Protecting Human Health and the Environment

About the Kerr-McGee Chemical Corp – Soda Springs Plant Superfund Site

The Kerr-McGee Chemical Corp – Soda Springs Plant Superfund Site (the Site) was contaminated by nearly 40 years of vanadium production operations.

In 1989, the contamination in groundwater led the U.S. Environmental Protection Agency (EPA) to add the Superfund site to the National Priorities List (NPL) of federal Superfund sites. The NPL is the EPA list of the worst hazardous waste sites.

The Superfund designation means the remediation must follow the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) process that EPA uses to clean up Superfund sites. CERCLA is also known as Superfund.

The Multistate Environmental Response Trust (Multistate Trust) is performing investigations and remediation of the Site under EPA oversight and in consultation with the Idaho Department of Environmental Quality (IDEQ).

Milestones Achieved to Date

In 2011, the Multistate Trust accepted responsibility for owning and managing the Site in Soda Springs as part of the Tronox bankruptcy settlement.

Since assuming responsibility for the Site as a court-appointed trustee, the Multistate Trust has implemented a number of environmental actions, environmental investigations, and other activities, including the following:

• Completion of the Domestic Well Survey and Water Quality Sampling, 2015

• Completion of the Waste Removal and Initial Site Cleanup, 2016

• Completion of the 10-Acre Pond Time-Critical Removal Action, 2018

• Completion of Building Demolition, Waste Excavation, Site Regrading, and Repository Construction, 2019

  • Volume 1 – Text and Appendices A and B

  • Volume 2 – Appendices C, D, E, F, G, H, and I

  • Volume 3 – Appendices J and K

  • Volume 4 – Appendices L, M, N, O, P, Q, and R

• Completion of the Supplemental Remedial Investigation, 2020

  • Volume 1a – Text

  • Volume 1b – Tables

  • Volume 1c – Figures

  • Volume 2 – Appendices A, B, and C

  • Volume 3 – Appendix D

  • Volume 4 – Appendices E, F, G, H, I, and J

  • Volume 5 – Appendix K

  • Volume 6 – Appendices L, M, N, O, P, and Q

• Completion of the Human Health Risk Assessment (HHRA), 2020

  • Volume 1

  • Volume 2

• Completion of the Screening Level Ecological Risk Assessment, 2020

• Completion of the Focused Feasibility Study, 2022

• Completion of the Proposed Plan, 2023

• Supporting EPA issuance of the Record of Decision (ROD) Amendment, 2023

More Documents

• Administrative records published by EPA for the Site: EPA Administrative Records

• EPA website for this Site: www.epa.gov/superfund/kerr-mcgee-soda-springs.

• Visit the Soda Springs Public Library at 149 S. Main Street, Soda Springs, ID 83276. Request the “Kerr-McGee Chemical Corp. – Soda Springs Plant Superfund Site Information Repository.” The Site documents are available for viewing on a USB drive. For information about the library, visit https://soda.lili.org.

Current Activities and Work

In March 2023, based on the alternatives evaluated in the Focused Feasibility Study (FFS) Report, EPA issued a Proposed Plan for changes to the Site cleanup approach. A public meeting and comment period took place after the Proposed Plan was issued. In November 2023, EPA issued a Record of Decision (ROD) Amendment to select the revised remedy for the Site.

Concurrently, a Treatability Pilot Test is being designed and initiated to evaluate pre-design criteria that will be used in the design and implementation of the revised remedy..

Our Beneficiaries and Regulatory Agencies

In Soda Springs, the Multistate Trust is working in collaboration with its federal and state governmental beneficiaries for the Site:

• the United States, which is represented by EPA and the U.S Department of Justice (DOJ); and

• the State of Idaho, which is represented by IDEQ.

EPA is also the lead regulatory agency for the Site, and IDEQ is the non-lead agency.

In EPA’s role as lead agency, EPA approves Site-specific remediation plans and activities and the hiring of contractors to perform environmental activities at the Site. In its role as beneficiary, EPA approves the Multistate Trust’s work plans and annual environmental budgets, in consultation with IDEQ.

The sale, transfer, or disposition of any portion of the ±547-acre Multistate Trust property must be approved by EPA, in consultation with DOJ, and IDEQ.

Our Commitment to Community Stakeholders

The Multistate Trust and its beneficiaries recognize that the City of Soda Springs and residents near the Site have been impacted by the Site.

The Multistate Trust team remains dedicated to protecting and engaging our neighbors and the surrounding community as we remediate the Site and plan for its safe, beneficial reuse for future generations.

Learn more about our stakeholder engagement efforts at Community and Reuse.