Pine Point is a popular spot for those on the water but I know a rider named Tom used to at least ride buggys there in the past.
You may want to go to
www.powerlinesports.com and post the question there as that site is heavy with MA / NH riders and they will be familiar with the spots in ME.
Ogunquit Beach is an option at low tide too but only outside of the protected / lifeguarded section.
Depower Quiver: 14m Gin Eskimo, 10m Gin Eskimo III, 6m Gin Yeti, 4.5m Gin Yeti (custom bridle and mixer)
Fixed Bridle Quiver: MAC Bego 400, JOJO ET Instinct 2.5 & 5.5, Lil Devil 1.5, Sting 1.2
Rides: Ground Industries