Ryan was contracted to build an inland underwater testing pond where Navy vessels are subjected to controlled explosions. The work consisted of 1,000,000 cubic yards of dewatered excavation that was contaminated with unexploded ordinance and required armored excavation equipment. Then 600,000cy of glacial till was dredged to depths of 150 below water. Heavy rip rap was placed over the entire top 30 feet of the pond. The dewatered excavation was hauled one mile to a waste site which was subsequently used for the waste dredged material. The dewatered clay materials were excavated by armored draglines, backhoes and articulated trucks. A custom 6,000 horsepower dredge utilizing a heavy 220 feet digger ladder was built on site for the dredging operation.