Grenades were found in a school yard:
http://starbulletin.com/2002/03/30/news/briefs.html 3 live grenades found in Big Isle school garden
WAIMEA, Hawaii >> Army experts have found and removed three live, World War II-era grenades at a garden at Waimea Middle School on the Big Island, the U.S. Army Corps of Engineers announced.
Army contractors used the current spring break to survey the garden. A live grenade was found at the garden on Feb. 5, and the garden was closed.
Besides the three live grenades, contractors located an inert piece of another grenade and seven bullets, all below ground, the corps said. Explosive experts from Pohakuloa Training Area disposed of the live ammunition.
They even tested chemical weapons on civilians here back in the '60s. Tell me there aren't a couple of unexploded sarin nerve agent shells sitting around in the forest for some hiker to trip over:
http://starbulletin.com/2002/10/10/news/story6.html WASHINGTON >> The Pentagon acknowledged yesterday that some soldiers engaged in chemical and biological weapons testing in the 1960s may not have been fully informed about the secret experiments conducted at sea and in five states from Hawaii to Florida. Some tests used the military's deadliest nerve agent, VX.
Thousands of civilians in Hawaii and Alaska also probably were unaware they were sprayed with relatively mild bacteria meant to simulate germ weapons such as anthrax, the Defense Department's top health official said.
Dr. William Winkenwerder, assistant defense secretary for health affairs, said there is no evidence anyone died as a result of the classified tests, which were part of biological and chemical warfare programs the United States abandoned in 1970.
http://deploymentlink.osd.mil/pdfs/pine_ridge.pdf Sarin filled BLU-19/B23 and BZ filled BLU-20/B23 bomblets were detonated in test areas in the upper Waiakea Forest Reserve and in the Olaa Forest Preserve, southwestof Hilo, on the island of Hawaii in May and June 1966.