C—2

Mines Department Survey Parties Survey parties were maintained by the Mines Department in each of the three fields, Garvey Creek, Stockton-Millerton, and Denniston. Particulars of the year's activities in each field are as follows: — Garvey Creek General trenching and survey work was carried out at Centre Block, Montgomerie Block, and Waitahu Block, and some detailed work was done on an opencast area in the Webby Creek Block. As a result of this work and that carried out in previous years, it is now considered that sufficient information concerning the Garvey Creek area is available for all immediate purposes and that detailed work may well await the completion of the Island Block access road, which will not only facilitate transport of labour and stores but will have definite prospecting value as well in view of the exposures of the seams that will be made incidental to its construction. Centre Block. —This, the largest area —namely, 550 acres —in the Garvey Creek Coalfield, has been prospected on three sides, the western, eastern, and northern, the extent to which the block may extend to the south being at present unknown. Prospecting work has merely outlined the structure and indicated areas where the structure is relatively simple that warrant further detailed information. No estimate of quantities can be made at this stage. The "A " seam in this block occurs as discontinuous lenticular blocks rather than as a regular continuous seam. To determine the structure and thickness and quality of coal in " A " seam, further work by drilling or prospecting drives is necessary when road access is provided to the Island Block. Waitahu Block. —This block is situated on the main ridge about one mile and a half north of the junction of the Waitahu and Montgomerie Rivers approximately 1,500 ft. to 2,300 ft. above the Waitahu Yalley. It has an area of approximately 160 acres, and is roughly triangular in outline, its greatest length being 50 chains and width 35 chains. One seam was traced along the southern extremity and thirty trenches were dug, but nowhere was more than 10 ft. of coal exposed. Only in the south-east corner was the seam found workable, where it averaged 6 ft. to 8 ft. thick for 10 to 15 chains. Two factors, (a) its inaccessibility and (b) the nature and thinning of the seam, preclude the possibility of the Waitahu Block offering any mining prospects in the immediate future. Montgomerie Block. —This block is situated north-east of the junction of the Montgomerie and Waitahu Rivers on the Montgomerie side of the divide. "A" seam outcrops were traced for 60 to 70 chains and twelve trenches were dug to prove the seam. It exhibits the marked irregularities typical of the field, and in view of its isolation further detailed investigation cannot be justified at the moment. Webby Creek Block. —An opencast area of approximately 3J acres situated in Webby Creek Block about one mile and a quarter from the Garvey Creek Road on the proposed route to the Island Block has been closely trenched, several new trenches having been dug, and existing ones extended to the full width of the seam. As a result of this work it has been estimated that the area contains 125,000 tons of coal from which 270,000 cubic yards of overburden would have to be stripped, while a further 30,000 to 35,000 tons of coal is possible with a similar overburden to coal ratio. This area will be further investigated when the road to Island Block is constructed to the site of this opencast.

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