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PETROLEUM DIRECTORY: Keeping the frozen lands frozen Arctic Foundations specializes in frozen barriers and frozen soils technology Susan Braund Petroleum Directory Contributing Writer
The frozen North may have met its match in Erv Long, principal owner of Arctic Foundations, Inc. His 50-plus years of northern engineering and the instinctive wizardry that comes with understanding both the land and weather cycles, puts Long right up there in the category of Permafrost King, or at least the guy who is up to the challenge of developing frozen lands building technology.
“As man has widened his horizons and encroached on these frozen areas throughout the arctic and sub-arctic regions of the world,” says Long, “one of the major engineering and construction obstacles has been the permafrost. Our frozen lands have become more and more of a design challenge to planners, engineers, and contractors alike.” Permafrost Understanding permafrost is not only important to civil engineering and architecture, it’s also a crucial part of studying global change and protecting the environment in cold regions, according to the IRC Institute for Research in Construction. Permafrost is soil that remains frozen throughout the year. It occurs as large continuous areas of frozen soil, or in scattered patches surrounded by soil that experiences normal freeze-thaw cycles, or discontinuous permafrost. In all cases, an active layer of soil that experiences normal freezing and thawing during the seasons overlies permafrost.
“Permafrost soils must be kept frozen for the soil not to lose its bearing capacity,” cautions Frostline Northern and Remote Technology in Housing. “When soil has relatively high water content in the active layer, measures must be taken to keep it frozen. When soil contains massive ice deposits, extra care must be taken in the design of the foundation if this is the case … Buildings transmit heat to the underlying soil through convection and radiation. This can thaw frozen soil, leading to displacement of the foundation.” The company Arctic Foundations Inc. has more than 50 years experience as an innovator in foundation construction and technology for frozen soils and frozen barriers. Long started the business in the early 1970s while still working at the Corps of Engineers. He recognized the advantage of freezing previously thawed unstable ground and the need to maintain permafrost; in the late 1950s he developed the Thermopile system and went on to patent his thermal transfer process.
Initially he did his design work at night and hired others to operate the business, and then in 1976 he retired from the Corps and took over active management. Because manufacturing costs were high in Alaska during pipeline construction years, Arctic Foundations contracted its manufacturing in Seattle from 1972-78. In the early 1980s the company bought its Anchorage facility and eventually added adjacent property. The complex is now comprised of 12,500 square feet of building space and 53,000 square feet of yard space, including a metal spray and fusion plastic coatings shop and a pressure vessel shop, one of few in Alaska. Arctic Foundations employs a core six people and seasonally expands up to 17, depending on contracts. “Welding is the key to our quality. We have several excellent permanent, full time welders,” says Long.
“The Corps installed the first commercial units in 1960 at the Aurora and Glennallen communication sites,” says Long, “and they are still functioning and maintaining their permafrost stability today. Since that time we’ve designed, manufactured and installed thousands of ground freezing and thawing systems and units throughout North America, Canada, Greenland, and Russia.
“We’ve become a leader in state-of-the-art permafrost foundations, ground stabilization pressure vessels, Thermopiles and Thermoprobes and frozen barriers and we continue to develop and advance Thermosyphon technology as techniques improve in related sectors of the geotechnical industry.” The technology Arctic Foundation’s primary product is the Thermosyphon, or pressure vessels with aluminum and fusion coat epoxy finish, also called Thermoprobes. The Thermosyphon is strictly a heat-transfer device, basically a closed evaporation condensation system, extracting excess heat out of the earth, when used to maintain frozen conditions.
“Let’s go from the top down,” explains Long. “Air colder than the ground causes condensation on the inside of the top of Thermosyphon that reduces pressure in it. That reduction then permits boiling of the liquid below ground which causes reduction in temperature and permits heat to transfer from soil to the Thermosyphon.”
The technology was used in the vertical support members on the trans-Alaska pipeline and to stabilize the foundation of the terminals on each end of the Colville River crossing for the Alpine project, along with hundreds of other projects.
Thermosyphon barrier freezing technology compares favorably to many of the non-freezing technologies to depths of 50 feet — and is unbeatable at greater depths for project durations of five years or longer, according to the company, including microbial barriers, sheet piling, slurry walls, grout injection, pump-treat-inject, in situ vitrification and membrane barriers.
• Temperature of the barrier can be controlled to ensure the necessary liquid-solid phase change.
• Frozen barriers can be developed in soils that are saturated or relatively dry.
• Can be applied at any depth from the ground surface, or its application can be restricted and applied only to a predetermined zone below the surface.
• Can be used to form a vertical, horizontal, or angled impervious barrier, or as an encapsulating soil mass.
• Excavation is minimized as Thermoprobes are installed by drilling or driving.
• A system can be installed quickly if necessary.
• Regulatory Issues are typically non-controversial due to minimal environmental impact.
• Active-passive hybrid systems are used in climates where low winter temperatures do not prevail or where freezing is required prior to the onset of cold weather. Foundations According to Long, thermo design of a foundation to maintain permafrost must extract heat from building of seasonal thaw from above, geothermal heat from below, warmer soils surrounding the site, buried water and sewer lines, runoff from building roofs, and surface drainage. Design must also allow for seasonal thaw without affecting the total foundation area.
“For foundations, our clients are the engineers. We build to their specs,” says Long. Containment and frozen barriers Confinement of a buried hazardous waste can be accomplished by directly freezing a contaminated soil mass or by surrounding it with a frozen barrier.
“AFI’s Hybrid Thermosyphon Technology is a well-established technology that is ideally suited to the long-term containment and immobilization of many subsurface hazardous wastes that the US Department of Energy has targeted as part of their environmental management program,” Arctic Foundations told Petroleum News. “These contaminants include tritium, strontium 90, DNAPLs, and many others. Few technologies can match ours.”
The most recent and pertinent application of contaminant control was a demonstration project at the Oak Ridge National Laboratory, in which the HRE Reactor Pond was surrounded with a frozen barrier measuring 300 feet long, 12 feet wide, and 30 feet deep. Installed during the summer of 1997, the system continues to operate, functioning as planned. It is effectively stopping the flow of radionuclide contaminants from the pond and is doing so in a very cost effective, trouble-free manner. Mining and dams Ground freezing can be a beneficial technology for dam building without regard to any specific industry, or the purpose the dam serves. A frozen dam can be even more effective than a traditional type because freezing can more effectively seal multiple soils types in the dam and, if necessary, well below it, as evidenced at the Panda Dam and Ekati Diamond Mine in Canada’s Northwest Territory, and a tailings dam in the Russian Far East. Long is currently discussing business with Arctic Foundations of Canada and Canadian mining groups. The technology he uses for mining and dams is the same as that employed for permafrost foundations or frozen barriers.
Arctic Foundations serves clients in multiple industries, including oil and gas, mining, state and federal governments and individual business — anyone who needs to maintain frozen ground over long periods of time or who requires a frozen barrier or foundation.
Editor’s note: Susan Braund owns Firestar Media Services in Anchorage, Alaska.
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