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CIE, Hilcorp apply for APDES permits
Cook Inlet Energy changing how produced water handled at Osprey Platform; Hilcorp applying for Spartan 151 work at Granite Point Kristen Nelson Petroleum News
The Alaska Department of Environmental Conservation has public notices out for two Alaska Pollutant Discharge Elimination System proposed permits, one for Cook Inlet Energy and the other for Hilcorp Alaska.
Both are for facilities in Cook Inlet.
The Cook Inlet Energy APDES is for the Osprey platform, which CIE uses to produce the Redoubt field. The Hilcorp APDES is for work the Spartan 151 jack-up rig will do at the Granite Point platform, work which will be completed this year (see story in May 26 issue of Petroleum News).
Osprey platform The Osprey permit is a reissuance of an existing permit and includes additional discharges from the platform. DEC said the permit includes discharges of deck drainage, graywater and various miscellaneous discharges. It also includes, for the first time, discharge of produced water by the facility and new discharges of drill cuttings and drilling fluids at the seafloor.
DEC said it has tentatively determined to reissue a discharge permit to CIE, a subsidiary of Glacier Oil & Gas Corp.
A 2002 permit, reissued in 2009 (and administratively extended by DEC), included one mixing zone and authorized the discharge of seven waste streams.
DEC said, “many of the discharges historically have not been discharged from the Osprey Platform because UIC (underground injection control) well disposal options were available.” The discharges were authorized “should injection become infeasible or unavailable,” the agency said.
Currently Osprey is authorized to discharge deck drainage, domestic wastewater (treated black water and graywater), and several miscellaneous wastes. The platform has four underground injection control wells that allow for disposal. DEC said, “drilling fluid and drill cuttings, produced water, and many of the miscellaneous discharges have not historically been discharged from the Osprey Platform.”
The current application requests authorization to discharge produced water because it is not feasible to continue injecting produced water into the formation at the Osprey, DEC said, with produced water at the platform now coming from the West McArthur River unit as well as from the Redoubt unit. That change occurred because CIE moved the processing of West McArthur River crude to the onshore facility at Kustatan which processes Redoubt Shoal crude (see story in Oct. 16, 2016, issue of Petroleum News, as well as the coverage of Glacier in Petroleum News’ 2017 issue of The Producers).
Potable water DEC said potable water has been delivered to Osprey by vessel, although a desalination system is included in the existing system. CIE has, however, recently installed a desalination system on the platform designed to provide potable water for the minimum population of the platform - potable water delivery would still be required during peak operations, but use of the desalination system would produce discharge.
Wastewater at the platform is separated into two streams, separately treated and disposed of separately. Graywater is water from kitchens, clothes washing, lavatory sinks and showers, while black water comes from toilets and urinals.
Black water is disposed of by injection while graywater is discharged under the permit.
It is possible to treat black water to meet discharge requirements, but DEC said CIE has decided not to include discharge of treated black water in the permit, but to continue to inject it and - “if the ability to inject is not available, CIE will haul the treated black water to shore for disposal by other means.”
Injection Produced water from Osprey (the Redoubt unit) and onshore wells in the West McArthur River unit “are injected at the Osprey Platform, either for reuse as waterflood for enhanced oil recovery or for disposal as industrial waste.”
DEC said that as production at the fields matures, the produced water volume increases, and when that volume exceeds reuse and reinjection needs, alternative disposal is required.
CIE is currently disposing of 7,500 barrels per day into four injection wells at the Osprey platform. DEC said that volume represents maximum capacity, “and the receiving shallow formation has become over-pressurized,” which means it is not practical to drill additional injection wells due to safety considerations “related to well control if additional disposal wells were to be drilled into the currently over-pressurized shallow formation.”
DEC also said that increasing injection into the deeper oil-producing formations would reduce enhanced oil recovery efficiency, making the discharge of produced water necessary “to continue or expand oil production, which has economic and social benefits in the vicinity of the discharge.”
Spartan 151 jack-up Hilcorp’s proposed permit is for discharges from the Spartan 151 jack-up, which will be doing production drilling at the Granite Point platform.
DEC said that since the Spartan 151, or a similar jack-up, will be cantilevered over the existing production platform, associated discharges are considered to be from the Granite Point platform, with two discharges, noncontact cooling water and uncontaminated ballast water, not authorized for the GPP. Discharge of graywater from the GPP is authorized, but DEC said that since the Spartan 151 will discharge graywater from a separate treatment unit, it requires a separate permit.
This drilling at Granite Point is expected to be completed in the 2019 drilling season, DEC said.
While graywater will be discharged, black water from the Spartan 151 will be containerized and transported to an appropriate onshore facility for treatment and disposal.
Graywater will be treated on the Spartan 151 using marine sanitation devices and DEC said treatment of graywater using the MSDs on the Spartan 151 “has been demonstrated to exceed primary treatment requirements, and the operator has successfully obtained a waiver to secondary treatment standards from DEC,” making discharge of the treated graywater eligible for inclusion under the permit.
Noncontact cooling water is seawater used for once-through cooling of the jack-up’s drawwork breaks through a heat exchanger and is then discharged overboard. The other discharge is uncontaminated ballast water, seawater taken into a vessel hull to maintain the proper floater level and ship draft for stabilization in deeper waters, or for setting the jack-up’s legs.
DEC said that legacy vessels often combined ballast water with other vessel wastewater, “but this is not the case in newer vessels, such as the Spartan 151,” were ballast water is seawater taken into a vessel hull that is not commingled with bilge or other wastes.
As with the CIE permit, DEC said it has tentatively determined to issue the discharge permit to Hilcorp.
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