This report summarizes a survey of healthy native stocks of anadromous salmonids in the Pacific Northwest and California. We used a questionnaire approach combined with spatial analysis to describe the status and distribution of stocks considered to be in relatively good condition. These stocks now constitute a small fraction of the region's historic anadromous salmonid resource but are critical to maintaining current resource productivity. Several agencies have developed, or are in the process of developing, computerized databases that will help organize predominantly quantitative data on native stocks of anadromous salmonids. Our survey supplements those efforts by summarizing some of the knowledge of biologists familiar with the stocks and by making status assessments that at times go beyond conservative analyses of quantitative data. The survey identified 99 healthy native wild stocks of salmon and steelhead that biologists consider to be at least one‐third as abundant as would be expected without human impacts, including 20 considered at least two‐thirds as abundant. More than three‐quarters of these stocks are fall chinook, chum salmon, or winter steelhead in Puget Sound or coastal watersheds of Oregon or Washington. Fewer healthy populations remain of summer steelhead and coho, pink, and sockeye salmon and spring or summer chinook. We suggest that healthy stocks provide unique opportunities for conservation and research that are at least as important to the future of the region's anadromous salmonids as those associated with at‐risk stocks.

Sequestration of trivalent actinides and lanthanides present in used nuclear fuel and legacy wastes is necessary for appropriate long-term stewardship of these metals, particularly to prevent their release into the environment. Organically modified mesoporous silica is an efficient material for recovery and potential subsequent separation of actinides and lanthanides because of its high surface area, tunable ligand selection, and chemically robust substrate. We have synthesized the first novel hybrid material composed of SBA-15 type mesoporous silica functionalized with diglycolamide ligands (DGA-SBA). Because of the high surface area substrate, the DGA-SBA was found to have the highest Eu capacity reported so far in the literature of all DGA solid-phase extractants. The sorption behavior of europium and americium on DGA-SBA in nitric and hydrochloric acid media was tested in batch contact experiments. DGA-SBA was found to have high sorption of Am and Eu in pH 1, 1 M, and 3 M nitric and hydrochloric acid concentrations, which makes it promising for sequestration of these metals from used nuclear fuel or legacy waste. The kinetics of Eu sorption were found to be two times slower than that for Am in 1 M HNO3. Additionally, the short-term susceptibility of DGA-SBA to degradation in the presence of acid was probed using (29)Si and (13)C solid-state NMR spectroscopy. The material was found to be relatively stable under these conditions, with the ligand remaining intact after 24 h of contact with 1 M HNO3, an important consideration in use of the DGA-SBA as an extractant from acidic media.

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