how many coatings af Anchorseal to apply?

Marv One coat is fine if it is put on heavy with a brush. Spraying will likely need two coats a day apart. If it is going to sit a long time in sunlight, two coats are recommended but I tend to use only one with decent results.

Like Marvin says, one heavy coat is enough. Keep applying until it stops soaking in. If I later cut the long into pieces and slabs I'll recoat so any places it was scraped off are good againg.