HYDRO27562

• Permit No: C1982056
• IBM Index Class Name: Hydrology
• Doc Date: 3/31/1998
• Doc Name: AUTHORIZATION TO DISCHARGE UNDER COLO DISCHARGE PERMIT SYSTEM
• Permit Index Doc Type: NPDES
• Media Type: D
• Archive: No

:ART I
Page 3 of 14
D
FOOTNOTES
g/ Where, based on a minimum of 5 samples, the permittee demonstrates to the satisfaction r`
the Water Quality Control Division that the level of total dissolved solids (TDS) in th-
effluent can be calculated based upon the level of electrical conductivity, the permitt~.,
may measure and report TDS in terms of electrical conductivity.
J TDS shall be sampled on a monthly basis until six samples have been analyzed. A report ~~
"No Discharge" shall not be counted as one of the six samples. Thereafter, monitoring shat
continue on a quarterly basis. Following submittal of the initial six sets of monthly dot:
the Division shall determine whether the permittee is required to submit a report addressii_
salt removal in accordance with Regulations For Implementation of the Colorado Rive
Salinity Standards Through the NPDES Permit Program, 3.10.0. If the salinity report :'•
required, the Division shall so advise the permittee by letter and the report shall 1
submitted within 180 days.
J This parameter is subject to "Noncompliance Notification" requirements of Part II.A.3.(b)(~'
of this permit.
1./ Procedure for determining settleable solids is contained in 40 CFR 434.64. The meths
detection limit for measuring settleable solids under this part shall be 0.4 ml/1.
~c/ Should a precipitation event occur, the permittee shall submit appropriate documentation is
order for an exemption to be claimed (see Burden of Proof requirements). In lieu of suc:•
documentation, primary limitations shall apply. Documentation shall be reported as a:
attachment to the Discharge Monitoring Report for the appropriate period.
)~ When the most sensitive analytical method which complies with Part I.G.2. of the permit h=_
a detection limit greater than or equal to the permit limit, the permittee shall repo
"less than the detectable limit," as appropriate. Such reports shall not be considered el
violations of the permit limit.
The present lowest method detection limits for specific parameters (which have limitatio+~'
which are, in some cases, less than or equal to the detection limit) are as follows:
Total Residual Chlorine
Cadmium*
Copper*
Lead*
Total Mercury
Nickel*
Silver*
Zinc*
Benzene

0.05 mg/Y
0.0003 mg/E
0.005 mg/F
0.005 mg/t
0.00025 mg/?
0.05 mg/Y
0.0002 mg/1
0.05 mg/?
0.005 mg/Y
The present lowest method detection limits for the dissolved and also potentially dissoly,
metal parameters are the same as those for the total recoverable parameters.
J The potentially dissolved metal fraction is defined in The Basic Standards and Methodologi~
for Surface Water 3.1.0 (5 CCR 1002-8) as: that portion of a constituent measured from t~
filtrate of a water and suspended sediment sample that was first treated with nitric ac's
to a pH of 2 or less and let stand for 8 to 96 hours prior to sample filtration using a (~
or 0.45-UM membrane filter. Note the "potentially dissolved" method cannot be used whe~
nitric acid will interfere with the analytical procedure used for the constituent measure