The uranium isotopes 238U, 235U and 234U are foundnaturally in the environment. 238U and 235U are parent nuclides of twoindependent decay series of isotopes, while 234U is a member of the238U decay chain. When decay series occur in a closed system the series tendsto reach, with time, the state of secular equilibrium in which the activities of all seriesmembers are equal to the activity of its first nuclide. The activity ratio234U/238U in natural uranium may vary as a consequence of decaychain disequilibrium due to alpha recoil and biogeochemical processes. A study based onmeasurement of uranium concentration and 234U/238U activity ratios insoil samples collected from Nalgonda district, Andhra Pradesh, India, a proposed miningsite, was carried out to find the spatial distribution of uranium and the state of secularequilibrium of 234U/238U to examine the possibility of applyinguranium concentration and uranium isotopic activity ratios to detect any hydrogeochemicalchanges in the environment during/post-operation. Soil samples were collected and analyzedfor uranium concentration using the conventional UV fluorimetric method, showing a uraniumconcentration in the range of 0.7 ± 0.2 ppm to 7.9 ± 0.4 ppm with an average of 3.4 ppm, and234U/238U activity ratios were estimated using the alphaspectrometry technique, showing an activity ratio in the range of 0.92 ± 0.11 to1.02 ± 0.11. The 234U/ 238U activity ratio obtained indicated thatthese two uranium isotopes are in the state of secular radioactive equilibrium. The percentactivity ratio of 238U/total U and 234U /total U is observed to varyfrom 47.94 ± 4.83 to 50.76 ± 4.87 and 45.80 ± 3.83 to 49.14 ± 3.99, respectively.