Marathon Oil has announced that construction of the $1.9 billion heavy oil upgrading project at its Detroit refinery is underway following issuance of an air quality permit by the Michigan Department of Environmental Quality.

With expected completion in late 2010, the project will increase the refinery’s total capacity from 102,000 barrels per day (bpd) to 115,000bpd, which will include an additional 80,000bpd of heavy oil capacity.

This increased refining capacity will supply more than 400,000 additional gallons of clean transportation fuels per day to the marketplace.

Gary Heminger, executive vice president of Marathon and president of the company’s refining, marketing and transportation operations, said: The Detroit heavy oil upgrade project is illustrative of strategic investments we are making across our downstream business to increase coking capacity, lower feedstock costs as well as increase efficiency and flexibility, so we can continue providing competitive returns in a challenging downstream environment.