PERMFILE52017

• Permit No: C1981012A
• IBM Index Class Name: Permit File
• Doc Date: 11/16/2006
• Section_Exhibit Name: Section 2.05 Operation and Reclamation Plan
• Media Type: D
• Archive: Yes

• channel was estimated from a topographic map to be .017 ft./ft. Equation
3 gives 2.4 x 10-6 cfs and 4.2 x 10-6 cfs for the discharge through the
backfill, corresponding to stream discharges of 5 and 50 cfs,
respectively.
The leaching test data are used to estimate the chemical
composition of waters reentering the stream from the backfilled channel.
As explained in the discussion of the leach tests, the concentrations of
various species in the first increment of column effluent are those in
the antecedent pore solution. Thus, the concentrations listed in the
first column of Table 31, Results of Chemical Analysis, are those
expected in the first flush from the backfilled channel.
insofar as the rate of leaching observed in the column tests is
representative the rate that will occur int he field, the leaching curve
can be 'scaled up' to field conditions. The time, tl, at this a
particular concentration was observed in the lab test if converted to a
• field time, tf by the following:
tf = (Lf/L1 vl/vf) tl = Lf/vf (fltl/L1)
where:
tl = lab time
vl = seepage velocity in the lab tests
L1 = Length of flow path in the lab tests
Lf = Length of flow path in the field
of = Seepage velocity in the field.
The grouping of terms on the right of the second equality shows
that it is only necessary to multiply the lab pore volumes by the ration
Lf/Vf to obtain the corresponding field times.
On the basis of the above, Table 32, Time Variation of Quality of
Effluent From Backfill Channel, was prepared to indicate the expected
time variation o quality of waters leaving the backfilled channel and
entering the stream. The length of flow path in the field was estimated
to be 750 feet and the field seepage velocity was estimated by:
•
(Revised OS/11/~J4)
2.05-72