Documents

The objective of this manual is to provide technical procedures for the estimation of flood discharges for the purposes of designing stormwater drainage facilities and regulating water-courses in Maricopa County.

Topics include land use, demographics, specific industry sectors, the role of non-labor income, the wildland-urban interface, the role of amenities in economic development, and payments to county governments from federal lands.

This paper introduces a method for the evaluation of the seismic risk at the site of an engineering project. The results are in terms of a ground motion parameter (such as peak acceleration) versus average return period. The method incorporates the influence of all potential sources of earthquakes and the average activity rates assigned to them.

Sieh and Jahns (1984) forecasted that the next moderate Parkfield earthquake might trigger a major earthquake along a fault segment greater than 30 km long southeast of Cholame. Their forecast assumed (1) the slip was 3–4 m in 1857 and characteristic of the segment; (2) a slip rate of 3.4 cm/yr; and (3) full strain release in earthquakes.

The frequency of occurrence of earthquakes with different seismic moments is expressed in terms of the rate of slip on a fault and to the largest seismic moment likely to occur in the region.

This study defines the distribution, grade, and quality of diatomite at the White Cliffs diatomite deposit, Mammoth, Arizona. The deposit is hosted in a lacustrine facies of the Quiburis Formation, a Miocene to Pliocene basin-fill sediment of the lower San Pedro Valley. The lake bed sediments are divided into three informal members, the Redington, White Cliffs, and Gust James. Diatomite is found only in the White Cliffs member, and three potential ore zones are defined.

Data describing the locations, slip rates, and lengths of Quaternary faults are the primary basis in this work for constructing maps that characterize seismic hazard in California. The expected seismic moment M^e₀ and the strength of ground shaking resulting from the entire rupture of each mapped fault (or fault segment) are estimated using empirical relations between seismic moment M₀, rupture length, source to site distance, and strong ground motions.

Phase I Environmental Site Assessment (ESA) for approximately 640 acres referred to as East Clear Creek. The property comprises the entirety of Section 9 in Township 14 North, Range 12 East relative to the Gila and Salt River Baseline and Meridian, in Coconino County, Arizona.

This screening analysis was prepared to determine the potential for occurrence of special-status species and/or the presence of designated or proposed critical habitat within the footprint of these federal actions in support of USFS and Cooperative Agency review of these activities under NEPA.

This biological evaluation (BE) supports an evaluation of an alternative tailings storage facility (TSF; the Project) located southeast of Superior and north of Kearny, Pinal County, Arizona. The purpose of this BE is to perform a screening analysis to determine the occurrence or potential to occur of special-status species and/or designated or proposed critical habitat in the proposed Project Area or its vicinity.