Coal Resources, Reserves, and Mine Sizes, Colorado
Category Type of Mining Total
Underground Surface
Demonstrated Reserve Base      
    (Million Short Tons as of January 1, 2000) 11,829 4,774 16,604
Estimated Recoverable Reserves      
    (Million Short Tons as of January 1, 1997)      
    Sulfur Content (pounds per million Btu)      
      < 0.61 (low sulfur) 5,565 380 5,945
      0.61-1.67 (medium-sulfur) 640 3,365 4,005
      > 1.67 (high sulfur) 81 14 95
      Total 6,286 3,759 10,045
Recoverable Reserves at Producing Mines, Year End 1999 415 202 617
Number of Producing Mines in 1999 8 4 12
Production Range (thousand short tons)      
     1,000 and over, number 5 3 8
                   percent 96% 96% 96%
       500 to 1,000 number 0 0 0
                   percent 0% 0% 0%
       100 to 500,  number 3 1 4
                   percent 4% 4% 4%
        10 to 100,  number 0 0 0
                   percent 0% 0% 0%
            < 10,   number 0 0 0
                   percent 0% 0% 0%


       Notes: "Recoverable Reserves at Producing Mines" includes no reserves at mines that produced less than 10,000 tons in the calendar year.  These small mines are not required to provide reserves data.  Excludes silt, culm, refuse bank, slurry dam, and dredge operations except for Pennsylvania anthracite.  Totals may not equal sum of components due to independent rounding.
* = Data round to zero. W = Withheld to avoid disclosure of individual company data.
       Sources: Energy Information Administration, Coal Reserves Data Base program and Form EIA-7A "Coal Production Report."