Environmental geochemistry of surface and subsurface water from Dera Ismail Khan division,Khyber Pakhtunkhwa,Pakistan

The dera ismail khan division is situated in the southern most part of the khyber- pakhtunkhwa province in pakistan. majority of population in this region obtain domestic water from tube wells,dug wells,ponds,stored run off of the indus and gomal rivers and perennial streams. this study is aimed to determine the physio-chemical contaminants in the surface and subsurface water which could cause environmental problem. for this purpose,representative water sample were collected from tube wells,dug wells,streams and rivers. these analyses were performed using hach dr/2000 spectrophotometer and graphite furnace atomic absorption spectrometer. chemically both surface and subsurface water samples of the area were classified as alkaline fresh water. the comparison of the data with standard limits set by word health organization (who) for drinking water suggested that in certain areas of the division,the drinking water samples have high concentrations of total dissolved solids,no 3 2-,so 4 2-,f -,cl -,fe 2+,ca 2+,mg 2+,pb 2+,ni 2+ and cd 2+ while ph,ec,hco 3 -,po 4 3-,na +,mn 2+,k +,cr 3+ and zn 2+ were within the permissible limits. these contaminations could be attributed to the geogenic sources which might be responsible for the health related problems in certain areas of the division.