Implenia has selected Svensk Kärnbränslehantering (SKB) as the head developer for the US$11 billion Swedish nuclear waste repository spanning 60 kilometers of underground tunnels, longer than the longest line on the New York subway. This engineering marvel will take a decade to complete before it accepts its first shipment of high-level radioactive waste.
Sealing Radioactivity in Advanced Canisters
The Swedish nuclear waste company spearheading the operation will oversee every step of the burial process. Spent nuclear fuel will be encapsulated in specially engineered copper and iron vessels. These canisters are built to last, intended to keep radiation safely contained for up to 100,000 years. Once the fuel is sealed inside, each vessel will be carefully lowered into the bedrock tunnels. Around them, engineers will install bentonite clay, chosen for its unique ability to expand when wet. This natura sealant will form a water-tight and quake-resistant barrier around the canisters.
From Forest Clearing to Bedrock Excavation
The project site is located in Formsark, about 140 kilometers north of Stockholm and will undergo two years of preparatory work. This includes establishing state-of-the-art water treatment systems and clearing large swaths of forest. Once these surface-level operations are in place, the engineers will start drilling deep into the bedrock, descending approximately 1,640 feet underground. At that depth, they’ll carve an intricate network of tunnels designed to house nuclear waste securely.
A Vision Toward the 2080s
Looking ahead, the repository isn’t expected to be fully operational until the 2080’s. Once it is, the facility will hold more than 6,000 canisters of spent nuclear fuel. Though the timeline stretches far into the future, every step is deliberately planned to ensure safety and sustainability. Transitioning from the preparation of the site to the final sealing of the last canister, this massive undertaking reflects Sweden’s long-terms commitment to responsible nuclear waste management, an essential chapter in the story of global energy and environmental protection.
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SKB Swedish Nuclear Repository Overview
Project name: Final Spent Nuclear Fuel Repository
Location: Söderviken, near Forsmark Nuclear Power Plant in Östhammar Municipality, 150 km north of Stockholm
Project developer: Svensk Kärnbränslehantering AB (SKB)
Budget & Funding
Estimated cost: 11 billion USD
Fully funded by Swedish nuclear power operators
Timeline
Groundbreaking: January 15, 2025
Surface preparation: 2025–2027
Tunnel excavation begins post‑2027
Repository ready for first waste: late 2030s
Full extension and sealing: by 2080s
Engineering Highlights
Depth: 500 m (1,640 ft) in 1.9 billion‑year‑old bedrock
Tunnel network: over 60 km underground
Surface footprint: 24 ha
Excavation volume: 2.7 million m³ of rock
Waste Capacity & Containers
Capacity: 12,000 tonnes of spent nuclear fuel
Number of canisters: approx. 6,000
KBS‑3 method: copper‑iron capsules sealed in bentonite clay
Designed lifespan: containment for 100,000 years
Regulatory & Safety Framework
Licence granted by Land & Environment Court (2021–2024)
Safety reviews by Swedish Radiation Safety Authority required
Environmental conditions include groundwater protection, noise control, and biodiversity measures
Independent NGO raised concerns about copper corrosion; ongoing safety studies
Monitoring & Long‑Term Stewardship
Repository to remain sealed and unmanned once full by late 21st century
Key Information File (KIF) created to pass knowledge across generations
Geological mapping and performance monitoring will continue throughout operational phase
