All appeals are dismissed.

The costs of appeal are assessed against the plaintiff (Counterclaim defendant).

The grounds of appeal are examined (to the extent of supplement in case of supplemental appellate briefs not timely filed).

1. As to the grounds of appeal Nos. 1 and 2, the obligation to assert and prove the completion of work in a contract for work is against a contractor seeking remuneration for the result of work (see, e.g., Supreme Court Decision 94Da26684, 26691, Nov. 22, 1994). In order to have the completion of work in a contract for the supply of crops, the fact that the last stage of work in the contract for the supply of crops ends is insufficient just because the main structure of the original and last stage is constructed as agreed upon and must have the performance generally required by social norms. Whether the last stage of work in an individual case has complied with must be objectively determined in light of the details of the contract for the supply of crops in question and the principle of trust and good faith, and thus, a contractor claiming remuneration for the supply of crops has to assert and prove not only the completion of the last process set forth in the contract for the production of the subject matter, but also the performance and certification that is generally required by social norms as agreed upon.

(2) The Plaintiff (Counterclaim Defendant; hereinafter “Plaintiff”) shall construct the main structure of the instant facility so that the average value and the value of the water discharged for 30 days after the completion of the operation of the instant facility meet the water quality standards of this case, as agreed upon in accordance with the special specifications. In light of the reasoning of the lower judgment, the lower court determined that the instant contract constitutes a production supply contract.