Each cement plant has its own dedicated limestone quarries, all of which have adequate access to highways and/or waterways. Limestone is delivered to our Louisville plant by barge, and to all other plants by truck. All our mines, with the exception of one, are surface mines, which are mined using open pit techniques. We have one underground mine serving our plant in Sugar Creek, Missouri. All our limestone reserves are located on properties that are in the production stage. All our quarries are close to our operating facilities.
As of March 31, 2026, we had 313.3 million tons of proven and probable limestone reserves, and 752.3 million tons of measured and indicated limestone resources, exclusive of limestone reserves. Approximately 80% of our total reserves are owned, and the remainder are leased. We do not consider any of our individual quarries to be material for disclosure purposes. All our individual locations have at least 25 years of reserves and resources, with most of our locations having in excess of 50 years.
Below is a summary of our limestone resources, exclusive of limestone reserves, serving each of our cement plants at March 31, 2026.
(1) Measured, Indicated, and Inferred resources are based on an initial assessment using average selling price assumptions ranging from $18.76 to $23.06 per ton depending on location and market.