Security Control Assessor

About the Job

Candidates must be a United States Citizen (no dual status) per contract requirements.

Main Sail is seeking experienced Security Control Assessors to support cybersecurity and accreditation operations for a National Nuclear Security client located in Oak Ridge TN.

Responsibilities:

• Implements and maintains security controls aligned with approved baselines and organizational requirements.
• Supports system authorization activities, including the development and maintenance of security documentation such as System Security Plans (SSPs) and Plans of Action and Milestones (POA&Ms).
• Monitors system security posture and identifies risks, vulnerabilities, and compliance gaps.
• Tracks and manages POA&Ms and coordinates remediation activities with system stakeholders.
• Assesses the security impact of system changes and supports configuration and change management processes.
• Supports continuous monitoring activities, including vulnerability management and security reporting.
• Serves as a security liaison between system teams, cybersecurity operations, and governance bodies.
• Prepares systems for security assessments, audits, and Authorizing Official reviews.

Required Experience:

• Level 3: Bachelor's Degree w/ 2-5 yrs responsibilities experience; or Associates Degree w/ 5-10 yrs experience.
• Level 4: Master's Degree w/ 2-5 yrs responsibilities experience; or Bachelor's Degree w/ 5-10 yrs experience; or Associates Degree w/ 10-15 yrs experience.
• Level 5: Master's Degree w/ 5-10 yrs responsibilities experience; or Bachelor's Degree w/ 10-15 yrs experience; or Associates Degree w/ 15-20 yrs experience.
• Firm understanding of NIST SP 800-37 and NIST SP 800-53; CNSSI 1253 experience a plus.
• Requires current active DoE Q; or DoW TS.

Location: Must reside within 50 miles of Y-12 Site, Oak Ridge TN

Period: 09/2026 - 09/2027 with possible extensions.