Concentrations of Natural and Manmade Radionuclides for Wadi Al Numan Area in Makkah Al-Mukarramah Province

Umm al Qura University buildings are situated in Wadi Al Numan area in Makkah ALMukarramah province. Therefore, a detailed study of this area is of great importance in future. The study area was divided to 15 parts and soil samples were sampled from each part. In situ, gamma Scout system was applied during sampling, to give the dose rate μSv/h at each point, which ranged from 0.08 to 0.22. For determination of radioactivity concentrations of the 226Ra, 232Th series and 40K, an in situ gamma spectrometer based on NaI(Tl) crystal crystal detector was applied. The concentrations (in ppm) ranged from ND to 2.4 , from 1.4 to 6.9 f, and from 1.7% to 3% for 226Ra, 232Th series, and 40 K respectively. An XR-D spectrometer was used for the mineral compositions analysis of the soil samples and Atomic Absorption Spectrometer was used for measuring mineral concentrations of K, Al, Bi, Pb, and Th in both percentage and (ppm). The mineral concentrations percentage ranged from 7.66% to 8.49% for Al and from 1.77% to 2.81% for K. The concentrations (in ppm) ranged from 10.0 to 21.81 for Bi, from 15.54 to 25.88 for Pb, and from 1.0 to 5.5 for Th. For measuring radioactivity concentrations of collected soils in Bq/kg for 226Ra, 232Th series, and 40 K, prepared dry weight samples were analyzed by a gamma spectrometer based on HPGe crystal detector. Soil samples collected are divided into two groups, sandy mud (silty sand) and a mixture of sand and clay (sand clay mixture). For silty sand the concentrations in Bq/kg dry weight ranged from 9.2 to 14.1 with average value 11.6, from 9.5 to 15.2 with average value 12.5, and from 378.2 to 557.8 with average value 481.3 for 226Ra,232Th series, and 40K respectively. The surface concentrations in Bq/m^2 for 137Cs ranged from LDL to 31.4 with average value 26.9.For sand clay mixture the concentrations in Bq/kg dry weight ranged from 10.1 to 18.1 with average value 13.3, from 11.1 to 22.6 with average value 15.6, and from 454 to 592 with average value 5143 for 226Ra, 232Th series, and 40K respectively. The surface concentrations in Bq/m^2 for 137Cs ranged from LDL to 164.1 with average value 83.3. The concentrations were compared with concentrations of isotopes of the same types of soil of similar research previously published.