Expansion of central production
facilities at the Kutubu Petroleum
Development Project in Papua New Guinea
(PNG) required excavation of a steep
hillside overlooking operating crude
oil processing, storage and pumping
facilities. Drilling and blasting were
used to remove a large volume of rock
which varied from hard limestone to
soft sandstone, with zones of soft clay
and many underground caverns. Similar
ground conditions had made it very
difficult to predict and control blast-
ing results during previous excavation
in this area.
Special conditions of the project
included restrictions on ground
vibration levels at a high pressure oil
pipeline and pump station within 100m
of the blasting area, and a prohibition
on any flyrock. As work progressed,
some blasting was necessary with 20m of
installations being constructed on the
levelled project site. Thus blast
design, drilling and charging were
carefully controlled to avoid any
incidents which could interfere with
oil production or progress of the
construction project.