Radon-222 Measurements at Wairakei, Broadlands and Ngawha

Abstract

The work reported here originally had its impetus in the paper of -Axtman (1975) and comment aroused by it.

METHODS The method used for estimation of radon is based on that of Kerr et at. (1962) as modified by Gregory (1976). It was designed for measuring radon in water, and is modified here to measure radon in steam.

A t Hairakei, the bores selected were known to emit widely varying chemical compositions, and it was thought .this might yield interesting information.

At Broadlands, as many bores as were open were sampled. In addition, analyses were performed on the water of the Waikato River.

The material emerging from the bores at Wairakei and Broadlands is a mixture of steam and water, and the water is separated from the steam in a cyclone separator. This water currently flows to waste, and might contain and release radon to the air. It was therefore analysed.

At Ngawha, samples were not collected from the bores which were very few in number, but from the hot springs only.Collection was done by G.L. Lycm of this Institute.

A final sample type was the stack gases at Wairakei.. The separated gases from the condensed steam in the power station are mixed wirh air (about 1:2) and allowed to escape to the atmoshere through four stacks.