Geography Reference
In-Depth Information
These problems are addressed by the study reported by Massone et al.
(2010), where different units with different categories of vulnerability in
geological homogenous environments are discriminated.
Also, use of qualitative adjectives such as ‗low' or ‗moderate' is avoided
because of their subjective meaning.
6.3.1. DRASTIC Method
DRASTIC is one of the most widely used standard groundwater
vulnerability methods, which was developed by the United States
Environmental Protection Agency (USEPA) as a method for assessing
groundwater pollution potential (Aller et al., 1987). Seven most important
mappable factors that control groundwater pollution were determined after a
complete evaluation of many characteristics and the mappability of the data;
the parameters are as follows:
Table 4. Conventional and modern methods for groundwater
vulnerability mapping
S. No.
Method
Parameters
Source
Methods for Porous Aquifers
D - Depth to water
R - (net) Recharge
A - Aquifer media
S - Soil media
T - Topography (slope)
I - Impact of vadose zone
C - (hydraulic) Conductivity of the
aquifer
DRASTIC
and Pesticide
DRASTIC
Aller et al.
(1987)
1
D - Depth to water
R - (net) Recharge
A - Aquifer media
M - Aquifer thickness
I - Impact of vadose zone
C - impact of Contaminant
Wang et al.
(2007)
2
DRAMIC
G - Groundwater occurrence including
recharge
O - Overlying lithology
D - Depth to groundwater
3
GOD
Foster (1987)
Stempvoort et
al. (1992)
4
AVI
c - Hydraulic resistance
