Most large scrapyards are now using drive-through scintillation detectors, similar to is used by DHS in many ports and container yards. These systems are very sensitive, and for good reason -- the cost to decontaminate a facility is huge. Most radioactive sources that end up in the waste stream are small -- a Cobalt-60 radiography source is about the size of a hockey puck, and encased in a lead shielding container the size of a small ice chest. Yet the radiation from this source (if the shielding is damaged) can cause severe burns, death with seemingly short exposure, and could contaminate thousands of tons of steel if ground up or melted down.
I will echo the advice given by two prior posters -- don't waste money on a CD Geiger counter, and tell your friend to get his scrap elsewhere. If he's running a business, he should invest in a Radcomm RC2 or similar scintillation counter (a more sensitive type of Geiger counter, cost is around $1000), find out where the radiation is coming from, and consider calling the EPA.
It's not something to be trifled with. Even low-level contamination (i.e., a source you'd have to hold against your junk for ten years to shoot blanks) can have staggering cleanup/decontamination costs. And the high-level waste can give you a lethal dose in mere minutes. You feel a bit of a tingle, you taste something metallic in your mouth, and three days later you're dead.
sure they did not mean "stolen"?