Version history
November 17, 2010
In the text, changed “coal core, surface, and mine samples” to “surface samples and coal core and mine samples” wherever the term appeared.
In table A–1 of appendix A, added data for three new wells.
In table a–2 of appendix A, added the “Sample type” column of data and data for three new surface samples.

September 16, 2011
In table A-1 of appendix A, modified data for three wells.
In table A-2 of appendix A, modified data for three wells.