Evidence of Old Explosives Found in Popular Cave

Sequoia National Park, California workers conducting cleanup and renovation work inside Crystal Cave, a popular tourist attraction, found evidence of old explosives. Workers reported seeing two wires sticking out a broomstick-sized hole that was drilled into a wall of the cave. The wires were attached to a blasting cap, which the workers safely assumed to be live. Upon the discovery of the items, workers and tourists were evacuated from the area and the cave was closed.

An explosives expert for the National Park Service and a cave specialist were called in to investigate the situation. The explosive expert estimated that the wires and attached blasting cap date back to the late 1930s. His estimate was based upon the observation that the wire leads were covered in cloth, not plastic. The last known time that blasting occurred in the area was in 1938.

Two other suspect holes were found during their search. For now, the wire leads and blasting cap have been left in place and the cave closed while authorities devise a plan to deal with the situation. Authorities are concerned that the other end of the blasting cap may be attached to a live stick of nitroglycerin based dynamite. Park officials are hoping that the blasting cap and the potential explosive charges can be safely removed without detonation (unintentional or intentional). However, in the event that a detonation does occur, the plan calls for blast mitigation measures to be installed including blasting mats and blankets to protect nearby delicate cave formations.

Park officials hope to have the explosives removed and cave re-opened by Memorial Day weekend. According to park officials, more than 50,000 people take guided tours through Crystal Cave each summer and fall.