thedrifter
07-07-05, 05:55 PM
Pressure washing to preserve presidents' granite complexion
DIRK LAMMERS
osted on Thu, Jul. 07, 2005
Associated Press
MOUNT RUSHMORE NATIONAL MEMORIAL, S.D. - Neglect washing your face for 65 years and you're likely to start seeing the effects - dirt, grime, lichen microbes.
In an extreme makeover of monumental proportions, a team of rappelling pressure washers planned to start giving the four presidents atop Mount Rushmore National Memorial their first-ever facials.
Thorsten Mowes, a technician with the German company leading the project, started the work shortly after 2 p.m. Thursday, hitting the left side of Thomas Jefferson's forehead with a stream of pressurized water.
He also gave Jefferson's eyelid and jaw a quick blast during Thursday's test run.
"The roots of the lichens are digging into the stone," said Mowes, who scaled Washington's face in April and found that dirt, grime and lichens had invaded.
When the project kicks into high gear Friday or Saturday, five workers - all holding water guns - will repel down the faces at the same time. The work could take four or five weeks.
Visitors to Mount Rushmore may see workers rappelling off the faces during that time, said Judy Olson, Mount Rushmore's chief of interpretation. It will give tourists an idea of how large the mountain is, she said.
The washings are compliments of Alfred Karcher GmbH & Co. KG, a German manufacturer of cleaning machines that has donated 80 such "restoration cleaning projects" from Berlin to Beijing, said Karcher spokesman Frank Schad.
Olson said Karcher has impressive credentials, and the Winnenden, Germany-based firm's offer was a pleasant surprise.
"As a federal agency, we don't have a lot of money in our budget to be pressure washing faces," Olson said. "When they said they would do it for free, that's when we started considering having this done."
Schad said the company pressure-washed the base of the Statue of Liberty two years ago and was looking for another interesting project to do in the United States. Karcher is teaming up with a German "rope access company" to gain access to the faces, Schad said.
"This is a first time for us," he said. "Normally we work on scaffoldings. It's easier."
The water used to clean Mount Rushmore starts its path at the bottom of the mountain in a Keystone Fire Department tanker. It is pumped up to the heads of Jefferson, Washington, Theodore Roosevelt and Lincoln through a hose that dangles to the left of Washington's face.
The water fills a 12-by-12 foot yellow pool sitting just outside the Hall of Records and is pumped to five commercial-grade pressure washers sitting just behind Washington's skull.
The company has not yet figured out how much the project will cost, said Schad.
Six National Park Service rangers from Mount Rushmore and a volunteer from the nearby Crazy Horse Memorial are working with the Karcher company.
One of the rangers, Blaine Kortemeyer, had three weeks of rope training recently. He had done some rappelling when he was in the Marines.
"I've been wanting to go out on the faces for a long time now since I got here," said Kortemeyer, who has spent five of his 15 years as a ranger at Mount Rushmore.
The main purpose of the work is preservation, not aesthetics, Duane Bubac, Mount Rushmore facilities manager, said Thursday.
"I don't think the average visitor will be able to tell the difference" after the power washing, he said. "It's mainly a stabilization and preservation activity."
Sculptor Gutzon Borglum carved Mount Rushmore in 21 blocks of granite that contained many preexisting cracks. Lichens can work themselves into crevices and cause "bio-corrosion," producing an acid that can damage the faces' granite complexion.
Borglum's maintenance plan called for filling the cracks with a mixture of white lead, linseed oil and granite dust. In 1991, the monument switched to a newer silicone sealant, and Park Service workers dangle from harnesses each year to inspect and fill the cracks.
"Those cracks were always there," Olson said. "It's just the mountain was in several rock blocks of granite. It wasn't a solid piece."
Schad said the mountain is stable but that workers will take special care near the cracks, which are more porous than the granite. They'll also use no chemicals, opting instead for pressurized 212-degree water.
Pressure washing is the perfect method for historical structures, Schad said, as it offers an incredible amount of flexibility. Workers can adjust the pressure in the pump, water flow, temperature, spray angle and spray distance, as well as their own muscle movement, to get the effect they need.
"So you can react very, very quickly on differences," he said. "So the cracks will be treated more smoothly than the rest."
Ellie
DIRK LAMMERS
osted on Thu, Jul. 07, 2005
Associated Press
MOUNT RUSHMORE NATIONAL MEMORIAL, S.D. - Neglect washing your face for 65 years and you're likely to start seeing the effects - dirt, grime, lichen microbes.
In an extreme makeover of monumental proportions, a team of rappelling pressure washers planned to start giving the four presidents atop Mount Rushmore National Memorial their first-ever facials.
Thorsten Mowes, a technician with the German company leading the project, started the work shortly after 2 p.m. Thursday, hitting the left side of Thomas Jefferson's forehead with a stream of pressurized water.
He also gave Jefferson's eyelid and jaw a quick blast during Thursday's test run.
"The roots of the lichens are digging into the stone," said Mowes, who scaled Washington's face in April and found that dirt, grime and lichens had invaded.
When the project kicks into high gear Friday or Saturday, five workers - all holding water guns - will repel down the faces at the same time. The work could take four or five weeks.
Visitors to Mount Rushmore may see workers rappelling off the faces during that time, said Judy Olson, Mount Rushmore's chief of interpretation. It will give tourists an idea of how large the mountain is, she said.
The washings are compliments of Alfred Karcher GmbH & Co. KG, a German manufacturer of cleaning machines that has donated 80 such "restoration cleaning projects" from Berlin to Beijing, said Karcher spokesman Frank Schad.
Olson said Karcher has impressive credentials, and the Winnenden, Germany-based firm's offer was a pleasant surprise.
"As a federal agency, we don't have a lot of money in our budget to be pressure washing faces," Olson said. "When they said they would do it for free, that's when we started considering having this done."
Schad said the company pressure-washed the base of the Statue of Liberty two years ago and was looking for another interesting project to do in the United States. Karcher is teaming up with a German "rope access company" to gain access to the faces, Schad said.
"This is a first time for us," he said. "Normally we work on scaffoldings. It's easier."
The water used to clean Mount Rushmore starts its path at the bottom of the mountain in a Keystone Fire Department tanker. It is pumped up to the heads of Jefferson, Washington, Theodore Roosevelt and Lincoln through a hose that dangles to the left of Washington's face.
The water fills a 12-by-12 foot yellow pool sitting just outside the Hall of Records and is pumped to five commercial-grade pressure washers sitting just behind Washington's skull.
The company has not yet figured out how much the project will cost, said Schad.
Six National Park Service rangers from Mount Rushmore and a volunteer from the nearby Crazy Horse Memorial are working with the Karcher company.
One of the rangers, Blaine Kortemeyer, had three weeks of rope training recently. He had done some rappelling when he was in the Marines.
"I've been wanting to go out on the faces for a long time now since I got here," said Kortemeyer, who has spent five of his 15 years as a ranger at Mount Rushmore.
The main purpose of the work is preservation, not aesthetics, Duane Bubac, Mount Rushmore facilities manager, said Thursday.
"I don't think the average visitor will be able to tell the difference" after the power washing, he said. "It's mainly a stabilization and preservation activity."
Sculptor Gutzon Borglum carved Mount Rushmore in 21 blocks of granite that contained many preexisting cracks. Lichens can work themselves into crevices and cause "bio-corrosion," producing an acid that can damage the faces' granite complexion.
Borglum's maintenance plan called for filling the cracks with a mixture of white lead, linseed oil and granite dust. In 1991, the monument switched to a newer silicone sealant, and Park Service workers dangle from harnesses each year to inspect and fill the cracks.
"Those cracks were always there," Olson said. "It's just the mountain was in several rock blocks of granite. It wasn't a solid piece."
Schad said the mountain is stable but that workers will take special care near the cracks, which are more porous than the granite. They'll also use no chemicals, opting instead for pressurized 212-degree water.
Pressure washing is the perfect method for historical structures, Schad said, as it offers an incredible amount of flexibility. Workers can adjust the pressure in the pump, water flow, temperature, spray angle and spray distance, as well as their own muscle movement, to get the effect they need.
"So you can react very, very quickly on differences," he said. "So the cracks will be treated more smoothly than the rest."
Ellie