4 MASS, EXPERIMENT STATION BULLETIN 446 



Collection of effluent samples was made from wells provided on the disposal 

 lines as indicated in diagram I. These wells were double "T" joints set with 

 one arm vertical. The lower portion of each vertical arm was plugged with 

 cement to provide a sump, while the upper portion extended up to the surface 

 of the ground and was open at the top. A cross section of the collecting wells is 

 shown in diagram II. 



v/ 



Diagram I. Plan of Septic Tank Installation and Disposal Field. 



X, line from sewer main. 

 R, receiving chamber. 

 T, septic tanks. 



N, north tank, 8 hours retention. 



M, middle tank, 12 hours retention. 



S, south tank, 24 hours retention. 

 W. collecting wells. 

 A, B, C, D, E, disposal lines. 



OPERATION OF TANKS 



Operation of the tanks was begun in September, 1943, and was continued until 

 hard freezing weather and snow in late December made it necessary to discon- 

 tinue. No data from that period are included in this report because operation 

 was in the experimental stage and a certain amount of trial-and-error procedure 

 •was required to detect faults in construction and to make plans to remedy them. 



