Distribution Model of Heavy Metals Discharged by Industries and Their Impact on Water Economic Value (Case Study at Cakung Dalam River, Rorotan-Marunda, North-Jakarta)

Abstract

Cakung Dalam river has received pollutants discharged by industries, including heavy metals. Hg, Cd, and Pb are heavy metals which very toxic in the world and their impact from generation to generation. The research was aimed : to determine the distribution level of heavy metals (Hg, Cd, and Pb); to developed distribution model of heavy metals; to calculate water economic value ; and to developed evolution model of water economic value . The distribution level of heavy metals were compared with standard values; the water economic value was determined by total economic valuation; the distribution model of Hg, Cd, and Pb, and the evolution model of water economic value were developed using Powersim 2.5c, MS. Exce l, SPSS 10.05, and Minitab. Validation of the models carried out by implementing theoritical test, structure stability test, consistency test, AME test, AVE test, Kalman filter test, U-Thelil’s test, and DW test. In 2003, the distribution level of heavy metals in river water, ground water, paddy, rice, and fishes are sign that Hg of river water was above standard value of group-C water (PP RI No. 82, 2001). It is not suitable to support fisheries and poultry. The distribution model of heavy metals showed increasing trend in the second half year in river water and ground water, and every half year in paddy, rice, and fishes. Over a 50 year period, the Hg, Cd, and Pb are predicted to increase by 0,012 ppm, 0,0029 ppm, and 0,0013 ppm in river water respectively; 0,01808 ppm, 0,08771 ppm, and 0,19150 ppm in ground water respectively; 0,0072 ppm, 0,0041 ppm, and 0,0069 ppm in paddy respectively; 0,0041 ppm, 0,0042 ppm, and 0,0084 ppm in rice respectively; and 0,0079 ppm, 0,0097 ppm, and 0,0056 ppm in fishes respectively. The water economic value in 2003 without heavy metals input was Rp 1.094.961.301,52. The evolution model of water economic value is predicted to decrease gradually : for 2003-2010, due to toxicity crustacea by Hg on river water; in 2010, due to Cd on ground water was above standard value of cleaning water; in 2028, due to Hg on river water was above standard value on agricultural water; and since 2032, due to river sedimentation. The water economic value by 2050 (January) is predicted Rp 337.336.753,73.