Updated: Mar 12
You may have received a letter in the mail from the U.S. Army Corps of Engineers regarding potentially discarded or undiscovered practice munitions in the Rancho Santa Margarita area. The letter serves as a valuable reminder that south Orange County’s land has been used for many purposes over the past one hundred years, and that residents should be mindful when hiking, building, or exploring.
From 1944 until approximately 1956, the United States Marine Corp used the southern portion of Plano Trabuco (primarily the present-day Tijeras Creek Golf Club area) as a practice range for aircraft. There were four (4) kinds of practice devices used. One was a “target marker,” which contained a small smoke charge to mark the accuracy of a pilot’s aim. The other three types were practice rockets that did not contain an explosive charge. In 1956 the property reverted to grazing and farmland, and the area was declared a Formerly Used Defense Site.
From time to time, the U.S. Department of Defense may notify residents that munitions may still be found in the area of a Formerly Used Defense Site. The notifications are not meant to cause alarm, but to remind the public to be aware of the land’s history. Though the U.S. Army Corps of Engineers has conducted inspections and munitions removal, it is important that residents are aware of the possibility of finding munitions in the area, particularly after heavy rains, erosion, or major construction.
If you come across a target marker, please keep the following instructions in mind:
Recognize – when you may have come across a munition, and that munitions are dangerous.
Retreat – do not approach, touch, move, or disturb the munition, but instead carefully leave the area.
Report – call 911 and advise the police of what you saw and where you saw it.
The U.S. Army Corps of Engineers is responsible for identifying, investigating, and, when necessary, conducting an appropriate response to address military munitions. Local law enforcement will coordinate with the Department of Defense Explosive Ordnance Disposal crew to properly remove and destroy the munition.
For information about Formerly Used Defense Sites, please visit https://www.usace.army.mil/Missions/Environmental/Formerly-Used-Defense-Sites/ The former Trabuco Bombing Range property identification number is: J09CA020901.