and spent weeks raking fuel from area beaches. signs of disaster can still be found in the delicate marshes. >> it's there. it hasn't gone away. the bacteria haven't consumed the oil. >> reporter: after taking several core sediment samples, the unmistakable scent of oil remains. that is distinctive. you can really smell it there. >> now you see science, sometimes we have to search. but this is definitely tainted with oil. >> some areas remain close to shell fishing and those who oyster for a living say they feel for the counterparts in the south whose fishing grounds are being devastated by the b.p. spill. >> if the water is not clean, they are not going to grow. they are going to die. >> in the decades since oil decimated the marsh lands, the area has largely recovered. but it's what lurks beneath the seemingly idyllic spot that speaks volumes about the long road ahead for gulf coast residents. in falmouth, massachusetts,