Wartime Past To Bring Peacetime Danger?
Bombing Run: 1-Initial Point; 2-Target Location; 3-Egress; 4-JTAC Team
“MOJO-2 this is HAMMERHEAD-17.
Control Type 1.
COWBOY, 5 right, nine kilometers.
920, 80 by 50 two-story building, 438 216.
No mark, southeast 1,100 blue smoke, egress northeast to BLUNDERBUSS.
MOJO-2 CLEARED HOT.”
Dear Reader, you just called in a Close Air Support (CAS) strike on what is currently Santa Margarita Toyota. Congratulations on your first “9-line” radio transmission as a Joint Terminal Attack Controller (JTAC) – unless you are in the military and do this regularly, in which case: thank you for your service and please let us know how our skills are.
Alright, bizarre, potentially inappropriate opening but you got my attention; what’s this article about? Rancho Santa Margarita has an unknown volume of practice ordnance and explosive waste (OEW) scattered throughout the community, pending ongoing clean-up effort completion in 2033.
By Arrow Santos
Explosive waste is moved into piles during the original removal phase as part of the construction process for the master-planned community of Rancho Santa Margarita
Blasts From The Past
What we know today as the bustling community of Rancho Santa Margarita was formally Trabuco Bombing Range from 1944 to 1955. Established during World War II and operational through the ending of the Korean War, literal tons of various practice munitions were expended on the land. This training ground was used by pilots from the nearby Marine Corps Air Stations (MCAS) El Toro. Converted from open farmland, over 1,800 acres were seized via eminent domain after the Secretary of the Navy determined the “immediate and exclusive possession of said property is vital to the successful prosecution” of WWII. About a year later a deal was struck for the original owner (the famed O’Neill family of Rancho Mission Viejo company) to regain possession of the land and lease it back to the Government. This agreement stayed in place until the range was decommissioned. The land was then reverted back to farm and grazing land until construction of the Rancho Santa Margarita Planned Community began in the mid-1980s.
“These military munitions may pose an explosive hazard to you.”
Aerial photo of Rancho Santa Margarita community (1992). X = 8th hole of golf course. O = Adobe hut.
Remaining, Removed, Resident – Don’t Chunk The 8th Hole
Over the years there have been ongoing efforts to remove and neutralize OEW in the area. During the initial development of the community in 1984, the Orange County Hazardous Device Squad (OCHDS) and Marine’s Joint Explosive Ordnance Disposal Unit (JEODU) removed 14 dump truck loads of ordnance in just two weeks! The Rancho Mission Viejo company then requested the Base perform a sub-surface sweep of the affected acres in hopes of removing all remaining items. The problem was a bit bigger than a couple of weeks of cleanup. After review, the military concluded that should every then-available detection device on the West Coast be committed to this single project, it would take seven years to complete and only result in a 32% removal certification. The current timeline now sits at an expected completion date of 2033 with an estimated cost of $11.7 million still outstanding. The Department of Defense shows that over $2.6 million has been spent on cleanup and evaluation so far. Apparently dropping bombs is much easier than picking them back up.
As construction progressed on Orange County’s 33rd city, the munitions piled up faster than any agency could dispose of them. The decision was made by the development company to ultimately bury several tons of OEW under the fairway on the 8th hole at the Tijeras Creek Golf Course! Maybe it’s best to save the hole-in-one attempts for the back nine. This unusual solution was implemented during the grading phase of the master-planned community, ensuring the weapons waste was placed 20-30ft beneath the surface. In 1993, the Army Corps of Engineers cited two key reasons this unexpected location was chosen:
Future building construction was improbable compared to other vacant zones that would one-day host commercial or residential projects (which has proven true now that we are in 2020).
Should an emergence or other resurfacing occur at this site, it would allow for immediate recognition and mitigation due to the open nature and dispersed usage of the space.
This might not be the place of choice for a pogo stick competition, but no injuries or deaths have ever been reported relating to materials recovered in Rancho Santa Margarita.
Various munitions are displayed side-by-side after being recovered in Rancho Santa Margarita
Practice Yet Perilous
Several types of practice ammunition were released on the range – including 3-pound, 4-pound, and 25-pound (Mark 76) practice bombs and 2.25-inch, 3.5-inch, and 5-inch practice rockets. “The practice bombs contained an expelling charge of smokeless powder and a marker load of stabilized red phosphorous or zinc oxide, while the practice rockets were completely inert,” Colonel Wayne Scholl, Corps of Engineers Chief, wrote in a report on items recovered. The firing mechanism used in many models for marking where the practice bombs landed is further explained as consisting of “a long 10-gage blank shotgun shell 5.75 inches long containing an ejection charge and a pyrotechnic charge which burns above water after impact, forming a large puff of white smoke.”
Don’t let a dummy bomb make a dummy out of you. Then-Commanding Gen. D.V. Shuter, of MCAS El Toro, lamented in an official request letter to the Army Corps of Engineers, “Local newspapers did print articles … which referred to the existence of practice bombs in and around Rancho Santa Margarita. Unfortunately, the information contained in the article was somewhat misleading in that it minimized the potential danger of the ordnance.”
Practice Bomb Assembly & Cutaway Diagram - RSM Bombing Range
Safe Flying
At the beginning of 2020, one of our clients (who owns an industrial property on Avenida Empresa) received a letter from the Department of the Army about these matters. It reads in part, “Available information indicates military munitions may be present on or near your property as a result of past munitions-related activities that Department of Defense conducted on this Formerly Used Defense Sites property. More specific information is enclosed. Should military munitions remain on this Formerly Used Defense Sites property, they are most likely below the ground surface; however, there is a possibility that some may have become partially or fully exposed. If present, these military munitions may pose an explosive hazard to you, your family, other property users, or the public. The Army recommends you share the enclosed information with those who use your property, including those who lease or rent your property. To protect yourself, your family, and other property users, please review the enclosed explosive safety education materials, be aware of the potential hazards present, and follow the 3Rs of explosive safety: Recognize when you may have come across a munition, and that munitions are dangerous; Retreat, do not approach, touch, move or disturb it, but carefully leave the area; and Report call 911 and advise the police of what you saw and where you saw it. Local law enforcement will arrange for Department of Defense Explosive Ordnance Disposal or police bomb squad personnel to remove and destroy it.”
Again, while the risk may appear minimal (or non-existent) it’s always better to play it safe should you discover anything resembling a freedom present from decades past.
Did you know our South Orange County backyards had such an explosive history? If you have received a similar letter this year or knew someone who flew practice sorties on the Trabuco Bombing Range: we want to hear from you! Send an email to contact@wynnecre.com or leave a comment below.
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Safe flying MOJO-2; HAMMERHEAD-17 out.