Originally published in the Eastside Journal, January 5, 2000
Milt Swanson (third from left) talks with officials about the sinkhole that opened at the Red Town Trailhead in Newcastle. Swanson, an 81-year-old former Newcastle mine worker, is consulted often. From left are Glenn Waugh of the Office of Surface Management, Department of Interior; Steve Williams with King County Parks; Swanson; and Jeff Wagner, an engineer with the firm of Hart-Crowser and a consultant to the Office of Surface Management. (Rick Schweinhart/Journal)
Hole probably indicates collapse of old mine
By Jim Larson
An informal summit between federal and county officials was held yesterday afternoon at the edge of a massive sinkhole in Cougar Mountain Park.
Glenn Waugh, from the Department of the Interior, and Craig Larsen, director of the King County Park System, met at the Red Town Trailhead with other officials to evaluate the sinkhole.
“Being this close to a hiking trail, (the sinkhole) is a major concern,” Waugh said.
It’s believed the opening in the earth, roughly 50 feet long and 35 feet wide, was caused by the collapse of an underlying coal mine.
“That’s our assumption, but we don’t know yet,” Larsen said, noting that it might take some time for federal specialists to determine the cause—and recommend solutions.
Yellow warning tape partially surrounds the sinkhole at the Red Town Trailhead in Newcastle. The hole, measuring 35 by 50 feet, is believed to be the latest caused by long-abandoned coal mines collapsing underground. (Rick Schweinhart/Journal)
The Cougar Mountain area was mined for a century, beginning in the 1860s. This isn’t the first time a sinkhole has demanded attention in the vicinity.
“We have one that’s covered with a large metal grate,” said Al Dams, a spokesman for the park system. “Some of them have been covered with cement.”
This latest sinkhole, which the Parks Department first heard about last week, fell about 50 feet. But an opening at the bottom may lead much deeper.
To protect hikers in the popular 3,000-acre park, a chain-link fence has been erected on one side of the hole, and yellow warning tape has been strung around the periphery of the collapsed earth.
Cougar Mountain’s coal mining history
1863 – Coal discovered.
1867 – Lake Washington Coal Co. formed.
1868 – Town of Newcastle is founded.
1870 – Newcastle coal first shipped beyond the Seattle area.
1880 – Immigrant miners and families flood Newcastle. Population rivals Seattle.
1880 – President Rutherford B. Hayes visits Newcastle.
1889 – Labor dispute and violence shut down mines.
1890 – Train journey from Seattle to Newcastle takes three hours.
1894 – Old Coal Creek Mine destroyed by fire.
1901 – Newcastle and Coal Creek have a combined population of 3,000.
1914 – Six-room school built, served by horse-drawn buses.
1917 – Coal production peaks.
1919 – Electricity arrives.
1921 – Striking miners forced out of company-owned homes.
1929 – Newcastle mines close.
1930 – Railroad service ceases.
1932 – Remains of Newcastle buildings sold for scrap.
1937 – Strip mining begins.
1952 – Nike missile batteries installed on Cougar Mountain peak.
1963 – Small-time mining ends.
As they huddled around the back of a pickup truck, officials hung on the words of Milt Swanson, an 81-year-old veteran of the Cougar Mountain mines who lives across the street from the sinkhole.
Swanson, who shared his old maps with the group, has no doubt the collapse was caused by a mineshaft.
“Oh, yes, it shows on the map,” Swanson said. “This mine was dug by the Strain Coal Co. back in the 1940s. There was probably a bulkhead at the end of that old chute. It rotted out.”
Coal mines sprawl through the area, stretching from Cougar Mountain to Newcastle to Issaquah. The mines provided some of the earliest jobs in the area and operated for about 100 years.
In some areas, homes sit on top of mines, and over the years shafts have opened up on the surface. In 1985 the U.S. Office of Surface Mining marked more than 150 openings on Cougar Mountain alone. Some steeply sloping shafts descend 1,250 feet and contain deadly levels of carbon dioxide gas, which is odorless and colorless.
That same year, $700,000 in federal money was budgeted to plug 37 of the most dangerous openings.
The scope of the mining has raised other problems. A hole opened up in a back yard in the Coal Creek area in 1988, and it was reported that that shaft had never been included on mining maps.
Swanson, whose grandfather was killed by falling rock in a nearby mine in 1895, knows the dangers associated with mine shafts.
But with a little common sense, he thinks the trails leading out from the Red Town Trail Head are still safe.
“It’s more dangerous to walk in downtown Seattle than it is up here,” he said.
Watch continues for new sinkholes
Originally published in the Eastside Journal, January 9, 2001
By Elizabeth Williams
NEWCASTLE — No new sinkholes have appeared on the radar screen since last year’s crater appeared on Cougar Mountain, but the county is not about to let its guard down.
This winter, county officials have been busy inspecting Newcastle’s maze of old mine tunnels and shafts. The inspections are performed on a yearly basis, always in the winter. Parks department spokesman Al Dams said the lack of foliage and undergrowth makes it easy to see better—and farther—than at the height of summer.
So far, nothing problematic has turned up, and the county isn’t surprised.
“It’s been pretty dry this year,” Dams said. “It’s not like last year when we had all that rain.”
“It’s weather that helps bring those up, out in the mountains,” he added.
The county uses maps of known mine tunnels and shafts compiled by the U.S. Bureau of Mines. These lists are also used by Newcastle to make sure no one builds their dream home over an abandoned mine tunnel.
These maps were particularly necessary for the planners of the Habitat for Humanity development going up on the Newcastle-Coal Creek Road. An abandoned tunnel runs through the property, and precautions had to be taken to make sure there was no chance of a sinkhole ever swallowing up a building.
Geologists were called in to take core samples and precisely map out the area that would be disturbed if the tunnel collapsed. Planners then made sure the homes were far outside that zone.
“A collapse would not take the structures,” said Mike Nicholson, Newcastle’s director of community development. “It might take the corner of a parking lot.”
The Newcastle Golf Club also was built in the vicinity of a mine tunnel—the Richmond tunnel, which runs from Newcastle to Issaquah. If it were ever to collapse, however, the worst thing that would happen would be the creation of a new course hazard—the builders designed the club so that the only thing in the subsidence, or collapse, zones is mowed grass.
When a sinkhole or open shaft does open up, the federal Department of the Interior is called in to handle the problem. Open shafts usually are plugged up with concrete or blocked with metal grilles. Dams said that because many of the shafts originally were barricaded with wood and dirt, it’s only a matter of time before they rot out and become dangerous.
“There’s always the potential for one to come up somewhere,” he said.
oh, I never actually heard about this. until you posted this… uh oh
LikeLike