Orange County NC Website
;, ~ <br />,. Ultra Shallow Trench Conventional Systems are placed in areas with 24 inches or more of provisionally suitable chazacteristics ar <br />inch soil cap is placed over the trenches. <br />Shallow Trench Conventional Systems aze placed in azeas with 30 inches or more of provisionally suitable characteristics. <br />Conveational Systems are placed in areas with 36 i~acixes or more of provisionally suitable characteristics, <br />