Representative Projects

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Private Residence, Palo Alto, CA -   

Designed and oversaw a dewatering hydrogeological study for a new home with a planned basement in a shallow groundwater setting. The study, which involved aquifer testing and 3D modeling to calculate dewatering well spacing, depth, and flow rates, was approved without comments by the City of Palo Alto. Approval of the study resulted in cost savings of over $1M by avoiding construction of a subsurface groundwater cutoff wall. 

Mission Rock Development Project, San Francisco, CA -  Dewatering design to support street construction of a new mixed use development project along the San Francisco Bay. The design incorporated high resolution geologic modeling of the artificial fill and underlying Bay Mud interface and consisted of series of deep wells and french drains to achieve dewatering targets. Simulated flow rates were within 10 percent of observed flow rates in the field, demonstrating a highly accurate model that supported appropriate design of the onsite treatment system. 

La Bahia Hotel Development, Santa Cruz, CA -   Developed a solution to a groundwater control issue that had stalled the hotel development project for several years. Assisted the design team in evaluating long-term groundwater control options for the proposed construction into the subsurface of a steep hillside. Performed slug tests and short-term pumping tests to assess hydrogeologic conditions and constructed a 3D groundwater flow model to evaluate various groundwater control options. The design included a gravity-fed perimeter drain to prevent surficial flooding associated with the structure impeding groundwater flow, thereby eliminating the need for continual pumping from beneath the building. 

Biotech Company, Sunnyvale, CA -  Development of a dewatering design for commercial structure with subterranean parking and neighboring groundwater contaminant plumes. Entera incorporated results from rapid subsurface profiling techniques into a numerical model for optimization of the dewatering design, which included deep wells within a slurry wall to minimize mobilization of the neighboring plumes.

Sanitary District, San Francisco Bay Area, CA -  Designed a 3D groundwater flow model and dewatering plan to support construction of a pump station at a sanitary district near the San Francisco Bay. Entera incorporated several parameters into the model, including sheet pile permeability, leakage from a nearby canal, average groundwater elevations and gradients, and hydrostratigraphy. The model was used to calculate well spacing, depths, and anticipated weekly flow rates to achieve the desired dewatering level throughout the construction period. 

Private Residence, Palo Alto, CA - Design, implementation and analysis of aquifer testing that conformed with the City of Palo Alto's controlled groundwater pumping regulations for construction dewatering. Results were incorporated into a 3D groundwater model to calculate dewatering well spacing, depth and flow rates.

Mission Rock Development Project, San Francisco, CA - Development of Standard Operating Procedures for aquifer testing to support field staff, data reduction, and analysis of results that were later used in the dewatering design numerical model.

La Bahia Hotel Development, Santa Cruz, CA - Design, implementation, and analysis of slug testing in low transmissivity subsurface conditions. Results were incorporated into a 3D model to design a perimeter drain for flood control.

Operating Landfill, Vacaville, CA - Design, implementation, and analysis of aquifer tests to support design of groundwater extraction systems.  Optimization of extraction well design and operation to maximize removal of nitrogen compounds in groundwater within the constraints of an operating landfill setting.

Closed Landfill, Antioch, CA - Aquifer test design and analysis to evaluate plume capture behind a subsurface cut-off wall to support design of a full-scale, 3,500-foot long slurry wall.  

Energy Facility, Pala, CA - Aquifer test analysis on a water supply well located at a power plant to determine sustainable well yields and pumping effects on a nearby lake.

Energy Facility, Bend, OR - Aquifer testing on a water supply well to determine sustainable well yields to support energy facility operations.

Energy Facility, Oakland, CA - Aquifer test analysis to determine parameters for input into a groundwater flow model for an energy facility located adjacent to wetlands.

 Biotech Company, Sunnyvale, CA - Compilation of a subsurface geologic data base from hydraulic profiling tool (HPT) investigations and existing boring logs.  Construction of a 3D subsurface model that was later incorporated in to a groundwater flow model for dewatering system design.

Railway Site, Pittsburg, CA - Design and HPT and membrane interface probe (MIP) investigation to provide rapid vertical and lateral profiling of site hydrostratigraphy and carbon tetrachloride in groundwater.

Operating Landfill, Vacavile, CA - Implementation of HPT investigations to optimize delineation of nitrogen compounds within an operating landfill.

Former Dry Cleaner, Millbrae, CA - Compound specific isotope analysis (CSIA) to evaluate the source of off-site volatile organic chemicals in groundwater and the progression of monitored natural attenuation.

Closed Landfill, Antioch, CA - Evaluation of long term MNA monitoring at a complex site with a diffuse plume using CSIA and supporting geochemical parameters.  Streamlined monitoring from 40+ wells to 9 wells along the plume centerlines.

Former Manufacturing Facility, Montvale, NJ - Multi-aquifer evaluation using CSIA  to assess whether multiple sources may be contributing to a plume of trichloroethene (TCE).

Former Shipyard, Alameda, CA - Evaluation of laser-induced fluorescence profiles to provide rapid delineation of petroleum hydrocarbons in groundwater in preparation for source removal.