A semi-Markov model estimating the waiting times and magnitudes of large earthquakes is proposed. The model defines a discrete-time, discrete-state process in which successive state occupancies are governed by the transition probabilities of the Markov process. The stay in any state is described by an integer-valued random variable that depends on the presently occupied state and the state to which the next transition is made. Basic parameters of the model are the transition probabilities for successive states, the holding time distribution, and the initial conditions (the magnitude of the most recent earth-quake and the time elapsed since then). The model was tested by examining compatibility with historical seismicity data for large earthquakes in the circum-Pacific belt. The examination showed reasonable agreement between the calculated and actual waiting times and earthquake magnitudes. The proposed procedure provides a more consistent model of the physical process of gradual accumulation of strain and its intermit-tent, nonuniform release through large earthquakes and can be applied in the evaluation of seismic risk.

In the three decades during which predominately white institutions of higher education have been desegregated, some important gains have been made, although in regards to matters of race, serious problems and difficulties continue to exist. One important index of progress is the elevation of African Americans to significant positions within the hierarchy of administrative structures at predominately white colleges and universities (Harvey, 1999, p. 1). White people continue to dominate the administrative group of colleges and universities. In 1997 white men held 47 % of the more than 151,000 executive, administrative, and managerial staff positions. White women accounted for 38 % of the positions, black men accounted for 4 % of the positions and black women held 5 % of the positions. Hispanics, Native Americans, Asian Americans, and Pacific Islanders held another 5 % of the positions (U.S. Department of Education, 2001). However, evidence suggests that during the past decade and a half, gains have slowed (Glazer-Raymo, 1999), or there has been a constant or widening numerical gap between the number of positions held by white men and other groups (Slaughter, 1993). There are graphic differences among different racial groups (Lindsay, 1997; Harvey, 1999) An earlier version of this article was presented at the “Transformations: Thinking

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Abstract: Concentrations of halogenated volatile organic compounds �VOCs � were determined by gas chromatography �GC � with an electron-capture detector �GC-ECD � and by gas chromatography with mass spectrometry �GC-MS � in 109 groundwater samples from five study areas in the United States. In each case, the untreated water sample was used for drinking-water purposes or was from a monitoring well in an area near a drinking-water source. The minimum detection levels �MDLs � for 25 VOCs that were identified in GC-ECD chromatograms, typically, were two to more than four orders of magnitude below the GC-MS MDLs. At least six halogenated VOCs were detected in all of the water samples analyzed by GC-ECD, although one or more VOCs were detected in only 43 % of the water samples analyzed by GC-MS. In nearly all of the samples, VOC concentrations were very low and presented no known health risk. Most of the low-level VOC detections indicated post-1940s recharge, or mixtures of recharge that contained a fraction of post-1940s water. Concentrations of selected halogenated VOCs in groundwater from natural and anthropogenic atmospheric sources were estimated and used to recognize water samples that are being impacted by nonatmospheric sources. A classification is presented to perform vulnerability assessments at the scale of individual wells using the number of halogenated VOC detections and total dissolved VOC concentrations in samples of untreated drinking water. The low-level VOC detections are useful in vulnerability assessments, particularly for samples in which no VOCs are detected by GC-MS analysis.

Florida is located at the convergence of the subtropical and temperate climate zones (Chen and Gerber, 1990). The Gulfstream (a warm-water boundary current) has a major influence on water temperature and the transport of flora and fauna to the region (Jaap and Hallock, 1990). The Gulfstream intrudes into the Gulf of Mexico as the Loop Current and reverses flow to return to the Straits of Florida, joining the main body of the

6 the proposed new Corporate Average Fuel Economy (CAFE) standards and reasonable alternative

The purpose of this report is to document the overall state of water resources in the Great Miami River Watershed for 2009 with an emphasis on the buried valley aquifer and water quantity and quality data. WATER QUANTITY MCD operates and maintains an extensive hydrologic monitoring system. By tracking trends in precipitation, runoff, and groundwater levels, changes to the balance of the hydrologic system of the watershed are assessed. In 2009, MCD recorded below normal annual precipitation within the Great Miami River Watershed. The 2009 mean annual precipitation recorded for the Great Miami River Watershed was 0.96 inches below the long-term mean annual precipitation. The below normal precipitation contributed to below normal runoff in the Great Miami River and its tributary streams. The total annual runoff for the Great Miami River Watershed upstream of Hamilton was 2.03 inches below the long-term mean annual runoff. The annual groundwater recharge to aquifers is estimated for the Great Miami River Watershed from stream gaging records. Groundwater recharge in 2009 was estimated to be 1.90 inches below the long-term mean annual groundwater recharge. Groundwater elevations measured in

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Chemical treatment of sagebrush rangeland with herbicides has been utilized in the southwest United States for two decades and has improved overall rangeland conditions. Though sagebrush eradication allows for increased vegetative cover, reduced runoff, erosion, and sediment transport, the lack of monitoring and evaluation of grazing land after treatment has resulted in the need to gather baseline data on vegetation changes and sediment production. A small first-order drainage basin in Arroyo Chijuilla, an ephemeral stream near Cuba, NM, was chosen to study the effects of sagebrush treatment on sediment movement. Rainfall simulations on 1 m 2 plots were used to collect runoff data from a total of 36 plot-runs. Half of the simulations were performed over initially dry soil (dry run) whereas the other half were carried out over the partially saturated soil the following day (wet run). Additional vegetation assessments, erosion pins, infiltration measurements, and soil analyses were used to evaluate vegetation changes and soil properties on treated and untreated sagebrush rangeland. Chemical treatment resulted in significant decreases in sediment concentrations (kg/hamm) for both grass and three shrub plots. Dry runs between grass plots produced similar sediment yields, whereas wet runs showed a nine-fold increase in sediment yield from treated plots

partners with scientific and technical support. All reports in this series receive anonymous peer review. Cover graphic by Mi Ae Lipe-Butterbrodt Mention of trade names or commercial products does not constitute endorsement or recommendation for use by the U.S. Department of the Interior, U.S. Geological Survey. Multiyear Synthesis of the Fish Component