Union County Historical Production Figures |
| YEAR | SURFACE | UNDERGROUND | TOTAL |
| 1949 | 67,622 | 684,948 | 752,570 |
| 1950 | 113,138 | 625,413 | 738,551 |
| 1956 | 30,000 | 2,260,682 | 2,290,682 |
| 1957 | 6,300 | 2,901,446 | 2,907,746 |
| 1958 | 3,997 | 2,080,241 | 2,084,238 |
| 1959 | 83,344 | 2,657,706 | 2,741,050 |
| 1960 | 82,581 | 2,742,097 | 2,824,678 |
| 1963 | 158,397 | 3,051,040 | 3,209,437 |
| 1964 | 444,398 | 3,500,688 | 3,945,086 |
| 1965 | 427,761 | 4,133,117 | 4,560,878 |
| 1966 | 412,667 | 4,677,780 | 5,090,447 |
| 1967 | 106,375 | 4,437,816 | 4,544,191 |
| 1978 | 12,214 | 4,786,543 | 4,798,757 |
| 1979 | 179,418 | 5,666,057 | 5,845,475 |
| 1980 | 113,811 | 6,262,433 | 6,376,244 |
| 1981 | 70,068 | 5,779,492 | 5,849,560 |
| 1982 | 62,104 | 6,258,553 | 6,320,657 |
| 1983 | 68,707 | 4,490,685 | 4,559,392 |
| 1984 | 88,279 | 5,930,718 | 6,018,997 |
| 1985 | 17,898 | 5,584,309 | 5,602,207 |
| 1987 | 69,541 | 8,658,334 | 8,727,875 |
| 1988 | 74,842 | 7,119,513 | 7,194,355 |
| 1989 | 117,651 | 7,404,591 | 7,522,242 |
| 1990 | 34,772 | 9,147,064 | 9,181,836 |
| 1991 | 319,393 | 7,421,174 | 7,740,567 |
| 1992 | 477,333 | 7,232,067 | 7,709,400 |
| 1993 | 328,606 | 3,840,985 | 4,169,591 |
| *NOTE: Source: |