Associated Press: Cargo ships are avoiding the California coast because of tightened air pollution rules, causing problems for Navy missile tests. California Air Resources Board rules that went into effect last summer mandate that ships within 24 miles of the coast burn cleaner fuel. As a result, ships are staying farther at sea so they can burn dirtier, cheaper fuel. That has posed problems because the ships are now gathering in a spot where the Navy conducts missile tests. It has also caused …