Gerald Casaday, USN retired and stationed at Adak 23 months in 1974-1975, offers the following advice regarding visits to Adak Island:

The information from your member about possible anchorages and hiking opportunities on Adak was missing one vital thing, a caution to potential members regarding Adak 's hazardous materials.

Internet-based research will show that at least 76,800 acres of northern Adak Island were in the hands of the U.S. military from 1942 to about 1997, and mostly fall within a 'Superfund ' NPL (National Priorities List) site, because of the extensive pollution by solid and liquid wastes, and by unexploded ordnance, some from storage, some fired on weapons ranges, some discarded and some jettisoned by aircraft suffering in-flight emergencies. Additionally, anti-personnel mines and metal impalement hazards ( 'Rommel Stakes ') still exist in some places by the many thousands, and have been written off as unrecoverable.

Your forum readers need to be advised that fish and shellfish in some areas are still considered as risky, and that they should exercise 'due diligence ' by doing thorough research of this area before visiting.

Sincere thanks,
Gerald Casaday

I propose to head up that way next summer (though not as far as Adak), so I 've been doing some research.
I found this:
http://www.atsdr.cdc.gov/HAC/PHA/adak/ada_p1.html
which indicates that the risk from ordnance is "extremely low" and there is "no public health hazard" in the local fish and shellfish. But it would be wise to go into Sweepers Cove and get up to date information from the officials on the spot.

By the way, the RCC Pilotage Foundation has a good PDF pilot on the Aleutian Islands chain here:
http://www.rccpf.org.uk/ppgs/arctic/Aleutians%20&%20Alaska.pdf