Geological Investigation

On December 3, torrential rains and an inadequate stormwater system combined to undermine the pavement on a portion of Bethel Avenue and an adjacent parking lot. The result was a sinkhole about 50 feet long, 20 feet wide and 30 feet deep. Fortunately, no one was injured when the hole opened. -Kitsap Sun online editorial

GPR Data LLC was called in to investigate this sinkhole in December 2007, but what we discovered was not what anyone expected. The sinkhole had been completely attributed to raw volume of water traveling through a drainage pipe. However, upon investigation with ground penetrating radar, we determined that three underground storage tanks had been buried and forgotten, in close poximity to the sinkhole. At least one of the tank walls had been destroyed by electrolysis, creating an open void which allowed sub-surface evacuation of the subgrade structure.

GPR investigation discovered additional contributing factors to this incident, helping to resolve the existing situation and prevent future occurances which otherwise would have been overlooked.

GPR Data LLC | Phone: 541-345-1075 | Fax: 541-683-6324