The researchers used the long-lived radioactive isotope chlorine-36
to estimate the age of the groundwater.
For this particular study, researchers measured decay rates of silicon-32 and chlorine-36
at Brookhaven National Laboratory (BNL) in New York.
Carbon-14, beryllium-10, aluminum-26, and chlorine-36
are also mentioned.
Under the proposed agreement, Ontario Power Generation expects to receive about 290 cubic feet of intermediate-level nuclear waste per year at the deep geologic repository, including carbon-14, with a half-life of about 5,000 years; nickel-59, with a half-life of 76,000 years; nickel-63, with a half-life of 100 years; iodine-129, with a half life of 15.7 million years; chlorine-36
, with a half-life of about 300,000 years; and many other isotopes with half-live exceeding 30 years.
Wang, "Short-lived chlorine-36
in a Ca- and Al-rich inclusion from the Ningqiang carbonaceous chondrite," Proceedings of the National Academy of Sciences of the United States of America, vol.
The animals were then sacrificed every 12 hr, and chlorine-36
tissue levels determined.
Tritium, an isotope of hydrogen, and chlorine-36
were also both absent from the Naimona'nyi cores, according to Natalie Kehrwald, a doctoral student at Ohio State and lead author on the paper.
At the same time, the team monitored a chlorine-36
4.3 x [10.sup.-9] 4.4 x [10.sup.5] years
Of these, most will be trapped by the clay buffer, and only two are likely to migrate very far: chlorine-36
The accumulation of cosmogenic chlorine-36
in rocks: A method for surface exposure dating.