Valero L.P., formerly Shamrock Logistics, L.P., owns and operates most of the crude oil and refined product pipeline, terminalling and storage assets that support Valero Energy Corporation's (a subsidiary and customer of the Company) McKee, Three Rivers and Ardmore refineries, as well as its marketing operations located in Texas, Oklahoma, Colorado, New Mexico and Arizona. The Company generates revenues from its pipeline operations by charging tariffs for transporting crude oil and refined products through its pipelines. The Company also generates revenue through its terminalling operations by charging a terminalling fee to customers, primarily Valero Energy and its affiliates. The terminalling fee is earned when the refined products enter the terminal, and includes the cost of transferring the refined products from the terminal to trucks. An additional fee is charged at the refined product terminals for blending additives into certain refined products.