ENERGY

Arco Expects Gain From Vastar Sale: The Los Angeles-based oil company said it will realize an after-tax profit of about $270 million from selling 17.7% of its Houston gas subsidiary, Vastar Resources Inc. Atlantic Richfield Co. sold 17.25 million shares of Vastar earlier this month for $28 each. The proceeds, to be reflected in third-quarter accounts, are to be used for general corporate purposes but not to pay debt. The company is also planning a $1-billion sale of debt tied to Lyondell Petrochemical Co., of which it owns 49.9%.