Water quality assessment of open wells in and around Chavara industrial area, Quilon, Kerala.

Water quality of four open wells representing four localities around the Kerala Minerals and Metals Ltd industrial area, Chavara, Quilon district was studied fora period of six months from December, 2006 to May 2007 to assess the suitability of the well waters for domestic purposes. The well waters exhibited high BOD (average values from 12.87-15.96 mg l(-1)), COD (666.67-796.67 mg l(-1)), TDS (500-1466.67mg l(-1)), total hardness (110-835 mg l(-1)), nitrate (1.12-4.97 mg l(-1)), calcium (30.59-271.22 mg l(-1)), phosphate (0.19-0.48 mg l(-1)) and free CO2 (49.13-102.47 mg l(-1)) and low dissolved oxygen (2.63-3.13 mg l(-1)). Heavy metal analysis revealed that the third and fourth wells are free from heavy metal pollution. Coliform test showed bacterial contamination in all the wells. The values of BOD, COD, TDS and phosphate exceeded the maximum permissible limits and the dissolved oxygen was much lower than the desirable limit in all the well waters. Hence all the four well waters are found unsuitable for domestic purposes as it is confirmed by water quality index. The use of waters of open wells in and around the industrial area may cause health hazards to nearby inhabitants.