The removalof dams remains controversial because of high restoration costs, loss of low-cost electricity, and the loss of water storage facilities.
大坝的拆除仍然存在争议，因为高重建成本，损失低成本电力，以及损失蓄水设施。
2
Although removalof excessive fluoride from drinking-water may be difficult and expensive, low-cost solutions that can be applied at a local level do exist.
Removal or amendment of a control procedure may not significantly increase the risks associated with the operation of the system and may result in cost savings.