Engineers, architects, and contractors know the acronym CAD to mean computer-aided design. But there are other terms that fit CAD and not all of them are positive. In California, there is an ongoing battle between environmentalists and the local and state agencies responsible for hazardous waste removal and disposal and it revolves around another meaning for CAD.
The issue is disposal of contaminated sludge into the center of Newport Harbor, creating a potential environmental hazard for residents and visitors. Newport Beach proposes to dig what critics call “a giant hole the size of five football fields.”
The Challenge
From the 1930s until the early 1970s, multiple government agencies including the California Regional Water Quality Control Board and the USACE (U.S. Army Corps of Engineers) approved ocean disposal of domestic, industrial, and military waste at 14 deep-water locations off the coast of Southern California.
Waste disposed included: refinery wastes, filter cakes and oil drilling wastes, chemical wastes, refuse and garbage, military explosives, and radioactive wastes. Very little is known about the history of this deep-ocean disposal, the nature of the wastes, or waste sources. It was dropped into a black hole, never to be thought of again, it seems.
Normal maintenance dredging in the Main Channel and channel offshoots tends to expose some sediment that has been determined to be unsuitable for open ocean disposal (dangerous to sea life) and therefore requires an alternate disposal location. Dredging of these areas is not feasible without also identifying a practicable management option for the unsuitable sediment.
The CAD Solution
To that end, Newport Beach proposed construction of a CAD (confined aquatic disposal) facility in the central portion of Newport Harbor between Bay Island, Lido Isle, and Harbor Island where dredged sediment unsuitable for open ocean disposal or nearshore placement can be contained.
CAD in this case is defined as a large depression or a deep hole to permanently contain the unsuitable material. A hole would be dug 47-ft. below the existing harbor floor, then a dredge scow would place the unsuitable material within the hole, and a layer of clean material would be placed as a final cap. The project is estimated to take two to four years.
The Project
Newport Harbor is one of the largest recreational harbors in the United States. Natural processes result in the movement and accumulation of sediment, which must be dredged periodically to maintain channel depth for safe navigation. The Federal Channels are composed of the deeper Entrance Channel area, several sections of the Main Channel leading to the Turning Basin, and several shallower offshoots from the Main Channel. The Federal Channels are maintained by the USACE (U.S. Army Corps of Engineers).
The remainder of the harbor is managed and maintained by the City of Newport Beach and the County of Orange. To assist the USACE with dredging the Federal Channels to their authorized depth, the City and County contribute funds to maximize the dredging effort.
According to Friends of Newport Harbor, a volunteer group of residents and local supporters in Orange County, boats regularly drop heavy anchors into the sediment at the bottom of the anchorage and drag them until they are secured, then disturb the sediment again when the anchor is pulled up. Their concern, therefore, is that this natural action of boaters in the harbor will disturb the covering layer of sediment, exposing the contaminated sludge.
They point to a recent case, in Huntington Beach, where the force of anchor dragging caused a pipeline leak that spilled tens of thousands of gallons of crude oil into the ocean. Sediment is also disturbed by propeller thrust during anchoring and idling.
If disturbed, “dredged sediment unsuitable for open ocean disposal” will drift to the many popular public beaches adjacent to the anchorage and lining the harbor, from Balboa Peninsula and various islands to Corona del Mar.
For clarification, this “sediment unsuitable for open ocean disposal” has unacceptable levels of mercury and other toxins, and the “final three-foot-thick cap layer” of uncontaminated sediment is the only construction to contain this contaminated sediment.
What’s Next
Friends of Newport Harbor want the city to postpone the authorization of the project until further evaluation is made, pointing out that instead of cleaning up the contaminated material and disposing it on land, the plan is to take the highly concentrated contaminated material and dispose of it in the residential recreational harbor, pulling it out of the water and putting it back into the water.
In addition, it believes accepting the permit is premature, as there is ongoing sediment sampling that has not been completed to give an accurate determination of the amount of material that is suitable or unsuitable for ocean disposal. Unfortunately, despite being a stated benefit of the plan, the CAD proposal does not guarantee the residents the ability to dispose of their unsuitable material in the CAD.
The city counters sediment sampling in 2018 and 2019 was conducted to define the sediment characteristics so disposal options could be evaluated. This sampling effort determined that most of the material was deemed suitable for disposal at the federally permitted open ocean location or along the nearshore zone to replenish the city’s ocean beaches.
In addition to dredging the Main Channels, the Newport Beach also proposes to allow maintenance dredging in sections of Newport Harbor outside of the Federal Channels to re-establish safe navigation. This material could also be disposed within the CAD while it is still open and available.
Because the USACE requires the city, as the local sponsor, provide plans for disposing unsuitable material (i.e. CAD), the city must prepare environmental review documents, which are compliant with the CEQA (California Environmental Quality Act). The city has also developed an EIR (Environmental Impact Report).
The City of Newport Beach and the Army Corps of Engineers claim this is the right approach, the Friends of Newport Harbor want them to find another way, one with less chance of failure under normal activities in the harbor. Only time will tell how all of this will play out.
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