673

Site number:

673

Authors:

IBC, GGC

Date recorded:

1992/12/23

Reason Sampled:

assessment of environmental impacts from past human activities at Vanda Station; determination of nature of contaminants and the depth of contamination

Description:

on the lower slope of a shallow elongated gully, 60m ESE of the main Vanda Station building; the site is 8.5m below and down slope from a greywater disposal point and .5m above the lowest point of the gully

Altitude:

93 m

Aspect:

ESE

Slope:

4 °

Climate

Soil climate zone:

central mountain

Estimated mean annual temperature:

-20 °C

Frozen ground depth:

35 ~ cm

Frozen type:

dry frozen

Frozen comment:

~35cm

Geology

Geological setting:

the rocks of the area are granodiorites that have been cut with lamprophyre dykes and form a strongly undulating ridge and gully topography as a result of ice over riding from down-valley and up-valley glaciations and to a lesser extent, subaerial weathering; cryogenic weathering, probably assisted by repeated past rises and falls of waters in Lake Vanda, has generally given rise to a heavily fractured upper bedrock surface with common angular platy boulders; sands, derived partly from sorted lake sediments and also from aerial erosion fill most of the rock fracture interstices

Patterned ground:

nil

Surface weathering or surface features:

Soil

Soil parent material:

fragmented granodiorite bedrock with a fine fraction of dominantly aeolian/fluvially sorted sandy material; in part contaminated by anthropogenic action (greywater discharges)

Previous disturbance:

a lower slope at a site of disposal of domestic waste waters

Soil weathering stage:

6 1 (Campbell & Claridge 1975)

Soil moisture status:

xerous; soil surface very occasionally moistened by summer snowfall; the site has received some runoff in the past from discharge of Vanda Station greywaters

Biological activity:

nil