RE: Background radiation for Pacific NW cities

["Weiner, Ruth" <rfweine@sandia.gov>]

The upstream (from Hanford) radionuclides come in part from leaching of a
fairly young unmined uranium deposit on the Colville reservation.  The best
study I know of was done about a decade or more ago by David Stewart-Smith
of the Oregon DEQ, who traced the effluent from the old once-through cooling
systems from the Pu production plants.  More recently, some good data can be
found in  the Columbia River Comprehensive Impact Assessment.  I have mixed
sentiments about the assessment itself -- I was on the "review team" and had
some pungent comments to make -- but the data are interesting.

Ruth F. Weiner, Ph. D.
Sandia National Laboratories 
MS 0718, POB 5800
Albuquerque, NM 87185-0718
505-844-4791; fax 505-844-0244
rfweine@sandia.gov

-----Original Message-----
From: Dukelow, James S Jr [mailto:jim.dukelow@pnl.gov]
Sent: Monday, July 19, 1999 7:18 PM
To: Multiple recipients of list
Subject: Background radiation for Pacific NW cities



As a partial, but mostly unsatisfactory, response to Jonathan Wiles question
of
14 July --

Because of geology, Spokane is a region of fairly high radon and the rest of
the
state of Washington and Portland are low to medium radon areas.  Although
much
of the nation's weapons plutonium was produced in the Tri-Cities,
environmental
Pu levels are higher west of the Cascades (Portland and Seatlle), because
they
are dominated by rain-out of Pu from bomb testing in the 40s through the
60s.
Those of us in the ever-brown corner of the Evergreen State don't suffer
that
much from rainfall.  Interestingly, levels of some radionuclides in the
Columbia
River are higher upstream from Hanford than downstream, for reasons that are
not
completely clear.   Some springs along the Hanford shore of the Columbia
contain
higher than EPA drinking water standard levels of strontium-90, but levels
of
all radionuclides in the main flow of the Columbia are well below drinking
water
standards, which is nice, since that is what we drink in the Tri-Cities.

I did a modest search for web sites that would document the above folklore,
without success.  The Washington State Departments of Health and Ecology web
sites seemed to be innocent of any information about background radiation,
although richly supplied with information about I-131 releases from Hanford
that
decayed away 40 to 55 years ago.

The maps referred to in replies by Baker and Frame show: 1) Spokane as a
region
of high radon, but medium uranium, thorium, potassium, and terrestrial
gamma, 2)
the Tri-Cities with medium radon, low potassium, and low to medium uranium,
thorium, and terrestrial gamma, 3) Portland similar to the Tri-Cities, and
4)
Seattle with low radon, uranium, thorium, and terrestrial gamma, but high
potassium levels.  Certain aspects of the way the maps are presented on the
web
site leaves some residual uncertainties about the levels, particularly for
Seattle, where the color used to represent shorelines (with which Puget
Sound is
richly supplied) is the same as the color used to represent high levels of
the
radionuclide.

High radon on the USGS map is greater than 4 pCi/liter for average
residence, so
by the usual conversion, radon background for Spokane would be around 800
mrem/year.

Altitudes for Portland and Seattle are effectively sea level, the Tri-Cities
sits at about 400 feet, and Spokane at about 2200 feet.

Best regards.

Jim Dukelow
Pacific Northwest National Laboratory
Richland, WA
jim.dukelow@pnl.gov

These comments are mine and have not been reviewed and/or approved by my
management or by the U.S Department of Energy.
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