CHARACTERISTICS OF POLLUTANTS FROM UNDERGROUND STORAGE TANK LEAKAGE IN SOCIAL GAS STATION IN CHENGDU PLAIN

The leaky organic pollutants from underground storage tank in social gas station in Chengdu Plain were screened by stratified filter method． Based on the characteristic of Chengdu Plain and earlier research status，TPH，PAHs，BETX，MTBE， 1，2 -DCA and EDB were preliminarily selected as the characteristic pollutants． Based on the detection rate and content of each pollutant firstly，and the features of each pollutant secondly，TPH、PAHs and BETX were chosen as the compulsory indictors in monitoring，and suggested to be focused on periodically when monitoring underground storage tank leakage; MTBE could be taken as the optional indicator; 1，2 -DCA and EDB as compulsory indictors in monitoring social gas station built more than 20 years in Chengdu Plain．