You are correct about the infrastructure. Nuclear security teams are similar to police SWAT units. Heavily armed (by Canadian standards), well trained and highly regulated.
Additional infrastructure requirements:
- Environmental monitoring.
- Emergency planning and response.
- Regulatory compliance.
- Training.
- Auditing and oversight.
- Radiation dosimetry and health physics.
- Radiation protection.
- Radioactive waste management (low, medium and high level).
- Document management.
A single unit nuclear generating station employs ~ 600 people.
The big stations (Pickering, Bruce, Darlington) employ many thousands. There is an army of contractors, engineers, technicians and trades that support the generating stations.
The regulatory requirements at a nuclear facility are HUGE. There is constant oversight and endless audits. Each audit produces findings each of which must be addressed and resolved (this can become an industry unto itself). The volume of documentation required is substantial: nothing happens without an approved procedure and work stops if the procedure can't be followed. All processes require extensive documentation to show the procedure was performed in accordance with approved procedures.