SILTING COMMISSION.

Auckland Star, Volume XLI, Issue 133, 7 June 1910, Page 5

SILTING COMMISSION.

SOME MORE PROPOSALS.

EXTRACTION COMPANY'S • OPERATIONS. The Silting Commissi6ners continued hearing evidence yesterday afternoon. Mr. Ferguson, the chairman,—said he had been informed that Mr. H. H. Adams (whom it was proposed to call) 1 had a schema for the solution of the tailings difficulty, but wanted some sort of understanding that he would be recompensed if his suggestions were used. Mr.. A. Hahna - mentioned that Mr Kangswell,. of the Paeroa . Gold Extrac tion Company, also had a scheme -which he was ready to guarantee would have the desired effect. He was willing to guarantee it to the extent of £5000 or £ 10,000. The-., chairman said the Commission could hardly accept such a proposal. It was agreed that Mr. Adams be asked to explain his proposal, and Mr. KingsweU also undertook to furnish particulars of his scheme. ■ H. W. Hopkins, metallurgist, employed by the Waihi Company at Waikino, called by Mr. Myers, said 80 par cent of the stuff they treated would pass throug-i a 200 mesh. Assuming tho. total solids that had gone into the river in the last fifteen years to be five million tons, and that was a low. estimate, this was sufficient to fill up tha river lor '25a miles. As a matter of fact, only some 7 miles past the junction, and patches below the junction, had silted up, showing that most of the stuff bad gone away to sea. Three-fifths of the total had gone away, and this approximated in its nature to 80 par cent of the present stuff. Investigations showed that there were at present little or no tailings in the river that would pass through, a 200 mesh. With the present system of treatment he thought a dredge at the mouth of the Waihou would be all that was necessary to keep the river clean. The chairman had expressed a fear that the deposit of slimes on the land by floods was going to be worse than the present trouble. Witness had made calculations which showed that the maximum amount of solids in ths river in flood time would be in the proportion ol 13.500 parts of water to 1 of solids. This meant that only about one barrow load would be deposited on an acre of land.

W. P. Govaine, engineer, of the Waihi Company, confirmed the evidence of Mr. I'raser and the other experts called by the company.

This closed the evidence for the mm ing companies.

Mr. A. Hanna then opened the case for the Pneroa and Waihi Gold Extraction Company, which has rights over nine miles of river bed, and Is now working the tailings. He pointed out that in the river there were about two million tons of tailings •which assays showed were worth 12/G a ton, so that about £1,000,000 was lying useless." The company would treat about 500 tons a day, anil if there were no further accretions of coarse tailings, the company's operations would gradually clean the river, as they would grind so small that the residue would all be carried out to sea. Mr. Hanna pointed out that his clients had an indefeasible title to nine miles of river, the licenses having been granted by the warden after a most ex-haustive-hearing: but, apa.rfc~fr.om this fact, the Company's operations would, be beneficial and not detrimental. They would be beneficial because first, they would clean the river; second, they would save a lot of gold that would otherwise be lost; third, they would be a source of revenue to the local body and fourth, they would give employment to a lot of labour. Counsel also objected to the'proposed cut at Pereniki's Bend, as this would prejudice his Company's rights.

Mr. H. H. Adams attended, and at , the request of the Chairman explained his scheme to Mr. Chas. Rhodes and Mr. Grace in camera. Later, the Chairman announced that as the scheme was not based on the quantity of silt accepted by the Commission as being deposited in the Ohinemuri, it would not be advisable to wait for the details which Mr. Adams said would requirea -week to prepare.

Mr. Cotter, in referring to the proposal of Mr. Clayton for protective, works on the same plan as those carried out at the Hutt, quoted figures to show that something under £SOO was the total amount; of -drainage rate collected there, and ■this showed that it was a very, much smaller matter than they had to face at Paeroa.

B. Mi Aitken, manager of the Extraction Company, gave evidence in support of Mr. Hanna's opening remarks. Witness reckoned it would take his company 14 years to treat the tailings in •the river, and to temporarily give relief from floods he suggested stop banks at the places where the waters now overflow.

P. N. Kingswell, managing director of •the Extraction Company, placed an offer before the Commission to cope with the difficulty caused by the. silting'up of the rivers. The company at' present can treat 500 tons a day, and they offered to double the plant providing the Government or local authority would advance the capital required—£3o,ooo—the company to pay interest, etc. Further, the company was willing to enter into a five years' contract for the dredging of the Waihou and delivering the material on .the banks. The company would provide all plant, and do the work at the rate of 6d per cubic yard for 5000 cubic yards a week, and a reduction for larger quantities.