Tom Carpenter – Executive Director
Liz Mattson – Outreach Director
Kathryn Sain – Communications & Development Director
Nikolas Peterson – Staff Attorney
Lori Mitchell – Finance Manager
Emily Bays – Program Assistant

Tom Carpenter, Executive Director


Phone: 206-292-2850 x22
Tom Carpenter Tom Carpenter is the Executive Director of the Hanford Challenge.  He brings decades of experience in organizing, litigating, and policy oversight in the nuclear field, much of it devoted to Hanford.  He is an attorney, a graduate of Antioch School of Law, and has a Masters in Organizational Design and Renewal from Seattle University.

Tom worked as the Director of the Nuclear Oversight  Campaign for the Government Accountability Project from 1985 to 2007.  He founded Cincinnati Alliance for Responsible Energy (CARE) , which challenged plans to open the defect-ridden Zimmer Nuclear Power Plant.  Tom also served on the Cincinnati Mayor’s Environmental Advisory Council.

Through his work at GAP and Hanford Challenge, Tom has visited dozens of nuclear sites in the U.S. and Russia, hosted international conferences on protecting nuclear whistleblowers and examining the legacy of highly-contaminated nuclear facilities, and focusing on the Hanford Nuclear Site in southeastern Washington State.

Tom helped establish and is a Board member of the Hanford Concerns Council  (and its predecessor, the Hanford Joint Council) to mediate and resolve difficult and complicated issues relating to Hanford.

Tom has represented numerous whistleblowers and workers at various nuclear sites around the nation, including at commercial and military nuclear production facilities, such as Hanford, Los Alamos, Knolls Atomic Power Lab, Pantex, Lawrence Livermore, Fernald, Mound and others.  He has authored numerous reports and articles on the effects of nuclear production on workforce health and safety and the environment, and established and participated in independent environmental sampling programs at Hanford, Los Alamos, and Russian nuclear sites.

Liz Mattson, Outreach Director


Phone: 206-292-2850 x21

Liz Mattson Liz Mattson is the Outreach Director for Hanford Challenge. She brings a refreshing spirit of creativity and reflection to the problems posed by Hanford. Liz has worked closely with Hanford workers to address safety and health problems they are facing, particularly from chemical vapors in the tank farms. She meets with state regulatory agencies and site management to influence their approach to safety issues and their response to injured workers with a goal of having workers’ experience respectfully acknowledged and addressed.

Liz is very active on the Hanford Advisory Board (HAB) where she is the chair of the Public Involvement and Communications Committee, encouraging a more strategic approach to public involvement at Hanford. Liz is also involved on the River and Plateau and Tank Waste Committees of the HAB.

Liz helped launch Inheriting Hanford, a regional Hanford mentorship community, empowering young people to become dynamic participants in Hanford cleanup.

She is a strong advocate of working collaboratively to address the problems posed by Hanford. Dealing with decades of contamination will require an intergenerational, multi-stakeholder approach. By building relationships, encouraging openness and trust and working to understand divergent points of view, the broader community of stakeholders will be better equipped to confront the uncertainties and challenges that face remediation efforts.

Kathryn Sain, Development Director


Phone: 206-292-2850 x27

Kathryn SainKathryn brings years of experience in fundraising, development and donor relations to the organization. Her work with other organizations such as the New York State Trial Lawyers Association and the Boys & Girls Clubs of Atlantic City, as well as the Washington Wildlife and Recreation Coalition, brings a depth of knowledge to Hanford Challenge that will help grow and sustain the organization for future generations.

Kathryn earned her B.A. in Political Science from Stockton University and her J.D. from New York Law School. Originally from New Jersey, she has been enjoying all of the natural splendor the Pacific Northwest has to offer. She looks forward to working with Hanford Challenge to ensure the health and safety of Washington’s citizens and preserving our unique environment. In her spare time, Kathryn enjoys reading and arguing about the feasibility of time travel.

Nikolas Peterson, Staff Attorney


Phone: 206-292-2850 x25

Nikolas PetersonNikolas Peterson returned to Hanford Challenge in 2013 after completing his studies at Seattle University School of Law. Nikolas interned with Hanford Challenge as the 2011 Matthew Henson Environmental Law Fellow where he worked with nuclear whistleblowers. While at Seattle University School of Law, Nikolas also served as the Research & Technical Editor of the Seattle Journal for Social Justice, represented at-risk youth in King County Juvenile Court, and authored an article on Human Trafficking in Washington state.

Nikolas earned his B.A. in History from Walla Walla University (Senior Thesis: U.S. Dept. of Energy & Washingtonians: A Toxic Dose of Mistrust) and his J.D., cum laude, from Seattle University School of Law. Nikolas was born and raised in Walla Walla, WA and feels great responsibility to those who call the Pacific Northwest home to help ensure a safe and effective cleanup of Hanford. In his free time, Nikolas enjoys playing pickup soccer games, gardening, traveling, cooking, and playing bass guitar.

Lori Mitchell, Finance Manager


Phone: 206-292-2850 x25

Lori comes to Hanford Challenge with an extensive background in administrative and bookkeeping support, including work as the Homeowner Liason at Habitat for Humanity in Sarasota, FL.

She enjoys balancing her days off looking at and juggling numbers with quilting. The Pacific Northwest is one of her favorite places to explore and wants to help make Washington a beautiful and safe place or everyone. She has a strong belief in human rights, in particular the right of everyone to live and work in a safe and clean environment.

Emily Bays, Program Assistant


Phone: 206-292-2850

emilyEmily Bays studied Public Health at the University of Washington. In her free time she enjoys hiking and riding her bike around Seattle.




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