Ground Water Reduction Analysis At Gold Mine Area Td-5010a Underground Mining Toguraci Pt Nusa Halmahera Minerals, Halmahera Utara District, North Moluccas Province

Abstract

Toguraci underground mine PT NHM is an underground mining that has a
problem on groundwater inflow. It has reached room temperature 38 – 42oC and the
average temperature of groundwater 70 – 74oC. One of the highest temperature
cause the presence of groundwater flow in front of mining work. Besides the
groundwater flow inhibits production activity as worker and the heavy equipment
can’t enterence on that area, so need an efforts to reduce the groundwater in the
area of TD-5010A decline 9.
An Investigation doing to some determine the characteristics of the aquifer at
the location, including packer test on the ore body, rock permeability values of 0.007
m/day were classified as igneous rock types. The other of test is pumping test,
output of that test is hydraulic coefficient 22.77 m/day, transmissivity 388.84 m2/day,
storativity 8.78 x 10-5. The result of characterize the rock is classified as fracture
aquifers.
Based on the result of above the calculated, groundwater flow rate obtained
at 1036.98 m3/day/m, if the progress of mining is 3 m so discharge of groundwater
counted 36 L/s. Additional recommended is to change 16,7 L/s pump specification
with pumping capacity.