Amentum is seeking a highly organized, detail-oriented, and proactive Administrative Assistant III/Office Administrator to provide comprehensive administrative and operational support to our team at Naval Air Station Fallon.  This role is critical to ensure smooth day-to-day office operations, supporting travel and expense processes, managing office supplies, and assisting with employee onboarding and compliance requirements. The ideal candidate will build strong relationships across the organization, work effectively with employees and leadership, and maintain accurate documentation to support audits, governance, and security protocols. This is an opportunity to contribute to a mission-driven environment, supporting operational excellence in a fast-paced and regulated industry.

Key Responsibilities:

• Coordinate and manage the maintenance team travel detachment trip reservations, processing expense claims, and monthly reconciliations.
• Oversee office supply inventory levels and reordering as necessary.
• Coordinate with external vendors, including copier maintenance, telephone, and internet service providers.
• Process and track invoices for site expenses, maintaining accurate and timely records for reconciliation.
• Maintain effective records and file management.
• Build and foster strong relationships across departments for seamless information flow and resolution of issues.
• Coordinate and organize logistics for on-site audits, reviews, and inspections, ensuring documentation and office setup are complete.
• Maintain office readiness for leadership visits, customer meetings, audits, and interactions with external stakeholders.
• Provides ad hoc administrative support, coordination, and project management as needed by company leadership.
• Manage competing priorities, anticipate challenges, and ensure tasks align with high value organizational objectives.
• Coordinate meetings, prepare agendas, track actions, and follow up on key outcomes.
• Draft and edit communications, reports, presentations, and executive-level submissions with high-level accuracy and professionalism.
• Maintain organized and up-to-date controlled records, registers, and documentation in line with company policy and internal management systems.
• Support compliance audits, inspections, and reviews.
• Handle sensitive and confidential information with a high level of discretion, professionalism, and sound judgment.
• Assist with employees onboarding and offboarding processes, ensuring necessary documents are completed and requirements are met.
• Support HR Business Partner and EHS Manager with processing workers’ compensation documentation, in compliance with state regulations.
• Other duties as assigned.

Required Qualifications:

• At least 3-5 years of related experience in administrative, clerical, or receptionist work.

• Exceptional organizational skills with the ability to balance multiple priorities effectively in a fast-paced work environment.

• Strong administrative support experience working with senior leaders, internal teams, and external customers.

• Advanced  proficiency in Microsoft Office Suite Outlook, Word, Excel, PowerPoint, and Teams.

• Professional, clear, and concise communication skills, both written and verbal.

• Working knowledge of routine operating office equipment (e.g., fax machines, copiers).

• Proven ability to work independently, maintaining clear alignment with organizational goals and senior leadership expectations.

• Careful attention to detail while considering the broader organizational impact of tasks.

• Strong discretion and judgment when handling sensitive and confidential information.

Preferred Qualifications:

• Familiarity with the Defense Travel System (DTS) and timekeeping management systems.
• Experience working in a regulated industries such as Defense, government, engineering, or professional services. 
• Understanding of Department of Defense (DoD) security protocols, including functions like badging and visit request processing.
• Current DoD Secret (or higher) security clearance.

Security & Clearance:

• Ability to obtain and maintain a U.S government security clearance. Note: US Citizenship is required to obtain a U.S government security clearance.
• High School diploma or equivalent.
• Ability to work all assigned shifts and schedules as needed.
• A valid driver’s license is required.

Work Environment:

• This position is based in office/on-site and aboard Naval Air Station Fallon Nevada.

Compensation Details:

The compensation range or hourly rate listed for this position is provided as a good-faith estimate of what the company intends to offer for this role at the time this posting was issued. Actual compensation may vary based on factors such as job responsibilities, education, experience, skills, internal equity, market data, applicable collective bargaining agreements, and relevant laws.

Benefits Overview:

Our health and welfare benefits are designed to support you and your priorities. Offerings include:

• Health, dental, and vision insurance

• Paid time off and holidays

• Retirement benefits (including 401(k) matching)

• Educational reimbursement

• Parental leave

• Employee stock purchase plan

• Tax-saving options

• Disability and life insurance

• Pet insurance

Note: Benefits may vary based on employment type, location, and applicable agreements. Positions governed by a Collective Bargaining Agreement (CBA), the McNamara-O'Hara Service Contract Act (SCA), or other employment contracts may include different provisions/benefits.

Original Posting:

Amentum anticipates this job requisition will remain open for at least three days, with a closing date no earlier than three days after the original posting. This timeline may change based on business needs.

Amentum is proud to be an Equal Opportunity Employer. Our hiring practices provide equal opportunity for employment without regard to race, sex, sexual orientation, pregnancy (including pregnancy, childbirth, breastfeeding, or medical conditions related to pregnancy, childbirth, or breastfeeding), age, ancestry, United States military or veteran status, color, religion, creed,  marital or domestic partner status, medical condition, genetic information, national origin, citizenship status, low-income status, or mental or physical disability so long as the essential functions of the job can be performed with or without reasonable accommodation, or any other protected category under federal, state, or local law. Learn more about your rights under Federal laws and supplemental language at Labor Laws Posters.