The company that holds the concession to mine what it calls the third-largest potash deposit in the world says it has made significant amendments to its controversial Environmental Impact Assessment (EIA)...Environmentalists in Canada and Thailand have said this salt-waste stockpile, which would be taller than all but a few buildings in Udon Thani city, could contaminate soil and water supplies over a vast area...The company vehemently denies that its project will significantly damage either the land or the water in the area...APPC is 90-per-cent owned by Asia Pacific Resources (APR)...and 10-per-cent owned by the Thai government.