Sunday, March 1, 2015

Explosion at Equality

On Sunday, April 6, 1913, the swollen Ohio River backed more than 20 miles up Illinois’s Saline River, flooding a coal mine that residents of Equality were desperately trying to save—exploding the mine

At an ominous low underground rumbling that feels like an earthquake, someone yells: “Get back—run for your lives!”


With a roar almost beyond comprehension, a mighty geyser erupts from the main shaft of the Equality coal mine, the filthy floodwater propelling concrete blocks, narrow-gauge railroad mine cars, wheels, engines, and cages higher 
Second geyser erupting from the Equality coal mine was less than a third as high as the first. Credit: Coal Age, May 10, 1913, page 728
than 500 feet into the air. Men scatter at a dead run, desperate to avoid the tonnage of water, stone, dirt, and machinery raining down as far as a hundred yards away from the mine, crashing to the ground with enough force to bury themselves.

Twenty-two minutes after the outburst, a second geyser shoots 150 feet into the air. 

Eight minutes later a third geyser erupts, perhaps 75 feet high. Numerous others follow, each lower than the preceding one, until about 5 PM when the eruptions reduce to a succession of huge air bubbles loudly issuing from the nearly filled mine shaft. 

The angry bubbling persists more than a week until the destroyed mine completely fills with water lying quietly and glistening with an oily sheen, looking like a caved-in well about 40 feet across.  

What happened? And how could the devastating Great Easter 1913 flood trigger a mine explosion?

Mining coal in Illinois
Coal mining District 5 is
at the bottom right
Lying under more than 60 percent of area of the state of Illinois are vast fields of coal. In 1913, Illinois was third only to Pennsylvania and West Virginia in the nation’s coal production, the state providing 4 percent of the world’s supply. The coal industry, which employed 80,000 men, was among the most important industries in Illinois. Although fewer than 30 coal mines are being worked in Illinois today, some 7,400 operated in the past.

The mining town of Equality lay on the north bank of the Saline River, about 20 miles west of the Ohio River, on the Louisville and Nashville Railroad line. In 1913, the Equality coal mine—which changed names five times through a succession of 10 owners between when its shaft was sunk in 1882 and its closure in 1930—was owned by the Gallatin Coal and Coke Company. It was one of the older and smaller mines in state District V in the very southern and eastern part of the state, which encompassed Seam 5 through Gallatin and Saline Counties. 

The vertical mine shaft opening was on the western edge of town, about
Ohio River is at the right, Equality is in the middle, and
Harrisburg is at the far left; map is about 30 miles across
1,000 feet from the Saline River. It was on the top of a rise, with its air shaft opening in ground 13 feet lower to the west. So far, its elevation had saved the main shaft from flooding—just barely in the case of the major 1884 flood just two years after the shaft was sunk, when floodwaters approached to within just a foot of the opening. But even a near miss was a relief: the 1884 flood was the greatest ever experienced in Illinois memory, and it was widely felt that a greater flood was unlikely.

Headwater and backwater
But then the skies opened across the Midwest on Easter Sunday, March 23, 1913. Sheets of rain kept falling and falling through that week. Equality—and the rest of Illinois—received only about half the 10+ inches of maximum rainfall experienced by Ohio and Indiana in those four or five days (Harrisburg about five miles west of Equality recorded an unofficial total of 6 inches). Even so, five or six inches of rainfall in less than a week is a very sodden week. 

Modern plotting of precipitation causing the Great Easter 1913 flood reveals that Harrisburg's unofficial measurement of 6 inches of rain was accurate.
Beginning Easter Monday, the Saline River rapidly rose from runoff from all over southern Illinois, peaking midweek about 15 feet above normal. Then it started falling as the excessive rainfall and runoff discharged downstream, toward the Ohio River 20 miles east.

But the Ohio River itself was swelling from torrential floodwaters pouring into it from tributaries in Pennsylvania, Ohio, Indiana, and Kentucky. The biggest was the Wabash, whose source at the western edge of Ohio was right in the band of maximum intense rainfall. Worse, the mighty Wabash—augmented by runoff from across much of Indiana—joined the swollen Ohio River just north of the Illinois river community of Shawneetown, about 20 miles east of Equality.

As the flooded Ohio River grew deeper and wider, it stopped the drainage of 
the Saline River. Worse, the mixed waters of the two rivers began backing up the Saline River. The Saline River’s fall stopped and began rising again, virtually as fast as it had risen a few days earlier, only this time showing no signs of stopping at its previous peak. The water kept getting higher and wider.

By the end of March, it was clear to the Equality mine owners, workers, and town residents alike that the old 1884 flood record was on its way to be broken. And if the mine were flooded, many men living in Equality would be thrown out of work for months, unable to provide for their families.

A large crew of men hastily began building a massive makeshift levee surrounding the mine opening. For  75 feet on each of four sides (a total of 300 feet), they trenched the topsoil down to the dense clay packed the trench with moist clay, tamping it well to form a dense barrier that they hoped would be impervious to erosive undercurrents. On either side of that filled-in trench, they built two heavy timber retaining walls six feet apart, filling the gap between them with well-tamped moist clay.

Collapse and explode
By April 1, the mine was surrounded by flood backwater, which just kept rising. It hampered the levee construction because all supplies now had to be boated a few hundred feet to the workers. By April 2, part of the wooden cribbing that reinforced the vertical walls in the mine shaft gave way on the east side of the shaft about 20 feet below the opening, letting in a flood of water and carrying away part of the levee. The miners, now helped by every able-bodied boy and man from Equality, stopped the break. 

But the next day, old and weakened cribbing on the west side of the shaft also gave way even more disastrously, taking a different part of the levee into the shaft. Some of the surface also caved in, opening the shaft 10 or 12 feet wider. Again, without missing a beat, all the men redoubled their efforts and shored up that breach as well. 

By now the floodwaters were a good five feet higher than the 1884 record at 
Flooding of the Saline River at Harrisburg, 5-10 miles west
upstream of Equality, just off the map at lower right.
Credit: Coal Age, May 1913
the mouth of the mine. The town of Equality was inundated, too, with some 300 residents driven from their homes and doubling up with friends and neighbors. But dealing with the flooding in town fell to the wives and children. For the next two days, the men—desperate to save their families’ livelihoods—kept piling sandbags atop the levee, daring finally to admit a hope that maybe, just maybe, by dint of extraordinary effort, it might be possible to keep the levee higher than the still-rising backwater. 

Then, on Sunday morning, April 6, someone noticed a very small stream rushing in from the south side of the levee at a point about 10 feet below the surface of the water. Despite all efforts to stop the leak with sandbags, the stream grew ever larger. As extensive caving was also discovered near the powerhouse 50 feet away, the danger was clear. Everyone was ordered away from the buildings.

At 9:28 AM, the levee collapsed with a mighty inrush. The velocity of the river water into the mine shaft was so great it swept mine cars, barrels of oil, concrete piers, and tons of rubbish ahead of it from hundreds of yards around—the suction pulling out the end of the engine and boiler room and blacksmith shop. Although the vertical hoisting shaft was filled in an hour and 22 minutes, for the next five hours water continued to flood into all the mine’s underground rooms about 50 feet below. 

Also trapped was all the air that had been in the mine, and which had been 
Equality coal mine is large yellow area near center; main
shaft is at lower right closest to Saline River; air shaft is
a bit left (west of it). Harrisburg is off map to left.
(Name of mine is the last one given by its last owner)
Credit: Illinois State Geological Survey
unable to escape through the flooded air shaft. As more water poured in, the air was compressed under ever increasing water weight and pressure.

At about 3:25 PM, the mine seemed almost quiet, and was surrounded by sightseers standing on the gob pile (waste rock from digging the mine) or other higher ground gawking at the destruction.
Then, according to the 1913 Annual Coal Report of Illinois, at 3:50 PM, with what sounded like a tremendous explosion, 

…the air [compressed] rebounded with a force that was almost beyond comprehension. It threw out mine cars, cages, huge concrete blocks, sheave wheels, engines, and completely destroyed the entire top works. Water, stone, dirt, and machinery were thrown into the air to an estimated height of 500 feet. The sheave wheels, which had gone down the shaft together with the headframe, were blown out and fell over a hundred yards from the pit head, completely burying themselves in the hard earth.
Somehow Equality’s physician Lucien W. Gordon had presence of mind to set up a camera, in time to catch the second geyser. In contrast to the official reports, Gordon—who compared the height of the geysers to nearby objects—estimated the first geyser to shoot 600 feet into the air (instead of 500) and the second to reach about 260 feet high (instead of 150).

Rebirth at Equality
The Equality coal mine was totally destroyed, with the damage estimated by various sources at $25,000 or $30,000 in 1913 dollars (probably equivalent to half a million or a million dollars today).

Although the 1913 flood had suddenly idled the miners, there was still work to be done. After detailed study of the mine maps, the Gallatin company engineers felt that a new shaft could be driven not too far from the old 
Equality mine surface works before and after the compressed-air rebound geyser. Credit: Coal Age
destroyed shaft. In November, 1913, sinking began as well as pumping out the oily floodwaters. Full dewatering took more nearly half a year, until the end of April 1914. The new shaft was opened, landings, entries, airways and roads built for connecting with the old shaft and works. The new shaft was much better constructed than the older one, as it was lined with reinforced concrete instead of timber, and other structures were made of steel. The old air shaft was also lined with concrete, and the surface works replaced with buildings and equipment that were strictly fireproof. The Equality coal mine was reopened within a year and worked until 1930.

Air power
Such explosive rebound of air compressed by water flooding into an underground mine is rare, but not unheard of. The geysers from the Equality mine were neither the first nor the last in the history of mining. Three weeks after Gordon’s spectacular account of the geyser at Equality was published in the May 10, 1913 issue of Coal Age, a general manager of another mining company wrote a letter to the editor recounting a similar event a few years earlier in a mine in Ellsworth, Pennsylvania. A still earlier incident from 1880 happened closer to home in a flooded mine owned by Bernhard Blume in Pinckneyville, Illinois. 

A truly spectacular example of explosive rebound happened almost exactly four years after the 1913 flooding of Equality, this time in Juneau, Alaska, in the Treadwell gold mine on April 21, 1917. Unlike the shallow coal mine at Equality, the Treadwell mine was deep—some 2,800 feet—and the prize was gold. It was a huge operation that employed some 2,000 men. The mine was very close to the Gastineau Channel, the channel between Juneau on the mainland and Douglas Island. A hole that formed at one side of the mine let an estimated 3 million tons of seawater rush in in a mere 3.5 hours. The last men were just being rescued when water and rock started cascading down the main shaft. In less than an hour, a huge geyser of seawater erupted 200 feet into the air.

Even more recently, something similar happened in South Crofty Tin Mine in Cornwall in July 1998 . Whether a geyser forms or not, the floodwater discharged during rebound is often polluted and toxic, so mining engineers have devoted significant effort to trying to predict mine rebound, which can be a major issue especially for abandoned works, which are no longer dewatered through pumping and left untended. 

©2015 Trudy E. Bell

Next time: The Great Easter 1913 Disaster in Editorial Cartoons

Selected References
A Compilation of the Reports of the Mining Industry of Illinois from The Earliest Records to the Close of the Year 1930. Department of Mines and Minerals. Springfield, Ill. For the 1880 account of compressed air rebound in the mine of Bernhard Blume in Pinckneyville, see Appendix C, page 175 “A Peculiar Tragedy of 1880” by Stanley Smith. This anecdote is preserved in several other places on the web as well, generally without proper attribution.
Andros, S.O. Coal Mining in Illinois. Bulletin 13. Illinois Coal Mining Investigations. University of Illinois. Urbana. 1915.

Gordon, Lucien W. “Phenomenal Outburst of Water at Equality.” Coal Age 3(19): 728–729. May 10, 1913.

King, Mary Lou and Jim Geraghty. Treadwell Mine Historic Trail. Walking Tour Map & Historic Guide. Juneau–Douglas Mining District. 2007. Page 8. 
“Lucien Winslow Gordon, M.D.” Memoirs of the Lower Ohio Valley. Personal and  Genealogical with Portraits. Madison, Wis.: Federal Publishing Co. 1905. Volume II. Pp. 327–329.

Morris, S. P. “Roughing It for the Red Cross.” The American Red Cross Magazine 8(3): 46–50, July 1913.

“Mine Destroyed at Equality.” Thirty-Second Annual Coal Report of Illinois. State Mining Board. 1913. Pages 248–249. This article was reprinted under the byline of inspector Paul Roebottom and the title “Flooded Coal Mine in Illinois” in the April 1914 issue of The Colliery Engineer 34: 570–571.

Obrad, Jennifer M., and C. Chenoweth. Directory of Coal Mines in Illinois 7.5-Minute Quadrangle Series. Equality Quadrangle. Gallatin and Saline Counties. Department of Natural Resources. Illinois State Geological Survey. 2005 (revised 2009).

“Old Mine Reopened.” Thirty-third Annual Coal Report of Illinois. State Mining Board. 1914. Pages 238–239.
Special Correspondent. “Flood Protection at the Illinois Mines.” Coal Age 3(22): 828–830. May 31, 1913.

Younger, P.L. and R. Adams. Predicting Mine Water Rebound. R&D Technical  Report W179. Environment Agency. Bristol. U.K. 1999. 

Bell, Trudy E., The Great Dayton Flood of 1913, Arcadia Publishing, 2008. Picture book of nearly 200 images of the flood in Dayton, rescue efforts, recovery, and the construction of the Miami Conservancy District dry dams for flood control, including several pictures of Cox. (Author’s shameless marketing plug: Copies are available directly from me for the cover price of $21.99 plus $4.00 shipping, complete with inscription of your choice; for details, e-mail me), or order from the publisher.