The plaintiff's claim is dismissed.

Litigation costs shall be borne by the plaintiff.

(b) up to September 14, 200, concluded a subcontract with the content of sewage supply as KRW 11,973,500 (including value-added tax);

The main contents relevant to this case in the above subcontract shall be as follows:

【Special Conditions for Estimated Implementation of the Subcontract (Contract)” (hereinafter “Special Conditions for the Contract of this case”)

(2) The term “instant subcontract” includes construction specifications, etc. (hereinafter collectively referred to as “instant subcontract”). The standard subcontract agreement for construction business (basic)

1. The project owner: The contracted name of the Korea Rail Network Authority: C works;

2. Title of subcontracted construction: Earth and reinforced concrete construction works (excluding bridges).

3. The construction site: The construction site shall be one of the F Workers in Chungcheongnam-si, Chungcheongbuk-do.

4. Period of construction: September 14, 2019, the completion of construction on August 26, 2016.

5. Contract amount: The price for supply of KRW 11,973,500,000,0000 per day (11,973,50,000): One hundred and eighty million won per day (10,885,000,000) labor cost per day (3,100,0000,0000 won per day) * Value-added tax on labor cost under Article 84 of the Enforcement Decree of the Framework Act on the Construction Industry * KRW 1,00,000,0000 per day (1,08,500,000,0000) (2) The subcontract price shall be reasonably adjusted after consultation with the prime contractor on the change in the contract, if necessary to adjust the subcontract price due to the change in the contract contents, period, construction volume, etc.

Provided, That the principal contractor shall settle and pay the part already performed by the subcontractor before the details of construction are changed:

Article 3 (Additional Works) (1) Where a principal contractor deems it necessary to perform additional works other than this contract, he/she shall issue a document related to the additional works to a subcontractor before the subcontractor commences such additional works.

(2) The date of entrustment, details, subcontract consideration, terms and conditions of entrustment, etc. of a project shall be determined in additional documents.

(b).