Registro de la MSHA sobre No 3 (ID de mina 4406040). Muertes, incidentes no mortales agrupados por año, operador y controlador actuales, y contexto de la mina.
Avísenme cuando se presente un nuevo incidente de la MSHA en No 3.
STRAINED BACK W2ILE LIFTING ROCK
THE ROOF IN THE AREA WAS SLATE BOLTED WITH 4 FT CONVENTIONAL BOLTS ACCORDING TO ROOF CONTROL PLAN SANDSTONE WAS PRESENT APPROX 1 FT TO 2 FT ABOVE THE ANCHORAGE OF THE BOLTS CAUSING THE FALL OCCUR
THE ROOF GAVE WAY AT ON NEAR THE ANCHORAGE OF THE 4\ GLUE BOLTS ALLOWING AND AREA OPPROXIMATELY 15\ X 18\ X4 1/2\ TO 5\ TO FALL. A SMALL BEAM OF COAL WAS PRESENT IN THE AREA ALONG WITH A HILL SEAM IN THE SANDSTONE DIRECTLY ABOVE THE ANCHORAGE OF THE BOLTS.
APPARENTLY THE BOLT ANCHORAGE WAS NEAR WHERE SHALE AND SANDSTONE MET CAUSING THE ROOF TO FALL. 4\ CONVENTIONAL BOLTS WERE USED OCCORDING TO PROFOF CONTROL PLAN NO SANDSTONE ENCOUNTED IN 5\ TES T HOLES BEING DRILLED. HOWEVER THE SANDSTONE WAS CLOSE ABOVE THE 5\ HOLES.
THE ROOF IN T HE FALL AREA WAS SLATE. ABOVE THE ANCHORAGE OF THE BOLTS WAS SANDSTONE CAUSING THE ROOF TO GIVE WAY.
INTERSECTION FELL IN NO.3 ENTRY 2ND BREAK THROUGH OUTBY FACE. APPARENTLY THE MAJORITY OF BOLTS IN THIS AREA WERE ANCHORED AT APPROX. WHERE SANDSTONE AND THE IMMDIATELY SHALE ROOF MET CAUSING T HE FALL.
ROCK FALL BETWEEN TWO MUD SEAMS-40 FT LONG 8-10 FT THICK 2-6 FT WIDE. AGAINST THE FACE.