Beyond that there is the possibility that the mining itself may be rejuvenated, not for iron but the associated manganese, a strategic mineral involved in the manufacture of steel. Some years ago Dr. Eric Force of the U.S. Geological Survey conducted feasibility studies of manganese mining. Although at the time it was deemed to be unprofitable, future markets may change that assessment (E. Force, personal commun., 1995).

At least as real as the positive potential side of the future iron ore story is the downside. Most of the old mine sites are seriously threatened. This is a problem world-wide. As time passes, ground-water seepage fills the old pits and vegetation covers the sites (Fig. 12). With increasing population pressure these sites are seen as potential drowning hazards and attractive nuisances; the general municipal response is to fill and level the old sites. This has an even greater appeal because of the shortage of landfill space (Anonymous, 1967). The result is that many old historic and scientifically valuable sites have already been lost and all soon will be if the trend continues. The history of Maryland's sedimentary iron ores is intimately tied to our state, national, scientific, and cultural history, and we should give serious thought to preserving it.

Figure 12.— Old iron ore pit, probably Duvall's (Singewald No. 234) south of Muirkirk Road at Ellington Drive now overgrown and water-filled, September 1995.