a B ), ▁in ▁hydro logic ▁soil ▁group ▁B ▁ ▁Lim itations ▁c ited ▁in ▁the ▁" Build ing ▁S ites " ▁column ▁indicate ▁" slow ▁per me ability , ▁season al ▁high ▁water ▁table " ▁for ▁the ▁Cl A / h ydro logic ▁soil ▁group ▁C ▁area ▁and ▁" mod er ate ▁per me ability , ▁slight ▁ha z ard ▁of ▁ground water ▁cont am ination " ▁for ▁the ▁Wa A ▁and ▁Wa B / h ydro logic ▁soil ▁group ▁B ▁areas . ▁ ▁The ▁United ▁States ▁Department ▁of ▁Agricult ure ' s ▁So il ▁Conserv ation ▁Service ' s ▁" National ▁Engineering ▁Hand book " ▁describes ▁hydro logic ▁soil ▁group ▁B ▁as ▁" hav [ ing ] ▁moder ately ▁low ▁run off ▁potential ▁when ▁thoroughly ▁wet . ▁Water ▁transmission ▁through ▁the ▁soil ▁is ▁un imp eded . ▁Group ▁B ▁so ils ▁typically ▁have ▁between ▁ 1 0 ▁percent ▁and ▁ 2 0 ▁percent ▁cl ay ▁and ▁ 5 0 ▁percent ▁to ▁ 9 0 ▁percent ▁sand ▁and ▁have ▁lo amy ▁sand ▁or ▁sand y ▁lo am ▁text ures ." ▁The ▁work ▁describes ▁hydro logic ▁soil ▁group ▁C ▁as ▁having ▁" mod er ately ▁high ▁run off ▁potential ▁when ▁thoroughly ▁wet . ▁Water ▁transmission ▁through ▁the ▁soil ▁is ▁somewhat ▁restricted . ▁Group ▁c ▁so ils ▁typically ▁have ▁between ▁ 2 0 ▁percent ▁and ▁ 4 0 ▁percent ▁cl ay ▁and ▁less ▁than ▁ 5 0 ▁percent ▁sand ▁and ▁have ▁lo am , ▁sand y ▁cl ay ▁lo am , ▁cl ay ▁lo