D-=?_

(8) What, in your opinion, was the cause of the cracking ? Also reply to the following points : — To what extent, if any, the following factors contributed towards the fracture in the hill between the gorge and the headrace and spillway : — (i) Geological weaknesses in the headrace ; (ii) The driving and operation of penstock-tunnels ; (iii) The weight of the outdoor-transformer station ; (iv) The moment exerted by the weight of water in the headrace and spillway as a force applied against the hill in the direction of the gorge ; (v) The weakening of the hill by water-absorption. (9) Does the fact that the crack occurred render the continued operation of the power-generating station impossible, presuming remedial measures to be carried out ? (10) Could the present power-house be safely operated without any major remedial measures being taken, and could the displacement of the generators be remedied ? Would it be possible or advisable to run the plant in the present condition of the machines and concrete emplacements 1 If not, what should be done to remedy this position ? (11) Having in mind the condition of fracture which exists, do you consider it advisable to construct any additional penstock-tunnels on lines of present existing tunnels ; and, if so, what would be the effect of the increased strain or pressure which would thus be placed on the hill between the headrace and the gorge ? (12) Prior to the present trouble occurring, and owing to the rapid erosion taking place below the spillway-dam, authority was given to concrete the " falls." After examining the plans and specifications for this work, do you consider the proposal a proper one, possessing reasonable prospects of success, and what is your opinion of the estimated cost ? (13) If you do not consider above proposal for concreting the " falls " a proper one, what is your alternative suggestion for dealing with this portion of the scheme and preventing further erosion ? (14) Is the scheme put forward by the Department's engineers for remedial measures the best, in your opinion, and could it be carried out at the price estimated ? (15) If your answer to No. (14) is in the negative, which other of the possible schemes put forward by the Department's engineers should be adopted ? (16) If, in your opinion, none of the schemes put forward by the Department's engineers indicates the best solution, what do you consider should be done, and what is your estimate of the cost of your proposals ? (17) Assuming you. are of the opinion that the position is or can be made quite secure without moving the present power-house, do you consider that there will be any risk in proceeding to extend the power-house on the lines which were being followed prior to the trouble of the 7th June ? (18) If your answer to No. (17) is in the negative, what additional safeguards do you consider should be provided ? (19) If your answer to No. (17) is in the affirmative, would it be practicable and safe to run the power-house up to its present installed capacity, or, alternatively, would a modification of the present installed capacity enable the present power-house to be operated with a requisite amount of safety ? (20) If, even with additional safeguards, you are of the opinion that the present power-house should not be extended, what do you consider the best method to adopt for the generation of the remaining half of the possible power at this location ? (21) Having examined the geological evidence and the formation as disclosed by the test holes, do you consider that it was reasonable to erect the dam and the power-house on the sites selected ? (22) If your answer to No. (21) is in the negative, what conclusions do you derive therefrom ? (23) Having given full consideration to the conditions of the headrace, and in the event of your opinion precluding its further use, what alternative method would you recommend for the delivery of water to the penstocks ?

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