LOGISTICS OF DRILLING IN THE PAPUAN HIGHLANDS

Abstract

The location of the first drilling site in the Highlands of Papua New Guinea presented some unusual logistics problems. The Mananda No. 1 well was drilled by Australasian Petroleum Company Pty. Ltd. in its Permit Area 27. The site is at an elevation of 6,000 ft. above sea level on the Mananda Ridge, about 100 miles west of Mount Hagen, in an area which is largely pinnacle limestone.

After road access was discounted and several helicopter types found to be unsuitable, only one helicopter, the Boeing Vertol 107, was found to be an economic proposition for lifting rig components into the site.

The helirig used was a Wilson 90E, owned by Santa Fe Drilling Operators Inc. and was taken over from Texaco after the completion of drilling of Cecilia No. 1 well in the Western District of Papua.

Numerous supply routes were considered for the 4,000,000 lb. of materials and equipment required in addition to the rig. These route possibilities included Hercules and other large freighter aircraft from the coastal ports of Port Moresby, Lae and Madang, and combinations of coastal and river vessels, road transport and smaller fixed wing aircraft, with varying helicopter distances. Comparative costs of different routes are given. These showed that long helicopter distances with generally poor weather conditions could be quickly ruled out.

The Hercules had distinct advantages and on initial considerations could possibly have been the most economic choice, but the obstacles of having to import the aircraft, of the general unsuitability of available airstrips and of the need to mobilize all or most materials at the one time, led to the abandonment of this route.

The route finally selected for most materials was by road from Lae to Mount Hagen, Twin Otter and Skyvan aircraft to Komo airstrip and helicopters for the last eight miles to the rigsite. Each sector presented its own particular problems due to weight and length limitations, notably for casing, as well as problems due to weather.

The route chosen for evacuation of the rig was by helicopter to a base established on the Turama River and thence by coastal vessel to Port Moresby. The choice of this route was justified by the time saved, since A.P.C. was liable under the contract to pay some $2,500 per day for rig hire until its arrival at a deep water port.

Hindsight will undoubtedly show that improvements in the logistics patterns could have been made, but experience to date has tended to confirm that the basic patterns selected were the most economic.