24.04.2015 Views

KIRTLAND AIR FORCE BASE ALBUQUERQUE, NEW MEXICO ...

KIRTLAND AIR FORCE BASE ALBUQUERQUE, NEW MEXICO ...

KIRTLAND AIR FORCE BASE ALBUQUERQUE, NEW MEXICO ...

SHOW MORE
SHOW LESS

You also want an ePaper? Increase the reach of your titles

YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.

<strong>BASE</strong>-WIDE PLAN<br />

the high nitrate levels have resulted in zones of low oxygen in the groundwater. Nitrates are consistently<br />

detected in groundwater samples collected from monitoring wells on Kirtland AFB and will continue to<br />

be monitored as part of current projects. The nitrate contamination on the base could potentially be<br />

flowing into the groundwater at the depression area in the northwestern portion of the base. Heavy<br />

pumping of the groundwater by Kirtland AFB and the city of Albuquerque has caused this depression.<br />

The USGS has also identified exceedances of drinking water standards for dissolved solids, sulfate,<br />

chloride, iron, and manganese in eastern Bernalillo County. Concentrations of these constituents<br />

increased significantly during the 1990s as water levels in the area dropped (USGS, 1996). A major<br />

source of dissolved solids in the basin is reported to be calcite, gypsum, and halite in the basin fill<br />

sediments (Houser, 1999). A study of water in the Tijeras Arroyo indicated that dissolved solids often<br />

exceeded 500 mg/L (Thomas, 1995).<br />

In a description of aquifers found in sediments that are generally resistant to weathering (resistate<br />

aquifers), Hem (1989) describes waters in the Santa Fe Formation of the Albuquerque Basin. Some of the<br />

waters from this formation have very low solids content resulting from interaction with silica-rich<br />

igneous rocks; however, the major ion concentrations found in many of the Kirtland AFB wells,<br />

particularly the perched aquifer, may represent waters that come from an aquifer with sluggish<br />

circulation due to the decreasing water volumes, as evidenced by the lowering of water levels in these<br />

units. In these waters, flushing of solutes is retarded, resulting in higher concentrations of major ions and<br />

probably trace metals.<br />

Elevated iron concentrations have been reported in groundwater from the Santa Fe Group in the<br />

Albuquerque area (Plummer, et al., Section R). Based on sequential extraction analyses, it is reported<br />

that iron arises from geochemical exchange with the aquifer rock materials. Sediments from three wells<br />

in the Santa Fe Group were exposed to various reagents to mimic weathering in order to estimate watersoluble,<br />

ligand- or anion-exchangeable fractions, and those less-mobile fractions from metal oxides,<br />

sulfide, and organic complexes, and silicates. The iron was primarily found in metal oxides and silicates.<br />

In contrast, iron from the lower Kachina Formation was primarily found in sulfide minerals.<br />

Elevated concentrations of selenium have been detected in the groundwater underlying Kirtland AFB.<br />

Selenium has been studied extensively in the Central Valley of California and other arid environments<br />

similar to the Albuquerque Basin where high volumes of irrigation water are used. Selenium has been<br />

shown to mobilize from evaporite minerals resulting in high concentrations in irrigation return flows.<br />

Selenium is not attenuated by the physical, chemical, and biological properties of the soil like other<br />

minerals in agricultural settings (Allen, Perdue, and Brown, 1993, p. 338).<br />

Kirtland Air Force Base<br />

Base-Wide Plans for the Environmental Restoration Program 19 April 2004

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!