Utah State University DigitalCommons@USU U.S. Government Documents (Utah Regional Mines and Mineral Resources Depository) 1993 Surface Subsidence Over a Room-and-Pillar Mine in the Western United States United States Department of the Interior, Bureau of Mines Follow this and additional works at: https://digitalcommons.usu.edu/govdocs_mines Part of the Mining Engineering Commons Recommended Citation United States Department of the Interior, Bureau of Mines, "Surface Subsidence Over a Room-and-Pillar Mine in the Western United States" (1993). Mines and Mineral Resources. Paper 3. https://digitalcommons.usu.edu/govdocs_mines/3 This Report is brought to you for free and open access by the U.S. Government Documents (Utah Regional Depository) at DigitalCommons@USU. It has been accepted for inclusion in Mines and Mineral Resources by an authorized administrator of DigitalCommons@USU. For more information, please contact [email protected]. 1. 7 : ' I J '-I '/ IN FORMATION CIRCULAR/ 1993 Surface Subsidence Over a Room­ and-Pillar Mine in the Western United States By Jeff A. Magers M ission: As the Nallon's principal conservation agency. the Department of the Inlerior has respon ­ sibility for most of our nationally-owned public lands and natural and cultural resources. This Includes fostering Wise use of our land and water resources, protecting our fish and wildlife. pre­ serving the environmental and cultural values of our nattonal parks and historical places. and pro­ viding for the enjoyment of life through outdoor recreat,o, . The Department assesses our energy and minerai resources and works to assure that thetr development IS in the best interests of all our people. The Department also promotes the goals of the Take Pride in America campaign by encouraging stewardship and citizen responsibil­ Ity for the public lands and promoting citizen par­ tlclpallon In their care. The Department also has a major responsibility for American Indian reser­ vallon communitIes and for people who live in Island Terntorles under U.S. Administration. United States Department of the Interior Bureau of M ines Information Circular 9347 Surface Subsidence Over a Room­ and-Pillar Mine in the Western United States By Jeff A. Magers Ubrary or CODgnS' CatalogiDg In Publication Data: Mager!, J. ff A. Surf.ce subsidence over a room.and.pillar mine in the westcm United Stah~' / by Jerr A Macers.. p. em. - (Information circular; 9347) Includes bibliopphiCiI rc(crenca (p. 15). 1. Mine lubltdcnce-Colondo-Palis.1de R.cpon. 2. CoIl mines and mining­ Colol"ldo-Palisadc ~pon . I. TIUe. U. Series: Infonnation elmll.r (United States. Buruu of Mines); 9341. TN295.U4 [TN319) 622 s-dc20 [622'.28) 93·2741 CIP UNITED STATES DEPARTMENT OF THE INTERIOR Bruce Babbitt, Secretary BUREAU OF MINES CONTENTS Pog< UNIT OF MEASURE ABBREVIATIONS USED IN THIS REPORT Abstract ........ .......•... •. ..•. • . .. .. • . • . • .... ...•.. • . .. • . • . .. 1 degree min minute Introduction ...............•....•. .... .. .. .. .. • . ... ........ • ....... • ....•... 2 Acknowledgments ... .......•....•. ..•. ....... .• . ...• . .... • . • . • .. ••. •. • . .•..•.•. 2 ft root pet percent Roadside Mine study site .....•... .• . •. ....... .... .• . ..... •.... • .. • .... • ....•..• 2 Site selection .... .... ... .. ......... ... ..... ...... .. ...... ..... 2 in inch Site description .......... • .... • . .. • . ..•... .. ......... • . .•..•....•.. • . ... • 2 Regional geology . .... ... .... ... .. .. .... .. .. ....... ... ... ........ Mine plans .. .... .. .. ...• .. ..•. ...• ... •. .......•... •... .•..•....•.......•....• 4 Northwest section .... ... .. ......... ..... ... .. .. .. .. .. .. .. .. 4 Southwest section ... .... ... .. • ....• ... .• .. ....... • ....•.......• . ......•.......... 5 Third·west section . ... ........ ....... ... .... .... ..... ...... ... ... .... .. 5 Subsidence·mouitoring program ........ .•....• . ...•....•. .... • .... •..• ... .•. ......• . 9 Mooument spacing aDd construction ......... .. ... ... ... .. .. ..... ....... .. 9 Monument locations . • . • . 9 Northwest section . .. .. .. ... .. .................... .. ........... .. ...... .. .... 9 Southwest section. .. .. .. .. .. .. .. .. .. .. .. .. .. .. • .. .. .. .. .. .. .. .. .. .. .. .. 9 Third·west section ..............•.........•. ....... •.. .•. .. •. .. •..• ... .•.. 10 Monitoring procedures and equipment . .. ... ........... .. ...... ............ .. .. 10 Data processing . ........ ..... • . ............ .... .. .• . • . •... ..... ..... .. 10 Subsidence results . ............. .. •. •. ..•. ....... • . •.. • ...•. • . ...... .. ... 11 Northwest section . • . • . • . • . • . • . • . • . • . • . 11 Southwest section . • . • . • . • . • . • . • . • . 11 Third·west section . .. .. .... .. .... .. ..... ........................................ 13 Summary ...............• . ...• . ...• . ... ... ....•. .... ..•... .•.......• .. .. .. • .. 14 Rererences . • . 15 IllUSTRATIONS I. Project location map ... ... .... ....... ..... .......... .. • ....•.......•..... .. 3 2. Roadside Mine study site . .. ... .. .•.. .• . .• ... .•. ... • . ...•.. .... .. .. 4 3. Generalized overburden stratigraphy .. .. .. • ....• . .•....•..•. ... •. •. .. ....•.... 5 4. Detailed overburden stratigraphy ..... ...... ....... ...... ..•.. .. .. .•.... • . 5 5. Northwest section mine plan ... .. ...•. •. • .. •.•.. ...... ..... • ... ...•... ..••... 6 6. Southwest section mine plan ..................................................... .. 7 7. Third·west mine plan .............................. •....•. • . .. • . •.•... • .... 8 8. Total station geodimeter and rencctioD prism assembly . .. .. .. .. .. .. .. .. .... ........ 10 9. Subsidence promes [or northwest section ........ .. .... ...... .... .. .•. ...... • . •.. 11 10. Location of subsidence cracks, northwest section . .. .. ... .. .. .... ..... ...... 12 11. Subsidence aaa.. located over northwest section, 1985 survey . .. ..... .. •. .. .. • ... .. •. ... 12 12 Subsidence aacl< located over northwest section, 1991 survey ...... ....•.. ... •.. •.... 13 13. Subsidence promes [or southwest section ....................• . • .. ... .. • . •.. .. • .• . ••. 13 14. Subsidence promes [or third·west section ... ............ .... ..•....•..•.......•... 13 ,I INTRODUCTION SURFACE SUBSIDENCE OVER A ROOM·AND·PILLAR MINE IN THE WESTERN UNITED STATES The research described in this report as pari of a com­ subsidence research studies is a much more accurate and prehensive eITorl by tbe U.S. Bareau of Mines to develop quantitative understanding of the behavior of subsidence a subsidence data base representative of western U.S. min­ occurring over room-and-pillar and longwall operations in ing conditions. This data base will provide researchers and geologic conditions unique to the West. The ability to mine operators with the information needed to further un­ predict subsidence and associated damage will allow mine derstand the effects of subsidence. This understanding is operators to extract resources that are cWTentiy sterilized needed by mine operators to predict bow mining and geo­ because the technology docs not exist to predict the result­ logic parameters affect tbe magnitude and extent of sub­ ing surface subsidence effects to the degree necessary to sidence in tbe West, thereby 'allowing for a mine design ensure that adverse impacts can be minimized. that will avert or limit the adverse effects of subsidence, This case study was one of several conducted by the In 1m, Congress passed the Surface Mining Control Bureau that together would begin to provide the subsid­ and Reclamation Act. Section 516 (5) (I) of the act re­ ence data necessary to characterize western U.S. mine quires tbe operator to -_adopt measures_to prevent sub­ subsidence. sidence causing material damage_: Therefore, a meth­ Once general subsidence parameters can be estimated, odology to predict subsidence is needed by mine operators the potential impacts of the subsidence can be evaluated. to avoid or mitigate damage resulting from mining. Exten­ ABSTRACT Tbe capability to conduct this type of evaluation will bene­ sive information exists regarding subsidence research in fit mine operators and regulatory agencies that must assess the Appalachian and Illinois coal regions of the United subsidence impacts. This report summarizes tbe results (rom the subsidence research study completed by the U .S. Bureau States (1) ;1 however, information regarding subsidence of Mines at the Roadside Mine, Powderhorn Coal Co., Palisade, co. This research was conducted from research in the West is limited. Western coal mining The major objectives of this study were to (I) present February 1981 to August 1985, with additional data obtained during July 1991 , to evaluate residual sub­ conditions include strong massive sandstone member", measured surface subsidence caused by room-and-pillar sidence. The Bureau studied subsidence at three distinct room-and-pillar sections at separate locations thick and muJtiple coal seams, and extreme variations in mining in the Cameo -B- coal seam; (2) determine the over the mine and determined the maximum subsidence values and surface subsidence proflles for each ove rburden thicknesses, and while research efforts bave timing. rate, and areal extent of subsidence; (3) establish mining section. Maximum subsidence of 3.0 ft occurred over the room-and-pillar sections, with over­ been initiated by the Bureau (2-5), a complete data base the fonal subsidence profiles; (4) correlate mining