1. The Defendant’s KRW 565,338,811 to the Plaintiffs and 15% per annum from April 27, 2019 to May 31, 2019.

1. Basic facts

A. 1) The Defendant entered into the instant contract, etc., with the Daejeon Regional Procurement Service “C” (hereinafter “instant construction”).

(2) The Daejeon Regional Procurement Service requested the conclusion of a contract on the instant construction project, and the Daejeon Regional Procurement Service announced the tender of the instant construction project by means of a tender document around December 2013. 2) The Plaintiffs organized a joint supply and demand organization with a share of 52% and 48% shares of Plaintiff A, B, and received the award of the instant construction project.

3) On January 16, 2014, the Plaintiffs concluded a contract on the instant construction work with the Defendant for the construction period as “from January 17, 2014 to December 31, 2016 (the total number of construction days)” and the contract amount as “9,721,707,000 won” (hereinafter “instant contract agreement”).

B. The construction of this case and the bill of quantity error 1) The construction of this case is to remove all existing ground buildings in the site of this case and to install structures to store rainwater in the underground by deep digging the site in order to prevent flood occurrence due to heavy rain. The construction of household facilities (such as soil shield, and installation of household facilities in parallel with the excavation file, H-book) are to be carried out in the order of the installation work of household facilities (the installation work of household facilities such as tamp file and H-book), the construction work of structures (main work), the dismantling work of household facilities.

In order to prevent the earth collapse of the excavated part from the excavation of land to the time underground structures are installed, he/she shall install a twit file in the outermost part of the excavated part, and install a H-book in the shape of shooting in the underground part where a structure is to be installed in order to cover the pressure of vertical and horizontally.

The site photographs of a construction site in which a set file or H-book is installed shall be as follows:

2) The bill of quantity of materials presented by the Defendant (hereinafter “the bill of quantity of materials of this case”) at the time of the public tender notice.

(3) The first schedule submitted by the Plaintiffs to the Defendant is the facility. The first schedule submitted by the Plaintiffs is the facility.