1992-02-10_GENERAL DOCUMENTS - C1981017 (2)

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2- from the SE1/4 of section 18 , through the NW1/4 of section 18 and into the SW1/4 of section 7 , T. 10 S . , R. 89 W. , near the ridgeline at the southeast end of the meadow. These features were described in my report of August 30 , 1990 . The area was examine again on October 9 , 1991 , by Lew Ron Thompson, Environmen al Coordinator, and myself. The cracks first described in t e fall of 1988 had not enlarged, and in fact lesser portions of them could be found than in 1990 , much of their original extent having been filled in by surface wash or frost heaving . The pond located in the ancient slump block between the larger crack and the nearest mined-out area was full , again indicating no additional cracking toward thes old works . The single break down and away from the ridge top described in last year' s report had both deepened and widened, to up to two feet and one foot , respectively. In addition an offset of several inches had developed along short portions of this crack, which ''is parallel to the long direction and near the stoplines of longwalls 208 and 210 in the M bed and additionally is parallel to and above the startlines of longwalls 101 and 10 in the B bed. Both the direction, parallel to the pane instead of to the faces , and the offset , down on the idge-top side , are opposite of what might be expected of a subsidence-induced feature , and we remain of the opinion that these are ridgeline slumpage features . In spite of this crack' s enlargement in some places , mending by in-wash of soil material had obliterated it in others, and it was no longer than when discovered in 1990 . Other cracks in this area described in the 1990 report had not changed except for continued in-filling . A very similar crack was noted virtually on the ridge line extending northwesterly a couple hundred feet from the peak in the north center of section 18 ( highest point on Huntsman Ridge ) , parallel to the ridge and at nearly a 450 angle to the underlying longwall 208 and 101 panels . This area had been examined in 1990 and this crack was not discovered then, although it must be noted that we stood within 20 feet of it , examining the bowl below us for any signs of subsidence (none were noted) for at least 15 minutes before observing it .