Exhibit 10(z) Den norske Bank Energy Finance March 11, 1996 Mr. Nicholas N. Carter President South Hampton Refining Co. P. O. Box 1636 Silsbee, Texas 77656 Via telefax, #409-385-2453 Dear Nick: This shall serve to inform you that Den norske Bank AS has approved an extension in the maturity of your loan to april 30, 1996. During this four-month extension period, a principal reduction in the loan balance of $100,000 will be required. Please let me know if you have any questions with respect to this extension. Sincerely, Byron L. Cooley Den norske Bank AS, Representative Office Three Allen Center, Suite 4890, Houston, Texas 77002 Telephone (713) 757-1281 -- Telefax (713) 757-1167