Any new source subject to this subpart must achieve the following new source performance standards (NSPS):

NSPS Effluent Limitations

Open Table
Stream Pollutant parameter NSPS effluent limitations
Produced Water:
(A) All coastal areas except Cook Inlet No discharge.
(B) Cook Inlet Oil & Grease The maximum for any one day shall not exceed 42 mg/l, and the 30-day average shall not exceed 29 mg/l.
Drilling Fluids, Drill Cuttings, and Dewatering Effluent:1
(A) All coastal areas except Cook Inlet No discharge.
(B) Cook Inlet:
Water-based drilling fluids, drill cuttings, and dewatering effluent SPP Toxicity Minimum 96-hour LC50. of the SPP Toxicity Test4 shall be 3% by volume.
    Free oil No discharge.2
    Diesel oil No discharge.
    Mercury 1 mg/kg dry weight maximum in the stock barite.
    Cadmium 3 mg/kg dry weight maximum in the stock barite.
Non-aqueous drilling fluids and dewatering effluent     No discharge.
Drill cuttings associated with non-aqueous drilling fluids     No discharge.5
Well Treatment, Workover and Completion Fluids:
(A) All coastal areas except Cook Inlet No discharge.
(B) Cook Inlet Oil & Grease The maximum for any one day shall not exceed 42 mg/l, and the 30-day average shall not exceed 29 mg/l.
Produced Sand No discharge.
Deck Drainage Free Oil3 No discharge.
Sanitary Waste
Sanitary M10 Residual Chlorine Minimum of 1 mg/l and maintained as close to this concentration as possible.
Sanitary M9IM Floating Solids No discharge.
Domestic Waste Floating Solids, Garbage and Foam No discharge of floating solids or garbage or foam.

1NSPS limitations for dewatering effluent are applicable prospectively. NSPS limitations in this rule are not applicable to discharges of dewatering effluent from reserve pits which as of the effective date of this rule no longer receive drilling fluids and drill cuttings. Limitations on such discharges shall be determined by the NPDES permit issuing authority.

2As determined by the static sheen test. See §435.41(ff).

3As determined by the presence of a film or sheen upon or a discoloration of the surface of the receiving water (visual sheen).

4As determined by the suspended particulate phase (SPP) toxicity test. See §435.41(ee).

5When Cook Inlet operators cannot comply with this no discharge requirement due to technical limitations (see appendix 1 of subpart D of this part), Cook Inlet operators shall meet the same stock limitations (C16-C18 internal olefin) and discharge limitations for drill cuttings associated with non-aqueous drilling fluids for operators in Offshore waters (see §435.15) in order to discharge drill cuttings associated with non-aqueous drilling fluids.

[61 FR 66125, Dec. 16, 1996; 62 FR 1682, Jan. 13, 1997, as amended at 66 FR 6918, Jan. 22, 2001; 77 FR 29846, May 18, 2012]


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