By Mary Wisniewski
Feb 13 (Reuters) - Eight collector Corvettes that were swallowed by a sinkhole beneath a Kentucky museum may be stuck in the pit for weeks before General Motors Co can attempt to restore them, officials said on Thursday.
The historic cars, including the millionth Corvette built in 1992, fell up to 30 feet (9 meters) on Wednesday in a scene captured by security cameras at the National Corvette Museum in Bowling Green, Kentucky.
Some of the cars, including a 2009 ZR1 "Blue Devil" that landed on its wheels, seem to be in remarkably good shape, Chevrolet spokesman Monte Doran said in a telephone interview.
Other cars are covered with rubble, making it tough to assess the damage or estimate the cost of repairs, Doran said.
The cars are significant in automotive history and GM wants to restore as many as possible, Mark Reuss, executive vice president of GM Global Product Development, said in a statement.
Before that can happen, the cars must be pulled from the sinkhole that opened in the "Skydome" area of the museum. The museum reopened on Thursday, but the Skydome was blocked off.
It will take two to three weeks to stabilize the area and make sure it is safe, and another four to six days to retrieve the Corvettes, said Mike Murphy of Scott, Murphy & Daniel Construction, which is managing the repairs to the building.
The museum's foundation and structure are in good condition, and after the cars are retrieved, workers will replace the earth and floor system, Murphy said.
Six museum-owned cars were damaged: the white millionth Corvette, a 1962 black Corvette, a 1984 PPG pace car, a 1993 ruby red 40th anniversary Corvette, a 2001 Mallett Hammer Z06 Corvette and a 2009 white 1.5 millionth Corvette.
Two cars on loan from GM were also damaged, the Blue Devil and a 1993 ZR-1 Spyder.
After they are pulled from the pit, the cars will be shipped to a small GM specialty shop in Warren, Michigan, that maintains and restores GM's historic concept cars, GM said.
The millionth Corvette, which was never sold, was likely the most valuable car to fall into the hole and could fetch several million dollars from the right buyer, Corvette historian Jerry Burton has said.
The region of south central Kentucky where the museum is located contains many caves and sinkholes. Mammoth Cave National Park is about 20 miles from Bowling Green.
GM builds Corvettes at a plant near the museum, which opened in 1994. Museum Executive Director Wendell Strode said he is confident it will all be done in time for the museum's 20th anniversary celebration in August.