UNEP's report on the Lebanon says they have found no Uranium. UNEP says:

The choice of instruments used in the environmental assessment in Lebanon was driven by UNEP’s in-depth experience of such equipment in past DU missions in the Balkans and the joint IAEA/UNEP mission to Kuwait. Thanks to their high sensitivity, effective sound alarm, durability, and robustness, these instruments have proven ideal for such missions.

The problem with this smugness is that in the Balkans and Kuwait UNEP was looking for Uranium from armour piercing shells; in Lebanon the situation was quite different.
When Uranium shells don't hit hard targets, the Uranium doesn't burn and the penetrator can remain entire. Iraqi children have been known to keep them as playthings and Dr. Gunter Horst — an early anti-DU campaigner — picked one up in Iraq. When he landed back home in Germany it set off alarms at the airport and he was arrested, much to his surprise and consternation. Even those shells that do hit hard targets leave some shrapnel. This was what UNEP is used to dealing with, and since fighter planes have on-board cameras to photograph their missions they even had some records to tell them where to look.
In the Lebanon the situation is different. It was a bombing campaign in the course of which it became apparent that there was Uranium in the bombs. In contrast to artillery shells probably all of the Uranium burnt. UNEP was told this in August, so they knew what they were supposed to be looking for. Unfortunately they have an appalling track record of looking for Uranium dust (see this criticism of their Kosovo mission 1999-2000.

The UNEP report lists the instruments used in the Lebanon survey. All are unsuitable for finding Uranium dust. Only one is capable of finding WDU in the low concentrations likely to result from using Uranium weapons, but it would require the operator to go at snail's pace on hands and knees.

The Saphymo-SRAT S.P.P.2 NF scintillometer is a gamma detector. The only gamma signal from Uranium is a weak emission (at 185 KeV) from U-235. It wouldn't detect Uranium in the field unless the operator was standing on top of a large deposit.
In a laboratory experiment the more sensitive instrument we use at LLRC failed to pick up Uranium in a soil sample known to be contaminated with 200 Bq/Kg of WDU.

The Automess Dose Rate Meter AD 6 and its Alpha-Beta-Gamma Probe AD-17 is a bit of a mystery, as we couldn't find a technical spec for it. However, UNEP says it was only used for measuring background gamma rates, so it isn't relevant.

The Fieldspec Instrument identiFINDER-N/He-3 is another gamma detector, so it's no use for Uranium.

The Inspector instrument is manufactured by S.E. International Inc. is the one potentially useful instrument. It's a small hand-held field Geiger Counter which can detect beta particles, so it could in theory pick up the betas from the two daughter isotopes of Uranium — Protactinium-234m and Thorium-234.
But there are problems. Being small, it has a small window (16 sq.cm). Secondly, it has low sensitivity to beta rays, so the instrument would have to be held close to the ground (about 10 cm). The Inspector compensates for its low sensitivity by displaying a 30 second moving average. This means the operator would have to crawl across the ground surface slowly enough to let the detector scan each tiny patch of ground for 30 seconds. It would take a long time to cover a small area. In principle this may be the best that UNEP could accomplish with the instruments it used.

As we have said before, finding Weapons-derived Uranium (WDU) is not easy. LLRC succeeds (for instance in Lebanon) by combining knowledge of physics with appropriate instrumentation which cost us some thousands of pounds. Any nuclear site has even better equipment and there is no excuse for UNEP not to use what is standard in the industry. The inevitable conclusion is that UNEP is incompetent, or that those officials who trained, equipped and directed the team intended it to find no Uranium.

Looking properly: Chris Busby in Iraq with a scintillation counter

Click here for Green Audit report on UNEP's instruments.
Click here for the next episode -- our January 2007 report on UNEP's findings.