Last edited Thu Jan 23, 2014, 06:32 AM - Edit history (2)
. . . 1972-73 by the Bureau of Mines. Results of that test can be found at the following link (beginning on page 20):
http://archive.org/stream/pumpedslurryback00cola/pumpedslurryback00cola_djvu.txt
You'll notice that it was in abandoned mine workings where the test was conducted. However . . .
"Hydraulic backfilling was developed during the late 1800s and early 1900s and was used in about one-fourth of the anthracite mines for such purposes as to extinguish mine fires, to arrest the development of progressive pillar failure known as mine squeeze, to permit the reclaiming of pillars, to dispose of unwanted mine refuse, and to protect the surface. The practice of backfilling by the coal industry in the United States decreased after World War I with the decline of the anthracite industry. In domestic bituminous coal mining operations, backfilling has never been common practice." (emphasis added)
http://www.techtransfer.osmre.gov/NTTMainSite/Library/pub/psb/section1.pdf
FWIW: In northern West Virginia and southwestern Pennsylvania---where water sources and supplies continue to be damaged and destroyed---some of the damage and destruction by the intentional subsidence from shield-support longwall mining could have been (might yet be?) reduced by backfilling or backstowing mine wastes. But then, again . . . (** tsk **) . . . it's obviously more "technologically and economically feasible" to simply continue dumping mine wastes in every available hollow, burying more streams.
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Edited to add:
Years ago, I became aware that backstowing of mine wastes was mandatory in Germany; and, therefore, it was more than a little disturbing to realize how Germany's RWE/Rheinbraun (the then-parent company of our friendly neighborhood coal operator) was sorta undermining water sources and supplies but not backstowing! Anyway . . .
The following link should give some indication of what other folks can expect if/when longwall mining begins deliberately subsiding in their neck of the woods, too:
http://www.scottchurchdirect.com/ted-williams.aspx/sagging-streams?pg=1
(As we used to say way-back-when: "Take that gob and shove it . . . . . . back in the mine!"