During the course of planning for and designing of four water treatment facilities
for the Seminole Tribe of Florida, disposal of the membrane reject water and other treatment
sidestream flows became an issue, due to extremely rigorous requirements
pertaining to environmental impacts. The plants for the four reservations, have
capacities ranging from 0.10 to 1.0 million gallons per day (mgd). Source water
comes from wells at each site, and membrane purification results in
concentration of dissolved constituents in the reject flows to between 4 and 5
times their original strength, depending on recovery. This stream, as well as the
initial startup well purge stream (to reduce and stabilize SDI) contained high
levels of hardness, minerals and miscellaneous dissolved and suspended
components. These waste streams required disposal, and were originally to be
processed through the wastewater treatment facilities (WWTF). However, an
absence of nutrient value, combined with the strength of dissolved constituents
would impose an unacceptable hydraulic and inert material load on the WWTFs,
and another alternative was sought.
The following alternatives were evaluated:
surface water (point) discharge;
land application as spray or percolation;
subsurface disposal by deepwell injection;
ocean outfall; and,
co-disposal with treated wastewater effluent.
Alternative evaluation included discussions with various regulatory agencies
concerning permitting viability, relative economic impact on overall project costs
and long term risks. The alternatives each had advantages and liabilities that
were evaluated before the final recommendation was made to the Seminole Tribe. Variations on land application were eventually selected at three of the four
sites, and the final site is still being evaluated.
| Edition : | Vol. - No. |
| File Size : | 1
file
, 260 KB |
| Note : | This product is unavailable in Ukraine, Russia, Belarus |
| Number of Pages : | 4 |
| Published : | 03/01/2005 |
