Senior OT Security Engineer

Job ID: 520178

Exempt

Oldcastle Infrastructure™, a CRH company, is the leading provider of utility infrastructure solutions for the water, energy, and communications markets throughout North America. We're more than just a manufacturer of precast concrete, polymer concrete, or plastic products. We're a trusted and strategic partner to engineers, contractors, distributors, specifiers, and more. With our network of more than 80 manufacturing facilities and more than 4,000 employees, we're leading the industry with innovation and a safety-first mindset.

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Job Summary

The Senior OT Security Engineer is responsible for securing manufacturing Operational Technology (OT) environments while preserving safety, reliability, and production uptime. This role supports traditional manufacturing operations by applying practical, risk-based cybersecurity controls to industrial control systems and plant networks.

The position sits within the IT / Cybersecurity organization and works closely with plant engineering and operations teams to secure legacy and modern OT systems without disrupting production.

Job Location

• This role will work hybrid out of our office in the Sandy Springs, GA area.

Job Responsibilities

OT Security in Manufacturing Environments

• Protect plant-floor control systems (PLC, SCADA, HMI) from cybersecurity threats while maintaining stable operations.
• Implement OT network segmentation, firewalls, and DMZs appropriate for legacy manufacturing environments.
• Define and support secure remote access for vendors and internal plant support teams.
• Ensure OT security controls are practical, documented, and support production uptime.

Risk, Compliance & Change Control

• Perform OT cybersecurity risk assessments focused on real manufacturing risks (downtime, safety, quality).
• Support regulatory, insurance, and internal audit requirements related to OT cybersecurity.
• Ensure OT systems follow IT change management processes adapted for plant operations.
• Document and track security risks, exceptions, and compensating controls.

Vulnerability & Incident Management

• Identify OT vulnerabilities and develop remediation plans that consider operational constraints.
• Coordinate patching, configuration changes, and mitigations during planned maintenance windows.
• Support OT-related cybersecurity incidents and investigations in coordination with IT security teams.
• Work with plants to implement lessons learned from incidents and near-misses.

Standards & Operational Discipline

• Develop simple, repeatable OT security standards suitable for traditional manufacturing sites.
• Maintain OT asset inventories, network diagrams, and security documentation.
• Review vendor and system integrator solutions to ensure they meet minimum security requirements.
• Support lifecycle planning for aging OT systems and end-of-support risks.

Collaboration & Plant Engagement

• Serve as a trusted cybersecurity partner to plant managers, engineers, and maintenance teams.
• Work closely with OT integration and IT infrastructure teams.
• Provide security guidance and education to plant personnel in practical, non-theoretical terms.
• Mentor junior engineers and promote consistent security practices across sites.

Job Requirements

• Bachelor's degree in Information Technology, Engineering, or equivalent experience.
• 7+ years of experience in OT, cybersecurity, or manufacturing environments.
• Hands-on experience securing industrial control systems in traditional manufacturing plants.
• Strong knowledge of industrial control systems (PLC, SCADA, HMI).
• Experience with OT networking and industrial protocols (Ethernet/IP, Modbus, OPC).
• Hands-on experience with firewalls, segmentation, and secure remote access in plant environments.
• Understanding of legacy systems and long OT asset lifecycles.
• Working knowledge of OT security standards (IEC 62443, NIST) applied pragmatically.
• Experience in multi-site, legacy-heavy manufacturing environments.
• Familiarity with IT security tools (SIEM, IAM) as they relate to OT.
• Certifications such as GICSP, IEC 62443, CISSP, or CCNA Security.
• Experience working through plant outages, maintenance shutdowns, or brownfield upgrades.
• Strong operational mindset with respect for plant uptime
• Risk-based decision making over theoretical security models
• Ability to communicate clearly with non-IT plant personnel
• Calm, disciplined approach in high-impact production environments

What CRH Offers You

• Highly competitive base pay
• Comprehensive medical, dental and disability benefits programs
• Group retirement savings program
• Health and wellness programs
• An inclusive culture that values opportunity for growth, development, and internal promotion

About CRH

CRH has a long and proud heritage. We are a collection of hundreds of family businesses, regional companies and large enterprises that together form the CRH family. CRH operates in a decentralized, diversified structure that allows you to work in a small company environment while having the career opportunities of a large international organization.

If you're up for a rewarding challenge, we invite you to take the first step and apply today! Once you click apply now, you will be brought to our official employment application. Please complete your online profile and it will be sent to the hiring manager. Our system allows you to view and track your status 24 hours a day. Thank you for your interest!

Oldcastle Infrastructure, a CRH Company, is an Affirmative Action and Equal Opportunity Employer.

EOE/Vet/Disability

CRH is an equal opportunity employer. All qualified applicants will receive consideration for employment without regard to race, color, religion, sex, sexual orientation, gender identity, national origin, age, disability, status as a protected veteran or any other characteristic protected under applicable federal, state, or local law.

Client-provided location(s): Atlanta, GA

Job ID: CRH_FGB-520178-en_US

Employment Type: OTHER

Posted: 2026-02-14T19:19:50