MINING

Hokitika Guardian, 15 June 1933, Page 6

MINING

LAWSON’S FLAT COMPANY, / ... The Law,son's Flat Gold . Sluicing Company ~conimen./xT active milling operations last week, and' the plant has since been working uninterruptedly; The yardage being treated, with a .‘lg inch nozzle, is up to the quantity net out in the prospectus.The'debris has been practically removed from the flues, and sluicing on the later lias commenced.

'The mining history of the Callaghan’s district where the claim’is situated dates back to the GO’s, when the most accessible leads were hand worked. Then followed in tlio 70’s . and 89’s extensive sluicing operations. The government of the day spent lieaylify out of its revenue in providing water races, hut the practical difficulties in getting water to some of the proved gold-bearing faces were ’insuperable and as the hiore laclcssible belts wore worked out -the industry <vradually waned. Power is now' available to overcome those difficulties, and the Lawson’s Ait Company is utilising it in a direction which marks a new era, in gold mining on the Coast. The . claim, ns a- matter of fact is on a plateau about 3.50 feet' above tlkj only available hater supply. For this reason the fortunes of the Company are invested with general interest; The success which the trial run of the plant, indicates is cpsured, will establish a- standard for other mining enterprises to adopt, and incidentally may remove the scepticism of some of ijorne of the old mining shellbacks.

The area of, Lawson's Flat comprises 90 a ores, 21 of which - have been intensively prospected. The 21 acres will provide work for 51 years, and thi} balance of 09 acres and a further area of TOO acres are being prospected. The water ,required for sluicing is taken from a Government water''rate at i;v distance of about hall' a mile from the claim, and is pumped against a, total head of GOO feet at the rate of 2000 gallons a minute. After allowing for frictional lossejs in the t pipe lino the head available at the nozzle for sluicing is 100 feet. The plant consists of a twonstage turbine -pump constructed by the Pulsometer Engineering Company, of Retailing, a pump universally in use, in mining enterprises. It U ;driven by a GOO h.p. Grompton-Parkinson motor, the electrie power being supplied l\v Wo»t-, land Power, Limited, from their hydroelectric station at Dillmans.

Tlie improvements in the design ia-nd efficiency of the modern multi-stage centrifugal pump which is now universally used, for forcing water to great heights, make possible the method of operation which lias . been adopted at Lawson's Flat. A difficulty when high levels ip.resluiced is tire disposal of tile tailings. In a claim situated ris Lawhon’s Flat its, and where tiro values:warrant it, the cost of pumping the water is offset to a large etxent by the natural facilities provided for disposal of the tailings, which hi the present o’flo discharge with a steep drop into. German Gully some 200 feet, below the sluicing face.

The 50® Jnrse power motor ensures a nozzle delivery of seven "heads of water. In, the trial running more than this quantity. was discharged!

A tunnel 750 feet long to convey water from the race to the , pump lute, a pipe line 3000 feet long, the pumping and power unit, . two . tailings •tunnels, a. tramway, 'and the gold-slaving tablets, renect credit on the designing engineer, Mr J. S. Langford, whose original plans it was found necessary to alter in only one or two unimportant ’respects. The checking of the prospecting and the reporting on the mining features of the proposition were nndertaken hy Mr John Henderson, mininif engineer, and the enginceririg features wero reported on hy Mr u, A. Campbell, civil engineer. A satisfactory feature from the shareholders* point of view is that everything has been carried out according to the prospectus promise. Capital costs have 'been exceeded only in instances where the • increased . exchange o,ii imported material was concerned. The promise of operations commencing in June has also- been realised, a, fact largely due to Mr C. Clock's control of the- construction, work. The prospectus of the company: was filed with the Registrar om January 28 so that active operations practically four months from that date: show that there ha s been no dallying with the work.