HYDRAULIC CONDUCTIVITY BEHAVIORAL DEVELOPMENT ON ARTIFICIAL VEGETATION SUBSTRATES (made by coal fly ash, gravel G5 and clay) FOR THE COAL MINING RECLAMATION PROJECT „OBERDORF“ GKB-Bergbau GmbHKÖFLACH AUSTRIA

 

by :

 

Anggoro Tri Mursito

 

Research Centre for Geotechnology

Indonesian Institute of Sciences (LIPI)

Jl. Sangkuriang, Komplek LIPI Gedung 70, Bandung 40135

anggoro@geotek.lipi.go.id

 

abstract

 

An artificial soil mixed made out of electrical-coal power plant wastes (fly ash) and

material from the coal mine sites (clay and gravel G5) has been created for the

reclamation of open pit mine site. Physico-chemical properties were measured over

time to examine them in a chronosequence of 22 plots (each 400m2) with

systematically changing mixtures (1,2 and 3 components of varying proportions were

established and planted. In the field plots, available nutrient content was initially high

but established only for some of plots. Due to ecological function measurement,

physical parameter, which is hydraulic conductivity, is one of several physic

properties will have to be monitored and analysed.

 

According to the development value of the year of 2003 (spring) shows that

increasing of water permeability classes (class 6) is leaning to the direction of fly ash

and tegel (clay) composition. Class 5 are only in the trial plot number 5 and 9. Only in

one trial plot which is drop in class 4 (trial plot 16), but it is still classified into "good"

class (according to "Arbeitskreis Standortskartierung, 1996"). The trial plot number 1

has also classified into class 6, because the substrate composition in this trial is only

100% of gravel. It has to be the highest class, but it is not always the highest value of

water permeability. All the trial plots are classified into high to very-very high.

Compared results between initial (spring, 2000) and recent measurement (spring,

2003) is shown that extremely increased in the trial plot 3 and 13. In the year of 2003,

in trial plot number 3 and 13 are suddently flare up to 4 classes (from class 2 to 6).

As also analysed by Computed Tomography images of one component substrate

(100 % of tegel) shows that cracked structures clearly appear as a results of

decreasing precipitation in the last winter and also highly increasing of temperature

as well. High percentage of cracked means that water can easily flows. Most of the

trial plots are increasing of classes due to the season differences. The others (trial

plot number 1, 5, 6 and 9) remain in the same class.