Okay, I am no expert but here is my reasoning behind my comments. As far as I know Great Whites were not in NE waters or extremely rare before the seal colonies on the Cape. I have no interest in diving in waters with great whites. A seal colony at or near Ft W would attract great whites. Also, there are concerns that an established seal colony in NE waters threatens the balance and abundance of shellfish, fish, crabs and lobsters. I share this concern. So while I think it may be interesting seeing a seal while diving, if there was an established colony at FT W, I would likely look to dive elsewhere.
Presuming you're too careful to drive a car, what does it matter?