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Portland, OR, United States

Staheli K.,Staheli Trenchless Consultants | Moore B.,Staheli Trenchless Consultants | Eder A.,Kennedy Jenks Consultants | Holland J.,Brown and Caldwell | And 2 more authors.
Pipelines 2014: From Underground to the Forefront of Innovation and Sustainability - Proceedings of the Pipelines 2014 Conference | Year: 2014

A large water supply pipeline has been designed to carry water from the Willamette River in Gladstone, Oregon, to the cities of Lake Oswego and Tigard, Oregon. The pipeline ranges in diameter from 24 to 48 in. and traverses more than 10 mi. The pipeline was part of an overall water supply project that included a raw water intake, a raw water pipeline, a water treatment plant, a finished water pipeline, and a reservoir. Finding a route for the pipeline was challenging as it traversed through many cities and required a number of interagency agreements. Along with the routing challenges, there were many technical challenges such as crossing beneath the Willamette River. This crossing is 36-in. in diameter through basalt that varies in unconfined compressive strength exceeding 40,000 psi. An extensive trenchless evaluation was performed to determine the method that offered the highest chance of success with the lowest overall risk profile. Horizontal directional drilling (HDD) was chosen as the preferred trenchless installation technique. The length of the river crossing is 3,800 ft, making the 36-in. diameter rock drill very challenging. In addition to the challenges of the drill, site and pipe layout was very restricted, further complicating and increasing the risk of the project. Many aspects of the drill had to be thoroughly laid out during design, leaving little flexibility to the contractor. This paper discusses the design of the project, the risk aspects of the horizontal directional drill and microtunneling alternatives, and the decision process leading to the selection of the trenchless technology. © 2014 American Society of Civil Engineers.

Ryder R.A.,Kennedy Jenks Consultants
American Water Works Association Annual Conference and Exposition 2011, ACE 2011 | Year: 2011

There are many instances where ground water wells have relatively low pH and high carbon dioxide concentrations. Some cause Lead and Copper Rule copper action levels over the limit, some aesthetic blue water staining or metallic tastes, others cause copper pipe pitting, while others copper concentrations in wastewaters that even after wastewater treatment cause exceedance of the very low copper concentrations of many new waste discharge permits. Aeration stripping of CO2 is often utilized; but usually requires a break of hydraulic head and often double pumping. Space limitations and energy costs can be significant. Chemical prices and particularly caustic soda and soda ash have tripled in recent years. An evaluation of alternative aeration stripping by packed towers, tray aerators, low profile diffused air, piped eductors and spray nozzles are presented for 100,500 and 1,000 gpm wells. Evaluations include capital costs, size foot prints, energy and O&M costs. Chemical alternatives of caustic soda, soda ash, sodium phosphate, blended ortho-polyphosphate and zinc orthophosphate are also evaluated. Examples of four different small water utilities and of more than twenty wells are included in the analyses.

Drago J.A.,Kennedy Jenks Consultants | Carpenter A.T.,AWWA
Journal - American Water Works Association | Year: 2013

Sequestration of carbon dioxide in underground geologic formations is an emerging technology for mitigating greenhouse gas emissions to reduce the magnitude and potential effects of climate change. The technology is a key component of an overall strategy referred to as carbon capture and storage for reducing carbon dioxide emission from industrial sources such as fossil fuel power plants and refineries. The primary commercial process involves capturing carbon dioxide from industrial sources, transporting it by pipeline to an injection site, and injecting it into a geologic formation for long-term storage. Geologic sequestration refers to the portion of this process in which carbon dioxide is injected into a geologic formation suitable for long-term containment.

Hope B.K.,11 SW Sixth Avenue | Stone D.,Oregon State University | Fuji T.,Kennedy Jenks Consultants | Gensemer R.W.,4601 Denver Technology Center Blvd | Jenkins J.,Oregon State University
Integrated Environmental Assessment and Management | Year: 2010

In 2007, the State of Oregon enacted legislation aimed at identifying persistent pollutants that could pose a threat to waters of the State and then reducing their discharge by means of a comprehensive pollution prevention program. This legislation defined a persistent pollutant as one that is toxic and persistent or bioaccumulative; a broad definition that required evaluation of an extensive number and variety of chemicals. The Oregon Department of Environmental Quality, in consultation with a science workgroup, implemented a 12-step process for identifying and prioritizing persistent pollutants consistent with this definition. This process is characterized by (a) maximum overall transparency in its conduct, including extensive public involvement, (b) 3 levels of objective and predefined criteria for categorization of a chemical as a persistent pollutant, (c) full disclosure of values and sources for all physicochemical data used for comparison with these criteria, and (d) clear acknowledgement when a chemical was identified as a persistent pollutant for reasons other than these criteria alone. This process was used to identify those chemicals relevant as persistent pollutants and to then prioritize them in terms of their relative ability to adversely impact waters of the state, with special emphasis on impacts to aquatic receptors. An initial list of 2130 chemicals was compiled from existing lists. Criteria for toxicity, persistence, and bioaccumulative potential were defined and then used with 2 different chemical property evaluation models (PBT Profiler and EPISuite) to produce a final list of 118 chemicals. The final list includes several legacy pollutants but also contains numerous current-use pharmaceuticals, personal care products, and pesticides, approximately half of which appear only once or not at all on lists compiled by others. Although it drew from the experience of others, assembling this list proved to be an exemplar of science in the service of policy. © 2010 SETAC.

Smeraldi J.,University of California at Irvine | Ganesh R.,Kennedy Jenks Consultants | Safarik J.,Fountain | Rosso D.,University of California at Irvine
Journal of Environmental Monitoring | Year: 2012

The dynamic light scattering (DLS) technique can detect the concentration and size distribution of nanoscale particles in aqueous solutions by analyzing photon interactions. This study evaluated the applicability of using photon count rate data from DLS analyses for measuring levels of biogenic and manufactured nanoscale particles in wastewater. Statistical evaluations were performed using secondary wastewater effluent and a Malvern Zetasizer. Dynamic light scattering analyses were performed equally by two analysts over a period of two days using five dilutions and twelve replicates for each dilution. Linearity evaluation using the sixty sample analysis yielded a regression coefficient R 2 = 0.959. The accuracy analysis for various dilutions indicated a recovery of 100 ± 6%. Precision analyses indicated low variance coefficients for the impact of analysts, days, and within sample error. The variation by analysts was apparent only in the most diluted sample (intermediate precision ∼12%), where the photon count rate was close to the instrument detection limit. The variation for different days was apparent in the two most concentrated samples, which indicated that wastewater samples must be analyzed for nanoscale particle measurement within the same day of collection. Upon addition of 10 mg l -1 of nanosilica to wastewater effluent samples, the measured photon count rates were within 5% of the estimated values. The results indicated that photon count rate data can effectively complement various techniques currently available to detect nanoscale particles in wastewaters. © 2012 The Royal Society of Chemistry.

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