According to a Stanford publication, transporting uranium fuel requires reinforced containers. In several countries, armed guards escort nuclear fuel and nuclear waste. Disposal requires extensive shielding and very thorough storage since radioactivity from spent nuclear fuel is substantial for thousands of years.
In underwater drilling, ocean water mixes with drilling fluid. "Offshore Drilling," by Santa Clara University, points out that mechanical and chemical methods clean the water before pumping it back to the environment. Nevertheless, the process is imperfect. "Toxic zones" can develop around deep-sea rigs due to imperfectly cleaned ocean water. This is during normal operation, not oil spills.
A poorly built hydroelectric dam is cause for concern to downstream populations. Massive projects such as the Chinese Three Gorges Dam increase earthquake risk. A University of Alaska article expands on this topic. Piling enough water (or anything) eventually strains the planet's crust, making localized earthquakes more likely.