HYDRO29057

• Permit No: M1988112
• IBM Index Class Name: Hydrology
• Doc Name: TABLE OF CONTENTS
• Media Type: D
• Archive: No

COLORADO DEPARTMENT OF HEALTH, Waler Quality Control Division
Rationale -Page I S Permit No. CO-0045675
V/.B.4. Discussion o(EJjluent Litnitations (Cont.)
(d) Anddegradation Review.• (Cont.)
For the BMRI antidegradation review, conditions (i) and (iv) as described above are not applicable, since the
dilution ratio is less than 100 to 1, and this is not a shoe-term or temporary discharge. The antidegradation-
based water quality standards and (imitations jor this permit are based upon considerations of (ii) and (iii) which
are described previously.
Thus, the antidegradation-based Litnitations are calculated by either: l) the new loading is less than !S percent of
the available increment between low flow pollutant concentrations and the relevant smndards, or 2) the new
loading jor each parameter is less than 10 percent of the baseline load. In most cases, the IS `7 incremental
increase is used as the basis jor the antidegradation-based litnilatiorr. Table V/-3 following shows the
antidegradation-based and rater quality standard-based calculations.
Table V/-3 -- Summary ojMass Balance Calculations- Outfall 0016 (250 gpm dischargeJlow•)
Anridegradation-based '
Upstream Segment 28 Antidegradation- &/or WQS-Based #
Ambiem Mean Water Quality Std Based WQS E~'luenr Concentrariore
Parameter Concentration Acute/Chronic Chronic (orAcure) Acute/Chronic
(mg/I) (Ml) c/ (M3) a/ (M3} (M2}
Atnrnonia, Total as N 0.025 e/ 0.414 0.232 0.90 •
Boron, Total 0.050 e/ 0.750 0.155 0.494 *
Chloride, Total 3.0 250 42.4 /69 `
Tonal Residual Chlorine 0 b/ 0.019/0.01 / 0.0/1 0.063# / 0.011 • g/
Cyanide, Free 0.0050 e/ 0.005 (nnue) 0.005 j/ 0.005 •
Fecal Colijonn Bacteria, No. /IOO mI 0 b/ 2000 2000 g/ 2000 • g/
Fluoride, Total ~ 0.50 (4.0 = MCL) p.165) 2.7 •
Nilrate, Total as N 0.065 10 (acute) ~ 2.10 6.9 *
Nitrite, Total as N 0 d/ 0.050 0.050 g/ 0.050 * g/
Sulfate, Total 9.1 250 74 283
Sulfide as H,S 0.000025 e/ 0.002 0.00073 0.0030 •
Arsenic, Total 0.00050 e/ 0. 050 (acute) 0.0084 0.027 •
Cadmium, Potentially Dissolved 0.000050 e/ 0.00597/0.00080 0.00016 0.020# / 0.00053 •
Chromium, Trivalent, Tor. Rec. 0.00050 e/ 0.050 (acute) 0.0083 0.026 •
Cl:romiutn, Nezavaletrt, Pot. Dis. O.CQ750 e/ 0.016/0.011 0.0024 0.052# / 0.0086 *
Copper, Potentially Dissolved 0.00050 e/ 0.012/0.0081 0.0076 0.038# / 0.0053 •
Iron, Dissolved 0.0595 0.300 0.300 j/ 0.300 ` j/
Iron, Total Recoverable 0.154 I.0 1.0 j/ 1.0 j/
Lead, Potentially Dissolved 0.00050 e/ 0.047/0.0021 0.00074 0.15# / 0.0015
Manganese, Dissolved 0.0050 e/ 0.050 0.050 j/ 0.050 • j/
Manganese, Total Recoverable 0.0050 e/ !.0 0.376 1.6 *
Mercury, Taal 0.000050 e/ 0.000010 0.000010 g/ 0.000010 • g/