Documents

Phase I Environmental Site Assessment (ESA) for an approximately 60.4-hectare (149.3-acre) site in Maricopa County, Arizona (6L Ranch).

This technical memorandum was prepared to summarize results of drilling, construction, equipping, and testing at hydrologic test wells HRES-10 and HRES-11. The wells were installed to characterize hydrogeologic conditions in the Apache Leap Tuff (Tal) in the southeast extent of the Tal outcrop area near Mineral Creek. Monitoring data obtained from HRES-10 and HRES-11 will be incorporated into the RCM hydrologic monitoring program.

This test method covers a procedure that accelerates the natural weathering rate of a solid material sample so that diagnostic weathering products can be produced, collected, and quantified. Soluble weathering products are mobilized by a fixed-volume aqueous leach that is performed, collected, and analyzed weekly. When conducted in accordance with the following protocol, this laboratory test method has accelerated metal-mine waste-rock weathering rates by at least an order of magnitude greater than observed field rates.

The basic objective of this guide is to help engineers, planners, environmental specialists, and road managers make good decisions, protect the environment, and build good low-volume roads.

This report summarizes the meteorological, upper air, nitrogen dioxide (NO2), sulfur dioxide (SO2), ozone (O3), and particulate matter (PM) data collected at the Resolution Copper Project near Superior, Arizona for the first quarter, January 1 – March 31, 2016.

We present a new empirical ground motion model for PGA, PGV, PGD and 5% damped linear elastic response spectra for periods ranging from 0.01–10 s. The model was developed as part of the PEER Next Generation Attenuation (NGA) project. We used a subset of the PEER NGA database for which we excluded recordings and earthquakes that were believed to be inappropriate for estimating free-field ground motions from shallow earthquake mainshocks in active tectonic regimes.

This paper compares a number of approximations used to estimate means and variances of continuous random variables and/ or to serve as substitutes for the probability distributions of such variables, with particular emphasis on three-point approximations.

We present tectonic reconstructions and an accompanying animation of deformation across the North America–Pacific plate boundary since 36 Ma.

The Frazier Mountain paleoseismic site is located on a poorly understood section of the southern San Andreas fault, mid-way between the well-known Carrizo Plain and Mojave sites of Bidart Fan and Pallett Creek. Emerging paleoseismic evidence indicates that earthquakes along this stretch repeat at a similar pace, with an average interval of - 122 years between AD. 1000 and 1857.

Lake Roberts Dam is located in Grant County in southwestern New Mexico. Tectonically the damsite is within the Southern Basin and Range Province and the Rio Grande rift as defined by Machette (1998). Although the historical seismicity in the region has been low, the site has undoubtedly been shaken by past large prehistoric earthquakes caused by active regional faults and in historical times, as recently as 1887 (Figures 2 to 4).