Dominion Virginia Power says it will not seek an increase in its base rates for at least two years. The utility says base rates make up about 60% of a typical residential bill and cover the company's non-fuel operational costs, salaries and part of its earnings. The utility proposed holding the line on the rates in its required every-two-year filing with the State Corporation Commission on Thursday. Dominion's base rates haven't been raised since 1992. The total bill for a typical customer using 1,000 kilowatt-hours is a little over $107. A roughly $1 increase in bills will take effect next month in order to cover an increase in the cost of four separate power projects.