8.1 megatons of kinetic energy. According to the Torino rating, only risk of “localized destruction” (less than “regional devastation”): https://cneos.jpl.nasa.gov/sentry/torino_scale.html
Earthquakes' energy doesn't all go to displacing water and hence generating tsunamis. An ocean impact is significantly more efficient at transferring energy into tsunamis.
https://www.sciencedirect.com/science/article/abs/pii/B97804...
https://web.archive.org/web/20100404013939/http://neic.usgs....
Asteroids mostly contain the same naturally radioactive elements we find in Earth's rocks - mainly potassium, uranium, and thorium in very small amounts. When they hit Earth, they don't typically create radiation hazards. Scientists have checked out famous impact sites like Meteor Crater in Arizona and found normal radiation levels. While impacts can briefly create some radioactive isotopes through the collision process, it's really the impact's explosive force that does the real damage, not radiation.
Just staying behind hill, will be not enough cover from shockwave, so people will suffer from fast pressure changes.
But shockwave quickly weakened as square of distance, and hill will make it's path longer. So, something like 100m hill could be considered as moving border of deadly zone 100m closer to epicenter.
[1] https://en.wikipedia.org/wiki/Tunguska_event [2] https://en.wikipedia.org/wiki/Chelyabinsk_meteor
I'm guessing there's still a lot of uncertainty.