Geoscience Reference
In-Depth Information
Fig. 6. Computed Ra-226 concentration in waste site, beach, and observed concentra-
tion in coast.
9
concentration from waste disposal site to beach is shown in Fig. 6. The
groundwater discharge from the waste disposal site between the east and
west creeks is computed by applying Darcy's law.
The groundwater flow to Lake Ontario from the site is 2
.
5
10
5
m
3
/year.
This annual volume of water is about 3%-4% of the total solid volume of
the site, assuming a depth of about 35 m. If the
226
Ra activity in the shore
piezometers averages about 100 Bq/m
3
,about2
.
5
×
10
7
Bq/year is carried
into the lake. But the total amount of
226
Ra which has been disposed of at
thesiteis2
.
3
×
10
13
Bq, so that only about 10
−
6
of this is lost from the site
per year. A comparable calculation for uranium indicates that about 25 kg
of this element reaches the lake. The details of the application of model and
interpretation of results were presented earlier.
9
×
3.4.
Casestudy3:Godavaridelta,India
The Godavari delta is located in East Coast of India (Fig. 7). The details
of geology and environmental problems have been explained earlier.
10
The
Godavari delta lies between the sea level and 12 m contour. The delta has
a projection of about 35 km into the sea from the adjoining coast.
The Godavari delta consists of alluvial plain. It has a very gentle land
slope of about 1 m per km. The coastal line along the study area measures
to about 40 km and the general elevation varies from about 2 m near the
sea to about 13 m at the upper reach. Texturally, a major part of the study
area consists of sandy loams and sandy clay loams. The silty soils, which
are very deep, medium textured with fine loamy soils is located all along the
Godavari River as a recent river deposits. The very deep, coarse textured
