Management of Commercially Generated Radioactive Waste - U.S. ...

Draft p. 3.6.8, 9
Issue
367
ALTERNATIVE DISPOSAL CONCEPTS
The Emplacement Section (3.6.2.4) is incomplete and inaccurate.
* The implication is that any drillship or trenching concept would require a second ship
and that no technology is known for doing both hole drilling and emplacement from one
ship. Drillships can certainly do both.
* The section also implies that the penetrometer is simple and accurate. Such is not
the case. It could act like an unguided glider slipping its way down into the sea-
bed. It may soft-land, ricochet off the bottom, or enter at an angle. As a result,
its position may not be known, it may not be retrievable, and it can not be considered
an accurate, simple way to emplace wastes.
The retrievability discussion (3.6.2.6) is misleading. It implies that the penetrome-
ter is easiest, and hole-drilling, the hardest. As a matter of fact, GLOMAR CHALLENGER has
demonstrated time and again in the Deep Sea Drilling Program of the National Science Foun-
dation the ability to reenter a drill hole of about 18" in diameter at a depth of 10,000
feet. On the other hand, retrieval of penetrometer emplaced items has not been accomplished
in situ.
Ocean Transportation (Section 3.6.4.5) needs more thought.. The docking facility, not
described, is supposed to be able to handle three ships, each operating on a schedule of
four trips per year. Given the realities of dock utilization, it allows each ship only
about ten days per trip at the dock. There will be a lot of times when a second ship will
be waiting at anchorage for dock space. This seems a bad idea for ships handling this kind
of material and performing such specialized tasks. (124)
Response
Drillships can certainly be used both for transport, drilling, and emplacement. But
it would not be efficient to use a drillship for transport, in which most of its time is
spent going to and from the dock facility.
The penetrometer is not a "glider", making soft landings or ricocheting off the bot-
tom. With a nose and tail fitted, it is guided into the bottom at a predetermined location
and to a predetermined depth. Its position would be known from its time of release until
it came to rest because it would be tracked by a transponder array on the bottom. Further-
more, present technology allows accurate position determination.
There is no implication that the penetrometer is easiest and drilling the hardest: it
is stated that the penetrometer is cheapest, and drilling the most expensive. Both are
established facts, having been demonstrated with scale models in the deep ocean. The only
remaining questions relate to the size of a penetrometer that can handle the waste, or the
size of the drill that can make a hole big enough to hold a canister one foot in diameter.