Notes to Accompany Table 7.

a) Drilling dust loss estimate based on 1 GR/SCF
emission at Rotoclone exhaust up to and including 1974.
Although more than | drill is involved, and drilling is
often erractic in frequency, average 3000 CFM exhaust
may be assumed over 24 hours for 300 days/year, for
1974 - 8.3 million tons mined. 1970 and 1973 based on
5.2 million tons mined. 1976 based on average 5200 CFM
drills exhaust, at GR/SCF of less than 0.05 (all drills
with fabris filter baghouses) for standard operating

year.

Blasting losses averaged at | Ib. particulate loss for
every 83 tons mined.

Estimated as 0.05% waste tonnage removed.

Estimated as 0.01% ore tonnage removed.

Estimated as 2 GR/SCF emission for 65000 CFM average
for 300 operating days, plus 25% fugitive losses prior
to 1975. After 1975, only primary crushers will remain
in operation at minesite. Crushers to be dust controlled
by 2 - 10000 CFM baghouses equipped with fabric filter,
annual average emission estimated at 0.05 GR/SCF max.

f) Up to 1976, yearly average 12000 CFM at 1 GR/SCF estimated
for dryer cyclone exhaust. Once 1975 tramline and con-
centrator operational, mine dryer to be removed from ser-

vice.

Estimated as 0.05% reject tonnage. After 1975 all rejection
to be handled at Mill Concentrator, thus no dust losses
will occur as Mine Reject tailings.

Estimated as 0.005% tons ore delivered for milling.

i) Based on 1974 16500 CFM average at 0.24 GR/SCF annual
average. 1976 add 2500 CFM, 1970 subtract 4000 CFM, 1973

subtract 2500 CFM.