544 the federal government provides disaster

5.44 The Federal Government provides disaster insurance that helps people to build
vacation homes in places subject to flooding, such as sand dunes. Assume the
government wants to protect the environment by preventing construction of homes
on a specific sand dune near the ocean. If the government takes private property on
the sand dune, either by condemning it or by imposing regulations that forbid any
construction, should compensation include or exclude the increase in the value of the
land caused by government flood insurance?
Article: Boomer vs Atlantic Cement
a) Is the externality in Boomer private or public?
b) Are the transaction costs of bargaining among the parties low or high?
c) Suppose the households had a right to order the cement company to stop polluting.
What obstacles would the cement company face if it tried to purchase the right to
produce from the households?