Both stripped overburden and underground mine wastes were indiscriminantly dumped over large areas surrounding mining operations. The elongate one is a lake. It is hard to find in the 1972 image. This long lake is the Deer Creek Lake, formed by damming the creek of the same name. In the 1972 image, it was just beginning to fill with back-up water, so that it was then almost roundish.
C is anthracite waste.
The features at I, J, and K are large areas of defoliated forests on the ridges, thus the ground controls the reduced reflectance compared with the bright toned healthy trees. The year 1973 saw a major infestation of the leaf-eating Gypsy Moth. Areas from New England to the Carolinas were affected. Pennsylvania was especially hard hit. The PA State Dept. of Environmental Management was able to use Landsat imagery to delineate areas hard hit and to identify areas in need of spraying.