Retrieve ID from web config

Hi all, Any idea on how to get the web form right? 

Originally, the webform will read from the database the standard approval email, i want to change the webform to read my email instead which is in the same table but not set as the default approval email for that department.

Database has - email, dep, approveLevel

In Web.Config - 

<add key="debugMode" value="true"/>
<add key="debugEmail" value="email@hotmail.com"/>

In Web Form aspx -

if (Convert.ToBoolean(ConfigurationManager.AppSettings.Get("debugMode")) == true)
            {
                leaveItem.Employee = ConfigurationManager.AppSettings.Get("debugEmail").ToString();
      ...