About Us

EES Consulting is a registered professional and management consulting corporation with offices in the metropolitan areas of Seattle, Washington and Los Angeles, California. Learn more about our management and staff.

Gary Saleba, Executive Consultant

Gary Saleba

As both a management and strategic planning consultant, Mr. Saleba provides overall quality control and insight for all of EES’ diverse project undertakings. As a founding member of EES, Mr. Saleba has over 35 years of experience with electric, natural gas, water, wastewater, and disposal utilities. He has overseen more than 400 cost of service and rate design studies and has provided expert testimony and opinion in over 200 proceedings before virtually all tribunals in North America. He also has acted as project manager and owner’s agent for the development of large electric generation resources. Finally, Mr. Saleba has apprised virtually all of EES’s clients in how to deal with fundamental changes in the energy and natural resource industries. These changes include increased competition, more emphasis on public input in major decision making, and strategic planning under an uncertain future. Mr. Saleba has a B.A. in Economics and Mathematics and an MBA in Finance.

Amber Gschwend, Managing Director

Amber Nyquist

Ms. Gschwend provides analytical expertise for EES in support of a wide range of economic and financial studies. Ms. Gschwend's experience includes benefit-cost studies, cost of service studies, rate design studies, integrated resource planning, forecasting, conservation potential analysis, energy efficiency measure and program analysis. Ms. Gschwend uses several tools for providing economic analysis including benefit-cost analysis, risk analysis, and econometrics and statistical analysis. Special areas of study include federal standards for evaluating benefits and costs of water supply and related resources according to the Economic and Environmental Principles and Guidelines for Water and Related Land Resources Implementation Studies (March 10, 1983). Ms. Gschwend has an M.A. from Simon Fraser University and a B.A. in Economics from Western Washington University.

Donald Tretheway, Managing Director

Donald Tretheway

Don Tretheway has over 13 years' experience in wholesale energy market design and policy. At the California Independent System Operator (CAISO), Don led development of market design enhancements including creation of the Western Energy Imbalance Market (WEIM), and explored further regional collaboration in the day-ahead market (EDAM). He was responsible for creating the 15-minute market, including GHG costs in wholesale markets; developing the original storage market model that provided the foundation of FERC Order No. 841; and introducing the flexible ramping product in the real-time market and imbalance reserves in the day-ahead market. Mr. Tretheway holds a Bachelor of Arts in Economics from University of California-Los Angeles, and a Master of Business Administration from University of California-Davis.

Howard Choy, Executive Consultant

Steve Andersen

Howard Choy has provided executive and strategic leadership for large-scale projects and portfolios throughout his 30-year career in the energy industry. He is recognized for creating and administrating Los Angeles County’s Office of Sustainability, and developing the Southern California Regional Energy Network (SoCalREN), facilitating clean energy project development for 150 public agencies in the region. He has particular expertise driving sustainability initiatives including energy efficiency, demand response, generation and storage. As board chair of the Local Government Sustainable Energy Coalition (LGSEC), Mr. Choy has assisted governments across California to participate in energy programs by the CA Public Utilities Commission, California Energy Commission, and CA Air Resources Board.

Gail Tabone, Senior Consultant

Gail Tabone

Ms. Tabone brings over 20 years of experience in the U.S. and Canada. Her primary areas of expertise are cost of service and rate design, particularly for regulated environments, and resource planning. These include providing expert testimony, completion and review of cost of service studies, rate options and impact analysis, load forecasting, cost-benefit analysis, integrated resource planning and RFP management. Ms. Tabone has consulted in numerous valuations and utility acquisitions. Ms. Tabone has an M.S. degree in Applied Economics from the University of Minnesota and has been with EES since 1988.

Russ Schneider, Senior Project Manager

Russ Schneider

Mr. Schneider is an established project manager and analyst with ability in financial planning, power supply, transmission, strategic planning, resource development, forecasting, risk analysis, smart grid, data management, and rate design. Russ has over 16 years of experience in the utility industry. He joined EES/GDS in 2017 and before that spent ten years as Regulatory and Senior Data Analyst for Flathead Electric Cooperative. Russ has a Bachelor of Economics from Reed College in Portland, Oregon and a Master of Engineering and Technology Management from Washington State University.

Scott Mahnken, P.E., P.Eng., Senior Civil Engineer

Scott Mahnken

Mr. Mahnken has 33 years of civil engineering experience in planning, design and construction of hydroelectric and other water resource projects. His primary role has been as design engineer for new and existing hydroelectric projects, dam rehabilitations, pipelines, and hydraulic structures. His responsibilities include field investigations, preliminary design reports, design criteria, cost estimates, final plans and specifications, and construction monitoring. Mr. Mahnken has served as Independent Consultant for FERC Part 12D Safety Inspections.

Seung Kim, P.E., P.Eng., Senior Electrical Engineer

Seung Kim

Mr. Kim has over 35 years of broad experience in electrical design and consultation. Mr. Kim is experienced in all phases of hydroelectric and power system design and implementation. Mr. Kim performs conceptual and feasibility studies, specification development, bid evaluations, and provides assistance during construction of projects. His areas of interest include switchgear, protective relaying and controls, transformers, SCADA systems, communications and instrumentation systems. Mr. Kim prepares procurement and technical specifications, one-line and three-line diagrams, control schematic and wiring diagrams, and equipment layouts. He holds B.S. and M.S. degrees in Electrical Engineering from the University of Washington and is registered in multiple States and in British Columbia.

Priyanga Natarajan, Associate Engineer

Priyanga Natarajan

Ms. Natarajan’s experience includes managing complex data sets and preparing energy analysis following calculations prescribed by various State Technical Reference Manuals. Her areas of expertise include performing electric utility cost of service analysis, load forecasting, rate design, evaluation of service policies and other financial matters, and supplemental research in energy efficiency and distributed generation technology. Ms. Natarajan has a Bachelor of Engineering in Instrumentation & Control System from PSG College of Technology in Coimbatore, India.