الفهرس 
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Abstract
In the present work the gamma spectrometry technique has been
utilized to detect the activity concentrations attributed to 40K and both
uranium and thorium series. The measurements have been undertaken
for soil and sediment samples in front of different cities(regions)
along Rashid branch of the River Nile. The obtained results are
relatively small compared with the values commonly assigned as the
world average except that of the soil samples collected from Kafr-
Elzayyat because they are close to a phosphate fertilizer plant which
have higher concentration values for226Ra (108.6±1.86 Bq/kg) than
the worldwide levels .Moreover, soil samples from Rashid coast
along Rashid city have also high radioactivity levels of 226Ra(46±1.23
Bq/kg) and 232Th(61±1.4 Bq/kg).The corresponding values for
sediment samples at Rashid coast are 93.85±1.4 Bq/kg for 226Ra and
112±1.78 Bq/kg for 232Th which are higher than the world
recommended level 32 Bq/kg for the former and 45 Bq/kg for the
later. These higher values are a consequence of the existence of the
black sand along Rashid coast which is highly rich with natural
radionuclides. Dose assessment and hazard indices criteria were
calculated and discussed. from the calculations, it is found that the
absorbed dose rate, annual effective dose, the external and internal
hazard indices and the representative level index exceed the regular
limits in particular at sampling locations along Rashid and Kafr-
Elzayyat (coast).
The precise analysis of some selected sediment samples by
means of alpha spectrometric analysis reveals that the ratio of
234U/238U is nearly one indicating case of secular equilibrium between
Chapter Four Conclusion
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them. Also, The values of 235U activities were estimated and is equal
to or less than 0.7 % of the total uranium.
Finally, the obtained results may be used to collaborate in the
development of the Rashid branch by taking into consideration the
possible solutions such as preventing all types of wastes to be fall
into the stream by different means and using advanced chemical
methods for water treatment if there is a possibility for water to be
affected by such pollution at certain regions.