level, so that although the bituminous sands are exposed
along the sides of all these valleys, elsewhere they are
heavily overlain by shales.

The area underlain by these bitumen-impregnated
sands has not been accurately determined, but is estimated
to be not less than 1,500 square miles and may exceed
10,000 square miles. The thickness of the tar sands ranges
from a few feet to 225 feet. The better grade sand contains
15 per cent bitumen or 0-9 barrel of bitumen per ton of
bituminous sand. Most of the sands are covered by very
thick overburden and less than 1 per cent could actually
be worked at present.

The bituminous sands have been the subject of con-
siderable detailed study, and much research ha3 been
carried out in attempts to find a cheap method of mining
the sand and a commercial process for extracting the
bitumen At present there are two plants, one at Abasand
on Horse River, 2 miles south of McMurray, and the other,

Oil Sands, Limited, at Bitumont, 50 miles down the Atha-
baska from McMurray.

The original Abasand Oils, Ltd. separation plant, built
in 1936, was burned in 1941 and rebuilt in 1942. The
results from the new plant were not so satisfactory as had
been anticipated, and although from August to November,
1942, over 11,000 tons of sand were treated yielding over
10,000 barrels of crude bitumen, the design of the plant
did not admit of economical operation. In the spring of
.1943, the Dominion Government, on the advice o*% the
Oil Controller and under an arrangement with the Abasand
Company, rebuilt the plant as a 600-ton pilot operation.

Considerable progress was made in the economical
extraction of the bitumen and when the plant was almost in
shape for a continuous operation by which costs could be

determined, it was again destroyed by fire n 1945. It has
not been rebuilt.

Test drilling was carried out from 1942 to early in
1947 to locate the most favourable areas for large-scale
mining operations. Several areas including the Horse River
reserve were drilled. In January, 1946, drilling began in
the Mildred-Ruth Lakes area 22 miles north of Fort Mc-
Murray opposite the mouth of Steepbank River. Seventy-
three wells were completed some on a half-mile and some
on a quarter-mile spacing with a few in outlying parts of the
area. “A very rich deposit of bituminous sands including
bitumen beds was found with the richer part covering at
least three square miles. It has been estimated that there
may be as much as 350,000 barrels an acre or 224,000,000
barrels per square mile in parts of this deposit. The thickest
section of bituminous beds drilled was 224 feet averaging
25-2 per cent of bitumen by weight. The high bitumen
content is explained by the presence of a number of bitumen
beds with 50 to 76 per cent bitumen content. This deposit
is sufficiently rich and large to support six plants each of
10,000 barrels a day capacity operating for 30 years. It is
thus adequate to meet all commercial requirements for

. of the deposit.

ea ne

some future time when extraction and refining of the
bitumen from the bituminous sands may be considered
feasible and economical.

Salt Deposits

A number of occurrences of common salt have been
recorded from northern Alberta and the adjacent part of
the Northwest Territories, and salt for local uses has been
harvested from brine springs for many years. Rock salt
was not discovered until 1907, when thick beds were
penetrated by wells sunk by the Northern Alberta Explora-
tion Company near McMurray. In 1936, a 200-foot bed,
700 feet from the surface, was penetrated by a drill-hole
at McMurray. Salt production was started in 1941,
and annual output has reached 19,000 tons in one year.
The McMurray deposits occur in strata of Silurian age,

and are estimated to contain more than 30,000,000 tons
of salt.

Saline springs occur at many points in the Athabaska-
Mackenzie Valley. Within 75 miles of McMurray,
springs have been found on the Wabiskaw, Firebag,
Christina, and other streams. The most. important spring
in the district is at Saline, 26 miles north of McMurray.

One of the most noted of the saline springs areas in
the Mackenzie basin is that occurring on the bank of Salt
River, which flows into Slave River about half-way be-
tween Athabaska and Great Slave Lakes. The salt obtained
from this spring is of an excellent quality, and has been
used in the Mackenzie District for many years. Other
saline springs have been reported on Tar Island in the
Peace River Valley, at Red Clay Creek on the Athabaska
River, and on the Liard and Great Bear Rivers.

In British Columbia, the occurrence 0% a strong saline
spring near Kwinitsa on the main line of the Canadian
National Railways, 45 miles east of Prince Rupert, has
attracted some attention. The brine yielded a good
quality of commercial salt by evaporation methods, and a
few tons were produced to demonstrate the possibilities
No further development work has been
done.

Gypsum

In northern Alberta and at various points in the
Mackenzie Valley, deposits of gypsum have been noted
from time to time, but distance from markets has made
any attempt to develop them impracticable. In the salt
wells drilled near McMurray, gypsum and anhydrite were
encountered, and at points along the Peace River, between

Bonille Rapids and Peace Point, beds of gypsum from 10
to 15 feet thick are to be seen.

Other deposits of varying quality are known in the Salt
and Little Buffalo Rivers, and in Jasper Park, near the
headwaters of Snake Indian River, where a bed of pure

gypsum of undetermined thickness outc-ops for a con-
siderable distance.

[39 }