| Show WATER FLOW IN MOFFAT TUNNEL api dpi anthe e night of february 28 a large water course delivering ill approximately gallons per minute was cut m the e main heading of the railroad tunnel at east portal the round had ad been shot and the mucking crew went in to clean up while the mucking machine was clearing the fly V rock lock and shifter placed laced working toward the heading the p a NO mn cluster T of lights s in the heading and returned to crosscut 10 feet back for tools t he upon ja returning return iff to the heading where the pressure of the inflow from the floor had started to shift tile the muck pile m foreman fore reman man received the impression thethis that his lights had been yards moved v ed the water then broke through lifting the forty I 1 carr of rock back about 20 feet so that some of it was carried ned i against the approaching mucking machine and ham the work of rescuing it and moving it up the 08 per cent grade past the crosscut to the apex 1300 feet east cast by the time the crew reached crosscut 10 the water was waist deep but as it flowed through the cross and into the water tunnel heading which is parallel with and 75 teet feet to the south of the main heading and 32 feet head of it at the time there was an opportunity before this working was flooded at a m to remove most of the machinery build a bulkhead of sand bags across the main heading east of crosscut 10 and set up pumps to direct the flow east through the water tunnel to crosscut 8 and thence out through the foot railroad bore thus leaving the enlargement operations west of crosscut undisturbed for two days the gallon per minute flow ran 4 inches deep over the railroad tunnel tracks after which the water subsided to 1500 gallons a minute by the ath of march at which stage it remained for about thirty days by april 10 the flow in the main heading was down to 1000 gallons per minute and drill holes in the water tunnel which was being driven ahead struck water from then the flow in the water tunnel has increased until on may 1 it was gallons per minute while that in the main heading had decreased to the nominal amount of about gallons per minute as the water bearing seams were tapped by the water tunnel low head electric centrifugal pumps mounted on flat cars were used to the headings about 1200 feet of discharge pipe being moun mounted tedon on strings of trucks extending to the apex and added to as the water receded subsequently the pipe lines were placed along the side of the tunnel and permanent installations with bumps sump made it was found that gravel and rocks that washed in from the seam had filled the main heading for about feet at the time of the inflow the headings were over 2700 feet beneath the surface of the continental divide where the barren rock gave no indications other than a dyke running along the backbone of the that the water bearing seams existed for about thirty days preceding the flood wet seams carrying as high as gallons per minute had been encountered in the gray granite and gneiss throughout hout feet driven since march 1 in the water tunnel the roof and side walls have dripped large quantities of water but no main seam has been cut on may 15 the headings became dry C A B engineering news record |
