Trudy Johnston
Trudy is President and partner with Material Matters, and has over 29 years in the municipal and industrial wastewater processing and solids treatment and management field, with 25 years as a consultant. Her primary interests include developing innovative uses and strategies for residuals, optimizing solids processing, conducting solids master studies, assessing compliance with biosolids regulatory standards, data/sample collection and validation, evaluating and resolving odors from residuals, and water quality nutrient trading. She participated in the WERF study with UMASS to assess biosolids stability standards and authored the protocol for the AVSR testing. Trudy has a BS degree in Earth Science from Penn State and is a certified wastewater treatment operator. [Resume]

Dr. Robin C. Brandt, Ph.D, PE
Robin is Vice President of Research and partner with Material Matters. He had over 30 years experience in consulting in municipal, industrial, and food processing residuals. He is responsible for development of new initiatives and peer review of technical projects. He also serves as a project manager, officer, and partner with Material Matters, and serves as liaison on projects involving consultation with Pennsylvania State University faculty and other service providers. Robin directs the company’s efforts in site and product odor assessments, field trials and plot studies, and innovative projects such as deep row hybrid poplar reclamation projects. He has a PhD degree in Agricultural and Biological Engineering from Penn State and is currently a lecturer and director of the Odor Assessment Laboratory at Penn State. [Resume]

Stefan Weaver, CPSS
Stefan is a project manager and partner with Material Matters, with over 14 years of professional experience, mostly in biosolids and residuals management. He is an ARCPACS certified Professional Soil Scientist, responsible for conducting technical soil site investigations for beneficial use (agricultural and disturbed land) projects. His understanding of regulatory challenges allow him to be involved in a variety of projects focusing on innovative uses such as deep row hybrid poplar reclamation, mine reclamation, site qualification, site mapping, conservation planning, nutrient assessment, database validation, and interacting with regulatory agencies. Stefan has an MS degree in Soil Science from Penn State. [Resume]

Aaron Stephens, MS, EIT
Aaron is Vice President of IST and partner with Material Matters, responsible for data and information management projects. He began as a consultant for Material Matters in 2002 for the development of the Material Manager™ database for biosolids, and now serves as a project manager since 2006. He works with multiple industrial and food processing clients, and has project experience involving waste heat utilization, data visualization and mapping with GIS and KML, and large-scale feasibility analysis in conjunction with master planning. He is a problem solver, specializing in data analysis, software development, and numerical modeling. Aaron is an E.I.T. with an MS degree in Agricultural and Biological Engineering from Penn State. [Resume]

Jennifer Callahan, MS
Jenn is a project scientist with Material Matters, and has over nine years of experience conducting a variety of natural resource investigations, with over six years as a consultant. She is responsible for managing residuals and biosolids evaluation projects, biosolids-to-energy projects, nutrient management projects, product end-use marketing, and beneficial-use permitting. Jenn is also responsible for regulatory review, preparing environmental permit applications, and conducting natural resource investigations, including wetland delineations, stream classifications, natural community mapping, and protected species surveys. Jenn has a BS degree in environmental resource management and an MS degree in Environmental Pollution Control from Penn State. [Resume]

Kelly Brenner, EIT
Kelly is a water and wastewater specialist with Material Matters, and has two years of experience in environmental consulting. She is responsible for wastewater and biosolids treatment evaluation and optimization, residuals and nutrient analysis and management, data analysis, sample collection, site qualification, permitting, and reporting. She has also conducted various pilot, feasibility, and wastewater loading studies, and residual end-use studies, in addition to coordinating end-use programs for municipal and private clients. Kelly began as an intern with Material Matters and is now an E.I.T. with a BS degree in Environmental Engineering from Penn State.

Nance Fertich
Nance has more than 20 years of experience with writing, editing and producing public relations materials as Director of Community Relations for a mental health care system. In her current role as Office Manager for Material Matters, she provides administrative assistance to the professional staff members including producing business development pieces, providing support for project managers, preparing a variety of internal reports, and overseeing invoice generation. [Resume]