Fig. 4. Drying the waste before selling it as organic fertilizer
1.4. Deep pond. A small percentage of pig farmers,
who have very limited spare land, dump their pig
waste into a deep pond on their farms. These farms
are always located away from the neighborhood,
because the waste (which is left in the pond for
years) gives off a very bad smell. Therefore, the
local government has to enforce protective regulations
on these farmers.