Hanna Basin Museum
  • Museum
    • 2020 Carbon Cemetery Association and Hanna Basin Historical Society ​Spring Newsletter
    • 2019: Hanna Basin Historical Society and Carbon Cemetery Association Newsletter
    • Visitors to the Museum
    • Books and Magazines to Read Online about the Hanna Basin
    • Books Available for Purchase at the Hanna Basin Museum
    • Order Form for Materials Available for Purchase at the Museum
    • Membership and Support
    • Links to Other Wyoming Museums >
      • Medicine Bow, Wyoming, Museum and Hanna Basin Neighbor
      • Rock Springs, Wyoming, Historical Museum
    • Copyright Infringement Notification
  • Carbon
    • Hanna Basin Museum - Time Line
    • CARBON CEMETERY RECORDS
    • Carbon Mine Fatality Records
    • Visitors to the Carbon Cemetery
    • Carbon - Wings of Imagination - A Letter From Old Carbon
    • Carbon - A Poem by Mrs. C. E. Ellis
    • 2003: Carbon Cemetery Restoration
    • 2011: Carbon, Carbon County, Cemetery Restoration 2011
    • 2011: Bow River FFA Community Service Project: Carbon Cemetery
    • 2014: The Carbon Cemetery
    • 2015: The Old Carbon Cemetery Privy
  • Hanna
    • HANNA HAPPENINGS
    • THE HANNA CEMETERY: From the Bottom of the Mine
    • HANNA CEMETERY RECORDS
    • Hanna Burial Plots and Lots >
      • Hanna Blocks and Lots 1 - 6
      • Hanna Plots 1 - 50
      • Hanna Plots 51 - 80
      • Hanna Plots 81 - 129
      • Hanna Plots 130 - 175
      • Hanna Plots 176 - 209
      • Hanna Plots 210 - 298
      • Hanna Plots 299 - 349
      • Hanna Plots 350 - 379
      • Hanna Plots 380 - 419
      • Hanna Plots 420 - 500
    • Hanna Early Churches >
      • Introduction to Hanna’s Early Churches
      • Episcopal Church - History, Bell and Cross
      • Methodist Church - Organ
      • Colored Baptist Church
    • Hanna Military in the Hanna Cemetery >
      • Hanna Cemetery - In The Military
      • Arthurs, Peter Killed in Action World War I
      • Love, Michael V. Killed In The Line Of Duty
      • Jones, William D. Died of Wounds Received In Action World War I
      • Lucas, Bernard R. Killed In Action World War II
      • Lucas, William C. Died of Wounds Recieved In Action World War II
      • Luoma, Arvo A. Killed in Action World War II
      • McAtee, William J. Killed in Action Vietnam
      • Saari, John Killed in Action World War II
    • Hanna Cemetery - Japanese Monuments Transcribed
    • Grave Headstones for Hanna Miner Fatalities Buried Elsewhere than Hanna
    • Hanna Where Did They Come From?
  • The People
  • Schools
  • Coal Mines
    • A History of the Hanna Coal Miner from 1868 to 2017: Bob Leathers' Notebook
    • Hanna Basin Mining Companies and Mines
    • Men Injured in the Hanna Mines
    • 1903 June 30: Explosion of the Union Pacific Coal Company's No. 1 mine in Hanna >
      • Hanna 1903 Explosion Explained
      • List of Miners Killed in the June 30, 1903 Explosion
      • 1904 State Mine Inspector's Report for 1903 Explosion
      • 1903 Explosion Coroner's Inquest
      • 1903 Explosion - Earle Holmes Letter to Wilson Gobble
    • Hanna 1908 Mine Explosions Explained >
      • List of Miners Killed in the March 28, 1908 Explosions
      • 1908 Explosion Coroner's Inquest Report
      • Noah Young's 1908 Hanna Explosion Report to Governor B.B. Brooks
      • 1908 State Coal Mine Inspectors Report - 1908 Hanna Mine Number 1 Explosion
      • David M. Elias - State Mine Inspector Killed in 1908 Explosion
      • 1908 Explosion - Gov. B.B. Brooks Communiations
      • April 3, 1908 Chums From Boyhood Died Side By Side
      • April 16, 1908 U.P. May Not Be Liable
      • 1908: Newspaper Articles from The Wigan Observer in England About the March 28, 1908 Explosion of the Union Pacific Coal Company's No. 1 Mine in Hanna
      • Death of Noah Young - State Mine Inspector for the 1908 Explosion of Mine No. 1
    • 1916 Labor Agreement Between the United Mine Workers of America and the Southern Wyoming Coal Operators
    • 1917 Labor Agreement Between the United Mine Workers of America and the Southern Wyoming Coal Operators
    • 1970 - 1980: Bill Becker's Hanna Strip Mine Blasting Videos
  • Gallery
    • 1889-1912: ​ Elmer Larson - The Butvier Collection from Sally Hafdell and David Eriksson in Sweden
    • Images from Early Hanna Basin and Wyoming
    • Early History of the Union Pacific Railroad
    • 1910-1920: McNulty Family Photo Collection ​Albert Film - Hanna Basin Adventurer
    • 1920 -1930: Gert Milliken's Photo Collection of Unknown Children, Women, Men, and Families in Hanna
    • 1963 October 2: A Large Cattle Drive from Palm Livestock Company at Elk Mountain ​ to Hanna's Union Pacific Railroad Stockyard
    • 2017 April 18: Un​ion Pacific Steam Engine 844 Stopped at Hanna, Wyoming
    • 2019 May 17 and May 4: Big Boy​ 4014 and Engine 844 Were Running the Rails Again
    • Images of Old Carbon Today
  • Notebook

1970 - 1980: Bill Becker's Hanna Strip Mine Blasting Videos

Video and notes from Bill Becker

 The following videos illustrate how 'overburden' was blasted off of a coal seam at an open pit mine. All of the open pit mines in the Hanna area from the early 1970's to the early 1980's used this method, or one very similar to it, to blast overburden.

The process starts with the drilling of a series of large diameter holes (10-12 inch) on a 20 foot triangular pattern. The holes are drilled to the top of the coal seam or in lifts, if the coal was deeper than 100'.  Once the holes are all drilled the powder crew comes in and loads the holes with explosives. These explosives consist of a Class A explosive (i.e. dynamite) and Prell (a ammonium nitrate mixed with diesel). For a hole of 100 foot depth you could easily have 1000 pounds of the Prell in each hole. The loaded holes are then all tied together with PRIMACORD. This cord consists of an explosive called PETN and burns at a rate of about 1 mile per second. Delays are now placed between each of the rows. These delays are on the order of 20-40 milli seconds each. The sequence goes like this: A blasting cap ignites the PRIMACORD which in turn sets off the dynamite which ignites the Prell. Video #3 shows this process to good effect.

The goal of a 'shot' is not just to break up the overburden, but to move as much of the overburden as possible. This is accomplished by initiating the 'shot' by placing the blasting cap at the end of the row closest to the last cut (the open pit).  This area has already been mined and all the coal has been removed. When this first row explodes it throws overburden up and out into the open space of the last cut. The second row, after a short delay, explodes moving more overburden up and out. The process continues with each of the rows exploding successively. At least half of the overburden should be moved by the blast. The other half will be removed by machines (draglines, shovels etc.). 

Drilling and blasting is an expensive process. But not as expensive as mechanically moving overburden. So it is crucial that the 'shot' be effective. As you watch these videos you will see a couple of holes that did not fire correctly for some reason. You can tell by the orange smoke.




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Hanna Basin Museum Website – A Connection To The Past