improving stockyard efficiency, but has also given rise to a new and intriguing class of scheduling problems that has proven to be surprisingly rich. One reason is that the travel time of the reclaimers, i.e., the time between the completion of the reclaiming of one stockpile and the start of the reclaiming of a subsequent stockpile, cannot be ignored. Another reason is the interaction between the two reclaimers, caused by the fact that they cannot pass each other.

The remainder of the paper is organized as follows. In Section \[sec:background\], we provide background information on the operation of a coal export terminal and the origin of the reclaimer scheduling problem. In Section \[sec:lit\], we provide a brief literature review. In Section \[sec:problem\], we introduce the abstract model of the reclaimer scheduling problem that is the focus of our research and we introduce a graphical representation of schedules that will be used throughout the paper. In Sections \[sec:without\] and \[sec:with\], we present the analysis of a number of variants of the reclaimer scheduling problem. In Section \[sec:final\], we give some final remarks and discuss future research opportunities.

Background {#sec:background}
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The Hunter Valley Coal Chain (HVCC) refers to the inland portion 