In 2012, according to Bureau of Labor Statistics, the major earthmoving equipment are reported to have accounted primarily or secondarily for nearly 10% of fatalities on construction sites. This alarming statistics, together with the fact that the construction working environment is less structured and predictable than other industries, indicate the need for better coordination and management of equipment on earthwork sites. Location-based Guidance Systems (LGSs) have been introduced and implemented for improving high-precision earthwork operations. However, the state of practice in LGSs is limited to machine-level equipment management. In view of the LGSs ability to control the finest motion of earthwork construction equipment, there is a great potential to boost their applicability at the project level, where decisions about the equipment control are made based on the global consideration of a fleet rather than a local view of one single piece of equipment. Accordingly, the present paper aims to design a Multi-Agent System (MAS) architecture that combines LGS technology with advanced safety management methods to support the equipment operators on the construction site. A two-layer safety mechanism is proposed for the safety management in the MAS that enables proactive and reactive responses for the prevention of equipment-related collisions on the construction site. A case study is developed to validate the proposed method. It is found that the proposed MAS structure is able to effectively address the fleet-level coordination between earthwork equipment and potentially improve the safety of earthwork projects.