Residual contamination and environmental effects at the former site of Vanda Station, Antarctica

Abstract

Vanda Station was New Zealand’s only base on the mainland of Antarctica from 1968 – 1993, when it was regularly occupied by a small team of people over the summer field season. The base was decommissioned and removed in 1993/94, as the level of Lake Vanda rose, threatening to inundate the site. Contaminated soil was removed from the site during the decommissioning process, but environmental assessments in 1996/97 identified minor residual contamination of soils close to buildings, helicopters pads and in “Greywater Gully”, a low-lying area formerly used for the disposal of greywater waste from the base. Trace elements, hydrocarbons and nutrients were the principal contaminants identified, and their potential impact on lake water quality and microbial mat health, when soils flooded, was predicted to be minor. In the 2014/15 summer field season, 20 years after the removal of the station and with the site now mainly under water, another environmental assessment has been undertaken to test these predictions.