Exhibit D Discharge Goals.pdf
PDF 97 KB Posted
- Attached to
- Captain Jack Mill Superfund Site O & M
- Solicitation number
- RFP FAAA 2026000184 4
- Issued by
- Denver County, Denver City, Colorado
About this file
Exhibit D is a discharge goals document applicable to the Captain Jack Mill Superfund Site Operations and Maintenance contract, which is being procured by the State of Colorado on behalf of Denver County and Denver City. The document establishes effluent parameter limitations and monitoring requirements for site water discharge across two distinct seasonal periods: Low Flow Season (October through April) and High Flow Season (May through September). The discharge goals specify 30-day average, 7-day average, and daily maximum concentration limits for multiple parameters including flow rate, pH, total suspended solids, oil and grease, and trace metals (arsenic, cadmium, chromium, copper, iron, lead, manganese, nickel, selenium, silver, and zinc), as well as sulfate, sulfide, and thallium. Monitoring frequencies are predominantly monthly using grab samples, with continuous recorder requirements for effluent flow and daily pH monitoring. Whole effluent toxicity testing is required on a semi-annual basis.
The discharge limitations are substantially more stringent during the Low Flow Season compared to the High Flow Season, reflecting seasonal variations in water volume and dilution capacity. For example, the effluent flow goal is 0.046 million gallons per day during low flow versus 0.1296 million gallons per day during high flow, and metal concentration limits increase proportionally during the high flow period to account for greater water volume. These parameters establish the environmental compliance baseline for the contractor's operations and maintenance of the site's permanent and temporary water treatment systems, with performance monitoring essential to meeting applicable water quality standards and regulatory requirements under the permit governing the Superfund site remediation.
View the file
Other files
Show all 15
On GovTribe
Work with this file
- Download the original file
- Contacts named in this file
- Similar government files
- Ask GovTribe AI about this file
Text version
Low Flow Season: October – April – Discharge Goals
Effluent Parameter
Effluent Limitations Maximum Concentrations
Monitoring Requirements
30-Day Average
7-Day Average
Daily Maximum Frequency Sample Type
Effluent Flow (MGD) 0.046 Report Continuous Recorder pH (su) 6.5-9.0 Daily Grab
TSS, effluent (mg/l) 30 45 Monthly Grab
Oil and Grease (visual) NA Report Monthly Visual
Oil and Grease (mg/l) NA 10 Contingent Grab
As, TR (µg/l) 50 NA Monthly Grab
As, PD (µg/l) NA 340 Monthly Grab
Cd, PD (µg/l) 1.5 2.1 Monthly Grab
Cr, TR (µg/l) Report Report Monthly Grab
Cr+3, TR (µg/l) NA 50 Contingent Grab
Cu, PD (µg/l) 5.6 8 Monthly Grab
Fe, Dis (µg/l) 1178 NA Monthly Grab
Fe, TR (µg/l) 1000 NA Monthly Grab
Pb, PD (µg/l) 1.4 36 Monthly Grab
Mn, Dis (µg/l) 1376 2490 Monthly Grab
Ni, PD (µg/l) 33 295 Monthly Grab
Se, PD (µg/l) 4.6 18 Monthly Grab
Ag, PD (µg/l) 0.029 0.8 Monthly Grab
Zn, PD (µg/l) 74 74 Monthly Grab
Sulfate (mg/l) 318 NA Monthly Grab
Sulfide as H2S (mg/l) 0.002 NA Monthly Grab
Thallium, (Tot) (µg/l) 0.24 NA Monthly Grab
WET, Testing Semi-
Annually Grab
High Flow Season: May – September – Discharge Goals
Effluent Parameter
Effluent Limitations Maximum Concentrations
Monitoring Requirements
30-Day Average
7-Day Average
Daily Maximum Frequency Sample Type
Effluent Flow (MGD) 0.1296 Report Continuous Recorder pH (su) 6.5-9.0 Daily Grab
TSS, effluent (mg/l) 30 45 Monthly Grab
Oil and Grease (visual)
NA Report Monthly
Visual
Oil and Grease (mg/L)
NA 10
Contingent
Grab
As, TR (µg/l) 220 NA Monthly Grab
As, PD (µg/l) NA 1496 Monthly Grab
Cd, PD (µg/l) 6.6 9.2 Monthly Grab
Cr, TR (µg/l) Report Report Monthly Grab
Cr+3, TR (µg/l) NA 220 Contingent Grab
Cu, PD (µg/l) 18 28 Monthly Grab
Fe, Dis (µg/l) 4836 NA Monthly Grab
Fe, TR (µg/l) 4036 NA Monthly Grab
Pb, PD (µg/l) 6.2 158 Monthly Grab
Mn, Dis (µg/l) 6037 10939 Monthly Grab
Ni, PD (µg/l) 143 1296 Monthly Grab
Se, PD (µg/l) 20 81 Monthly Grab
Ag, PD (µg/l) 0.13 3.5 Monthly Grab
Zn, PD (µg/l) 247 247 Monthly Grab
Sulfate (mg/l) 1382 NA Monthly Grab
Sulfide as H2S (mg/l) 0.0088 NA Monthly Grab
Thallium (TR) (µg/l) 0.83 NA Monthly Grab
WET, Testing Semi-
Annually Grab
File details come from the government source that posted it. Updated .