RE: Maple 1&2

["Franta, Jaroslav" <frantaj@AECL.CA>]

Dear Priya,



Here is a fairly recent media story on the project, from a local small town

paper.....



Jaro 

^^^^^^^^^^^^^^^^^^^^^



MAPLE reactor shut down again

North Renfrew Times, July 22, 2003 

by Terry Myers



The MAPLE 1 reactor at the Chalk River Laboratories has been shut down again

after further problems in its start-up commissioning process.The reactor was

placed in a "secure shutdown state" earlier this month after tests showed

the reactor operating with a "positive power coefficient."

The MAPLE reactor is designed to operate with a negative coefficient.

In a report to the Canadian Nuclear Safety Commission (CNSC), Barclay

Howden, the acting director general of nucler facilities regulation, said a

negative coefficient is part of AECL's "defence in depth strategy" for the

MAPLE reactors.

In crude terms, a reactor with a negative coefficient will gradually slow to

a stop if safety systems fail and there is no one at the controls.

A reactor with a positive coefficient would instead run faster and hotter

until it reaches the point of a meltdown.Howden said the positive reading

for MAPLE 1 was "contrary to the (reactor's) core design characteristic" and

"could have a negative impact on safety."

MAPLE 1 was shut down after the finding and MAPLE 2 has not yet been started

up.

"Neither reactor will be restarted until a mutually agreeable solution to

the positive power coefficient issue is found," Howden stated.

Despite the setback, AECL media relations manager Ian Dovey said the company

expects to get back on track quickly.

"Is there any danger? No," he said.

"Right now we're analyzing the situation, and once we've determined why this

has occurred, we'll ask the CNSC to allow us to continue on with

commissioning.

"We expect that will be before the end of the month."

AECL is building two 10-megawatt MAPLE reactors and a new isotope processing

facility (NPF) at Chalk River under contract with MDS Nordion.

Once complete, the MAPLE facilities will produce medical isotopes like

Molybdenum-99 that Nordion markets around the world, a job now done at the

NRU reactor.

MAPLE 1 set a milestone in February 2000 when it became the first new

reactor to go critical in Canada since 1987.

But work on the MAPLE project ground to a standstill later that year after

problems with the shut-off rods, one of the reactor's main safety systems.

AECL finally restarted MAPLE 1 last November after the CNSC approved

low-power commissioning of the reactor up to powers of 500 kW.

The company has set a target to complete commissioning and have the reactor

declared "in service" this September.





-----Original Message-----

From: Priya Doshi [mailto:apkd72@YAHOO.COM]

Sent: Friday September 05, 2003 1:55 PM

To: radsafe@list.vanderbilt.edu

Subject: Maple 1&2



I was wondering what the status, of the new Maple 1 & 2 reactors in Canada,

is?  They were supposed to be the new source for medical isotopes (Mo99).

Are they in active production yet?  Also, there was discussion about

switching fuels from HEU to LEU.  Has that progressed?

Thanks



Priya Doshi, Health Physicist

apkd72@yahoo.com