Elders-NZFP big in coal

Press, 6 December 1989, Page 43

Elders-NZFP big in coal

By

NEILL BIRSS

If the mining, recycling, and forestry giant, Elders Resources' NZFP, wanted to get into tourism, it should find a way of letting people see long-wall coal mining. The company’s coal interests are on the huge field that runs under the wine-producing Hunter Valley of New South Wales, and extends about 100 miles to and under Sydney. The company is shipping tens of millions of dollars of coal a year, most of it to Japan, though even the Commonwealth home of mining, Britain, gets some hearth coal from Elders Resources NZFP. In its last financial year, ERNZFP bought Saxonvale and Newcastle Wallsend Coal Company. ERNZFP then merged its coal interests with Oakbridge, Ltd, leaving it with a controlling 49.1 per cent stake in Oakbridge. ERNZFP now has huge mines both opencast and underground. Long-wall mining helps keep underground coal extraction competitive with the surface pits. The Ellangong mine of ERNZFP uses the long-wall technique.

Underground, the 186-metre wide block marked for long-wall cutting is chopped out at an average of 680 tonnes an hour. A metal spherical cutter on a swinging arm moves along the wall on a rail, gouging out the coal which falls on to a conveyer.

A 3000-tonne steel system of shields, each propping up to 800 tonnes of rock supports the roof a few metres behind the advancing wall. The shields edge forward behind the cutter on marching steel legs. As the support moves forward the roof sags and then collapses. Mr Mike Barrett, the manager of Ellangong, says the technique to maximise profit in a long-wall mine is to balance the amount of long-wall mining with traditional mining.

Traditional mining, but still using automated cutters, on smaller fronts drives roads separating the giant blocks for the long-wall extraction. When a long-wall block is cut out the gear is dismantled and taken 7km to the beginning of a new block. The Ellangong mine has about 200 km of road open to service

new and developing long-wall blocks. A long-wall face is awesome. The cutter shrieks as it rips out the coal and, a few metres behind, the roof groans and crashes down. Australian miners are advanced in their use of the longwall techniques on the large, deep bands of coal. About 20 long-wall systems are working in the country, compared with about 175 in the United States. A short distance from ERNZFP’s underground mines is the company’s big opencut mine at Saxonvale. The mine was opened in 198182 by BHP and was to have been one of the biggest in New South Wales. Coal prices did not hold up, however, and BHP sold it in October, 1988, to ERNZFP. The company has about 4300 hectares in two adjacent leases and is seeking more ground. In all, reserves for opencast mining on the two leases are estimated at 1.6 billion tonnes, of which the potential for opencast extraction is 400 M tonnes. The remainder may be suitable for underground mining. . Moving the overburden, shifted first by bulldozers, are 21 dump

trucks, each costing about SNZ2M and able to carry 172 tonnes. In one of the two pits of the mine, the Whybrow, the coal seam is 5.5 metres thick and close to the surface (it begins about 10 metres down). Large electric shovels are being moved into the Whybrow to begin what is expected to be 35 years of production. In the other main pit of the mine an excavator which bites 26 cubic metres of rock or coal at a mouthful is the main mining device.

Five more 1 huge dump trucks and two large bulldozers are being added to increase output. Twelve months ago, the opencast mine employed 140 people. Now there are 310, and the total staff is being built up to 374. A nearby Bulga pit will be opened when coal prices allow.

The Elders NZFP coal investment is huge. And the company also has interests in extracting gas from coalfields. The loss of an independent N.Z. Forest Products has at least given New Zealanders a chance to buy into Australian coal mining through .'a quasi-local company. •