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SAND FOE MINE FLUSHING.
and has an estimated tonnage of about 5,000,000 tons. The material contains about 50 per cent of sand, with gravel, bowlders of hard rock, and very little clay.
One of the most desirable bodies of sandy till is on the estate of William Miles, just west of Olyphant. The land is not built on and is adjacent to various lines of railroads. A moderate amount of water is available for sluicing in a near-by creek, and water possibly can be had from the river also. The till area measures about 2,000 by 1,500 feet, and the thickness of material available is about 30 feet. These measurements indicate an aggregate of nearly 5,000,000 tons. The proportion of sand is variable, but in places it exceeds 60 per cent. It is being dug to a small extent for sand for local building purposes. There is not sufficient clay in any part of the area to be disadvantageous, and the gravel and bowlders could be crushed, if desired.
ALLUVIUM.
Along the Lackawanna River extend low alluvial terraces, which are underlain by sand that in greater part contains only a small proportion of coarse material. Unfortunately, however, the sand area near Scranton is covered with houses or is held for its value as building lots, so that the sand is not available except at a few points. As the terraces are very low, the tonnage of sand that could be obtained is not great. It is possible that the water of the river could be used for sluicing this material, hut because of the great variation in the amount of water available during the different seasons of the year, the conditions are not altogether favorable. The location of the railroads along the river complicates the problem of removing the sand. Doubtless this source of material would not be as advantageous as the sandy till or crushed rock.
RIVER SAND.
The most extensive deposit of sand in the northern anthracite coal basin is under the deep valley of the Susquehanna River from Pittston to Nanticoke. Its width averages 2 miles for a long distance and its thickness varies from 100 to 200 feet in greater part. There are many places where this material could be lifted from the river channel by dredges and loaded on empty coal cars. In the river and harbor work of the United States Engineers office and in Panama Canal excavations sand is dredged from depths of 20 to 40 feet and carried in pipes 1,000 to 2,000 feet at a cost of 3 to 5 cents a cubic yard. The cost of handling sand from the Susquehanna River is a matter for local engineers to determine. The sediment brought down by the river, especially in tune of flood, would rapidly refill excavations made by dredging.