193. SUBMARINE COAL

The previous item (#192) made me curious about coal under the ocean, so I did some searching. It's interesting that coal was originally called "sea-coal" and was linked with the sea:

It is usually assumed that the term 'sea-coal' reflects the ease with which coal may be gathered on the seashore in some places, giving a hint as to how coal in this island was first discovered and (appropriately) named. The Oxford English Dictionary says: "Possibly in early times the chief source of coal supply may have been the beds exposed by marine denudation on the coast of Northumberland and South Wales." The antiquary, Leland, visiting the north in 1769, used the word 'sea-coal' in a similar sense: "The vaynes of the se-coles be sometyme upon clives [cliffs] of the se, as round about Coket Island."

Sea-coal, as coal washed up by the sea, and recovered from the shore, is current still in local use, referring to fragments collected off the beach into sacks and wheeled away on a bicycle (traditionally) for local use.

Collecting Sea Coal
The process was noted in the 1930s by J.B.Priestley: "Along the coast road between Sunderland and Seaham Harbour, we came upon quite a number of men riding or wheeling bicycles loaded with two or three small sacks of coal. I heard afterwards that these men descend very steep and dangerous cliffs near Seaham Harbour and pick up coal from the shore. They were now going to Sunderland to sell the coal."Source

It turns out that undersea coal mining has a long history, and is widely practiced:

The known submarine areas from which coal is mined at the present time, are Chili, Japan, the East and West Coast of Northern England, under the Firth of Forth in Scotland, on Vancouver Island, in British Columbia on the West Coast and Cape Breton Island, Nova Scotia on the East Coast of Canada.Source

China recently joined the club:

Chinanews, Aug. 16 - China's first try of exploiting a seabed coal mine concluded successfully in Shandong's Longkou on August 14. During the operation, mechanized top coal caving technology was adopted for the first time in seabed coal mining, filling the blank in the world undersea mining technologies.

Beizao Coal Mine, a branch of Shandong Longkou Mining Group Company, is the first company in China to exploit undersea coalfields. On June 18, prophase work started at the coalfield with a 4.4 meter thick coal seam and a reserve of 89.2 kilotons, 359.5 meters below the Bohai Sea.Source

These mines can extend quite a distance into the sea:

The workings in these mines extend from a minimum of 0.7 miles to a maximum of 2.2 miles from the shore.

It may be of interest to note that Dominion No. 4 Colliery, recently closed, had penetrated further seaward than any other colliery in the field, the main deeps having reached a distance of 3.6 miles from the shore. It is also of interest to note that the deepest submarine mine in Nova Scotia, or probably anywhere, was, prior to its closure, No. 2 Mine of the Inverness Coal & Railway Company, where nearly 3,000 feet of cover had been reached.Source

Apparently, the longest undersea tunnel ever dug is the Seikan Tunnel (53.85 km) connecting Honshu to Hokkaido in Japan (click to enlarge):

-- by JD