Eureka   (707) 443-5054   |   Ukiah   (707) 462-0222   |   Santa Rosa   (707) 525-1222


Engineering Geology, Geotechnical Engineering, and Hydrogeology

One of our Engineering Geologists performing a geotechnical evaluation in Del Norte County, California
We provide geotechnical engineering and engineering geology services from our offices in Santa Rosa, Ukiah, and Eureka, California. Our Geotechnical Engineers and Certified Engineering Geologists have a deep understanding of and accomplishments in seismic hazard evaluation, landslide mapping, liquefiable soils, expansive soils, and hydrogeologic studies. Whether you are developing plans for a new structure or mitigating potential hazards that threaten your project, an exploration and analysis of subsurface conditions will minimize your risks as well as your costs for design and construction. Our work has been reviewed and accepted by the California Geologic Survey, City and County chief building officials, State Office of Mining and Reclamation, and Regional Water Quality Control Board staff. Your projects will benefit from our in-house materials laboratory, drilling rig, and creative use of technology.
Our comprehensive services include:
  • Engineering geology
  • Soils and foundation engineering
  • Permitting support
  • Geologic hazards assessments
  • Geologic mapping
  • Slope instability evaluations and landslide mitigation
  • Earth retention systems design
  • Geotechnical reports
  • Grading observations
  • Liquefaction analyses
  • Retaining wall recommendations
  • Soil stabilization/winterization design recommendations



  • River underflow studies
  • Wastewater effluent fate and transport studies
  • Water resource evaluations
  • Water well design and siting
  • Aquifer characterization


Fault Characterization

  • Paleoseismic fault assessments
  • Alquist-Priolo fault hazard assessments
  • Fault rupture setback assessments


Geotechnical Characterization

  • Subsurface analyses
  • Liquefaction evaluations
  • Foundation evaluations
  • Site development recommendations
  • Aquifer characterization
  • Geotechnical reports
  • Grading observations
  • Retaining wall recommendations
  • Soil stabilization/winterization design recommendations


Engineering Geology

  • Landslide mapping and monitoring
  • Alquist-Priolo fault hazard investigation
  • Slope stability analyses
  • Timber harvest plan engineering geologic studies
  • Naturally occurring asbestos evaluations
  • Hard rock quarry evaluations
  • Sediment and erosion control
  • Septic system investigations and septic suitability evaluations
  • Reconnaissance level geohazards review
  • Aerial photo interpretation and analysis