UXO - Unexploded Ordinance

by Richard Hannibal

On occasion I hike in the hills behind Chorro Park, adjacent to Camp San Luis and east of Cuesta College. I am well aware of the signs posted in the area that warn of possible unexploded military ordinance. I’m also aware that the areas I hike were used as military training grounds during World War II. It is common sense that some of this ordinance did not explode and lay buried in the ground. I’m confident though, thanks to the years of mine-sweeping cows that graze in the area. They assure me that any unexploded bombs are buried deep in the earth. And yet, I am watchful.

There are danger spots throughout our coastal area. The once named "Baywood Park Training Area" was a 9,145 acre area that now encompasses Montana de Oro State Park, Los Osos, Baywood Park, and parts of Morro Bay, including the sand spit. Like my favorite hiking area, these locations were extensively used for training by the U.S. Army, Marines, and Navy during World War II.

The beaches of Los Osos and Morro Bay were used to practice amphibious assaults in preparation for the Normandy invasion and South Pacific island landings. Everything from small arms ammunition, to hand grenades, to artillery rounds, to demolition charges, and blasting caps were used in these training exercises. The military estimates that about 10% of these munitions did not detonate and remain hidden in the ground.

While the areas have been swept several times for unexploded ordinance (UXO), there is a probability that more remains there yet to be discovered. The weather and natural erosion can uncover and expose these devices, such as this partially exposed shell shown below.

Partially Exposed Shell

As this UXO material rusts and degrades, it becomes more unstable and thus a danger to the public. Some of the materials remain somewhat identifiable, as pictured in the column on the right.

Other UXO material may be more difficult to identify, like the fuze from an explosive shell. The blasting cap in this fuze can easily blow off a hand. This device is quite small; only about 2 ½ to 3 inches in length. In an explosive device or military munitions, a fuze (or fuse) is the part of the device that initiates the function of the bomb.

NEVER TOUCH ANY SUSPECTED EXPLOSIVE DEVICE! Often these devices relied on centrifugal spin to arm the fuze. Sometimes they will detonate simply by being handled or rolled over; as the fuze completes the final required revolution . . . it’s that simple!

These munitions are not only lurking in the ground and sandy areas around Estero Bay, but they also lurk in garages of residential areas. These are the devices that grandpa brought home from the war as souvenirs. If you find anything remotely resembling an explosive device, immediately call 9-1-1 and get everyone away from it. Once the Police and Fire Departments are on scene, they will evacuate the area, establish a safe perimeter, and maintain scene security pending arrival of specially trained and certified bomb technicians.

Recently, two boys found a hand grenade in a field near the Miramar Marine Corps Air Station in San Diego. This area was a former military training area. The hand grenade went off and killed both boys.

This potential danger recently prompted Morro Bay Police Sergeant Manny Silva to put out a training bulletin to all Morro Bay Police Officers and I am passing the information on to you.