News Five Investigates: Oil Hiding In Sand

News Five continues to test water and sand along the Gulf Coast, looking for oil the eye can't see.

On Thursday, we collected a second round of samples from Gulf Shores and Orange Beach, and for the first time, we've collected samples from Perdido Key, Florida and a favorite fishing spot just off the Causeway in Mobile Bay.

We delivered the samples to Bob Naman, a local chemist with nearly 30 years of experience on the Gulf Coast.

Naman, who told us water and sand on the Gulf should contain no more than 5 parts per million (ppm) of oil, tested our water samples for oil and grease and our sand samples for total petroleum hydrocarbons.

According to the tests, our water samples taken near the shoreline of Mobile Bay and from Perdido Key were clean with less than one ppm of oil.

Water collected from Orange Beach and Gulf Shores were also significantly cleaner than we tested the water two weeks ago. Orange Beach contained only 2 ppm of oil, while Gulf Shores contained 12 ppm.

But, it didn't take long for us to discover where the oil is hiding. Hidden in the sand, we found oil concentrations as high as 281 ppm.

To see the results of our tests watch the full story in the video box on the right.