Sector - G-3 Sector - G-3

Sector-Specific Benchmark Values and Effluent Limitations: Sector - G-3. Discharges may be subject to requirements for more than one sector or subsector.
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Discharge/Source of Discharge	Note/Comment
Piles
Waste rock/overburden	If composed entirely of stormwater and not combining with mine drainage. See note below.
Topsoil	No additional comments
Roads constructed of waste rock or spent ore
On-site haul roads	If composed entirely of stormwater and not combining with mine drainage. See note below.
Off-site haul and access roads	No additional comments
Roads not constructed of waste rock or spent ore
On-site haul roads	Except if mine drainage is used for dust control
Off-site haul and access roads	No additional comments
Ore Processing/Plant Site
Runoff from tailings dams and dikes when constructed of waste rock/tailings	Except if process fluids are present and only if composed entirely of stormwater and not combining with mine drainage. See note below.
Runoff from tailings dams/dikes when not constructed of waste rock and tailings	Except if process fluids are present
Concentration building	If stormwater only and no contact with piles
Mill site/pellet plant	If stormwater only and no contact with piles
Ancillary areas
Office and administrative building and housing	If mixed with stormwater from the industrial area
Chemical storage area	No additional comments
Docking facility	Except if excessive contact with waste product that would otherwise constitute mine drainage
Explosive storage	No additional comments
Fuel storage (oil tanks/coal piles)	No additional comments
Vehicle and equipment maintenance area/building	No additional comments
Parking areas	But coverage unnecessary if only employee and visitor-type parking
Power plant
Truck wash area	Except when excessive contact with waste product that would otherwise constitute mine drainage
Reclamation-related areas
Any disturbed area (unreclaimed)	Any disturbed area (unreclaimed)
Partially/inadequately reclaimed areas or areas not released from reclamation requirements	No additional comments

Note: Stormwater runoff from these sources is subject to the NPDES program for stormwater unless mixed with discharges subject to 40 CFR pt. 440 that are regulated by another permit prior to mixing. Non-stormwater discharges from these sources are subject to NPDES/SDS permitting and may be subject to the effluent limitation guidelines under 40 CFR pt. 440. Discharges from overburden/waste rock and overburden/waste rock-related areas are not subject to 40 CFR pt. 440 unless: (1) it drains naturally (or is intentionally diverted) to a point source; and (2) combines with “mine drainage” that is otherwise regulated under the Part 440 regulations. For such sources, coverage under this permit would be available if the discharge composed entirely of stormwater does not combine with other sources of mine drainage that are not subject to 40 CFR pt. 440, as well as meeting other eligibility criteria contained in Part I of the permit. Permit applicants bear the initial responsibility for determining the applicable technology-based standard for such discharges.