Subduction zones and radwaste...

[JPreisig@AOL.COM]

Hmmmmmm.....


       This is from JPreisig@aol.com     .


     Greetings Radsafers.


     I find any attempt to place (reactor???) radwaste in subduction zones

offensive.  I surely don't believe it is the way to go.  There are 

considerable

problems (and errors) in the information being presented in this RADSAFE

string.  Plate tectonic spreading rates in the Pacific Ocean (i.e. the East

Pacific Ridge) are on the order of 6 to 10 cm. per year.  If subduction zone

rates are the same as the spreading rates, then at the subduction zones

crust is going into the subduction zones at 6-10 cm. per year.


     Usually, along the major Pacific subduction zones, there are many 

volcanoes.

At some level, material going down into the subduction zone has some chance 

of coming back to the Earth's surface via the volcanoes.  I'm not saying

that this will happen quickly.  The volcanoes are associated with the 

subduction

process.  So, if you dispose of reactor radwaste in subduction zones, there is

a chance it will re-appear at the Earth's surface in lava, ash, etc.


     I think re-processing of the rad waste is the way to go.  Separate the 

Uranium &

long-lived alpha emitters from the short-lived (300 years = 10 half lives; 

Cesium, Strontium, etc.) photon emitters.  Clearly re-processing is dose

intensive.  If we can do the re-processing remotely & robotically, so be it.

Clearly, Pu proliferation could be a problem.  But how about sending any 

produced Pu (from reprocessing) to Pantex in Texas regularly, where all the 

rest

of our Pu is????


      I guess we could store the waste for 300 years at Yucca Mountain, until

the heavy gamma radionuclides have decayed away significantly.  The remaining

long-lived alpha emitters shouldn't pose too much of a problem.  I know

I'm simplifying this all way too much.


     As for Yucca Mountain, I know this is a difficult process for all 

involved.

I was involved with the New Jersey LLRW Siting Process (as a groundwater

modeller), and to this day have wonderment about some of the things that

occurred then and there.  Fortunately, New Jersey did not spend as much 

money on this siting process as other states.  I remember some of the local 

geologists telling me about the North Carolina siting process.  At the NC

siting meetings, I'm told men in black hoods showed up for the discussions.

After the local siting board members had made their presentations, the men

in the black hoods (who may have been armed) responded: "We've heard

your (dose) numbers.  Now we have some numbers for you: 22 caliber,

357 magnum, and on and on...."  I don't think the men in the black hoods

were kidding.  I don't think that Nevadans are any less well armed.  I think 

such 

processes must go forward slowly.  And I don't think South Carolina will

continue taking LLRW ad infinatum.


     Well, clearly I've said too much already, as usual.  Have a good 

night!!!!


     

                                                Joe Preisig, Ph.D.