Tetra Tech Research Articles

Preface: Recent Findings in Mercury Health Effects

The four articles in this mini-monograph represent a cross-section of results from human studies on mercury exposure and health outcomes presented at the most recent International Conference on Mercury as a Global Pollutant (ICMGP) held 28 June to 2 July 2004 in Ljubljana, Slovenia. The ICGMP provides a needed global forum for the exchange of innovative ideas, and it provides an opportunity to communicate research results to public policy makers, industry experts, and public representatives in order to promote the direct use of scientific and technical data to environmental protection and control. Intense interest in mercury is evident from the recommendations adopted by the European Union Mercury Strategy in June 2005 (European Union 2005); also, a Global Mercury Assessment was approved by the Governing Council of the United Nations Environmental Program in early 2002. The 7th ICMGP was held in Ljubljana, Slovenia, the location of the second largest mercury mine in the world—the Idrija mercury mine. Although the mercury mine was the basis of prosperity of the town of Idrija for five centuries, it also caused extensive contamination of the town and its surroundings, leading to high levels of mercury exposure of the miners and the other inhabitants. The mercury mine was closed in the mid-1980s to avoid further releases of mercury to the environment. Mercury research in Slovenia was initiated by the Jožef Stefan Institute in the early 1960s as a result of environmental and health concerns related to the operation of the mine. Initially, the main goal of the institute was to address the health status of the miners. Studies of the effects of mercury on the environment soon followed, and results have been published widely in the scientific literature. The 7th ICMGP consisted of more than 600 scientific presentations, with nearly 500 participants from more than 40 countries, and covered a wide range of topics including analytical chemistry, biogeochemistry, atmospheric science, health effects, and remediation and policy issues. The conference was sponsored by a several Slovenian institutes, ministries, and businesses, including the Jožef Stefan Institute, Ministry of Education Science and Sport, Ministry of Health, Ministry of the Environment and Physical Planning, Thermo Power plant Sostanj, Salonit Anhovo, Slovenian Tourist Board, Ljubljana Turist Board, Mercury Mine Idrija, Cankarjev Dom. International sponsors included Ina Naftaplin, the U.S. Environmental Protection Agency, the Electric Power Research Institute, Tetra Tech, Inc., Tekran Inc., Oak Ridge National Laboratory , Forschungszentrum Geesthacht GmbH (GKSSl), United Nations Environmental Program, Exponent, Global Environmental Facility/United Nations Development Programme/United National Industrial Development Organization (GEF/UNDP/UNIDO), (EUROCHLOR); National Institute for Minamata Disease, CEBAM Analytical Inc., Lumex, and International Research Development Center of Canada. Information on the 8th International Conference on Mercury as Global Pollutant is available online (http://www.mercury2006.org). Two studies in this mini-monograph address human exposure and outcomes related principally to elemental mercury vapors from past mercury mining operations (Kobal et al. 2006) and current high ambient exposures in China due to mercury mining, ore processing, coal combusion, and chloralkali plant operations (Chen et al. 2006) The other two studies address human exposure to methylmercury that occurred principally via fish consumption (Canual et al. 2006; Spurgeon 2006). Together, these articles provide a cross-section of the highly active area of environmental health research regarding exposure to inorganic and organic mercury and health outcomes. Results of the studies provide counter-intuitive insights into the complexities regarding exposure and health effects. For example, although exposure to extremely high levels of mercury in the 18th century hat-making industry led to the “mad as a hatter” syndrome, relatively long-term, considerably lower exposure in the mercury mining industry does not appear to be directly associated with untoward personality traits. Investigation of interactions in vivo between selenium and mercury pointed to likely protective pathways in humans; this interaction has been previously predicted in vitro. Risk assessment methods generally assume that mercury hair levels directly reflect total mercury intake and most especially methylmercury intake from fish consumption. Results from the study of distinct populations in eastern Canada indicate that a considerable number of additional factors need to be determined and considered. Most important, these results imply that a direct linear relation between hair mercury and methylmercury intake cannot always be assumed. And finally, an evidence-based review of epidemiology studies of in utero methylmercury exposure and child developmental outcomes indicates that because of large uncertainties in both exposure assessment and outcome measures across studies, firm conclusions cannot be reached at this time as to whether there is or is not an effect on child neurobehavioral and developmental outcomes at relatively low levels of exposure.

Carbonate reservoir characterization and simulation: From facies to flow units

Chip Feazel is principal carbonate stratigrapher for ConocoPhillips, with worldwide responsibility for interpreting carbonate depositional and diagenetic histories to predict reservoir properties. Following undergraduate studies at Ohio Wesleyan University, he received his M.A. degree and his Ph.D. in geology from Johns Hopkins University. In 29 years with Phillips, subsequently ConocoPhillips, he has enjoyed a variety of technical and managerial assignments in the United States and overseas in field development and technology teams.Alan Byrnes has been a research geologist at the Kansas Geological Survey since 1997, where he works on lithologic controls on rock petrophysical properties, CO2-enhanced oil recovery, reservoir characterization, and modeling. Alan received his B.S. degree in geology from the University of Illinois at Chicago and his M.S. degree in geophysical sciences from the University of Chicago. He has been a research geologist at the Institute of Gas Technology, Marathon Oil Company Research Center, Core Laboratories, and Tetra Tech, and for 13 years, he owned and operated GeoCore, a special core analysis laboratory in Colorado. With more 30 years in the oil and gas industry, Jim Honefenger has worked in virtually every segment, starting in 1972 with Elliott Company, a turbomachinery manufacturer. He held senior management positions for Scientific Software Intercomp, Intera, Energy Systems, GeoQuest Schlumberger, Western Atlas, Landmark Graphics, GeoNet Services, and Veritas Exploration Services, developing the market for geophysical, geological, petrophysical, reservoir engineering, and pipeline simulation products. More recently, he sold the intellectual assets of (RC)2 and founded his own company, Consulting Assets, representing oil and gas industry-consulting firms located throughout the world. Honefenger is an active Society of Petroleum Engineers (SPE) member and has held various positions in both the international and local groups. A cofounder of the Houston Energy Council (a professional organization comprising board members from Houston Geological Society, Geophysical Society …

Tetra Tech awarded US$7m water contracts

Development of crash prediction models at the county-level has drawn the interests of state agencies for forecasting the normal level of traffic safety according to a series of countywide characteristics. A common technique for the county-level crash modeling is the generalized linear modeling (GLM) procedure. However, the GLM fails to capture the spatial heterogeneity that exists in the relationship between crash counts and explanatory variables over counties. This study aims to evaluate the use of a Geographically Weighted Poisson Regression (GWPR) to capture these spatially varying relationships in the county-level crash data. The performance of a GWPR was compared to a traditional GLM. Fatal crashes and countywide factors including traffic patterns, road network attributes, and socio-demographic characteristics were collected from the 58 counties in California. Results showed that the GWPR was useful in capturing the spatially non-stationary relationships between crashes and predicting factors at the county level. By capturing the spatial heterogeneity, the GWPR outperformed the GLM in predicting the fatal crashes in individual counties. The GWPR remarkably reduced the spatial correlation in the residuals of predictions of fatal crashes over counties.

INTER-JURISDICTIONAL ISSUES IN THE DEVELOPMENT OF MINING RELATED TMDLS FOR THE TUG FORK RIVER WATERSHED

INTER-JURISDICTIONAL ISSUES IN THE DEVELOPMENT OF MINING RELATED TMDLS FOR THE TUG FORK RIVER WATERSHEDMining related impairments affect nearly 500 waterbodies in West Virginia. EPA Region 3, with the support of West Virginia Department Environmental Protection (WVDEP) and Tetra Tech, Inc. have developed TMDLs for two thirds of the mining impaired waterbodies in West Virginia to meet the requirements of a 1997 consent decree. TMDL development addressed a variety of case-specific requirements...Author(s)Thomas HenryPatrick CampbellDave MontaliJames GreenfieldGeorge O'QuinnJon LudwigClary Barreto-AcobeSourceProceedings of the Water Environment FederationSubjectSession 16 Water Quality TradingDocument typeConference PaperPublisherWater Environment FederationPrint publication date Jan, 2002ISSN1938-6478SICI1938-6478(20020101)2002:8L.1436;1-DOI10.2175/193864702785072425Volume / Issue2002 / 8Content sourceTMDLS ConferenceFirst / last page(s)1436 - 1446Copyright2002Word count410

Emerging Institutions for Bilateral Management of the Columbia River Basin

Historically, binational governance of the Columbia River Basin has been controlled by federal agencies in the United States and federal-provincial agencies in British Columbia, both supported by the International Joint Commission. While this management system has served the region well for many years, it is now showing signs of strain. In both countries, stakeholders have identified a number of issues of concern, including the narrowness of the Columbia River Treaty. At the same time, there are pressures to create new management goals and more balanced systems of river basin planning and governance. Both countries are attempting to respond to a range of unresolved problems and concerns individually at the national level and bilaterally in the transboundary context. In this paper, we explore a spectrum of possible management outcomes that could emerge in the current search for a new consensus. All relate to questions of the values that should be sustained, and to the nature of an acceptable binational governance framework needed to achieve such values. The Context The Columbia basin has been used by societies in a variety of ways. Beginning as a provider of sustenance, water, and as a transportation artery for native peoples who first inhabited the area, its functions gradually evolved during the nineteenth and twentieth centuries to include large-scale commercial fisheries, transportation, water supplies, hydroelectricity, and recreation. Beginning in the 1930s, federal dams were built on the Columbia and its tributaries, while many nonfederal projects were devised to support the numerous uses of the basin by diverting, regulating, and storing water for consumptive and instream uses (United States, BPA 1991, 5). Investment in these dams and the related infrastructure has enabled many uses to coexist. In recent years, the basin has been described not only as a scenic treasure and ecological gem, but also as the economic backbone of the entire Pacific Northwest in the United States and central interior of British Columbia (Tetra Tech 1996, 1). Although high technology industries such as aerospace engineering, scientific instruments, and computer programming now contribute 42 percent of all employment in the basin south of the 49th parallel (United States 1995c, 2-7), the Columbia basin remains a supplier of many raw materials and semifinished manufactured goods (United States 1995c, 2-1). Average runoff from the Columbia is 198 million acre feet (maf) (275,022 cubic feet per second) at the mouth, making the Columbia's discharge second only to the Missouri-Mississippi River in the United States (United States 1995b, 1-1). The river originates in central British Columbia in the Rocky Mountains. Its waters flow 1,214 miles (1,954 km) to the Pacific Ocean near Astoria, Oregon, making it the fourth longest river on the continent. Its drainage basin covers 219,000 square miles (567,200 km2) in seven states, which include Washington, Oregon, Idaho, Montana, and small parts of Wyoming, Nevada, and Utah, as well as 39,500 square miles (79,000 km2) in the province of British Columbia (United States 1995a, 2; Coulson 1996, 2) (fig. 1). Natural stream flows on the Columbia have fluctuated enormously. Prior to construction of the basin's storage dams, the river's volatile waters regularly flooded, destroying portions of communities situated on dangerous flood plain locations along its banks, causing death and the destruction of property and real estate. Reservoirs were constructed to act as a safety buffer and help prevent these disasters. They created adequate storage space for times when the river is at high levels. Today, flood control takes priority over all other uses (British Columbia 1993b, 2). Given this context, a variety of mechanisms were created, mostly during this century, to govern the resources in the Columbia, separately in each country as well as binationally. From relatively simple systems initially, these have grown into increasingly complex, overlapping institutions. …

SHORE PROTECTION PLAN FOR THE NILE DELTA COASTLINE

A Shore Protection Master Plan (SPMP) for the Nile Delta Shoreline, extending from 30 kms west of the city of Alexandria (Arab Republic of Egypt) to 30 kms east of Port Said, is developed and reported. The SPMP was developed in three stages: (1) collection and analysis of relevant data to identify existing and future coastal problems and limits of needed shore protection, (2) development of shore protection alternatives with costs and economic evaluations, and (3) detailed design and technical specifications for the selected shore protection schemes along the SPMP zone. This paper summarizes Tetra Tech, Inc./Honeywell work and achievements on this project while under contract with the Egyptian Shore Protection Authority (SPA). The SPMP considered the Egyptian Government and the SPA national needs to the year 2000.

Anisotropic multiple scattering of collimated irradiance: W. H. Wells and J. J. Sidorowich. Tetra Tech. Inc., Pasadena, California 91107.

Anisotropic multiple scattering of collimated irradiance: W. H. Wells and J. J. Sidorowich. Tetra Tech. Inc., Pasadena, California 91107.

Fracture Analysis of Eastern Ohio: ABSTRACT

Selected shale characterization exploration parameters defined from Eastern Gas Shales Project investigations to identify highly potential Devonian shale exploration areas were used by Tetra Tech, Inc., to select drilling sites in the Appalachian, Michigan, and Illinois basins. The characterization parameters used for site selection were: (1) thickness of the shales, (2) type of organic matter, (3) percent of organic carbon, (4) thermal maturation, and (5) the presence of secondary natural-fracture porosity. The fracture analysis investigation over eastern Ohio using remote sensing techniques describes a method which should prove useful for locating secondary natural-fracture porosity reservoirs in regions of horizontal or slightly dipping strata. Detailed field checks over a pilot area in Hocking County, Ohio, indicated that approximately 50% of mapped photo linears were not fracture related. A hypothetical interpretive technique developed to identify only the fracture-related photo linears was used in interpreting and mapping fractures over the entire area of eastern Ohio. Statistical analysis of this data was necessary due to the large volume of data. A computer program was developed that analytically distinguished the regional and local components of the data. Computer-generated first and second-degree and corresponding residual maps showed areas of eastern Ohio where fracture density exceeded or was less than the regional norm. End_Page 1175------------------------------ High-density fracture areas, located within high-potential exploration areas (as defined by the other four exploration parameters), should have high potential for Devonian shale or Clinton sandstone natural gas production. End_of_Article - Last_Page 1176------------