SETTL ING PONDS 



It is necessary to wash gravel if the mined material has an appreciable 

 silt content. When gravel is washed, it is essential that settling ponds be 

 provided to allow silt to settle out before the wash water re-enters the 

 river. These ponds should be of sufficient capacity to handle the daily 

 volume of wash water or stream flow, or both, considering the settling 

 velocity of the entrained silt particles. Design considerations for settling 

 ponds can be found in Appendix F of the Guidelines Manual. 



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