About the Seaway Site
Location
The site is located along River Road in Tonawanda, NY, within the 100-acre Seaway Industrial Park, near the Grand Island Bridge.
Background
- During the 1940s, waste from the former Linde Site's nuclear weapons program activities were stored at a property known as the Ashland 1 site (adjacent to the Seaway Site).
- In 1974, some of those materials were moved from the Ashland 1 Site and disposed of in the Seaway Site.
- In 1993, disposal to the Seaway landfill ended and a portion of the landfill was capped per state requirements.
Areas A, B, and C:
The FUSRAP-contaminated material in areas A, B, and C have been covered with an engineered cap that measures about 22-acres in size and about 5-feet thick. This engineered cap is designed to safely contain the FUSRAP-contaminated material and consists of the following layers:
- Radon attenuation layer: This is placed first and directly on top of the landfill waste. It is composed of soil with specific moisture and compaction properties to limit radon movement through the engineered cap.
- Gas venting layer: A permeable layer designed to conduct landfill gas to passive surface vents.
- Barrier layer: A geosynthetic clay liner and geomembrane designed to limit surface water infiltration to the waste below.
- Subsurface drainage layer: A geocomposite layer designed to safely conduct surface water that infiltrates the fill later to drainage outlets.
- Select fill layer: Clean imported fill designed to prevent damage to the barrier layer.
- Topsoil layer: Used to promote vegetative growth and prevent erosion of the engineered cap.
Areas not included in the remedial design
Seaway Area D: Remediated under the Record of Decision for the adjacent Ashland site in 2000.
Seaway Northside: Remediated in 2015.
Seaway Southside: Remedial action not yet completed. USACE is reviewing data to support the planning and design of potential future remediation.
Community Involvement & Project Status
Community Engagement
U.S. Army Corps of Engineers (USACE) engaged with the community in March and April 2024, including a public information session on April 18, 2024.
Contract and Scope
In September 2023, USACE awarded a $17.6 million contract to install a 22-acre engineered cap over Areas A, B, and C of the Seaway Site.
Site Preparation and Safety
By late April 2024, equipment staging, site preparation, and safety measures (including air monitoring) were completed. Air monitoring began 30 days before remedial work and continued through the completion of the radon attenuation layer in August 2024.
Construction
Construction of the engineered cap began on April 30, 2024, and was completed in December 2025.
Seaway Site Timeline
| Year |
Event |
| 1974–1997 |
Atomic Energy Commission (AEC)/U.S. Department of Energy (DOE) managed FUSRAP; surveys and investigations conducted at Tonawanda properties, including Seaway. |
| 1993 |
DOE completed a Remedial Investigation (RI) and Feasibility Study (FS) and issued a Proposed Plan (PP) for on-site disposal of contaminants. |
| 1994 |
DOE suspended decision-making to re-evaluate alternatives due to community concerns. |
| 1998 |
FUSRAP responsibility transferred from DOE to USACE under the Fiscal Year 1998 Energy and Water Development Appropriations Act (Pub. L. 105-62); separate plans and decisions issued for other Tonawanda sites. |
| 2008 |
USACE issued a Feasibility Study addendum and revised Proposed Plan, identifying contaminated soils and confirming groundwater/leachate were not impacted. |
| 2009 |
Record of Decision (ROD) approved; selected remedy was containment with limited off-site disposal, including capping and excavation. |
| 2016 |
USACE completed excavation and off-site disposal of contaminated soil from Seaway Northside. |
| 2017 |
USACE delineated contamination in Seaway Southside. |
| 2021 |
Contract awarded for engineered cap design and planning. |
| 2022 |
First five-year review of the selected remedy completed in accordance with Comprehensive Environmental Response Compensation and Liability Act (CERCLA) requirements. |
| 2023 |
Contract awarded for engineered cap installation. |
| 2024 |
Installation of the engineered cap began. |
| 2025 |
Engineered cap completed in December 2025. |
Key Documents
Key documents are available at the Project Assistance Library (PAL).
Sources of Additional Information
News from the Corps
Subscribe to periodic updates by emailing fusrap@usace.army.mil.
Contact Information
Phone: 1-800-833-6390 (Option 4)
Email: fusrap@usace.army.mil
Address:
U.S. Army Corps of Engineers, Buffalo District
478 Main Street
Buffalo, NY 14202