Bay News News

Dynegy to Remove Undersea Oil Pipes

The continued dismantling of the Morro Bay Power Plant is ready to take another major step, as plant owners Dynegy seek to decommission and remove the plant’s marine terminal undersea oil loading pipelines.

The California State Lands Commission (CSLC) is circulating an environmental document that proposes to issue a “negative-declaration” or “Neg-Dec,” under the California Environmental Quality Act or CEQA, for the decommissioning work. Deadline to comment on the 225-page document is Feb. 9 and the SLC plans to vote on the Neg-Dec at its Feb. 27 meeting, place and time TBA.

According to the Neg-Dec, “The Project would
authorize Dynegy Morro Bay, LLC to decommission the pipelines
and associated features of the MBPP Marine Terminal. Use of the State tidelands for the
marine terminal’s offshore tanker berth component is currently authorized under the
existing CSLC Lease.”

It may still be part of the plant’s lease with the State but those pipes, which run underground from the plant, under the sand dunes and the beach and offshore thousands of feet haven’t been used in decades.

The marine terminal was in operation offloading tankers with various fuels — diesel, fuel oil and even the occasional kerosene load — from 1954 until 1990, when it received its last load of fuel oil, according to the CSLC’s document.

The Commission and U.S. Coast Guard officially changed the marine terminal’s two pipelines status to “caretaker” in May and August 1997.

The pipelines’ disuse corresponded with the plant’s switching over to natural gas full time in 1997.

Built by PG&E in the 1950s and early ‘60s, the plant was sold to Duke Energy North America (DENA) in 1999. Duke had sought a permit to replace the outdated plant with a modern, energy efficient combined cycle plant.

Duke spent about 6 years and an estimated $35 million but never did get a permit to replace the plant, finally stumbling over the use of seawater for cooling steam.

DENA, a subsidiary of energy giant, Duke Energy based in Charlotte, N.C., sold its California assets in the mid-2000s to LS Power, which merged with Dynegy shortly thereafter. Houston, Texas-based Dynegy ran the plant sporadically for several years but shut it down permanently in 2014.

Since then Dynegy has done several projects to remove equipment, including a major removal of a metal exhaust manifold that was attached to the northern most, 450-foot tall smokestack.

Dynegy spokesman, David Byford, explained that for the past several months, a boat working offshore has been running a “pig,” or a device that is pushed through oil pipelines to clean them out through a process called “pigging.” Pigging cleans out residual oils and contaminants, and inspects the condition of pipelines.

With much of the marine terminal’s equipment already gone the two underground pipelines — a 24-inch and 16” diameter pipes — are left to be dealt with and Dynegy’s plans would remove parts of the pipes but leave others in place.

“The CSLC prepared an MND because it determined that, while the IS identified potentially
significant impacts related to the Project,” the Neg-Dec said, “measures have been incorporated into the
Project proposal and agreed to by Dynegy that avoid or mitigate those impacts to a point
where no significant impacts would occur.”

The decommissioning project has five facilities including the two pipelines remaining that Dynegy is proposing to decommission or abandon in place “in part or in whole.”

There are four main segments of the pipes being addressed:

• Sand Dunes: The two pipelines underneath the Sand Dunes run for approximately 1,130 feet (16-inch line) and 1,180 feet (24” line). They are buried from 2-1/2 feet to up to 18-feet below the sand. Also, two decommissioned and buried “anode beds” are located near the western edge of this segment. Anode beds are devices that use electricity to prevent corrosion in pipelines.

This sand dune segment is an “environmentally sensitive area and a City of Morro Bay restoration site,” according to the CSLC’s document.

Dynegy proposes to abandon the two pipelines in place through the Sand Dunes filling the pipes with oilfield cement or equivalent to approximately 50-feet west of the point where the dunes meet the beach, prior to being abandoned.

Dynegy also proposes to abandon in place two anode wells “and their single conductor electrical cable that traverses the sand dunes.”

• Beach Segment — The two pipelines run underneath Morro Strand Beach, and the mouth of Morro Creek. “The Beach Segment is an active recreational area and is approximately 810-feet in width from the toe of the sand dune to the point where the pipelines cross the approximate low tide line in the intertidal zone.”

Dynegy proposes to dig up and remove both pipelines from under the beach starting at the toe of the dunes out to the tide line.

• Surf Zone — The two pipelines pass underneath the surf zone from the low tide line to approximately 17-foot water depth (the approximate boundary of the surf zone), a distance of about 1,300 feet (16” line) and 1,240 feet (24”).

Dynegy proposes to attempt the removal of the two pipelines using “dynamic pipe ramming” or DPR, which “uses a pneumatically powered ram to drive or pull pipes through soil.”

• Offshore — The two pipelines continue offshore, on a heading of about 303 degrees true north, approximately 2,400 feet (16”) and 2,500 feet (24”) from the seaward side of the Surf Zone Segment to the offshore marine terminal tanker berth, at a water depth of some 54 feet.

The facilities in the “Offshore Segment,” include the two pipelines, and “helical screw anchors” that anchor the pipelines to the seafloor. There may also be small “concrete clump anchors” left over from marker buoys, and “possibly miscellaneous debris on the seafloor.”

“Dynegy proposes to excavate, expose, and remove the two offshore pipeline segments in their entirety,” CSLC’s document reads. “Removal would start at the offshore termination and work shoreward removing all pipe up to the starting point of the Surf Zone Segment.’ They plan to do this removal before the Surf Zone work.

All told, the 24” and 16” lines measure approximately 5,740 feet and 5,700 feet overall, respectively.

The plant’s original marine terminal also included several large oil storage tanks both on site of the power plant and on a hillside high above Hwy 41 east of town, as well as the offshore tanker berthing facility.

The tanker facility was removed long ago, so too the oil tank farm at the plant and off Hwy 41.

The anchorage could handle 50,000 deadweight ton tanker ships that were a regular sight in the Estero Bay for decades.

A hardcopy of the CSLC’s Neg-Dec has been placed on file at the Morro Bay Library, according to the Commission’s notice. The Bay News will post a pdf format file of the Neg-Dec document in electronic form with this story online at:

The deadline to comment is Feb. 9 and the SCLC is asking that you write: “Morro Bay Power Plant Marine Terminal Decommissioning Project Comments” in the email subject line. Email comments to:

Or mail a hardcopy of your comments to: California State Lands Commission, Attn: Jason Ramos, 100 Howe Ave, Ste. 100-South, Sacramento, CA 95825

And as for what’s being done with regards to the entirety of the power plant, company spokesman Byford said the company continues looking into options but no decisions have been made. Dynegy has long been trying to sell the Morro Bay Power Plant, as well its other California plants in Moss Landing and Pittsburgh.

The Morro Bay plant includes the 117-acre plant site, including the 16-story plant building, the trio of 450-foot smokestacks, and the large “intake building” that fronts the bay across from the plant’s front gate.

see the report: Dynegy MBPP oil pipes EIR-MND

By Neil Farrell

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