Assistant Core Driller

Martin Marietta is seeking a motivated, safety-focused Assistant Core Driller to join the Exploration Services team based in Indianapolis, Indiana. The Assistant Core Driller supports the Core Driller in the safe and efficient transportation, setup, operation, maintenance, and demobilization of company drilling equipment and support vehicles during aggregate exploration and reserve development projects throughout the United States including both surface and underground mining operations.

This position serves as the primary developmental role within the drilling organization and provides hands-on training in drilling operations, geological sample collection, equipment maintenance, and field safety. The Assistant Core Driller works closely with the Core Driller to obtain high-quality geological data used to quantify and qualify mineral reserves while developing the technical, mechanical, and leadership skills necessary to advance to a Core Driller position.

This position involves extensive outdoor work in varying weather conditions, terrain, and operating environments. Frequent travel and overnight stays are required, with work rotations that may include up to fourteen consecutive days in the field before returning home. Travel time is paid at normal hourly rate and a Per Diem is provided for lodging and meals reimbursement. Applicants are required to operate DOT-regulated vehicles across state lines and, therefore, must be at least 21 years of age and maintain a current Medical Examiner's Certificate in accordance with applicable DOT regulations.

Responsibilities:

• Promote and uphold Martin Marietta's commitment to safety, environmental stewardship, and operational excellence.
• Assist with the transportation, mobilization, operation, and demobilization of diamond core drilling equipment, support vehicles, tooling, and auxiliary equipment.
• Support daily drilling operations under the direction of the Core Driller.
• Assist with rig setup, alignment, drilling fluid management, rod handling, core retrieval, and site housekeeping duties.
• Collect, photograph, label, package, document, and transport geological core samples and associated field data.
• Maintain core boxes and assist with sample handling procedures to ensure data quality and sample integrity.
• Perform routine inspections, preventative maintenance, cleaning, lubrication, and minor repairs on drilling rigs, vehicles, pumps, hydraulic systems, and support equipment.
• Assist with troubleshooting mechanical and operational issues to minimize downtime.
• Load, unload, secure, and transport equipment and materials in accordance with DOT requirements and company policies.
• Maintain accurate field records, sample inventories, maintenance logs, and project documentation.
• Maintain clean, organized, and safe work environments at drilling sites, shop facilities, and staging locations.
• Participate in pre-job inspections, hazard assessments, safety meetings, and training activities.
• Communicate effectively with Core Drillers, geologists, project managers, mine personnel, and other stakeholders.
• Develop the technical, operational, and leadership skills required for progression into the Core Driller role.

Qualifications

Required

• High school diploma, GED, or equivalent.
• Valid driver's license with a satisfactory driving record.
• Ability and willingness to obtain a Class A Commercial Driver's License (CDL).
• Ability to pass a pre-employment drug screening, background check, and DOT physical.
• Strong mechanical aptitude and willingness to learn drilling equipment maintenance and repair.
• Ability to work effectively as part of a team and follow direction from the Core Driller.
• Strong communication skills and a positive attitude toward learning and professional development.
• Ability to work 10 to 12-hour shifts in physically demanding environments.
• Ability to repeatedly lift and carry 50 to 75 pounds without assistance.
• Ability and willingness to work outdoors in all weather conditions and at surface and underground mining operations.
• Willingness to travel extensively throughout the United States and work multi-day field assignments.
• Reliable attendance history and demonstrated commitment to safety and professionalism.
• Ability to operate vehicles equipped with manual transmissions.

Preferred

• Previous experience in drilling, mining, construction, heavy equipment operation, mechanical maintenance, or related industrial environments.
• Experience towing trailers and operating commercial vehicles.
• Commercial Driver's License (CDL) or ability to obtain one quickly.
• Experience with diesel engines, hydraulic systems, pumps, and mechanical troubleshooting.
• MSHA Underground Miner certification or previous mining experience.
• Experience working in outdoor, industrial, mining, quarrying, geotechnical, environmental, or exploration drilling environments.