MINERALS YEARBOOK, 1967 Corp.616 
 
 Employment and Injuries.—Final em- mineral fuels industries except
coal—are ployment and injury data for 1966 and shown in table 4. 
preliminary data for 1967—excluding all 
 
Table 4.—Employment and injury experience in the mineral industries

Year and industry 
Average 
men 
work- 
Days 
active 
Man- 
days 
worked 
Man- 
hours 
worked 
Number of 
injuries 
Injury rates per 
million man-hours 
 
ing 
daily 
 
(thou- 
sands) 
(thou- 
sands) 
Fatal Nonfatal 
Fre- Severity quency 
1966: 
 
 
 
 
 
 
Coal and peat              Metal                     
287 
52 
220 
264 
63 
14 
494 
111 
  17 -- 1 
 34.44 10,234 9.02 9 
Nonmetal                  
29 
258 
7 
57 
-- 1 
 17.39 626 
Sand and gravel            Stone                     
 
Total'                  
 
1967: P 
714 
16 
176 
69 
126 
1 
1,059 
9 
20 
 18.89 409 
 
1,098 
192 
211 
1,729 
-- 39 
 22.55 3,192 
 
 
 
 
 
 
 
Coal and peat               
Metal                     
Nonmetal                  
255 
5 
35 
215 
26 
249 
55 
(2) 
9 
431 
1 
69 
-- 14-- 4 
32.48 1,46257.71 519 
Sand and gravel             Stone                      
 
Total'                   
620 
120 
159 
196 
98 
23 
933 
187 
1 15 
17.15 6,677 
 
1,035 
179 
186 
1,622 
1 33 
20.97 4,251 
P Preliminary. 
' Data may not add to total shown because of independent rounding. ' Less
than 3~ unit. 
 
REVIEW BY MINERAL COMMODITIES 
 
MINERAL FUELS 
 
 Coal (Lignite) .—Production and consumption of lignite coal, continuing
its upward trend, increased 17 percent over 1966 quantities, to an alltime
high of 4.2 million tons in 1967. Production value increased 14 percent,
to $8 million. 
 Of 21 respondents, four operators—Knife 
River Coal Mining Co.; Truax-Traer Coal 
Co. Division, Consolidation Coal Co., Inc.; 
Baukol-Noonan, Inc.; and Lignite Division, 
The North American Coal Corp—pro- 
duced over 90 percent of the State total. Operation of the unit-train transportation
concept—one commodity, one destination—was initiated by Northern
Pacific Railway Co. to serve the 172-megawatt powerplant of United Power
Association near Stanton. The entire train, more than 4,000 tons (42 cars),
can be unloaded in less than 10 minutes. The plant was supplied by the Indian
Head strip mine near Zap owned by The North American Coal