Ramachandran, Kausalya 
  
to good groundwater potential were severely affected with H-acid conc. ranging from < 4000 to 7000 mg / kg in subsoil 
to 4000-6000 mg/kg in surface soils (Fig.3). A union of maps of spatial spread of H-acid conc. in groundwater with that 
of groundwater potential in Bichhri in 1992, indicated the magnitude of H-acid contamination in groundwater. It was 
seen that H-acid conc. varied in different parts of the aquifer as mentioned earlier. By 1998, however, the H-acid conc. 
declined drastically; maximum H-acid conc. in well water was noted as 50 mg/l in an area of 0.04 Km”. Total area of 
3.4 Km’ of aquifer was estimated to be affected by H-acid conc. of 2- 40 mg/l. 
  
H-acid Concentration in sub-surface soil in Bichhri, Rajasthan, 
India - July 1998 N 
        
         
    
  
Kms 025 0 0.25 0.50 0.75 1.00 Kms 
   
  
p i N 
== SE R 
mI 
A TUN A 
TS 
   
  
Scale 
  
  
  
  
  
  
  
   
    
   
S H-acid Conc. (mg/Kg) 
E 
AAA, 
sod 
AM 
m 
ill 
[n 
  
  
art 
Udaisagar TUI 4000. 5000 
Reservoir 1 
i «4000 
  
  
  
  
  
  
Figure 2. H-acid concentration in sub-surface soils from Bichhri village in July 1998 
Digital Interpretation of IRS - 1A and 1B LISS - II data of 1992 and 1998 and a subsequent map overlay in GIS, 
indicated the land use dynamics in the region as a consequence of contamination. It was noticed that cultivation 
associated with onset of monsoon 'Kharif improved marginally between 1992 and 1998. In 1992, Kharif cultivation 
was confined to an area of 0.22 Km? which marginally increased to 0.31Km?® in 1998. The effect of groundwater 
contamination was obvious in case of post-monsoon season cultivation ' Rabi’, where groundwater is the only source 
for irrigation. In 1992, an area of 0.36 Km? was cultivated under Rabi , Which increased to 2.0 Km? in 1998, owing to 
the decline in H-acid conc. in water. Spatial extent of fallow land fluctuated proportionally with H-acid conc. in 
groundwater. Analysis depending on map overlay of Land use/land cover of 1992 and 1998, highlighted some 
disturbing trends. Owing to contamination agricultural land first fell fallow for over five to seven years. This was 
followed by encroachment on marginal land, such as open scrub and unreserved forest, which until then had acted as 
bio-reserves. Human encroachment on these fragile ecosystem, would further aggravate the ecological debacle. 
4. CONCLUSION 
Dispersal of contaminant from a point-source and its impact on agriculture, socio-economic life of rural people in 
Bichhri and on the livestock, could be assessed with ease, using satellite data from Indian Remote sensing satellites and 
ARC/INFO GIS. Map overlay and union provided statistics regarding the spatial extent of soils and groundwater 
contamination, which in turn, has facilitated the estimation of cost of ameliorative measures to be undertaken. Temporal 
assessment of soil, groundwater and land use/ land cover have indicated the fall in H-acid concentration levels in 
groundwater and soils; however, H-acid traces are still to be found in soils and groundwater in Bichhri which makes 
them unsuitable for any use. 
  
  
1228 International Archives of Photogrammetry and Remote Sensing. Vol. XXXIII, Part B7. Amsterdam 2000.