This is a preliminary survey of coal mines that is an initial estimate of inundation potential at specific mines. This survey was done in order to better direct MSHA's investigation of potential inundation hazards in response to the Quecreek incident. This inundation potential survey has been quoted several times in public meetings that addressed inundations. This information has been the subject of several recent FOIAs.
Inundation Potential Categories
Category A - This category includes mines where other known workings are within 500 feet of mining being done in the same seam, or within 100 feet of working above or below the subject mine.
Category B - This category includes mines where other known workings are more than 500 feet, but less than 1000 feet from mining being done in the same seam and more than 100 feet from workings above or below the subject mine.
Category C- This category includes mines where there are no known workings within 1000 feet of the subject mine.
• See Chart
Note: These are preliminary classifications based primarily on 30 CFR 75.372(b) old works map locations. Actual inundation potential is influenced by many other factors, including: availability of old maps, depth, seam dip, storage capacity of abandoned workings, water levels, accuracy of maps, post-final map mining, accuracy of surveying, drilling in advance of mining, pumping water out of abandoned mines, etc. In no way should these preliminary classifications be used to address the absolute inundation potential at these mines. These classifications were developed to initially direct MSHA's inspections and investigations for inundation prevention. If there are questions about a specific mine, please contact the appropriate District Manager for more recent information. If you have information on abandoned mines that may be potential inundation hazards, please call the inundation hotline (1-800-746-1553) and leave a message