Initial reports from the Big Island, at least, are not worrisome: The air in the vicinity of Pohakuloa Training Area appears to have normal levels of radiation. For those of us who can't fathom the actual reading — 3 to 8 microroentgens per hour — the state Health Department's assurances that this is "normal" should ease the fears in communities downwind of the training area.

It's a start, but these reports don't negate the need for more and better information.

Public concern about environmental radiation exposure stems from the possibility that depleted uranium from military munitions may persist, at that and other military training facilities.

The radioactive materials come from tail assemblies from aiming rounds used in the 1960s. Depleted uranium is what remains after enriched uranium has been removed for use in nuclear reactors, and its high density makes it ideal armor-penetrating ordnance. It vaporizes on impact, leaving compounds in gas and particle form, hazardous if breathed or otherwise internalized.

The trouble is, the residue may be airborne only in the initial explosion, and then whenever the soil is kicked up and carried on the wind. Even with the most sensitive testing of the air, the risk factor may register only intermittently.

That's why Dr. Lorrin Pang, a Maui County state health official, who has spoken out as a private citizen, has pointed out the need for soil tests to build a database with any consistency.

He's right: Soil sampling should be part of follow-up surveys by the state. Legislation seeking something similar, HB 1452, did not pass but signaled a broad public concern about the issue.

The Army has committed to doing further surveys this summer, at Schofield and Makua as well as Pohakuloa. While details are still sketchy, an Army spokesman has said the air will be tested, and "additional soil and water samples will be collected and sent for laboratory analysis as required."

Let's hope the military is liberal in calling for soil and water tests. Although the level of risk has not been established, it's fair for the host community to expect a thorough examination. The need to dispel any concern about the safety of the public, as well as our soldiers, is paramount.