All gas stations in Suffolk County must replace their single-wall tanks to double-wall tanks by January 1st, 2010. If you haven’t already done so, you must do it now, time is running out! Failure to upgrade by January 1st, 2010 will result in your gasoline business to be closed. Unlike Suffolk County, gas stations in Nassau County with underground storage tanks of 30 years and older must also meet the 2010 deadline. Also all single-wall tanks must be replaced with double-wall tanks within one year of the 30 years replacement timeframe.