HYDRO30633

• Permit No: M1977410
• IBM Index Class Name: Hydrology
• Doc Date: 7/9/1991
• Doc Name: RATIONALE FOR PUBLIC NOTICE
• Media Type: D
• Archive: No

~ COLORADO DEPARTMENT O~EALTH, Water Quality Control L~/ision
Permit Number CO-0032751 Page 5 .
APPLICABLE RULES AND REGULATIONS: (Continued)
B. State: (Continued)
Table 1 shows a comparison of the applicable state and federal. limitations.
Table 1 - Applicable Limitations
Parameter
BA
~~
30/45 N/A
6.0 - 9.0 6.5 - 9.0
10.0 N/A
N/A TVS
N/A TVS
N/A TVS
N/A TVS
N/A TVS
N/A N/A
for the State Discharge
Total Susp. Solids, mg/1 20/30
pH, s.u. 6.0 - 9.0
Oil and Grease, mg/1 N/A
Cadmium, mg/1 0.05/0.10
Copper, mg/1 0.15/0.30
Lead, mg/1 0.3 /0.6
Hercury, mg/1 0.001
Zinc, mg/1 0.75
WET Testing N/A
WET testing is required per Regulations
Permit System 6.1.0 (5 CCR 1002-2).
The BPT/BAT limits for the metal parameters are specified as the t:ocal value.
TVS refers to Table Value Standards, which for Cadmium, Copper, Lead, and Zinc
are determined from hardness-based equations. These TVS values ar•e expressed
as the potentially dissolved fraction for effluent limits as determined from a
mass balance equation. Tha hardness-based equations and the TVS values for
Hercury are included in the Basic Standards and Methodoloeies (Reference 1).
The calculated water quality standard values are indicated in Appendix A.
LIMITATIONS AND RATIONALE:
Table 2 below and on the following page shows theapplicable effluent
limitations, rationale for each limitation and required monitoring; frequency:
Table 2 - Permit Limitations and Monitoring Requirements
Monitoring
Parameter Limitations Rationale Frequency
Flow, MGD 0.036 JJ Mass Balance Basis Daily
0.122 J~/ Mass Balance Basis Daily
0.093 Jg/ Hass Balance Basis Daily
TSS, mg/1 20/30 ~ BPT/BAT Monthly
P.D. Cadmium, mg/1 0.0014 - 0.0042 a/ WQS Weekly
0.0048 - 0.025 J WQS Weekly
J 30 day average (limits range for metals)
30 day average/ Daily maximum e/ August through M<<rch
~/ Allowable range ~/ April through Jurie
J Daily maximum ( limits range for metals) g/ July 1 through JL~ly 31