The earliest recorded coal discovery in the State of Washington was made in 1833 near the junction of the Cowlitz and Toutle rivers (1).
Coal mining primarily occurred within the north-central part of Cowlitz County. Mine hazard areas are those areas underlain by or affected by mine workings such as adits, gangways, tunnels, drifts, or airshafts, and those areas of probably sink holes, gas releases, or subsidence due to mine workings. Locations of mine hazard areas may be known or unknown, based on best available information.
(1) Culver, Harold E., The coal fields of southwestern Washington: Washington Geol. Survey Bull. 19, p. 16, 1919.