Sessional_Paper_1948 — Page 181

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In order to safeguard the water supplies for the future it is important that the local severe erosion of the hillsides should be checked, and that afforestation should be greatly extended.

Tai Lam Chung Scheme. I discussed with the Engineer (Construction), Mr. Jackson, the alternative sites that have been proposed for the main dam. The lower site, would require the dam foundation to be carried down to a maximum depth of 60 feet below the valley floor, which is subject to tidal flow. Also, drilling has disclosed a small area of weakness and fissuring at the lowest point; this area of weakness is probably of some importance and there is evidence that it is part of a line of weakness that has the site of the valley itself. Apart from this weak point the foundation appears to be good, and the visible sides of the valley at the centre line are of good strong granite free from serious fissuring.

The upper site, on the other hand, on the valley floor and up the greater part of the valley sides, is wholly of good fresh granite. The lowest section is well exposed in the stream bed and is strong and fresh throughout; it has some slight degree of horizontal jointing but no more than could be suitably dealt with during construction. Away from the valley, the extension of the dam at high levels in the form of a cut-off wall would cut across weathered rock which would involve a few feet of trenching down to the fresh rock.

The Engineer (Construction) in a statement dated February, 1948, has sum- marised the relative advantages and disadvantages of the two sites, and has shown that a dam of 190 feet at the upper site, while storing as much water as one of a total height of 260 feet at the lower site, would offer many advantages from the point of view of cost and difficulty of construction, the amount of concrete required, etc. The object of this note is to record my opinion as a Geologist that the upper site is preferable in that the foundation there is sound and well exposed; moreover it offers no special difficulties in construction, and is in every way suitable as a dam site. The foundation of the lower site, on the other hand, extends to 60 feet below tidal waters and has an area of serious weakness at the lowest point, which would have to be cleaned out and grouted to an unknown additional depth, at uncertain but considerable cost. It is true that at the higher levels the upper site would require a long cut-off wall in part in weathered rock, but resting on solid rock, but the cost of construction of this would be very small in relation to the cost and difficulty of securing the foundation at the lower site.

Control of Mining.

The question of the control of mining operations on the mainland has occupied the attention of Government for some years. The fact is that at present there is no systematic control; Government has no means of checking production and of supervising conditions of labour, and it is generally accepted that a considerable degree of illegal mining and loss of revenue to Government on royalties, leases, etc. is taking place and has taken place for some years past.

In January of this year Prospecting and Mining Regulations (1948) were published in the Gazette, and in paragraphs 3 (13) (2) (15) the Licensee is required to carry out certain provisions for safe and efficient working. I agree with the views ex- pressed in the relative papers that, by the issue of these Regulations, Government is committed to the appointment of staff suitably qualified to ensure that they are carried out.

A few years ago Mr. Kershaw, of the Malayan Mines Department, recom- mended inter alia that a Mines Overseer, with three months special training, should be appointed to effect the necessary control. The problems involved seem to me to de- mand the appointment of an officer of the standing of an Inspector of Mines, such as from most of the staff of any Colonial Mines Department; he would require sub- ordinate staff for examining beacons, checking safety measures, etc. Should a serious accident take place or a series of minor accidents it would, in present circumstances, be difficult to explain why the safety provisions of the Regulations were not being enforced.