The following incidents in CIRCAC’s area of responsibility and concern have warranted monitoring and/or advice, recommendations, data, and expertise. This page contains the information released through the Unified Command as well as descriptions of the most recent incidents in our areas of responsibility and concern.

Note: Click here to see documented Drills and Exercises.


January 20 -Through routine contact with industry representatives, staff received a report from the BlueCrest Energy, Regulatory Permitting & Compliance Coordinator, of a 40-gallon glycol spill that occurred on Thursday.

The spilled fluid was a 50/50 solution of glycol and water and an undetermined amount of Natural Gas Liquids (NGLs). The glycol solution is used to cool natural gas before it is shipped to the Enstar pipeline. The cooling also allows NGLs to drop out before shipping. The mixture sprayed as a mist onto the ground through a vent associated with a pump. The pump had been shut down but was being periodically started to keep warm along with other equipment.  When the pump and other equipment were restarted, a slug of NGLs went to a boiler, causing them to quickly evaporate which built up pressure, resulting in a spill through the vent.  The vent worked as designed, by preventing a dangerous pressure overload, but also allowed the fluid to be sprayed out. The sprayed mist was contained on the pad, no personnel were injured, and no materials entered Cook Inlet. Facility personnel are removing all contaminated snow/soil to be properly disposed of. BlueCrest Energy is in communication with the manufacturer to determine how to prevent this from recurring. Staff will continue to monitor and report on Cook Inlet operations.


October 3 -Staff has maintained contact with the ADEC and the USCG concerning ongoing response and repairs at the Offshore Systems Kenai (OSK) facility. Staff confirmed that the U.S. Coast Guard (USCG) had issued verbal orders on October 2nd and followed up with written orders on October 3rd to the Responsible Party (RP) to evacuate the remaining oil from the second fuel transfer station pipeline and to remove other hazardous materials from the dock area. That order has been carried out and no fuel or hazardous material remains on the dock area. The USCG has also issued a written order to the facility, prohibiting oil or hazardous materials operations until engineers certify repairs as safe for work to be performed or the USCG approves an operational plan for dock operations to resume. While USCG personnel were on scene conducting their investigation and final assessment of the pollution threat, another approximate 15 feet of dock face collapsed.  ADEC reports that OSK has hired engineers to assess the stability of the dock for repair or continued operations.

The OSK dock is a component of the Cook Inlet Spill Prevention and Response Inc. (CISPRI) response operations as a launch and departure facility for vessels and personnel.  Staff contacted CISPRI regarding the impact this collapse will have on their response capability. CISPRI personnel explained that their large floating assets are already on the water and their smaller vessels can be launched from either the Kenai River or the boat launch at OSK, which remains unaffected at this time. ADEC is coordinating with CISPRI to mitigate impacts to response preparedness related to use of the OSK dock.

ADEC personnel surveyed the area north on the beach about a half mile and south on the beach about 300 feet.  They reported no sheen or diesel odor in either direction.  Based on their observations today and yesterday, they are not recommending beach cleanup tactics or placement of warning signs on the beach for recreational users.


News Release


U.S. Coast Guard 17th District Alaska
Contact: 17th District Public Affairs
Office: (907) 428-4181
After Hours: (907) 209-6509
17th District online newsroom

Coast Guard closes portion of Offshore Systems Kenai dock in Nikiski, Alaska

ANCHORAGE, Alaska — The Coast Guard Captain of the Port closes portion of Offshore Systems Kenai (OSK) dock in Nikiski, Alaska, Wednesday.

All operations on the north face of the pier are suspended until permanent repairs can be made following a partial dock collapse and subsequent discharge of approximately 300 gallons of diesel fuel.

Coast Guard pollution responders from Marine Safety Detachment Homer responded to a report that heavy seas caused a 50-foot wide section of the dock to fall into Cook Inlet. Pollution responders are working with the responsible party and state authorities to mitigate further pollution. The dock continues to erode, but all remaining oil and hazardous materials have been removed.

“The Coast Guard is temporarily closing the north portion of the dock as a precaution to protect life and property as well as reduce further impact to the environment,” said Capt. Sean MacKenzie, Coast Guard Captain of the Port, Western Alaska.

Members of the public who find oil or other signs of pollution in the area are asked to report it to the National Response Center at 1-800-424-8802.









April 27 – Coast Guard, contractors respond to pollution threat from derelict barge on Kodiak Island, Alaska

A light, rainbow-colored sheen was observed coming from the vicinity of this derelict barge on the southeast shoreline of Womens Bay on Kodiak Island, Alaska, April 25, 2019. Coast Guard pollution investigators from Marine Safety Detachment Kodiak are working with contractors to mitigate the pollution threat. U.S. Coast Guard photo by MSD Kodiak

KODIAK, Alaska—The Coast Guard is working with contractors Saturday to mitigate the potential pollution threat posed by a derelict barge on the shoreline of Womens Bay on Kodiak Island.

The Coast Guard verified an approximate 300-yard long, 1-yard wide, patchy, rainbow-colored sheen coming from the vicinity of the barge that has been grounded on shoreline of the southeast corner of Womens Bay for several years. The Coast Guard opened the Oil Spill Liability Trust Fund for $150,000, and hired Global Diving and Salvage to assess the situation and help mitigate the pollution threat.

Containment boom has been placed around the barge. Contractors plan to begin pumping product from the barge Saturday afternoon.

Coast Guard pollution investigators from Marine Safety Detachment Kodiak initially responded to a report Thursday morning of a rainbow-colored sheen coming from the vicinity of the barge.

The maximum potential for fuel and or oily waste that remain on the barge and the barge’s owner are still unknown.

“Our job is to ensure the potential for pollution in this situation is mitigated,” said Coast Guard Chief Petty Officer Emily Clore, Federal On Scene Coordinator Representative for the case. “The sheening so far is relatively light, and seems to be discharging intermittently, at a slow rate. But protecting the pristine maritime environment surrounding Kodiak Island is our top priority here.”


CIRCAC Staff contacted Marine Safety Detachment (MSD) Kodiak for further details. This barge was converted to a fish processor at some time in the past and is not a tank barge. The barge had approximately 1000 gallons of accumulated fluids in some of the void spaces. The origin and identification of the contaminated fluids on the barge are unknown at this time. Approximately 800 gallons of fluids (a portion is suspected to be accumulated rain water) have been removed. Along with the boom mentioned in the press release, responders have deployed a beach deluge system to the affected beach area to prevent contaminants from settling and to flush any contaminants from the area and make them available for recovery.



CIRCAC Staff received information on June 5, 2018, about a crude oil discharge that occurred during work on the Hilcorp owned Middle Ground Shoal (MGS) subsea pipeline. The release was in the vicinity of Platform A as divers were working on the Platform-A subsea pipeline reconfiguration project. They were disconnecting a flange on a confirmed closed valve line. At approximately 11:00, topside crew on the platform noticed approximately 10 to 15 (up-to 1 inch in size) tar balls floating on the surface near the platform. The flange was secured with a blind flange. Hilcorp had CISPRI response assets standing by with its skimmers deployed throughout the operation as part of their response protocols for the operation. CISPRI responders recovered the tar balls and any recoverable sheen. Estimated recovered crude oil (tar balls and sheen) was approximately 1 cup. Hilcorp notified all appropriate agencies.

Prior to the project start, Hilcorp had submitted to the Alaska Department of Environmental Conservation (ADEC) their “2018 MGS Pipeline Removal and Replacement Spill Mitigation Plan.” As part of that plan Hilcorp implemented the following spill prevention/mitigation measures for the work scheduled.

  • An open-cell sponge and temporary blind flange equipped with a neoprene gasket will be installed at pipeline breaks to contain and seal the pipelines.
  • Oil spill response equipment including a Cook Inlet Spill Prevention & Response, Inc. (CISPRI) vessel will be on stand-by one hour before, during, and one hour after pipeline disconnection activities.
  • Over-flights will be conducted over the project area during slack tide to monitor for a sheen each day that pipelines are non-continuous (while any portion of the sub-sea pipeline is not continuously connected at flanges or valves). Results of daily overflights will be recorded.
  • Platform personnel on Platform A and Platform C will visually inspect the area during slack tide to monitor for a sheen each day that pipelines are non-continuous. Results of daily visual inspections will be recorded.


Platform Anna

The cause of this incident, and quantity of release, are under investigation.

Note: Throughout this incident, CIRCAC participated in the Unified Command to monitor the response and provide advice, recommendations and resources.

April 3, 2017


Nikiski, Alaska – The Unified Command comprised of the United States Coast Guard (USCG), Alaska Department of Environmental Conservation (ADEC), and Hilcorp Alaska (Hilcorp) responding to a reported sheen in Cook Inlet stood down this morning at 9am after a final overflight this morning confirmed no sheening.

Hilcorp crews successfully and safely evacuated all crude oil from the suspected leaking pipeline by displacing it with filtered seawater.  The pipeline is an oil gathering line connecting the Anna and Bruce platforms. Cook Inlet Spill Prevention and Response (CISPRI) remained on scene and USCG and ADEC Observers were on board the Anna platform for the purging operation.

Overflights were conducted at 700pm Sunday evening and at 750am this morning. No sheen was observed. The Perseverance, a CISPRI vessel, remained on standby through the evening and will do a final survey of area later today.

A diving crew is assembling in the region accompanied by the appropriate support vessels.  Use of divers to investigate and perform any necessary repairs will be initiated as soon as it is safe to do so.

At this time, the exact cause of the release is unknown and remains under investigation.


Media can reach the Unified Command Information office by contacting:
Lori Nelson   Candice Bressler   Coast Guard Public Affairs  907-777-8392   907-465-5009    907-209-8731



Nikiski, Alaska – A Unified Command comprised of the United States Coast Guard (USCG), Alaska Department of Environmental Conservation (ADEC), and Hilcorp Alaska (Hilcorp) has been established in response to reports of a sheen near the Anna Platform.

The Anna Platform is located in the Granite Point Field of Cook Inlet. A sheen was discovered by Hilcorp personnel at 11:20am on Saturday, April 1. Production was shut in immediately and the incident was reported to ADEC at 12:05pm on the same day.

Three flyovers were conducted yesterday. During the first flyover at approximately 11:30am, several sheens were spotted approximately 3 miles downstream from the platform. The other two flights did not identify any sheen in the area. Two additional flyovers were completed today at 10:45am and 2pm. No sheen was sighted in the area.

The suspected source of the release is an oil pipeline running between the Anna and Bruce platforms. In order to reduce the risk of a further spill, platform crews are displacing the existing oil in the pipeline with seawater. USCG and ADEC personnel have boarded the Anna platform and will be observing the operation. The Perseverance, a Cook Inlet Spill Prevention and Response (CISPRI) vessel, is also on scene and will remain there until the oil is removed from the line.

At this time, the cause of the release and sheen is unknown. Further updates will be provided when they become available.


Media can reach the Unified Command Information office by contacting:

Lori Nelson


Candice Bressler


Coast Guard Public Affairs


Platform A Gas Pipeline Leak (Hilcorp)

CIRCAC’s congressional mandates specify our role in crude oil transportation and facility operations. Though natural gas supply lines do not specifically fall within those mandates, we are concerned any time a hazardous substance is introduced into the Inlet. We’re providing our data and expertise in any way that can improve decisions being made about this incident, which is a reminder of Cook Inlet’s aging infrastructure, specifically subsea pipeline integrity.

CIRCAC’s Director of Science and Research, Susan Saupe, has been contacted as a subject matter expert about parts of the monitoring plan based on her experience sampling in Cook Inlet, including in the high current scenarios north of the Forelands.  She has provided her recommendations to the state and resource agencies.  As we understand, the State’s final recommendations to Hilcorp are still being considered.  We’re also providing access to the ice camera network to assist.


Drift River Oil Terminal Spill

In July, Hilcorp Alaska reported a crude oil discharge associated with the piping system at the Drift River Oil Terminal tank farm. During investigation, a valve misalignment was discovered and the pump shut down. The investigation uncovered four different sites where oil contamination levels required excavation, ground water recovery and site remediation. The response continued until weather forced the suspension of operations and will be resumed this spring.

Beaver Creek

In July, Hilcorp reported a small leak from a buried crude oil line at the facility. The Beaver Creek Production Facility is located near Kenai in the Kenai National Wildlife Refuge. The leaking line had been isolated and approximately 25 gallons were spilled, 850 cubic yards of solids removed, five groundwater monitoring wells installed and over 30 confirmation samples collected. The case was transferred to ADEC’s Contaminated Sites Program for cleanup monitoring and evaluation due to its possible impacts to groundwater.

Nikiski KPL Dock
In December, a pipe ruptured at the KPL facility Tank 2400 waste water tank. The resulting discharge did not impact Cook Inlet nor were there any injuries. The ruptured pipe was isolated and contractors have been cleaning up the discharge. The Alaska Department of Environmental Conservation responded to the incident and investigated. The rupture was likely caused by freezing water in the pipe combined with pressure when put into service; 12.5 barrels of water and .6 barrels of hydrocarbons were recovered.