Metal concentrations, foraging distances, and fledging success of great blue herons nesting along the Hanford Reach of the Columbia River.

An ecological risk assessment of the spatial distribution of metal concentrations along the Hanford Reach of the free-flowing Columbia River in southcentral Washington, identified great blue herons, Ardea herodias, at potential risk through the ingestion of contaminated riverine biota, especially fish. We measured metal concentrations in livers of pre-flight herons from the Hanford Reach and excrement samples taken from the same nests. Nests were distributed among three colonies situated upstream and downstream from nine retired plutonium production reactors along the river where metals in reactor coolant waters had been released directly into the river or disposed to shoreline retention basins and ditches. Distances traveled by parent herons to foraging areas along the river shore were determined by visually tracking parent birds as they flew from nests to upriver and downriver foraging sites. Foraging flight distances varied between colonies with mean distances ranging between 0.7 and 3.1 km. Cadmium, Cr, and Pb concentrations were higher in excrement than in the livers of pre-flight herons but the opposite was noted for Cu, Hg, and Zn. Highest metal concentrations of Cr, Cu, Zn, Cd, and Pb, were measured in excrement taken from heron nests at the colony located upstream from all reactors. These results were consistent with metal concentrations reported in river sediment from the same regions, indicating excrement from the heron nests may be a useful indicator of dietary uptake of metals by herons. Fledging success and eggshell thickness measurements were used as an index of health of the local heron population. The results indicate that the reproductive health of great blue herons nesting along the Hanford Reach is among the highest reported in the continental United States.

Detection of metal contamination in wild asparagus near a waste disposal site.

Estimating contaminant distributions in environmental media is necesary to evaluate human and ecological hazards. Because of uncertainties in release histories and transport, traditional sampling and statistical techniques applicable to the experimental sciences may not be suitable for exploratory studies at hazardous waste sites. An approach that relies on cluster analysis of principal components (PCA) was used to identify contaminated wild asparagus (Asparagus officinalis) growing in the vicinity of waste disposal sites along the Columbia River at the U.S. Department of Energy's Hanford Site in southeast Washington state. Metals in soil samples taken from the sites contained elevated levels of Ag, Al, Ba, Cd, Cr, Cu, Hg, Ni, Pb, Sb, Zn, and V. Samples of asparagus tissue were collected from the river near the waste site, from Hanford old fields abandoned 52 years ago, and from commercial fields in the neighboring communities. Dried tissues were analyzed for metals content by ICP-mass spectrometry, furnace AA, and cold vapor AA. Tissue concentrations of elements varied over 5 orders of magnitude, from K at 46 900 ppm to As and Ag at maximum concentrations below 1 ppm. PCA produced four components that accounted for 66.2% of the metals variance. Subsequent cluster analysis using Ward's minimum variance separated the data into Columbia River and old-field groups, with the River group further divided into three clusters: plants primarily upriver from the waste sites, plants primarily downriver, and plants growing in or near the waste sites. The clustering showed that the more soluble components of the discharges (Ba and Ca) showed a pattern of distribution in the asparagus plants consistent with the ground water flow pattern, in that these elements were found far downriver of the disposal sites themselves. In contrast, the less mobile elements Al, Cd, Cr, Fe, Mn, Tl, and Zn were elevated only near the most-recently used waste disposal area. Asparagus from agricultural fields, including fields abandoned 50 years ago, contained higher concentrations of Fe, Cu, Pb, K, and Ni than did the wild riverine plants.

Strontium-90 in Canada goose eggshells and reed canary grass from the Columbia River, Washington.

Strontium-90 ((90)SR) released to the ground near the N Reactor at the U.S. Department of Energy's Hanford Site enters the Columbia River through shoreline seeps. The (90)Sr is then potentially available for uptake by plants and animals. The life history and foraging behavior of nesting Canada geese is such that female geese could ingest (90)Sr while foraging on shoreline plants. Radichemical analyses showed that goose eggshells taken from an island, downstream from the N Reactor, contained more (90)Sr than did eggshells collected from other downstream islands. Reed canary grass samples taken from shoreline areas immediately downstream from the N Reactor contained higher concentrations of (90)Sr than samples from other downstream areas. All goose eggshells did not contain enhanced levels of (90)Sr, and all reed canary grass samples did not contain enhanced levels of (90)Sr, but a relationship exists between the releases of (90)Sr to the Columbia River and the enhanced levels of (90)Sr in some of the environmental samples analyzed.

Trees as indicators of subterranean water flow from a retired radioactive waste disposal site.

Tree sampling helped locate a subterranean flow of tritiated water from a low-level radioactive waste disposal site that had not been detected by well water monitoring alone. Deciduous trees growing in a natural forest on the hillsides downslope from the site were sampled for the presence of tritiated water in sap of maple trees and in leaf water extracted from oak and hickory trees. Elevated concentrations of 3H were detected in the leaf water extracted from several trees located 50 m downslope from the western boundary of the fenced exclusion zone. A 3-m-deep well drilled near these trees indicated that the source of tritiated water was a narrow zone of subterranean flow.

Iodine in terrestrial wildlife on the U.S. department of energy's Hanford Site in southcentral Washington.

Iodine-129 in controlled amounts has been released into the air from the operating chemical separations facilities on the Hanford Site. Small amounts of (129)I have accumulated in surface soils especially at locations near the chemical separations facilities. Enriched levels of (129)I also occur in the thyroid glands of mule deer (Odocoileus hemionus) residing on the Hanford Site.Stable iodine is present in low concentrations in Hanford Site soils and it is not avidly accumulated by wild plants. Soils at high elevations have greater concentrations of (127)I than low elevations soils. Mule deer thyroids had higher concentrations of stable iodine than the thyroids of black-tailed jackrabbits. Stable iodine in black-tailed jackrabbit thyroids varied with the season with maximal concentrations in summer.Iodine-131 has not been released into the air from operating chemical separations facilities for more than 10 yr. Because of its short half-life (131)I of Hanford Site origin has disappeared from the Hanford Site. In the event of a future restart of the chemical separations facilities black-tailed jackrabbits can be used as biological indicators of (131)I in the terrestrial environment of the Hanford Site.

Excrement from Heron colonies for environmental assessment of toxic elements.

Excrement cast from Great Blue Heron nests was collected during the nesting period of 1978 from four colonies in Washington and Idaho. Cheesecloth strips placed on the ground beneath the nests served as excrement collecting devices. Chemical analysis for lead, mercury and cadmium were performed on dried samples. Lead was the most abundant trace metal found in heron debris. The Idaho colony at Lake Chatcolet had an average concentration of 46 ppm in the beneath-nest samples and 6 ppm in control samples. A heron colony near Tacoma, Washington had beneath-nest samples averaging 28 ppm and control samples averaging 20 ppm. Two colonies located in the interior region of Washington had substantially lower concentrations of lead. The difference observed between colonies was attributed to their associations with a polluted watershed (Chatcolet colony) an interstate highway (Tacoma colony) and an unpopulated largely agricultural area (inland Washington).

Elk in the shrub-steppe region of washington: an authentic record.

For the first time in recorded history, the American elk is established in the treeless interior region of Washington. The protective isolation provided by the large buffer zone around the Hanford facilities of the U.S. Energy Research and Development Administration is the important factor in maintenance of suitable habitat for elk.