 Growth of local industries soon proved a mixed blessing.Serious pipeline and petrochemical plant accidents happened in 1960, 1964, and 1965.A 1985 explosion at one of the plants threatened the entire salt dome on which the city was built, which had in recent years been used to store liquid petroleum gas, and led to a series of efforts by townspeople to force the petrochemical industries to buy out the homes in the immediate vicinity of their plants.