EIACP (PC-RP) on Environmental Problems of Mining

Lady Rangi Mica Mine

A pegmatite vein 1.2 to 1.8 m wide and dipping almost vertically, passed through a hill from east to west. The hill was about 75 m high. The vein was developed by a number of levels and winzes upto a depth of about 96 m measured from the top of the hill. Access to the vein was through two shafts and an adit. The Old shaft, only 9 m deep, was near the top of the hill and had its landing in the Intermediate level. The bottom 1.5 m of the shaft was supported by timber props and laggings. This shaft was not provided with ladders and was not used as a travelling way. At its bottom there was a substantial barricade to prevent entry of persons into the mine for theft of mica. The New shaft was 10 m west of the Old shaft and was 35 m deep. This shaft was provided with ladders and platforms, each ladder being about 4.5 m long. The adit was driven from near the foot of the hill and served as the main travelling and haulage road. From the point where the adit met the pegmatite vein, there was a level drive, named No.3 level, which extended upto the western extremity of the workings and there it connected with the New shaft.

The ventilation of the mine was natural; the two shafts being the intakes and the adit being the return. The adit and No.3 level were roughly 1.65 m wide and 2 m high and were laid with a 0.6 m gauge track for transporting materials. A petrol-driven compressor was installed on the surface near the new shaft and a compressed air pipeline was taken down through the New shaft and along No.3 level.

A major portion of the vein above No.2 level had been completely extracted and as there was no demand for mica then, stoping had been discontinued for several weeks prior to the accident. Thereafter, work had been concentrated in the lower part of the vein where development was being continued below the 6th level.

On the day of the accident, at about 9 a.m. 42 miners had gone into the mine and work proceeded normally until 2 p.m. The Mine In-charge, after inspecting the lower workings, ascended to No.3 level where the workers told him that smoke was coming into the mine. To find the source of the smoke, he went westward along No.3 level and found smoke coming down No.1 winze. He then went to the various winzes and shouted down them to tell the workers to leave the mine. After doing this he went out of the mine by the adit followed by workers from No.3 and No.4 levels. On reaching the surface, he went over the hill to the top of the Old shaft and found the timber at the bottom of the shaft burning. He sent a man to inform the Manager and then returning to the adit, he saw thick smoke coming out of the mine. Taking a hurricane lantern he entered the adit but he had hardly gone 30 m when his knees gave way and he fell down but managed to crawl out of the adit. On reaching fresh air he became unconscious and could not take part in the subsequent operations. The “durwan”, whose brother was still inside the mine, attempted to enter the adit. He was overcome by the fumes and was later carried out of the mine by other workers.

On receiving information about the fire at 2.30 p.m. the Mine Manager immediately proceeded to the old shaft where he found a gang of coolies throwing water on the fire. Water for this purpose had to be carried from near the adit over the hill. The manager obtained and fitted two ladders in the Old shaft so that the fire-fighters could go close to the site of the fire. The fire was advancing towards the New shaft so some people carried water down that shaft and tried to quench the fire from that side.

At about 4 p.m. the Divisional Superintendent arrived at the scene and attempted to enter the adit. He had hardly gone 7-8 m when his candle extinguished and he had to come out. He went down through a winze and got a mechanic to open a “T” socket in the compressed air pipe with a view to blow the smoke up No.1 winze and prevent if from entering the mine. The fire-fighters were trying to quench the fire by throwing earth and water on the fire. At 7.45 p.m. the fire was under control and at 9 p.m. it had been quenched sufficiently to permit the Manager and others to enter the mine. They found seven dead bodies at various points in No.3 level and some more bodies on the ladders and platforms of the different winzes. Inspection of the lower workings was not possible on that night as they were full of noxious gases.

In all 19 persons had died in the accident; 15 of them had been working below No.6 level, 3 were working in a winze below No.4 level and one was the durwan who had attempted to enter by the adit through which smoke was coming out. All those who were employed in the shallower parts of the mine had been able to come out but for those working in the deeper parts, the journey was long and tedious with numerous ladders to climb.

According to the company’s doctor, the cause of death was suffocation by CO2. He had however not examined the blood of any of the victims to determine definitely the cause of death. The Inspector of Mines, who inquired into the accident, was of the view that death was mainly due to CO poisoning.

The fire had started at the bottom of the Old shaft and extended along the intermediate level to a distance of 6 to 7 m on both the east and west sides. Ten timber sets, each consisting of two props and one bar with laggings above the bar and behind the props had burnt. Burning of so much of, timber had produced sufficient quantity of CO2 and CO to pollute all the passages of the mine to a dangerous extent.

Investigation into the accident revealed that there was a jungle fire in the vicinity of the Old shaft. No person was employed on the surface near this shaft. It is probable that some dried leaves had been blown into the Old shaft and accumulated at the bottom. An ember from the jungle fire blown into the shaft must have ignited the dry leaves which in turn ignited the timber supports and the wooden barricade at the bottom of the shaft.

The Inspector criticized the conduct of the Mine In-charge in that instead of simply warning the workers by shouting, he should have himself descended to the lower levels to warn the men and to help them to escape. He also criticized the Manager who should have tried to close the bottom of No.1 winze in order to reverse the air in the Old shaft. If these measures had been taken, many of the lives which were lost might have been saved. In extenuation, however, he pointed out that neither of the officials appeared to realize the grave nature of the occurrence which was entirely outside their previous experience.

To prevent such accidents in future the Inspector suggested that owners of underground mica mines should take the following steps during the months of January to July:-

1. Remove all vegetation for a radius of about 50 meters around any mine entrance.
2. Remove all accumulations of leaves in the vicinity of any shaft or inside the shaft.
3. Appoint a watchman for shafts which are not normally in use to keep a watch on the shafts during the hot weather when jungle fires are rife.
4. Build a stone wall about 2 m high around the month of all unused shafts.