[ RadSafe ] FW: spam: FW: 'Exit' signs boost landfill radiation levels

Fri Apr 7 12:41:31 CDT 2006

Doubtful on a number of fronts.

One: When tritium exit signs, which typically contain about 20 curies of  
tritium gas, are ruptured, the tritium gas quickly dissipates in air.  Tritium 
gas has a profoundly low exchange rate with non-radioactive-hydrogen in  water 
under ambient conditions, so profoundly little absorption of the  tritium by 
groundwater would occur. There is likely no more than a  billionth or trillionth 
of a fraction of exchange that would establish a  significant pathway of 
sanitary landfill exit sign tritium to groundwater. Also,  landfills by their 
design are not built to have direct contact with groundwater  for obvious 
pollution-minimization reasons. Tritium gas is very challenging  to keep contained due 
to the small size of the molecule and has a natural  tendency to migrate 
upward (all hydrogen gas, even tritium, is lighter than  air). It is not 
conceivable that tritium gas liberated from an exit sign could  be trapped for long 
inside a landfill. Moreover, there is no thermodynamic  mechanism that would 
persuade tritium gas to head downward to  groundwater. There might be a rainwater 
vehicle, but this mode producing  substantial levels of tritium in groundwater 
from landfill exit signs  intuitively seems improbable, and this writer is 
unaware of  any objective proof of this mode.

Two: Tritium has never been shown to cause cancer. The claim to the  contrary 
in the article below is without merit. The simplistic and sophistic  claim 
that ''Radioactivity causes cancer' does not constitute  scientific proof. The 
inherent radiological weakness of tritium further  undercuts the implication.

Three: Tritium exit sign manufacturers have modeled extensively  the 
potential dose consequences of full release of the tritium content of  signs in an 
enclosed workspace. they have determined that the maximum  dose that an 
individual could ever receive from the tritium gas of a broken  sign would not exceed 
the annual dose limit for a member of the public.  That is one of the reasons 
why the activity content of tritium in signs is  limited to about 20 curies per 
sign.

Four: DEP's efforts to keep tritium out of landfills will be  complicated by 
the disposal of other tritium-containing manufactured products  there, such as 
tritium wristwatches. There is no law that prohibits  disposal of such items 
in sanitary landfills.

Five: The context of the reference below to the EPA drinking water standard  
of 20,000 pCi/l of tritium is misleading. The EPA drinking water standard 
means  this: an individual would have to drink two liters of 20,000 pCi/l water 
every  day for a year before he or she would receive the maximum allowable dose  
from drinking water set by the EPA, which is....4 mrem. That is  
one-twenty-fifth of the total annual dose allowed to a member of the public set  by 
federal regulation. Moreover, the standard applies only to potable water.  
Groundwater is not generally potable, so any tritium that it contains is less  likely 
to find a pathway to human uptake. Non-potable  groundwater makes the EPA 
drinking water standard non-applicable  to tritium in such groundwater. And 
finally, the EPA standard is only that:  a standard. It is not a rigid limit. 
Exceeding the standard at any  instant does not automatically constitute a regulatory 
violation or public  health hazard. It is instead one factor to be used in 
assessing the  potential to the public over a period of time.

Six: So if the tritium in the groundwater is not likely coming from tritium  
exit signs, what other explanations are there? Here are two possibilities: One 
-  sample preparation and/or analytical error. Two - medical use or  
biomedical research discharges to the environment. My guess would be the first  
possibility. It is easy to find 'tritium' in 'high' levels in water samples if  care 
is not exercised in collection, preparation, and analysis of the samples.  
That is why it is vital to split such environmental samples and have them  
prepared, counted, and their results interpreted at separate  labs before making 
apocalyptic pronouncements.

Three other possibilities are much less likely: natural tritium production  
in the environment, neutron interaction with the soil, and discharges from  
nuclear power plants. Mother Nature produces 4 MILLION curies of  tritium  every 
year, but spreads it out over the Earth. The resulting concentrations  in air 
and water are insignificant. Neutron interaction would have to  present at 
extremely high levels to produce measurable tritium production  in groundwater. 
Such high levels typically are produced by subterranean  high-energy research 
accelerator beamdumps, of which there are no more than a  handful in the 
country. And there are no nearby nuclear power plants that have  been mentioned in 
the below article. In any event, nukes adhere to rigorous  effluent discharge 
limits to the environment, and are both unlikely and not  historically known to 
be sources of tritium in groundwater at such 'high'  concentrations.

Seven: If there remains serious concern about tritium in landfills, then  the 
antinuclear groups ought to champion the establishment of affordable  
disposal options for such literally low-level radioactive wastes.

Steve
Steven R.  Frey, MS, CHP

In a message dated 4/7/2006 7:54:40 A.M. Eastern Daylight Time,  
ncohen12 at comcast.net writes:

Coalition for Peace and Justice; UNPLUG Salem Campaign, 321 Barr  Ave,
Linwood; NJ08221; 609-601-8583

-----Original  Message-----
From: Eric Epstein [mailto:ericepstein at comcast.net] 
Sent:  Thursday, April 06, 2006 11:32 PM
To: Norm Cohen
Subject: spam: FW:  'Exit' signs boost landfill radiation levels

'Exit' signs boost  landfill radiation levels

Discarded green-glowing signs, containing  radioactive tritium, contaminate
landfill water here and across state.  Experts say levels don¹t pose health
threat.

By Ad  Crable
Lancaster New Era

Published: Apr 05, 2006 1:50 PM  EST

LANCASTER COUNTY, PA - When state inspectors began finding  elevated levels
of radioactive tritium at landfills across Pennsylvania ‹  including four in
or near Lancaster County ‹ they were  puzzled.

After all, new regulations required all landfills to monitor  incoming
trucks for any radioactive material.

The origin, they found  to their surprise, was exit signs.
At three of the four landfills here, and  at more than half the 54 solid
waste landfills in the state, the levels of  tritium in water flowing from
the landfills exceeded what is allowed in  drinking water.

Above-normal levels of tritium were found at the  county¹s Frey Farm Landfill
in Manor Township; the Lanchester Landfill on  the Lancaster-Chester border;
the Conestoga Landfill on the Lancaster-Berks  border; and the Milton Grove
Demolition and Tire Recycling Center near  Mount Joy.

Advert 

All but the Frey Farm Landfill had tritium in  leachate ‹ the water that
flows down through waste ‹ at levels exceeding  drinking water standards.
That water is discharged into such waterways as  the Conestoga River,
Susquehanna River and Little Chickies  Creek.

State Department of Environmental Protection officials emphasize  that the
levels of tritium found do not pose a health threat to residents  here or
anywhere else in Pennsylvania because the tritium is vastly diluted  before
reaching any drinking-water intakes.
³It truly would be a  fraction² of original levels, says DEP spokesman  Ron
Ruman.

Three-page letters to head off public alarm were recently  sent by the DEP to
local officials whose municipalities host the  landfills.

But the DEP wants to keep tritium out of landfills. So they  searched for the
source of the radioactive gas, at high levels a  cancer-causing agent
normally associated with the production of nuclear  energy.

Tritium gas is typically used in the green exit signs placed in  many
buildings so that the signs continue to glow in case of a power  failure.
Red-lettered exit signs do not contain tritium.
State and  federal laws require that unused exit signs be sent back to  the
manufacturer, where the tritium is removed and recycled, or taken to  one of
the two low-level radioactive waste landfills in the United  States.

But the reality is that many, perhaps most, of these exit signs  get thrown
out with the trash or taken to landfills when old buildings are  demolished,
the DEP says.

When the signs reach landfills and are  broken, the gas quickly finds its way
into water that flows through  landfills.

Radiation monitoring at the landfills does not detect the  incoming signs
because they give off beta radiation, which the detectors  don¹t pick up,
Ruman said.

Federal drinking-water standards allow up  to 20,000 picocuries per liter of
tritium. At the Conestoga Landfill,  collected leachate had nine times the
maximum level allowed ‹ the highest  of any landfill in the state.

At Milton Grove, in Mount Joy Township,  one sample found 29,300 picocuries.
At Lanchester, the highest level was  30,900. At Frey Farm, the highest level
found was 6,540. Leachate there is  pumped to the nearby Lancaster Area Sewer
Authority treatment plant and  discharged into Dry Run, a tributary of the
Susquehanna. Manor Township  supervisors recently received a letter from the
DEP about the tritium  finding at Frey Farm.

Supervisor John May said he was relieved that  drinking water sources do not
seem to be affected. ³There¹s no way to  remediate this, apparently,² he
said. ³I guess the idea is to stop the  practice of throwing them away
indiscriminately.²

The DEP has  appealed to the U.S. Nuclear Regulatory Commission to do a
better job of  labeling and informing the public about the proper disposal of
exit signs  containing tritium.
In addition, the DEP is now requiring the 54 landfills  to begin testing for
tritium in leachate.
Tritium has had a high profile  in the news lately. Unreported tritium leaks
at three nuclear plants in  Illinois prompted the state attorney general to
sue Exelon Corp. over  groundwater contamination.

Exelon launched a fleet-wide search for  tritium leaks, including at its
Three Mile Island and Peach Bottom nuclear  plants.

A leak of tritium into groundwater at TMI occurred last summer,  but levels
never exceeded drinking-water standards and didn¹t reach the  Susquehanna,
Exelon officials said.

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