1. The plaintiff's claim is dismissed.

2. The costs of lawsuit shall be borne by the Plaintiff.

1. Basic facts

A. The instant construction contract was concluded by the Korea Environment Corporation. (1) The Defendant was awarded a contract with the Korea Environment Corporation for the business of stuffing sewage treatment plants and undergroundization of sewage treatment plants in the Hanyang-si, and on June 5, 2015, “construction work for the business of undergroundization of stuffing sewage treatment plants in the Hanyang-si” (hereinafter “instant construction work”).

) Contract amount of KRW 3,693,580,00, contract amount of KRW 10% (369,358,000) of contract amount, contract amount of KRW 10% of contract amount of KRW 369,358,00) and contract period of construction from June 5, 2015 to January 9, 2017 (hereinafter “instant contract for construction”).

(2) The Plaintiff and the Defendant agreed on November 18, 2015 to change the contract amount of the instant construction contract into KRW 3,729,880,000 according to the change of the original contract.

3) On June 5, 2015, the Plaintiff issued a subcontract guarantee (369,358,000) from the Construction Mutual Aid Association and submitted it to the Defendant. On December 1, 2015, the Plaintiff issued a subcontract guarantee (3,630,000) from the Construction Mutual Aid Association and submitted it to the Defendant. In addition, on June 12, 2015, the Plaintiff issued a subcontract guarantee (154,000,000) from the Construction Mutual Aid Association and submitted it to the Defendant. On August 5, 2015, the Plaintiff received a subcontract advance payment guarantee (201,30,000,000 from the Construction Mutual Aid Association) from the Defendant, and received advance payment of KRW 35,30,000 from the Defendant.

Article 22 (Advance Payment) ① A (Defendant) of the General Terms and Conditions of Contracts for Construction Works shall pay advance payment to B, as stipulated in the contract.

(2) Where a person placing an order receives an advance payment from the person placing an order, the agreement shall be stipulated within the extent of 15 days from the date on which he/she received such advance payment (or the date he/she received an advance payment before making an entrustment) so that he/she may commence his/her construction works, in accordance with the details and ratio of the advance payment.