All appeals are dismissed.

The costs of appeal are assessed against the plaintiffs.

The grounds of appeal are examined.

1. As to the remaining grounds of appeal by the plaintiffs except the plaintiff A

A. (1) Article 4(4) of the Urban Development Act provides that, in order to formulate a development plan for an urban development project in the replotting method, a person who designates an urban development zone shall obtain the consent of at least 2/3 of the land size in the area where replotting method is applied and at least 1/2 of the total number of land owners in such area, and the same shall apply to any amendment to a development plan to implement the replotting method, but the same shall not apply to any amendment to insignificant matters prescribed by Presidential Decree. The same shall apply to any amendment to the former Enforcement Decree of the Urban Development Act upon delegation from the authority.

(2) Article 7(1) of the former Enforcement Decree of the Urban Development Act provides that “Where the project cost of an urban development project increases to less than 10/100 of the previous total project cost, a modification shall be deemed a modification of minor matters, among the modifications that reflect the results of consultation on the environmental impact assessment under the Environmental Impact Assessment Act, the results of deliberation on the traffic impact analysis and improvement measures under the Urban Traffic Improvement Promotion Act, or the results of prior consultation on the examination of factors influencing disasters under the Countermeasures against Natural Disasters Act, notwithstanding paragraph (1) of the same Article.” (2) of the same Article provides that “Where the total project cost of an urban development project increases to less than 10/100 of the previous total project cost, a modification of the development plan shall be deemed a modification.” (2) The lower court does not provide that “where the total project cost of an urban development project increases to more than 10/100 of the previous total project cost” in any of the subparagraphs of Article 7(1) of the former Enforcement Decree of the Urban Development Act that provides for “matters not to be minor.”