Environmental stewardship, health, safety and corporate citizenship are core values of HollyFrontier. We are committed to minimizing environmental impacts by reducing wastes, emissions and other releases. We conduct our business with primary emphasis on the health and safety of our employees, contractors and neighboring communities.
We have invested over $300 million since the merger in 2011 in safety and environmental improvements, approximately 25% of annual capital expenditure. We have spent an additional $300 million on maintenance capital and risk reduction, improve both safety and reliability.