This thesis was prepared by Tyler Maynard and Hayley Monroe, who are students at Arizona State University studying to complete their B.S.E.s in Civil Engineering and Construction Engineering, respectively. Both students are members of Barrett, the Honors College, at Arizona State University, and have prepared the following document for the purpose of completing their undergraduate honors thesis. The early sections of this document comprise a general, introductory overview of earthquakes and liquefaction as a phenomenon resulting from earthquakes. In the latter sections, this document analyzes the relationship between the furthest hypocentral distance to observed liquefaction and the earthquake magnitude published in 2006 by Wang, Wong, Dreger, and Manga. This research was conducted to gain a greater understanding of the factors influencing liquefaction and to compare the existing relationship between the maximum distance for liquefaction and earthquake magnitude to updated earthquake data compiled for the purpose of this report. As part of this research, 38 different earthquake events from the Geotechnical Extreme Events Reconnaissance (GEER) Association with liquefaction data were examined. Information regarding earthquake depth, distance to the furthest liquefaction event (epicentral and hypocentral), and earthquake magnitude (Mw) from recent earthquake events (1989 to 2016) was compared to the previously established relationship of liquefaction occurrence distance to moment magnitude. The purpose of this comparison was to determine if recent events still comply with the established relationship. From this comparison, it was determined that the established relationship still generally holds true for the large magnitude earthquakes (magnitude 7.5 or above) that were considered herein (with only 2.6% falling above the furthest expected liquefaction distance). However, this relationship may be too conservative for recent, low magnitude earthquake events; those events examined below magnitude 6.3 did not approach established range of furthest expected liquefaction distance. The overestimation of furthest hypocentral distance to liquefaction at low magnitudes suggest the empirical relationship may need to be adjusted to more accurately capture recent events, as reported by GEER.

This report analyzes the potential for accumulation of boron in direct potable reuse. Direct potable reuse treats water through desalination processes such as reverse osmosis or nanofiltration which can achieve rejection rates of salts sometimes above 90%. However, boron achieves much lower rejection rates near 40%. Because of this low rejection rate, there is potential for boron to accumulate in the system to levels that are not recommended for potable human consumption of water. To analyze this issue a code was created that runs a steady state system that tracks the internal concentration, permeate concentration, wastewater concentration and reject concentration at various rejection rates, as well as all the flows. A series of flow and mass balances were performed through five different control volumes that denoted different stages in the water use. First was mixing of clean water with permeate; second, consumptive uses; third, addition of contaminant; fourth, wastewater treatment; fifth, advanced water treatments. The system cycled through each of these a number of times until steady state was reached. Utilities or cities considering employing direct potable reuse could utilize this model by estimating their consumption levels and input of contamination, and then seeing what percent rejection or inflow of makeup water they would need to obtain to keep boron levels at a low enough concentration to be fit for consumption. This code also provides options for analyzing spikes and recovery in the system due to spills, and evaporative uses such as cooling towers and their impact on the system.