Once the pump in the recirculating sand filer was started, TKN

concentrations within the septic tank, again a reliable indication

of Total Nitrogen concentration, declined almost immediately as can

be seen in Figure 4.4.    As in Site 1, no detectable amounts of

nitrates were found leaving the septic tank which indicates that

denitrifying bacteria are able to convert any nitrate entering the

septic tank to nitrogen gas.

     Figure 4.6 shows that the as of mid-December, approximately 12

mg/l of Total Nitrogen is exiting the denitrification system to the

mound system.     Conversely, Figure 4.4 shows that before the

recirculating sand filter was installed an average of 43 mg/l of

Total Nitrogen was being pumped to the mound system. This amounts

to a 72% decrease in Total Nitrogen leaving the system.

      As  can be   seen  in Figure   4.7, as   of mid-January   the

 temperature of the septic tank and pump chamber of the sand filter

 is around 140C. This is much higher than the temperatures at Site

 1 which   we  feel  is  due  primarily   to  the  facts  that  the

 recirculating sand filter at this site is located deeper in the

 ground and that this site presently has a much higher water usage

 than the other site. While these temperatures are higher than the

 temperatures at Site 1, they are still on the low range of

 temperatures reported for nitrification rates and thus may have an
 impact on the nitrification process before the winter is over.
      Groundwater samples have been taken at both sites a few times

 since the systems have been installed and started.    Presently, we

 are beginning to increase the monitoring schedule of groundwater