R. Wolfe & Associates (Law Office).

Toxic Tort Case. Provided expert witness testimony at a Workers Compensation case regarding a chemical company’s policies for handling of highly corrosive chemicals and maintaining a safe work environment. Client: Teresa Edrington, Attorney at Law

Dana Point Harbor Water Pollution Case. Prepared a written expert opinion regarding discharge of gasoline from jet ski operations into Dana Point Harbor and whether the discharge was a violation of State water regulations. Client: Sterling Scott Winchell, Attorney at Law.

Elk Hills Power Plant Project. Prepared an environmental impact assessment for the Elk Hills Power Project's Application for Certification and testified at adjudicatory hearings before the California Energy Commission on controversial issues related to handling of petroleum hydrocarbon contaminated soil, hazardous materials management, and water supply impacts. Client: Downey, Brand, Seymour & Rohwer (Law Office)

Soil Contamination Assessment Services. Provided litigation support services on the Pacific Metal Craft site in Bell Gardens, CA. Conducted a soil sampling investigation and provided written opinion regarding PCE contamination at site. Client: Charles E. Whisonant, Attorney.

Superfund Site Remediation Cost Evaluation. For a confidential client, Mr. Cronk provided an independent evaluation of remediation cost estimates for the Waste Disposal Inc. Superfund site. Mr. Cronk provided an updated present day worth cost estimate for the following alternatives: RCRA hybrid cap with passive venting system, full RCRA cap, and off-site incineration.

Soil and Groundwater Contamination Assessment. Provided expert opinion regarding gasoline contamination resulting from a leaking UST at a gas station site in San Clemente, CA. Conducted an offsite soil sampling investigation and provided written opinion regarding the source of contamination and potential offsite migration. Client: Ernest Brown & Company (Attorneys).

Testimony at Water Resources Control Board Hearing. Provided consulting services and expert witness testimony on water quality impacts resulting from diversion of streamflow from the Lower Mokelumne River at legal hearings before the California Water Resources Control Board in Sacramento, CA (San Joaquin County vs. East Bay Municipal Utility District).

Testimony for Biomass Cogeneration Project, Fresno, CA. Provided engineering consulting services for the design of an evaporation pond, regulatory permitting, and Environmental Impact Report for the Jaoudi Biomass Cogeneration Project near Fresno, CA. Provided testimony on water quality, hazardous waste handling, and groundwater protection at a hearing with the California Attorney General's Office.

Testimony for California Power Plant Energy Projects. Provided environmental impact assessment and regulatory compliance for disciplines of water resources, water quality, hazardous materials handling, and hazardous waste management for several major energy project applications submitted to the California Energy Commission. Testified at adjudicatory hearings. Client: California Energy Commission.

Contact Us

Gary Cronk

Office Phone: 714-241-7722
Office Fax: 714-241-9922
Cell Phone: 714-465-7767
e-mail address:

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