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FIGURE 2— Townsite plan at Cassiar.

structed and used to transport the ore from the
6400-ft (1950-m) elevation to the 4800-ft (1463-m)
elevation, a drop of 1400 ft (427 m), where it was
loaded and transported to the mill in 10-ton trucks.
This chute, however, became constantly clogged and
was abandoned in 1956 in favour of a 14,600-ft (4450-
m) aerial tramline which extended from the mine at
elevation 5800 ft (1768-m) to the mill at elevation 3525
ft (1074 m). The operating capacity of the tramline
was 1800 tons per day, with each of the 180 buckets
carrying 34 ton net weight.

The mine had been developed and operated as a
summer operation from 1952 until 1962. The reason
for this part-yearly operation was the fact that suf-
ficient ore could be mined and transported during the
summer months to satisfy the yearly feed to the mill.
By 1962, the strengthening of markets and a greater
demand for the Cassiar fibre eventually resulted in a
year-round mining and milling operation. An im-
portant addition was a rock reject plant, located at the
mine site, to concentrate the ore and improve the grade
of the fibre transported to the mill stockpiles. During
this time, the mill had progressed from a 250-tpd oper-
ation to a 1600-tpd operation. As improvements and
additions were being made to all operations of the
plantsite and mill, the tonnage increased yearly until
it reached 2000 tons per operating day by 1966.

The progression, in a part of the province con-
sidered remote and hostile, from a small seasonal oper-

ation to a 12-month operation had shown that the
efforts and perseverance of the Cassiar management
team had been well justified.

The operation, by 1966, was increasing in product-
ivity at a rate that required a change in over-all con-
cept. It was becoming increasingly evident that the
tramline was under capacity for the mill demand. The
remedial approach was to improve and widen the exist-
ing 6-mile (9.6-km) haul road from the mill to the
mine site and supplement the tramline with trucking,
using trucks ranging from 28 to 60 tons capacity.

By 1970, the milling operation had progressed to a
rated capacity of 2200 tons per operating day, with
36% of the total ore delivered from the mine by
truck. The demand for fibre by 1970 had progressed
to in excess of 75,000 tons of fibre produced; conse-
quently, a new mill extension was constructed adjacent
to the old mill, increasing the operating capacity of
the mill as well as the fibre production from 250-275 to
400 tons per day and also increasing the amount of
recoverable fibre by adding one additional cement
fibre grade (AZ).

The tonnage processed by the new milling complex
had, by 1975, increased to 3300 tons per operating day,
with truck transportation outstripping tramline trans-
portation by nearly 2 to 1. It was during this year
that the new tramline was commissioned. Studies had
been initiated as early as 1971 to determine the most
economical method of transporting ore from the mine

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