The Rocky Mountain
Project refers to a pumped-storage
generating plant. Water is stored in a 220 acre reservoir
atop "The Rocky Mountain" in Georgia. During
peak demands, water is released from the upper reservoir
through a 570 ft shaft and a 1,935 ft tunnel via turbines
into a 600 acre main lower reservoir. At night the water
is pumped back to the upper reservoir using excess power
generated at coal and nuclear power plants. Two auxiliary
reservoirs covering 605 acres supply make up water.
The Judy Company, Inc. was awarded a $3.1 million
subcontract from Power Plant Constructors, a Morrison
Knudson-Clements joint venture. The scope of the work
included drilling and grouting the foundations of seven
dams, including the upper reservoir with a length of
12,788 ft. Also included in the contract were rock
anchors, exploratory coring and drainage holes. The work
took nearly 3 years to complete.
SOLUTION
Access to many of
the work areas was difficult. The main dam had a sixty
foot nearly vertical abutment. An 8'x6' gallery in the
main dam included a grout curtain and drainage holes. A
total 9,000' of drain holes were drilled underground from
a drainage adit located above the penstocks. Piezometers
were also drilled on-site.
Special grouting equipment was designed and built for
the project because of the large volumes of cement
anticipated. Because the project covered more than 5,000
acres, mobility was an important ingredient of successful
completion.
