Project: Nikaitchuq
Location: Alaska
Client: Sandwell Engineering Inc. / ENI Petroleum

The expansion for the Nikaitchuq oil production was approved by the Alaska Department of Natural Resources Division of Oil and Gas in 2007.  The expansion consists of several major interconnected developments including an offshore drill site and onshore developments.  The drill site was to be established on a gravel-fill island, namely Spy Island.  The onshore developments include an expansion for the processing facility at Oliktok Point and the Nikaitchuq Operations Center.  The challenge of this project was to perform complex engineering analyses for frozen ground conditions.

M+EG was contracted by Sandwell Engineering Inc. to provide geotechnical input for the project.

M+EG was responsible for the following activities:
  • Evaluate the settlements at the drill site for the proposed gravel placement sequence.
  • Thaw settlement assessment for different thaw depths and temperatures at the processing facility.
  • Spread footing design for both the drill site (unfrozen ground) and the processing facility (frozen ground).
  • Baffle plate design for end-bearing pile.
  • Pile capacity in frozen ground with the consideration of using adfreeze for frozen conditions and using grout for locations where significant thawing is expected.
  • Downdrag on piles resulting from thaw settlements.
  • Evaluate the load-deflection characteristics for pipe and piles installed in frozen ground.
  • Foundation design for the sealift modules at Oliktok Point using the results from Multi-Channel Analysis of Surface Waves (MASW) testing.
  • Provide analyses and input for the piles to be used in the structural design for both the drill site and the processing facility.
Project Highlights:
  • Estimate the characteristics of frozen soils to be used for engineering purposes, taking into account the sensitivity to climate change and creeping in frozen soils.
  • Since the site location is extremely remote, the limitation related to construction methods and available materials was critical in the design process.
  • With the global climate changes, the thaw depth was expected to increase annually resulting in significant downdrag on the pile foundation and thaw settlements.  Analyses were carried out to evaluate the sensitivity of different thaw depths and to estimate the potential differential settlements across the site.