Pros
These are really dependent on the office you are at, but some consistent themes are the strong focus on safety, options for work-related travel, and some interesting projects. I see some reviews complaining about work/life balance, but if you don't make that a priority, then your company surely will not either.
Cons
The overtime structure is confusing and honestly not applicable if you do not work 50+ hours per week. Upper management (again, this is dependent on the office you are in) often low-balls project budgets just to get business, which is counterproductive when the project inevitably goes over-budget. The pay is on the low-side of the acceptable starting salaries for Civil Engineers. I think the most important of all is a lack of a formal mentoring program. I think Terracon adopts a "sink or swim" approach. A formal mentoring program would greatly benefit a new engineer and give them guidance on transitioning from the academic realm to the professional.