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John Siskowic

Sr. Geologist

John G. Siskowic is a California licensed Professional Geologist with over 15 years of experience in environmental and geotechnical consulting and engineering. Mr. Siskowic has been involved with geotechnical and environmental projects in southern California for the past 12 years, following his practicing in the San Francisco Bay Area for 3 years.

Mr. Siskowic formerly served as the Director of Geotechnical Services and as a Senior Project Geologist. Serving in this capacity, he was involved on hundreds of grading, foundation, and underground utilities installation projects. He previously served as the Project Geologist on a 280-lot site in Carmel Valley, California, where he was in charge of leach field location, percolation testing, and geologic hazards identification. The latter consisted of aerial photography interpretation, landslide delineation, detailed landslide mapping, and mitigation of landslide hazards.

Mr. Siskowic has also served as Senior Project Manager for environmental site assessments and environmental cleanups at numerous service stations, dry cleaners and other industrial/ commercial properties. Mr. Siskowic has prepared multiple Work Plans, Remedial Action Plans and Site Conceptual Models as directed by various regulatory agencies, and is experienced with regulatory negotiation in several states. In addition, Mr. Siskowic has performed multiple complex subsurface investigations related to hydrocarbon and VOC releases, UST and hydraulic lift removals, and raw sewerage releases, with an emphasis on bringing sites to Regulatory Closure.

Understanding and delineating the horizontal and vertical extent of contamination and developing conceptual site models is one of Mr. Siskowic’s most valuable strengths. He has experience in evaluating subsurface soils and bedrock and contaminants in soil, soil vapor and groundwater in the context of real estate transactions, release investigations and remedial and regulatory compliance. Mr. Siskowic has extensive experience in project plan cost estimation and in the delineation of contaminants in soil and groundwater using various soil and groundwater sampling methods. By collecting quality data in the field, Mr. Siskowic is able to provide meaningful remedial cost estimates for contaminated properties. Mr. Siskowic’s Areas of Expertise include the following:

  • Geotechnical Field Testing for conformance with Geotechnical Recommendations; Geotechnical Laboratory Testing; Geotechnical Field Investigations
  • Design and implementation of numerous Phase II and Site Characterization soil, soil vapor and groundwater investigations for a variety of suspected contaminants for due diligence and liability purposes
  • Regulatory negotiation, design, cost estimating, implementation and project management of numerous soil and groundwater investigations and remediation projects in conjunction with regulatory agency directives.
  • Design, regulatory correspondence, project management, execution and reporting on hundreds of UST removals and contaminated soil over-excavation projects.
  • Preparation of Remedial Action Plans/Workplans, Progress Reports, Site Conceptual Models and Summary/Closure Reports for site investigations and site cleanups under the oversight of various regulatory agencies inside and outside California.
  • Geologic Inspections for real estate transactions of hillside homes and Forensic Manometer Surveying of distressed structures.
  • Soil Excavation and Replacement; Remediation by various methods; Providing Remedial Cost Estimates.
  • Water Intrusion Investigations
Team: EFI Global - USA
Location: California, Los Angeles, United States
Areas of expertise: Engineering, environmental and fire services
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