Los Angeles Basin Contaminated Sediments Task Force

Summary of Upland Disposal and Beneficial Reuse Committee Meeting

on June 13, 2000

bar4.gif (2919 bytes)

 

Attendees

Michael Lyons, LARWQCB
Rick Cameron, Port of Long Beach
Seth Molinari, URS
Mitzy Taggart, Heal the Bay
Chimin Chan, Moffatt and Nichol Engineers
Lisa Kay, MEC
Earl Byron, CH2M-Hill

Data Gaps Studies

The Upland Subcommittee members were charged with determining how to best spend their share ($150,000) of the funds that the Contaminated Sediments Task Force expects to receive in the 2000-01 state budget to conduct data gaps studies. The Subcommittee members began by reviewing the initial proposals in the finance letter, which targeted $25,000 to determine whether concrete stabilization adequately binds chlorides and petroleum hydrocarbons, $25,000 to determine whether the dewatering flow produced during physical separation would require additional treatment prior to discharge, and $100,000 to conduct a pilot project to test the suitability of fine-grained contaminated sediments (e.g., Los River Estuary dredged material) for use with the physical separation process.

Based on the beneficial re-use report produced by Harding-Lawson for the Port of Long Beach, the Subcommittee members agreed that we should focus our efforts on the most promising and most cost-effective re-use technologies. In addition to cost, one of the major impediments to re-use appears to be the lack of a market for the final product, partly due to potential public concern about recycling contaminated sediments and liability issues connected to possible release of contaminants or exposure to them.

The Subcommittee members agreed that we need to conduct a local study or survey to assess the local market for re-use of products derived from contaminated dredged material. Such a study probably could be completed within a few months and fairly inexpensively, although we cannot project the actual cost until we solicit actual proposals.

Chimin Chan provided an update on the work that Moffatt and Nichols is performing for the U.S. Army Corps of Engineers. They were tasked with outlining 4 pilot projects for disposal contaminated sediments, from which the Corps hoped to choose 3 for implementation with funds to be acquired in the next fiscal year. So far, Moffatt and Nichols has identified only three likely pilot projects (although they are trying to come up with a fourth), and they are nearing completion on the conceptual design for these: 1) capping of sediments in the borrow pit, 2) concrete stabilization, 3) blending of contaminated and clean material for constructed fill. Physical separation with fine-grained sediments was rejected, because the large volume of remaining contaminated material (90-95%) still would require additional treatment, making this too expensive. Soil washing also was rejected, since another treatment process would be needed to eliminate most of the contaminants.

The Upland Subcommittee members selected concrete stabilization as a promising re-use technique. One of the impediments (although not the only one) to implementation of this technique as an acceptable disposal alternative is uncertainty regarding the binding of all contaminants, particularly chlorides and petroleum hydrocarbons. Although treatability tests conducted by ECDC showed that these contaminants were bound with the particular sediment tested, uncertainties remain.

The Subcommittee members recommend conducting a pilot project to test different sediments (e.g., Marina del Rey, Port of Los Angeles, Port of Long Beach, Los Angeles River) to verify whether the concrete stabilization process works with all types of sediments to adequately bind or isolate all contaminants of concern from subsequent release to the environment. This will help us to determine whether the final product derived from the concrete stabilization process could be employed for unrestricted use. This pilot project should be completed within a few months and should be initiated as soon as possible; the cost cannot be reliably predicted until we issue an RFP and view actual proposals.

Later, we can determine the need for a specific pilot project. The Subcommittee members expressed a great deal of interest in conducting a pilot project (perhaps with 1000-2500 cubic yards of contaminated sediments) to test the concrete stabilization process with a mobile system (e.g., barge), which seems more practical than a permanent land-based facility. We would hope to partner with the U.S. Army Corps of Engineers to conduct such a study. The Subcommittee also will investigate the possibility of using funds from the Alameda Corridor Transporation Authority’s offset project and Equilon’s Supplemental Environmental Project to help fund such a pilot project, if necessary, possibly as part of a local sponsor contribution to the Corps’ project.

Next Meeting: Tuesday, July 25th, 1 to 3 pm, Los Angeles Regional Board office.


bluebull.gif (1028 bytes) Return to the Contaminated Sediments Task Force Committee Meetings page.

bluebull.gif (1028 bytes) Return to the Contaminated Sediments Task Force home page.

bluebull.gif (1028 bytes) Return to the California Coastal Commission's home page.