technical report on the nechalacho deposit, thor lake project ...

18. OTHER RELEVANT DATA AND
INFORMATION
The text below is largely from the Scott Wilson RPA <strong>report</strong> (2010) as Avalon has not completed
additional engineering work on the mining process, infrastructure or economics at this time.
The PFS assumes that the ore will be concentrated at Thor Lake and barged across the Great
Slave Lake (GSL) to Pine Point for hydrometallurgical processing. The layout of the two sites
are shown in Figures 18-1 and 18-2.
MINING OPERATIONS
Underground mining of the Indicated Resource of the Basal Zone was investigated for the prefeasibility
study. The study included mine design, production scheduling, selection of equipment,
estimates of ventilation, heating, pumping backfill, fuel, and labour requirements, and
preparation of cost estimates for use in a cash flow and to support Probable Mineral Reserves.
MINING METHOD
The majority of the Indicated Resource of the Thor Lake deposit lies directly beneath and to the
north of Long Lake approximately 180 m below surface. The mineralization does exist from
near surface downwards however the highest grades exist at the bottom of the deposit at the
base of the Basal Zone. Open pit mining has not been considered in any detail due to the lower
grades near surface and the magnitude of the surface disturbance which was unacceptable to
Avalon and was considered to be a major impediment to obtaining permits. The deposit is
planned to be mined using underground mining methods.
Access to the deposit will be through a ramp collared to the west of Long Lake. The
Nechalacho deposit is planned to be mined by underground methods to access the higher
grade resources at the base of the deposit and to minimize the surface disturbance. Ground
conditions are expected to be good and primary stopes are expected to be stable at widths of
15 m. In light of the high value of the resources in the Basal Zone, the use of back fill is
proposed and mining will be done with a first pass of primary stopes followed by pillar extraction
after the primary stopes have been filled.
Technical Report 43-101 – March 13, 2011 Page 18-1
Prepared by Avalon Rare Metals Inc.