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Image 01Mostafa El Sehamy, P.G., C.G.W.P., C.E.M.
President, Senior Hydrogeologist


Mr. El Sehamy has over Twenty (20) years of experience in hydrogeology and environmental engineering, involving such activities as groundwater investigation, water quality modeling, ground and surface water quality analysis, environmental impact assessment, remediation design of replacement of domestic well systems in contaminated areas; acquifer sensitivity studies for hydrocarbons and solvents and soil and groundwater investigations of leaking underground storage tanks and pilot venting studies. Mr. El Sehamy has designed over 50 remediation systems for the New York State Department of Environmental Conservation (Oil Spill Prevention) and private sectors. The remediation system involved several techniques, such as pump and treat, soil venting, air sparging, bio-remediation and bio venting. Mr. El Sehamy has also conducted several remedial investigation/feasibility studies in New York State.



Representative Occupational Experience

Groundwater and Hydrologic Modeling  
Groundwater flow and contaminant transport, modeling utilizing MODFLOW, PLASM, MODPATH and WHPA. Hydrologic modeling utilizing HELP. Assessing model inputs and outputs, boundary and initial conditions, model calibrations, verification and sensitivity analysis and performing analytical checks.  
Hydrologic studies and water analysis.

Environmental Site Assessments  
Conducted Phase I and II Environmental Site Assessments, analysis of site investigation reports, identifying contamination locations and sources. Gas Chromatograph analysis and water sampling, analyzing laboratory results for QA/QC, magnetometer surveys for locating buried drums and underground  
storage tanks (USTs), estimating UST and other subsurface leaks, septic tank cleanup inspection, liability assessments and estimating costs to attain compliance.

Expert Witness  
Offered expert witness testimony for the New York State Department of Environmental Conservation (NYSDEC) and several private sector cases.

Environmental Impact Statements  
Conducted and supervised several environmental impact statements for shopping centers in the states of New York and North Carolina.

Solute Transport Modeling  
Conducted groundwater flow and solute transport modeling at Superfund, municipal, industrial and water supply sites impacted by organic/inorganic hydrocarbons, PCBs, and metals. Developed strategies to contain and clean-up aquifers, protect water supply wells, and prevent impacts to surface water bodies, including containment of free phase product recovery. Analytical and numerical models, such as PLASM, MODFLOW, Random Walk, Quickflow, Flowpath and Groundwater Path were used.

Risk Assessments  
Delineated dissolved petroleum hydrocarbon plume and implemented a risk assessment regarding a subsurface storage tank release into the Long Island Aquifer.

Engineering Compliance  
Auditing manufacturing plants, assessing plant-wide environmental conditions, identifying and providing solutions to present and potential RCRA wastes and other environmental problems, SARA Title III calculations, environmental inventorying, compliance status and potential impact analysis of waste disposal practices, air compliance analysis, insurance claims analysis and preparing work plans and engineering reports.

Remedial Investigation and Feasibility Studies  
Oversight/planning of site investigations; data analysis, including statistical analysis and geostatistical contouring utilizing SURFER and GEOSOFT/KRIGING; performance of feasibility studies, including  
technology evaluations and screening, alternatives development and evaluation and cost estimations.

Due- Diligence Programs  
Designed and implemented due-diligence programs (ranging from Phase I Assessment to Comprehensive Hydrogeologic Investigations) to assess environmental liabilities for numerous land development clientele.

Delineation of Chlorinated Organic Plumes  
Supervised the delineation of a dissolved chlorinated organic plume from underground tank loss. Developed a remedial action program in accordance with New York State regulatory guidelines to abate soil and groundwater contamination.

Research Projects   
Conducted groundwater studies with Nassau County Department of Public Works to investigate the impact of heating oil and solvents on public supply wells in the Levittown and Glen Cove areas of New York State.

Remedial Action  
Prepared remedial action plans. Designed and implemented hydrocarbon remediation systems for soil and groundwater.

Pump Test Aquifer Analysis  
Conducted several pump test aquifer analysis and field coordination in relation to water supply feasibility studies for the New York City Transit Authority.

OSHA Instructor  
Instructed several courses, such as OSHA 40 Hours Right to Know, CPR, 8 Hour OSHA Refresher, Fall Protection, Confined Space Entry and Lockout/tag-out. Developed safety programs for confined space and  
accident investigations.

Hazardous Waste Remediation Sites  
Project Manager – RI/FS, pre design investigation, remedial design, construction oversight of the remedial action, and operations and maintenance of the soil vapor and groundwater treatment systems. Each RI/FS was performed under the direction of NYSDEC