2
1. Introduction
spread so slowly that the groundwater contamination may remain undetected for a long time. Hence, the potential danger of groundwater contamination is often ignored. Actually, groundwater is being polluted on a large
scale in some cities and districts due to human activities. Groundwater is
generally hard to clean up once polluted. The predictive calculations for
some aquifers have shown that even if the pollution source has been removed, self-purification will take several decades, or even hundreds of years.
It is more difficult to clear away groundwater pollution in fine porous media.
High costs and a long period oftime are needed for remediating groundwater
pollution compared to what is required for surface water. Therefore, preference should be given to prediction and prevention, as well as regular monitoring and analysis, of groundwater quality.
The analysis of water quality involves the measurements of physical properties, chemical and/or biological components of a water sampie. The result
of water quality analysis gives the concentration value C" of any designated
component oe in a sam pie. In order to describe the degree of contamination in
an aquifer and to monitor the changes in groundwater quality, it is necessary
to sampie and analyze the water quality at different locations and times.
The distribution of concentration C" in space and time is called the concentration field and is written as CAx, y, z, t). The results obtained from monitoring and analyzing are discrete observation values of the concentration
field:
i = 1,2, ... , I,
j = 1,2, ... , J,
where I is the number of observation points,
J is the number of observation times,
I· J is the total number of sampies.
(1.1.2)
From the mathematical point of view, any distributed scalar field, such as
a concentration field C,,(x, y, z, t), can be displayed approximately by a set
of discrete values in space and time, such as the observed concentrations
given in Eq. (2.1.2), provided that the observation locations and times are
appropriatelyarranged.
1.2 Groundwater Quality Management
The groundwater resource is limited. The best use of the limited resource
with maximum economic benefit can only be obtained through scientific
management and rational utilization. An incorrect management decision
not only causes economic waste and resources destruction, but also brings
1. Introduction
spread so slowly that the groundwater contamination may remain undetected for a long time. Hence, the potential danger of groundwater contamination is often ignored. Actually, groundwater is being polluted on a large
scale in some cities and districts due to human activities. Groundwater is
generally hard to clean up once polluted. The predictive calculations for
some aquifers have shown that even if the pollution source has been removed, self-purification will take several decades, or even hundreds of years.
It is more difficult to clear away groundwater pollution in fine porous media.
High costs and a long period oftime are needed for remediating groundwater
pollution compared to what is required for surface water. Therefore, preference should be given to prediction and prevention, as well as regular monitoring and analysis, of groundwater quality.
The analysis of water quality involves the measurements of physical properties, chemical and/or biological components of a water sampie. The result
of water quality analysis gives the concentration value C" of any designated
component oe in a sam pie. In order to describe the degree of contamination in
an aquifer and to monitor the changes in groundwater quality, it is necessary
to sampie and analyze the water quality at different locations and times.
The distribution of concentration C" in space and time is called the concentration field and is written as CAx, y, z, t). The results obtained from monitoring and analyzing are discrete observation values of the concentration
field:
i = 1,2, ... , I,
j = 1,2, ... , J,
where I is the number of observation points,
J is the number of observation times,
I· J is the total number of sampies.
(1.1.2)
From the mathematical point of view, any distributed scalar field, such as
a concentration field C,,(x, y, z, t), can be displayed approximately by a set
of discrete values in space and time, such as the observed concentrations
given in Eq. (2.1.2), provided that the observation locations and times are
appropriatelyarranged.
1.2 Groundwater Quality Management
The groundwater resource is limited. The best use of the limited resource
with maximum economic benefit can only be obtained through scientific
management and rational utilization. An incorrect management decision
not only causes economic waste and resources destruction, but also brings