Mainstay Engineering Group is supporting TerraPower Isotopes' new $450M facility in Philadelphia's Bellwether District.

Founded specifically to address the complex engineering demands of the Life Sciences and Pharmaceutical sector, Mainstay Engineering Group, Inc., a multi-disciplined engineering firm, has established a reputation for unparalleled expertise, uncompromising quality, and long-term, flexible solutions that meet the demands of the most challenging projects. This foundational focus has allowed us to become a recognized leader—the best in class—for mission-critical compliance and operational performance in a number of industries. Today, with five decades of deep technical expertise, Mainstay leverages these rigorous standards across all operations, serving as a trusted, strategic partner for not only the life sciences, biotechnology and pharmaceutical industries, but for complex industrial and manufacturing, science and technology, data centers, healthcare, energy, and other sectors where reliable, precision engineering is paramount to our clients’ and partners’ success. Our foundational success is evident in our vast portfolio, which spans the entire project lifecycle, from developing ground-up campuses and major facility expansions to complex adaptive reuse projects of existing facilities. Mainstay’s specialized teams have successfully executed projects in nearly every corner of the United States, with a significant concentration of work across the Northeast, Southeast, Midwest, and Central regions of the U.S. While we are licensed in all 50 states, our reach extends internationally, ensuring that our trusted engineering expertise supports our clients wherever their most critical operations are located. But our greatest testament isn’t a single project – it’s the enduring confidence of our partners. With over 90% of our work generated through referrals and repeat business, our clients continually return to Mainstay because they know precision, performance, and partnership are non-negotiable. View our current job opportunities at www.megr.com/careers.