CHARLES D. SCOTT, PH. D.
              Environmental/Industrial Toxicologist
         May 30,2000
      COST OF SEDIMENT DISPOSAL FOR THE CITY OF WILSONVILLE
                  FOR THE WATER TREATMENT PLANT
            
            1.   Cost for conducting the TCLP testing on the sediment is taken from the
            2000-2001 Schedule of Fees from the Environmental Services
            Laboratory ($1180.00/test, plus 25 % add-on for the profit by testing
            firms) total of $1475.OO/ day for 15 MGD generated by the treatment
            plant.
            2.   Spencer Environmental Services have quoted $78.00/hour hauling fee,
            and indicated 3-hours per truck to haul to and from the landfill.  This
            comes to $468.00/day.
            3.   Spencer Environmental Services indicated that the cost of sediment
            disposal (Tipping Fee) Is $59.00/ton.
       Total estimated cost associated with the "Sediment" that will be generated by
       the treatment plant by producing 15 MGD. 2-truck loads of sediment (24
       tons/day) will be generated daily for 365 days year.
            4.   Each truck-load contains 12 ton of sediment x 2 truck-loads
     
                 Cost of testing each truck-load $1475/day x 365 days
                                        $538,375.00/year 
     
                 Cost of hauling to landfill $468 /dav x 365 days
                                        $170,820.0O/year
                 Cost of sediment disposal/landfill   $1416/day x 365days
                                        $516,840.0O/vear
     
                            Total Cost/day/year      $3359.00/day or $1,226,035.00/year.
                                                                                   
       
       Total estimated cost associated with the "Sediment" that will be generated by
       the treatment plant when producing 70 MGD, 8- truck loads of sediment (96
       tons) will be generated daily (365 days/year).
            5.   Each truck-load contains 12 ton of sediment x 8 truck-loads:
                            Cost of testing each truck-load  $2950/day x 365 days
                            $1,076,750.00/vear
                            Cost of hauling to landfill  $1872/day x 365 days
                            $683,280.00/year
                            Cost of sediment disposal/landfill   $5664/day x 365 days
                            $2,067,360.00/year
                             Total Cost/day/year $10,486.00/day or $3,827,390.00/year


       Total estimated cost associated with the "Sediment" that will be generated by
       the treatment plant by producing 120 MGD, 16-truck loads of sediment (192
       tons) will be generated daily (365 days/year).
       6. Each truck-load contains 12 ton of sediment x 16 truck- loads
                             Cost of testing each truck-load   $5900/day x 365 days
                             $2,153,500.00/year
                             Cost of hauling to landfill  $3744/day x 365 days
                             $131,040.00/year
                             Cost of sediment disposal/landfill  $11,328/day x 365 days
                             $4,134,720.00/year
               Total Cost/day/year $20,972.00/day or $6,419,260.00/year