Florence in Florence County, South Carolina — The American South (South Atlantic)
Atomic Bomb Accident at Mars Bluﬀ, March 11, 1958
In 1958, in the midst of the Cold War, the U.S. Air Force accidentally dropped an atomic bomb near here. The unarmed 7,600-lb., 10'8"-long bomb was aboard a B-47E bomber on a training mission headed for England. Its high-explosive trigger detonated on impact, making a crater as large as 35 feet deep and 70 feet wide.
The bomb landed in the woods behind the asbestos-shingle sided home of railroad conductor Walter “Bill” Gregg (b.1921). Gregg, his wife, their three children, and a niece were injured by the concussion, which destroyed the house and out-buildings and did slight damage to buildings within a 5-mile radius.
Erected 2008 by The Florence City and County Historical Commission. (Marker Number 21-26.)
Location. 34° 11.801′ N, 79° 39.796′ W. Marker is in Florence, South Carolina, in Florence County. Marker is at the intersection of East Palmetto Street (U.S. 76) and University Road, on the right when traveling west on East Palmetto Street. Touch for map. Marker is in this post office area: Florence SC 29506, United States of America.
Other nearby markers. At least 8 other markers are within 4 miles of this marker, measured as the crow flies. Francis Marion Memorial Highway (approx. 0.7 miles away); Hewn-Timber Cabins (approx. ¾ mile away); American Legion Post #1 / 2nd Lieutenant Fred H. Sexton (approx. 1.6 Mt. Zion Rosenwald School (approx. 1.6 miles away); Mt. Zion Methodist Church (approx. 1.6 miles away); Red Doe (approx. 1.7 miles away); William R. Johnson House / The Columns (approx. 2.3 miles away); Jamestown (approx. 3.2 miles away). Touch for a list and map of all markers in Florence.
Also see . . .
1. Man Recalls Day Nuclear Bomb Fell in his Yard. Article based on an interview with Walter Gregg. (Submitted on October 25, 2009, by Craig Swain of Leesburg, Virginia.)
2. Mars Bluff "Broken Arrow". Detailed account of the accident. Note the news reel footage video at the bottom which includes views of the house and damage to property. (Submitted on October 25, 2009, by Craig Swain of Leesburg, Virginia.)
3. Mars Bluff Impact Crater. According to this article, the crater is slightly northeast of the marker location, off Lucius Circle. (Submitted on October 25, 2009, by Craig Swain of Leesburg, Virginia.)
4. Columbia Star article. Article on atomic bomb accident at Mars Bluff. It also contains photos of the site not long after the accident. (Submitted on November 11, 2009, by Michael Sean Nix of Spartanburg, South Carolina.)
1. Controlling Access to the Site
I am originally from Dillon, SC. On 11 Mar 1958,
One of our biggest concerns was having unauthorized individuals attempting to gain access to the site. We were forewarned by guys in black suits about those who would attempt to gain entry. There were two of us guards posted at the road going to the house and area where the explosion took place. We worked 12 hours shifts and ate C rations. Only certain individuals were allowed to enter the area, however, we did have attempts by those not authorized. We detained them and turned them over to the guys in the black suits. Don’t know what became of them.
A special crew came in to remove any remains of the bomb, its components and any other material which was considered to be Air Force property. I was there for about a week or so until the situation was under control, all property had been removed and the state troopers took control once again. We departed from the Florence airport on a C-119 aircraft and flew back to Hunter AFB. All of the images are clear in my mind as if it happened yesterday. I did visit the house, workshop and huge hole in the
— Submitted December 3, 2011, by Chuck Norton of Hawkinsville, Georgia.
I was the Commanding Officer of the 48th Ordnance Detachment (EOD) at Fort Jackson, SC when the bomb fell. It was our duty to go to Florence and be the first to approach the pit to be sure there was no radiation and/or explosive hazard. I was the first man to crawl across that crater, twice, with appropriate meters in my hand and certified that there was no radiation hazard. The incident was "classified" at the time and I was unable to talk about it for about 30 years. It is good now to read the Air Force version for once we were finished in Florence we returned to Columbia and never said any more about the incident.
— Submitted April 30, 2015, by William S. Fiske of New Bern, North Carolina.
Categories. • Notable Events • War, Cold •
Credits. This page was last revised on August 14, 2017. This page originally submitted on October 25, 2009, by Stanley and Terrie Howard of Greer, South Carolina. This page has been viewed 32,349 times since then and 6 times this year. This page was the Marker of the Week March 25, 2012. Photos: 1, 2, 3. submitted on October 25, 2009, by Stanley and Terrie Howard of Greer, South Carolina. 4, 5, 6. submitted on May 10, 2011, by PaulwC3 of Northern, Virginia. 7, 8. submitted on May 12, 2014, by David Taylor of Darlington, South Carolina. 9. submitted on July 27, 2014, by Brian J. Scott of Spartanburg, South Carolina. • Craig Swain was the editor who published this page.