Desdemona suspected that it was natural tidal action, and not a BP cover-up, that buried the oil under a new layer of sand; we saw something similar on Pensacola Beach. But the Save Our Shores Florida folks claim that Sheriff’s deputies confirm BP hauled in the sand:

The sand covering most of the beach was of a much different consistency from the beach closer to the water (very gritty and filled with broken shells). There were lots of piles of sand dumped on the beach as well as the sand covering everything else. After shooting this video, two local deputies, who came to escort us off the beach, confirmed that BP had been trucking in sand to the beach and smoothing it over. The bottom layer of sand is very tarry in some places and very thick and hard in others. The degraded oil is forming a hard layer a few inches under the dumped sand.

Sand dumped over degraded oil on LA beaches