I was attending Selby Mines Rescue station for my annual medical and treadmill fitness test when a rescue officer told me that conditions on H439s coal face at Riccall had got worse and the CO levels had started to rise due to the heating on the face. The face had a slip fault 70m from the main gate and the coal left in the gob was causing an heating.
Coal mines in the UK are required to have prepared sites with sealed concrete blocks walls started at the required dimension in all gate roads to a coalface.
The explosion proof seals in both roadways to the H439s face had been started. Equipment and resources were being transported to the Fresh Air Base for the stoppings to be made. I was told if carbon monoxide levels got any higher that rescue teams will be called to complete the stoppings. I returned home for some lunch when my alerter was activated. I phoned the Rescue Station and was told to go to Whitemoor Mine and that an emergency incident had been called due to the heating getting worse. The underground access at Riccall Mine was suspended for safety reason and all staff attending the heating on H439s face had to access the face from Whitemoor Mine.
When I arrived at Whitemoor Mine I was told that a Fresh Air Base had been set up between H439s main gate and tail gate. Rescue officers were underground and a Selby Rescue Station team were en route to H439s. I was told by the surface senior officer of the incident to go to the canteen and wait.
30 minutes passed by when the senior officer came to the canteen and called for a team to go underground. The team was chosen and I was made captain as I worked at Riccall and I had knowledge of the mine and the face, as I had been working on it the day before.
All men had been withdrawn from the mine except for a minimum staff of officials and craftsmen to cover the concrete pumping operations. All person going underground had to do so using the emergency check system at Whitemoor Mine. All operations were controlled by the Senior Rescue Officer at Whitemoor Mine Surface Rescue Control.
After checking and donning our S.E.F.A. breathing apparatus in the rescue room we gathered all our equipment which included, a mine plan, Whirling hygrometer, Sked stretcher, Microvent resuscitator, Drager gas sampling tubes and pump and Status Mentor gas analyser and the team went underground. We were transported by rope haulage from Whitemoor Mine pit bottom as far as possible in the West Conveyor Road towards the Whitemoor Bunker area. We then continued on foot to H439s Fresh Air Base which was approximately 3500m from the pit bottom. When we arrived at the F.A.B. we were told to relax and wait on standby. After an hour we were called and given a brief. I was told that the carbon monoxide levels were rising and to check the CO levels regularly and hydrogen cyanide, a toxic gas produced when plastic mesh burned. Our first task was to start installing an air sweetening system from the Fresh Air Base.We then had a 2 hour spell in breathing apparatus, building and pumping concrete at the tail gate stopping site. The team then went back on standby, as a safety team for 2 hours until the next relief team arrived. .
When the relief team arrived, we were released from the fresh air base and were told to return to the surface. Once on the surface we had a debrief then cleaned, recharged and serviced our SEFA breathing apparatus so they could be re-used. We completed all the necessary training records and Captains Report for the incident.
I returned to Riccall Mine to attend a meeting regarding the situation on H439s. By the time I arrived home I had been awake 26 hours and ready for some sleep.
On completion and simultaneous sealing of the maingate and tailgate explosion proof stoppings all men were immediately evacuated from the mine and nitrogen was pumped into district from the surface pumping rig supplied by NOWSCO. The mine gases behind the stopping were checked using tube bundle monitoring. The sealing process proved successful with no methane ignition recorded on the mine environmental monitoring system.
Note; The reason nitrogen, an inert gas, was pumped into the district with an heating was to lower the oxygen level below a point where combustion can take place. When a district is sealed, methane gas levels can quickly enter the explosive range of 5% to 15%. If the oxygen levels are reduced below 13% before the methane levels reach explosive range no ignition can occurs. The company who provided the nitrogen pumping service was called NOWSCO, an oil well service company, who specialise in pressurising blocked pipelines.
Selby Superpit 