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Senior Mechanical Engineer

Mississauga, Ontario, Canada

Overview

AtkinsRéalis is one of Canada's largest private-sector nuclear engineering organizations, with more than 60 years of experience supporting the nuclear industry in Canada and globally. We deliver a comprehensive range of services across the nuclear lifecycle and are proud stewards of Canada's CANDU® nuclear technology.

Our nuclear business is experiencing strong growth, driven by a robust pipeline of refurbishment and new build projects. As part of this momentum, Candu Energy Inc., an AtkinsRéalis company, has partnered with Ontario Power Generation (OPG) to deliver the Darlington New Nuclear Project (DNNP). This landmark project is leading the deployment of the GEH BWRX-300 Small Modular Reactor (SMR), the first grid-scale SMR in Canada.

We are currently seeking a Senior Mechanical Engineer to join our growing engineering team. In this role, you will support major nuclear projects including the DNNP SMR program, providing technical expertise in mechanical and equipment engineering.

This position is based in Mississauga, Ontario, with opportunities for periodic site visits. This is a permanent, full-time position.

Your role

  • Perform engineering work in accordance with QA programs, codes, standards, and regulatory requirements.
  • Independently plan, execute, and deliver engineering assignments with minimal supervision.
  • Perform conceptual and detailed design of mechanical systems, including equipment layout, flow sheets, and component selection.
  • Prepare and review engineering deliverables including calculations, specifications, drawings, reports, and technical documentation.
  • Support equipment engineering activities including sizing, selection, and evaluation of pumps, heat exchangers, valves, pressure vessels, and related systems.
  • Interface with multidisciplinary teams, clients, and suppliers to resolve technical issues and ensure design integration.
  • Perform pre-order and post-order engineering support, including requisitions, technical evaluations, and vendor document reviews.
  • Provide engineering support during manufacturing, assembly, testing, and commissioning phases.
  • Conduct design reviews and participate in project planning, proposals, and cost estimating activities.
  • Provide technical guidance, mentorship, and oversight to junior engineers and designers.
  • Perform site visits, inspections, and walkdowns at client sites and supplier facilities.
  • Support construction and field execution activities, including design changes, revisions, and issue resolution.
  • Ensure delivery of engineering work within budget, schedule, and quality requirements.
  • Provide timely technical solutions to complex engineering challenges.
  • Design mechanical systems and equipment for nuclear and industrial facilities.
  • Analyze engineering problems and develop practical and technically sound solutions.
  • Coordinate mechanical engineering work with multidisciplinary teams.
  • Lead defined scopes of work within project environments.
  • Review engineering and vendor deliverables for quality and compliance.
  • Mentor junior engineers and provide technical leadership.
  • Resolve engineering issues throughout design and project execution phases.
  • Ensure compliance with QA programs and applicable codes and standards.
  • Deliver high-quality work on time and within budget.
Nuclear Engineering

Location

Mississauga, Ontario, Canada

Job Type

Full time

Ref

R-157707

Salary range

-

About you

Required Qualifications:

  • Engineering degree in Mechanical Engineering (or related discipline) from an accredited university.
  • Registered Professional Engineer (P.Eng.) in Ontario or eligible.
  • 8+ years of experience in mechanical or equipment engineering in nuclear or heavy industrial environments.
  • Experience in design and specification of mechanical equipment and systems (e.g., pumps, valves, heat exchangers, pressure vessels).
  • Experience preparing and reviewing engineering deliverables such as calculations, specifications, and reports.
  • Strong knowledge of applicable codes and standards (e.g., ASME, CSA, pressure boundary codes).
  • Ability to work independently and manage complex engineering tasks.
  • Strong communication and interpersonal skills.

Preferred Qualifications:

  • Experience in nuclear power plant projects (new build, refurbishment, or modifications).
  • Site experience in construction, commissioning, or manufacturing support.
  • Experience with nuclear pressure boundary codes (e.g., ASME Section III, CSA N285).
  • Experience with equipment qualification, seismic, or environmental requirements.
  • Prior experience mentoring junior staff or leading technical teams.
  • Knowledge of CANDU systems and design practices.
  • Familiarity with engineering change control (ECC) processes.

Skills & Competencies:

  • Strong technical expertise in mechanical and equipment engineering.
  • Problem-solving and analytical thinking.
  • Effective communication and technical writing skills.
  • Ability to work in multidisciplinary team environments.
  • Leadership and mentoring capabilities.
  • Strong organizational and time management skills.
  • Adaptability in fast-paced project environments.
Why choose AtkinsRéalis?

Why choose AtkinsRéalis?

Wherever you are in your career – and whoever you are – AtkinsRéalis is for you. Here, support and collaboration are a vibrant part of a culture that lets you choose where – and how far – your career can go. Take on projects that push boundaries and drive sustainable impact, surrounded by colleagues who believe there's no limit to how brilliant you can be. It's time to join a like-minded team where you'll be rewarded, supported, and free to be your kind of brilliant.

Rewards & benefits

Explore the rewards and benefits that help you thrive – at every stage of your life and your career at AtkinsRéalis in Canada.

Enjoy competitive compensation, employee recognition, and a brilliant range of flexible benefits you can tailor to your health, wellbeing, financial and lifestyle needs.

Make the most of diverse opportunities for training and professional development to grow your skills and expertise.

And take advantage of our hybrid working culture and generous time-off policies to balance a fulfilling career with your personal life.

Be rewarded. Find out more.

Souvik: A nuclear leader and mentor dedicated to shaping a sustainable energy future

Discover Souvik’s video: a nuclear leader and mentor dedicated to shaping a sustainable energy future.

Souvik: A nuclear leader and mentor dedicated to shaping a sustainable energy future

About AtkinsRéalis

About AtkinsRéalis

We're AtkinsRéalis, a world-class engineering services and nuclear organization. We connect people, data and technology to transform the world's'infrastructure and energy systems. Together, with our industry partners and clients, and our global team of consultants, designers, engineers and project managers, we can change the world. We're committed to leading our clients across our various end markets to engineer a better future for our planet and its people.

Find out more.

Additional information

AtkinsRéalis cares about your privacy. AtkinsRéalis and other subsidiary or affiliated companies of AtkinsRéalis (referred to throughout as "AtkinsRéalis") are committed to protecting your privacy. Please consult our Privacy Notice on our Careers site to know more about how we collect, use, and transfer your Personal Data.

By submitting your personal information to AtkinsRéalis, you confirm that you have read and accept our Privacy Notice.

Appropriate accommodation will be provided upon request throughout the recruitment and hiring process as required by Company policy and the Accessibility for Ontarians with Disabilities Act (AODA).

Successful applicants will be notified about AtkinsRéalis' accommodation policies at the time the employment offer is extended, and the information will be shared with new personnel during the onboarding process.

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