
- Who We Are -
Jim Taylor, P.G.
Geologist, President and Founder of TGS
Jim has a Geoscience Degree from Penn State University and Master of Environmental Pollution Control from Penn State Great Valley. Prior to putting his name on the door of TGS, Mr. Taylor worked with the US Bureau of Land Management, PA Department of Environmental Protection, a mid-sized environmental engineering firm, and a small local engineering firm. His 35-year plus career in geology and environmental consulting has encompassed a wide range of disciplines, clients and unique projects. Major areas of expertise are contaminant characterization and remediation, environmental risk management, drinking water supply, nitrate modeling and land use planning. Jim is a registered Professional Geologist in Pennsylvania and Delaware. Most who know him agree, all work and no play has never been an issue, most likely taking him outdoors on a run, mountain bike ride or adventure, or living the wannabe rockstar dream in an old man band.
Andy Sokol, P.G.
Geologist, Vice-President, Senior Principal
Mr. Sokol has over 30 years of professional experience with landfills, geologic characterizations, PA Act 2 compliance, emerging contaminants and innovative sample collection methodologies. Andy has extensive experience and expertise with solid waste landfills, including expansions, compliance, operations, and deciphering complex geology and hydrogeology in the Triassic Basin. He manages insurance claim projects involving tractor trailer accidents; resolving spills and conducting expedited cleanups to mitigate environmental exposure in a cost-effective manner. Andy has a degree in Geology from Penn State and is a registered Professional Geologist in Pennsylvania and Delaware. He has been an active member of the American Institute of Professional Geologists (AIPG), also having served many roles for the Pennsylvania Section. The western PA farm boy can be easily spotted in 'Big Red' the Dodge Ram, and on those occasions where he rumbles away from the landfill, there is likely a kayak or bike in the truck bed headed to the lake.
Mike Napolitan, P.G.
Geologist, Senior Project Manager, Principal
Mike has over 20 years of consulting experience and is a registered Professional Geologist in Pennsylvania and Delaware. His technical background includes geology and hydrogeology investigations of large-scale corrective action projects, advanced technologies, landfills, water supply, resource exploration, GIS, modeling, geothermal testing, and geophysics. Mike has used GIS to site water supply wells, geo-forensics, and manage complicated site details. He has become an expert in GIS mapping and relational database and has authored papers and given presentations on the subject. Mike has his FAA unmanned aircraft pilot license and can aerially map sites, reproduce stunning visuals, and perform complex analytics using point-cloud modeling. Mike has an Earth Science degree from Penn State, and Master in Applied Geology from the University of Pennsylvania. He's the smart one, has been said by many a client. Mike is very involved volunteering in local organizations, and as a youth coach for softball and baseball. Word has it Mike has developed his own 3D trajectory calculator for pitching and batting and is ready to relationally database all the acorns in the McKaig Nature Center.
Bill Gothier
Senior Scientist, Project Manager
Mr. Gothier has over 20 years of experience in consulting and local government. Bill graduated from Shippensburg University with a degree in GeoEnvironmental Studies. His skill set includes wide-ranging landfill compliance, stormwater management, spill response and mitigation. Bill is a key manager for many of our field services and environmental cleanup actions and has become an invaluable mentor to the younger staff. Before coming to TGS many years ago, Bill was at the County Soil Conservation District, gaining extensive knowledge in watershed planning, restoration, stream bank stabilization, stormwater management, grant writing, and permit compliance. We suspect it is there, or probably college, that he grew his passion as a board gamer. Monday mornings are filled with the tall tales of his amazing strategies and battles won at the weekend convention.
Carol Jerrahian
Senior Administrator.
For over 15 years Carol has been brightening our office and using her wealth of experience from the corporate marketing and travel days. She is the oil that keeps the wheels running smooth and the conductor to keep us on the track. If you need any information or have questions regarding operations, billings, A/P, A/R, or just how to throw a great holiday party, please feel free to reach out to Carol.
Alyssa Schell
Project Manager, Scientist, Project Manager
Ms. Schell has a degree in Environmental Science from Muhlenberg College and Masters in Environmental Protection & Compliance Management from Saint Joseph University. Alyssa manages complex projects involving yearlong sampling events, data collection, analysis and compliance. Ms. Schell has become a leading resource on Emerging Contaminants and particularly PFAS/PFOS. Adept with many hats, she technically assists with all aspects of the company including landfill compliance, groundwater sampling, site characterization, field investigations, and environmental site assessments. Her emphasis and passion are on environmental protection and safety management, which complements our industrial compliance and health and safety services. Alyssa developed OSHA training courses and then seamlessly migrated them to virtual classes, as she navigated us all knowledgeably and safely through Covid. As an all-star collegiate softball player, she is our ringer for corporate softball games. If we only had some other talent to back her up.
Mikaela Inforzato
Geologic Scientist
Mikaela has a B.S. in Geology from California University of Pennsylvania. Ms. Inforzato is a Licensed Geologist in Training having over 4 years of experience in geology, environmental science, and geographic information science. Her primary areas of expertise include geologic & hydrogeologic characterization, logging wells, aquifer testing, landfill regulatory compliance, water quality sampling, environmental monitoring, GIS mapping, and data management. Quietly confident and intelligent, rumor has it, Mikaela is also a deft board gamer. Around the office, the debate over best geology board game rages on, Erosion, Stonemaier or Crystal Crush!
Jacob Rebisz
Geologic Scientist
Jacob has a B.S. in Earth Science from Dickinson College. Mr. Rebisz has 2 years of experience in geology, environmental science, and field services. His rolls include water quality sampling, environmental monitoring, subsurface evaluations, remedial oversight, system operation & maintenance, site assessments and construction monitoring. Grizzly Jake, who was big and bold enough to buy a truck larger than 'Big Red', quietly and confidently gets 'er done with a big smile and his dog by his side.
Derek Yoder
Staff Scientist
Derek has his B.S. in Geography from Millersville University. Mr. Yoder has 2 years of experience conducting field services, water quality sampling, GIS map making, environmental monitoring, remedial oversight, system operation & maintenance. Mr. Yoder is an active member of the Pennsylvania National Guard, and has served two In-Country Deployments, including Acting Team Leader during the 2020 D.C. Inauguration. Derek is respectfully known in circles as 11 Charlie Mortarman and Army Infantry, although around the office we just say he likes to blow stuff up.
Ed Claypoole, NJ LSRP
Senior Manager, Scientist, New Jersey Licensed Site Remediation Professional (LSRP)
Mr. Claypoole received his B.S. in Environmental Science from Stockton University and Continued Education from Rutgers University and Cook College. Ed is a licensed EPA/AHERA Asbestos Building Inspector/Management Planner, and NJDOH Lead-Based Paint Inspector/Risk Assessor. Ed has been in the environmental consulting field for over 30 years, and with that brings vast levels of experience in property redevelopment, building demolition and renovation, hydrogeological investigations, soil and ground water remedial activities, risk assessments, managing field schedules, field equipment, contractors, laboratory logistics, supervision and training's to staff, project management and budgeting. We just refer to Ed as the knower of all NJLSRP and NJDEP regulations and with the New Jersey ascent to back it up.
Celeste Takach
Staff Scientist
Celeste recently graduated from Bloomsburg University with a degree in Ecology, Conservation, & Field Biology. In school, Celeste focused her studies on freshwater systems of Pennsylvania. She is looking forward to assisting with the macroinvertebrate and water quality studies. Celeste has jumped in and quickly become adept with sampling, monitoring and data management. Possibly her biggest kudo to date was bumping in to 'her boss' at a concert after week one, and not telling embarrassing stories about him to her colleagues.
Sunshyne Hummel
Geologic Scientist
Sunshyne has a Geology degree from Kutztown University and Master of Science in Earth Sciences from Syracuse University. Her thesis focused on hydrogeology and geochemistry using isotopes to characterize formation waters in hydrocarbon basins. With her strong geochemistry knowledge and management skills, Sunshyne is a key player in our landfill services. Her current management position is as great mom & technical consultant. Sunshyne has also put her earth science and chemistry knowledge to use with a boutique line of natural healthcare products. It is why we all look and smell so good and healthy around the office.
Dennis Fisher
Scientist, Technical Consultant
Mr. Fisher, with over 30 years of consulting experience, has incurred a wealth of knowledge in the environmental field with a multi-disciplined array of talents. Field investigations, sampling, regulatory compliance, asbestos surveys, mold inspections, USTs, and ESAs are just a few of his specialties. He also provides technical support, compliance assistance, and special waste acceptance. Dennis graduated from Millersville University with a degree in Geography and minor in geology. Among Dennis' many talents are being a connoisseur of hot wings, Biolo, Halupkies and other regionalism's of the central PA CoalCrackers. Dennis may be counting diatoms and sand grains on the Florida gulf coast, but his mystery teleport window will always remain open here.
Resumes

- Jim Taylor
- Andrew Sokol
- Michael Napolitan
- William Gothier
- Alyssa Schell
- Mikaela Inforzato
- Jacob Rebisz
- Derek Yoder
- Ed Claypoole
- Sunshyne Hummel
Published Papers
TGS Employees are authors, presenters and trainers on numerous topical subjects. A listing of Referenced Subjects are provided on our web site. We encourage you to peruse and use any of the material and please feel free to contact any one of us for copies or to discuss topics in greater detail.
