by Jeff Tollefson >The New Mexico Environment Department has found contamination in yet
another spring seeping into the Rio Grande below Los Alamos National
Laboratory.
Uranium, tritium and nitrates turned up in a spring that was discovered
last fall, according to the department. Although the contaminant levels
didn't exceed state and federal water standards, the Environment
Department
cited the pollution as further evidence that groundwater could move much
faster than projected by the lab.
"Things are not as rosy as they would have it," said James Bearzi, chief
of
the department's Hazardous Waste Bureau.
Los Alamos officials last year released a groundwater model indicating
it
could take thousands of years for groundwater below the lab to reach the
Rio Grande and Santa Fe's water supply at the Buckman wellfield.
Testing of water from Buckman wells has never turned up the contaminants
in
question.
While it does not convey an immediate threat to the city's water supply,
Environment Department Oversight Bureau chief John Parker said such
evidence calls the lab's modeling into question. In some cases,
department
officials say, the time frame might be decades, not millennia.
Other contaminants have turned up previously in nearby springs along the
river, state officials said, although the lab has disputed the existence
of
certain contaminants or said they might originate from other sources.
Lab spokesman James Rickman on Friday questioned the latest results of
state testing. The uranium could occur naturally, he said, while
nitrates
could come from the White Rock sewage facility. And tritium shows up in
surface waters worldwide due to residual contamination from nuclear
testing, he said.
"All data are useful, but it's certainly too early to discount or
validate
any one particular (groundwater) model," Rickman said. The lab will
revise
its models as new information turns up, he said.
Parker conceded that all the possibilities mentioned by Rickman are
legitimate. State scientists considered the possibility that the sewage
plant affected its results, he said, but the overall water chemistry
doesn't appear to match up with what would be expected if that were the
case. The sample seems more similar to contamination found in Pajarito
Canyon, he said.
And while the state reported that uranium previously has not turned up
in
springs on the west side of the Rio Grande, Rickman said the lab has
consistently found uranium in those same springs. The discrepancy is one
of
many that must be resolved as the state and lab try to determine how
contamination from the lab might spread.
It is possible to test the uranium for evidence of weapons activities,
but
such tests have not been done, Parker said. "We hope to be able to
sample
this spring some more and try to get a better handle on this."
One thing is certain: Groundwater movement will play a critical role in
cleanup decisions regarding waste pits and other pollution at the lab.
Los
Alamos officials have said they want to leave many waste pits in place,
arguing that digging them up would cause more problems than it would
solve.
Such an assertion depends on water, however, or the lack thereof. Given
enough time, water tends to erode, penetrate and disperse almost
everything. The lab argues that local geology and an arid climate are
likely to keep the pollution safely in place well into the future.
If the latest contamination stems from the lab, however, that would
indicate that groundwater could reach the river in several decades,
according to the Environment Department.
"We don't know the pathways very well, and neither does LANL," said John
Young, a geologist with the Environment Department.
The lab asked for an exemption from monitoring groundwater several years
ago, arguing that geology would prevent contamination from reaching the
aquifer, according to Parker. The department denied that request and
subsequently implemented a groundwater-monitoring program, which is part
of
a broader effort to delineate the presence and movement of pollution at
the
lab.
"What we are learning is that there is more (contamination) down there
than
anybody thought," Bearzi said.
"Half the time a well goes in, they find some contaminant down there
that
is likely lab-derived."
A recent paper prepared by state environmental scientists for the U.S.
Geological Survey cites the detection of the industrial chemical
perchlorate in a Los Alamos County water-supply well in Pueblo Canyon.
That
pollution might have traveled five miles - half the distance to the
Buckman
wellfield - in fewer than 54 years, according to the paper.
State officials also detected perchlorate in springs along the Rio
Grande,
although lab officials also question those results. Parker said the
state's
test results for perchlorate at the new spring are incomplete.
Perchlorate and other contaminants could come from various lab
facilities,
including the liquid radioactive waste treatment facility at Technical
Area
50.
Department officials located the new spring while meeting with Concerned
Citizens for Nuclear Safety. The group conducted a three-day float trip
down the river in October.
The spring would have been inundated under normal conditions, but the
river
was unusually low at the time, officials said.
"This is an example of citizen monitoring of the environment around Los
Alamos," said Joni Arends, who heads the group. |
