Pal-dang watershed is the only source water for more than 20 million people and industries in the Seoul-Kyungki metropolitan area. In 1999, some areas surrounding Pal-dang Lake were designated as protected areas by a special law, not allowing entry of any industry discharging specified materials such as Cu, Pb, As, and Hg. At that time, D-Electronics Co. did not have any manufacturing lines and any future plan to have new lines releasing such materials. However, the recent market environment of the semiconductor industry forced D-Electronics Co. to bring in a new manufacturing line which will release Cu in effluent. Because of the special law, D-Electronics Co. proposed a zero discharge system (ZDS) specially targeting removal of Cu and requested Ministry of Environment (MOE) to approve its expansion plan. But, MOE rejected the request with reasons such as unexpected accidents, possible illicit operations, absence of legal basis, and equity among industries. On the contrary, as well as other groups, the Ministry of Commerce, Industry and Energy (MOCIE), arguing a possible huge contribution of the expanded plant to national economic growth, demanded MOE to reexamine the reject and to reconsider it as a special exception. Right now, the case is being reconsidered under the affirmative atmosphere. Even if conservation is very important, since the source water is for more than 20 million people and many industries, this case illustrates a lesson that water conservation cannot compete with the demand for economic growth, at least, in Korea. Includes 5 references, tables, figue.