As a result of the most recent recalculation one of the indicator parameters, specific conductance, exceeded its background value in downgradient well 299-W19-41, triggering a change from detection monitoring to groundwater quality assessment program. The major contributors to the higher specific conductance are nonhazardous constituents (i.e., sodium, calcium, magnesium, chloride, sulfate, and bicarbonate). Nitrate, chromium, and technetium-99 are present and are increasing; however, they are significantly below their drinking waster standards. Interpretation of groundwater monitoring data indicates that both the nonhazardous constituents causing elevated specific conductance in groundwater and the tank waste constituents present in groundwater at the waste management area are a result of surface water infiltration in the southern portion of the facility. There is evidence for both upgradient and waste management area sources for observed nitrate concentrations. There is no indication of an upgradient source for the observed chromium and technetium-99.

Waste Management Area U (TWA U) is located in the 200 West Area of the Hanford Site. The area includes the U Tank Farm, which contains 16 single-shell tanks and their ancillary equipment and waste systems. WMA U is regulated under the Resource Conservation and Recovery Act of 1976 (RCRA) as stipulated in 40 CFR Part 265, Subpart F, which is incorporated into the Washington State dangerous waste regulations (WAC 173-303400) by reference. Groundwater monitoring at WMA U has been guided by an interim status indicator evaluation program. As a result of changes in the direction of groundwater flow, background values for the WMA have been recalculated several times during its monitoring history. The most recent recalculation revealed that one of the indicator parameters, specific conductance, exceeded its background value in downgradient well 299-W19-41. This triggered a change from detection monitoring to a groundwater quality assessment program. The major contributors to the higher specific conductance are nonhazardous constituents, such as bicarbonate, calcium, chloride, magnesium, sodium and sulfate. Chromium, nitrate, and technetium-99 are present and are increasing; however, they are significantly below their drinking water standards. The objective of this study is to determine whether the increased concentrations of chromium, nitrate, …

This report covers the accomplishments of the home energy ratings systems/energy-efficient mortgages (HERS/EEMs) pilot states from 1993 through 1998, including such indicators as funding, ratings and EEMs achieved, active raters, and training and marketing activities. A brief description of each HERS program's evolution is included, as well as their directors' views of the programs' future prospects. Finally, an analysis is provided of successful HERS program characteristics and factors that appear to contribute to HERS program success.