Wednesday, November 28, 2012

Radioactive trowels and robots

Today there was an interesting item on the US Nuclear Regulatory Commission's blog about a radioactive trowel.  Here's the item, about how the president almost handled a radioactive trowel:

Uncovering the real story of Joe Ball's trowel required research at the Department of Energy's archives, where I could get more information about the AEC’s move from Washington, D.C., to Germantown, Md., in 1957. The AEC's move was precipitated by the Soviet Union development of thermonuclear weapons. To survive a 20 megaton blast over the capital mall, AEC offices needed to be at least 20 miles away. Germantown was selected over 50 other sites.
This Cold-War move coincided with new initiatives by the AEC to promote civilian nuclear power plant construction. Thus, the dedication ceremony became a chance to highlight the atom's contribution to national defense and its potential peaceful applications.
The AEC created a ceremony heavy in symbolism. Electricity from batteries charged by eight military and civilian power reactors lifted a curtain on a commemorative plaque in the new building lobby. A time capsule was placed behind the cornerstone packed with military and civilian artifacts, such as pictures of the Nautilus and scraps of linen wrappings for the Dead Sea scrolls dated by radiocarbon techniques.
As I found out from the DOE archives, AEC Chairman Lewis Strauss wanted even more symbols for the dedication ceremony. He asked for a trowel with some historical significance and Argonne National Laboratory obliged, including, as mentioned in Part I, creating a blade made from uranium. AEC officials liked the trowel and planned on giving speeches about its symbolism to local groups.
But there was a problem.
The uranium metal had been reused for many years in other experimental reactors, most likely in the CP-2. The uranium was still radioactive, enough that an Argonne official told the AEC to use only the handle and not touch the blade. Hoping to preclude objections from the White House, the AEC medical staff reassured the Secret Service that the trowel was a “unique opportunity” for Eisenhower “to demonstrate under completely safe conditions the proper way to perform an operation involving radioactive material.”
AEC assurances didn't work. Ike's staff refused to allow the president to touch anything radioactive. Stymied, the AEC substituted three silver-plated trowels. The uranium trowel was dropped from the ceremony and the silver-plated trowels that history records were used instead. The fate of the symbolic trowels – of which there were either two or three – were mostly lost to history, with one spending decades in storage at Eisenhower College's old campus.
Joe Ball's unusual auction win find reminds us why we love artifacts—their stories are fun. They teach us about the society that made them. The CP-1 trowel was born out of an optimism in the possibilities of the atomic age, but even in the 1950s radiation concerns proved powerful. Today most people likely sympathize with the White House's fear of radiation, and the trowel probably seems like a questionable use of radioactive material.
And so Argonne's creation reminds us how the nation had changed in the last half century in shifting to a more sober attitude toward nuclear hazards.
Joe Ball has graciously agreed to loan the trowel to the NRC , where it is now displayed in our lobby.
Tom Wellock
NRC Historian

Also today, an item in the news about Chernobyl's new containment structure coming closer to being completed. 
It seems to me that robots should be the only ones handling radioactive trowels.  

Saturday, November 17, 2012

Building a water storage tank

Today I'm looking back at the construction of a water storage tank.  It's now all done, and it's interesting to look at how it came together.  This tank is made from manufactured concrete block, using a method which I have several patents on.  I've posted several pictures below showing the construction steps.

This particular tank has an inside diameter of around 7 feet.  It holds around 3,000 gallons.  It is being used as a rainwater harvesting (rwh) tank.  I am using it as a plunging tank to cool off after you take a sauna, which I also built.  The tank has an electric light (LED's) at its bottom center.  There is a ladder which conforms to its spherical inner shape, for easy "in & out."

This tank was easy to build, and should last a very long time.  I hope to be using it to collect rainwater and as part of my wood-fired sauna experience for years to come.  If we assume concrete block cost $1 each, this tank cost me $175, which seems like a pretty good value.  Similar tanks for rainwater harvesting can have many uses: from potable water, to fire suppression systems, to watering crops, etc.  It has a hinged lid to keep insects out and to keep the water clean.  Rainwater is collected from the sauna roof, which is around 1,000 square feet.

I hurt myself (chainsaw accident!) while I was working on this, it took some time to heal.  The actual time to build this entire thing was very short though; less than a week.
The grey plastic pipe was used to run electric wire for the underwater light: thinking ahead.

Some of these mortar joints (especially near the top) are intentionally extra 
thick, this stretches the sphere and makes the water tank deeper. Easily done.

This is the electric light I installed in the bottom center of the tank.  LED's.
The light installed.  It is over 8 feet down to the bottom.

This is the finished tank, with my puppy Bartleby investigating.

Here is the actual sauna room.

 Here's a shower I put in.  The building also has a toilet, sink, bedroom and upstairs deck (outside).

This was a fun project, and I can't wait to use it!