HYDRO24194

• Permit No: M1980244
• IBM Index Class Name: Hydrology
• Doc Name: AMENDMENT 1 RATIONALE CRIPPLE CREEK & VICTOR GOLD MINING CO A JOINT VENTURE BETWEEN PIKES PEAK MININ
• Media Type: D
• Archive: No

( i
COLORADO DEPARTMENT OF HE •, Water Quality Control Divisio•
Rationale - Page 2. Permit No. CO-0024562.
III. RECEIVING STREAM:
A. Identification, Classification and Standards
1. Identification: Discharge is to Fourmile Creek, tributary to the
Arkansas River, segment 21 of the Upper Arkansas River Basin.
2. Classification: This stream segment is classified for the
following uses: Recreation, Class 2; Aquatic Life, Class 1 (Cold);
Agriculture.
3. Numeric Standards: Standards for the following metals are based
upon equations found in Table III of 3.1.0 "The Basic Standards and
Methodologies for Surface Water". The calculated standards and
their corresponding assumptions can be found in Part VI.B of this
rationale.
Cadmium Lead
Trivalent Chromium Nickel
Hexavalent Chromium Silver
Copper Zinc
The remaining standards which are impacted by this discharge are:
Physical and Biological
D.O. = 6.0 mg/1, 7.0 mg/1 spawning
pH = 6.5 - 9.0 s.u.
Fecal Coliforms = 2000/100 ml,
Inorganic
Unionized Ammonia
Residual Chlorine
Cyanide (free)
Sulfide as H2S
Boron (B)
Nitrite (N02)
Metals
(NH3) = 0.02 mg/1
(C12) = 0.003 mg/1
= 0.005 mg/1
= 0.002 mg/1 undis
= 0.75 mg/1
= 0.05 mg/1
Arsenic (As) = 0.05 mg/1
Iro^ (Fe, tot. rec) = 1.0 mg/1
Manganese (sol) = 1.0 ~g/1
Mercury (Hg, tot. rec)= 0.01 mg/1
Selenium (Se) = 0.017 mg/1