The statistical value of life in the US, which is applicable to small diffuse risks, is ~$10M. When the NHTSA or EPA or whatever decide whether to spend money on clean up a river to reduce cancer risks or impose safety rules, they use that amount (to first order). If someone is willing to pay p*$50M for a p<<1 chance of killing a member of the general public, the gov't can allow them and then spend that money saving lives, leading to both net lives saved and additional freedom/flexibility.
