Accessibility, Connectivity, and Captivity: Impacts on Transit Choice

2003 ◽  
Vol 1835 (1) ◽  
pp. 1-9 ◽  
Author(s):  
Edward A. Beimborn ◽  
Michael J. Greenwald ◽  
Xia Jin
Keyword(s):  
Environmental Protection Agency ◽  
Mode Choice ◽  
Mode Selection ◽  
Department Of Energy ◽  
Choice Data ◽  
Mode Split ◽  
Land Information System ◽  
Transit Connectivity ◽  
Service Factors ◽  
The U.S

Travelers can be classified into two groups: choice users and captive users. Choice users select transit or automobile service when they view one option as superior, whereas captive users have only one travel option. Surprisingly, little is known about captivity effects on mode split models. This research examines the way transit service factors such as accessibility and connectivity relate to mode captivity and mode choice. Data for this investigation come from the Portland, Oregon, 1994 Household Activity and Travel Diary Survey, the Regional Land Information System for the Portland area, the U.S. Environmental Protection Agency fuel economy database, and the U.S. Department of Energy. Individual trip data were segmented into transit captive, automobile captive, and choice users based on information about private vehicle availability, transit connectivity, and distance from a transit stop. Traditional transit mode split models are compared with models that segment users into choice and captive groups. It was found that traditional models underestimate the variation in mode choice for captive users, while overestimating the attractiveness of transit for choice users. These results indicate that better transit forecasts can result if accessibility and connectivity are used to help identify captive users. Additionally, among choice transit users, differences in travel times between automobile and transit modes do little to influence mode selection, while walk access to transit has more effect than previously thought.

scholarly journals Repurposing Reverse Osmosis Concentrate as a Low-Cost Thermal Energy Storage Medium

2020 ◽  
Vol 8 (4) ◽  
pp. 31-40
Author(s):  
Reza Baghaei Lakeh ◽  
◽  
Christopher Salerno ◽  
Ega P. Herlim ◽  
Joseph Kiriakos ◽  
...  
Keyword(s):  
Energy Storage ◽  
Reverse Osmosis ◽  
Thermal Energy ◽  
Thermal Energy Storage ◽  
Environmental Protection Agency ◽  
Low Cost ◽  
Salt Content ◽  
Department Of Energy ◽  
Surface Discharge ◽  
The U.S

The reject of the reverse osmosis water treatment process (aka brine, concentrate, ROC) is a mixture of salts that are dissolved in high salinity water. The ROC is classified as an industrial waste by the U.S. Environmental Protection Agency and can face regulatory limitations on disposal. State-of-the-art of ROC disposal includes deep-well injection, surface discharge to rivers, discharge to the ocean, and evaporation ponds. In this study, the feasibility of using Reverse Osmosis Concentrate as a low-cost Thermal Energy Storage (TES) medium is explored by a techno-economic analysis. The normalized cost of TES (cost per unit volume of stored thermal energy) is estimated through a series of cost analyses and is compared to the cost targets of the U.S. Department of Energy for low-cost thermal energy storage. It was shown that the normalized cost of TES using ROC salt content is in the range of $6.11 to $8.73 depending on ROC processing methods.

A National Perspective: Establishing and Implementing a Characterization Program in the U.S. for Remote-Handled Transuranic Waste

2007 ◽  
Author(s):  
Roger Nelson ◽  
Alton D. Harris
Keyword(s):  
Dose Rate ◽  
Waste Disposal ◽  
Environmental Protection Agency ◽  
Department Of Energy ◽  
Surface Dose ◽  
Radiation Dose Rate ◽  
Characterization Methods ◽  
Dose Rates ◽  
Transuranic Waste ◽  
The U.S

The U.S. Department of Energy (DOE) is responsible for waste management from nuclear weapons production and operates the Waste Isolation Pilot Plant (WIPP) for permanent disposal of defense-generated transuranic waste (TRU), as authorized by Congress in 1979. Radioactive waste in the U.S. has historically been managed in one of two ways depending on its penetrating radiation dose rate. Waste with surface dose rates above 200 millirem/hour (0.002 sievert/hour) and waste that has been managed remotely (remote-handled). In 1992, Congress passed the WIPP Land Withdrawal Act, which created the regulatory framework under which DOE was to operate the facility, and authorized disposal of waste up to 1,000 rems/hour (10 Sievert/hour). Subsequently, DOE submitted applications to the Environmental Protection Agency (EPA), at the Federal level, for certification to operate WIPP, and to the New Mexico Environment Department (NMED), at the State level, for a hazardous waste permit. Both applications described the characterization methods that DOE proposed to use to ensure only compliant waste was shipped to WIPP. No distinction was employed in these methods concerning the surface dose rate from the waste. During the applications review, both regulatory agencies came to the conclusion in their approval that DOE had not demonstrated that remote-handled transuranic (RH-TRU) waste could be adequately characterized. Therefore, WIPP was only granted approval to begin waste disposal operations of waste with surface dose rates less than 200 millirem/hour (0.002 sievert/hour) — or contact-handled transuranic (CH-TRU) waste. Emplacement of CH-TRU waste in WIPP began March 26, 1999. However, WIPP was designed for disposal of both CH- and RH-TRU waste, with the RH-TRU waste in canisters emplaced in the walls of the underground disposal rooms and CH-TRU waste in containers in the associated open drifts. Therefore, as disposal rooms filled with CH-TRU waste, the space along the walls for RH-TRU waste disposal was lost. This made removal of the regulatory prohibition on RH-TRU waste a very high priority, and DOE immediately began an iterative process to change the two regulatory bases for RH-TRU waste disposal. These changes focused on how DOE could rely on CH-TRU characterization methods for adequate characterization of RH-TRU waste. On January 23, 2007, the first shipment of RH-TRU waste was finally received at WIPP. The revised EPA certification and NMED permit now both consider all waste characterization methods to be equally effective when applied to either CH- or RH-TRU waste, as DOE maintained in the original applications over 10 years ago.

Field Evaluation of High Voltage Electron Beam Technology for Treating VOC-Contaminated Groundwater. Part I: VOC Removals and Treatment Costs

1998 ◽  
Vol 3 (1) ◽  
Author(s):  
Franklin Alvarez ◽  
Kirankumar Topudurti ◽  
Michael Keefe ◽  
Chriso Petropoulou ◽  
Tim Schlichting
Keyword(s):  
South Carolina ◽  
Electron Beam ◽  
Organic Compounds ◽  
High Voltage ◽  
Environmental Protection Agency ◽  
High Energy ◽  
Department Of Energy ◽  
Innovative Technology ◽  
Beam System ◽  
The U.S

AbstractAs part of the Superfund Innovative Technology Evaluation program, the U.S. Environmental Protection Agency evaluated the High Voltage Environmental Applications, Inc. (HVEA), electron beam (E-beam) technology at the U.S. Department of Energy Savannah River Site (SRS) in Aiken, South Carolina. This technology irradiates water with a beam of high-energy electrons, causing the formation of three primary transient reactive species: aqueous electrons, hydroxyl radicals, and hydrogen radicals. Target organic compounds are either mineralized or broken down into low molecular weight organic compounds, primarily by these species. The E-beam system used for the evaluation is housed in an 8- by 48-foot trailer and is rated for a maximum flow rate of 50 gpm. During two different periods totaling 3 weeks in September and November 1994, about 70,000 gallons of SRS M-area groundwater contaminated with volatile organic compounds (VOCs) was treated with the E-beam system. The highest removal efficiencies (REs) observed for unsaturated chlorinated VOCs in groundwater - trichloroethene (TCE), tetrachloroethene (PCE), and cis-1,2-dichloroethene (1,2-DCE) - were >99, 99, and > 91%, respectively. REs ranged from 68 to > 98% for 1,1,1-trichloroethane (1,1,1-TCA), 1,2-dichloroethane (1,2-DCA), chloroform, and carbon tetrachloride (CCl

Waste as a Renewable Source of Energy: Current and Future Practices

2003 ◽  
Author(s):  
Karsten Millrath ◽  
Nickolas J. Themelis
Keyword(s):  
Research And Development ◽  
Environmental Protection Agency ◽  
District Heating ◽  
Department Of Energy ◽  
Environmental Benefits ◽  
Waste To Energy ◽  
Renewable Source ◽  
Energy Current ◽  
Reuse Options ◽  
The U.S

Municipal Solid Waste (MSW) has been recognized by several states as a renewable source of energy. Worldwide, about 130 million tons of MSW are combusted annually in waste-to-energy facilities that produce electricity and steam for district heating and also recover metals for recycling. While being linked to environmental pollution prior to the implementation of Maximum Available Control Technology (MACT) regulations, Waste-to-Energy (WTE) was recently named one of the cleanest sources of energy by the U.S. Environmental Protection Agency (EPA) and the U.S. Department of Energy (DOE). However, the WTE industry often faces resistance and preconceptions based on past experience rather than current performance. Due to economic considerations that do not include environmental benefits, most of the U.S. MSW still ends up in landfills despite the fact that for every ton of MSW landfilled greenhouse gas emissions increase by at least 1.2 tons of carbon dioxide. While implemented research and development strategies focused on emissions, there is still a tremendous need for more efficient yet durable combustion technologies including flue gas recirculation and oxygen enrichment, environmentally and economically competitive reuse options for WTE residues, and also public education. The importance of WTE in the universal effort for sustainable development and its need for research and development resources has led to the formation of the Waste-to-Energy Research and Technology Council. Its principal goal is to improve the economic and environmental performance of technologies that can be used to recover materials and energy from solid wastes. This paper provides an overview of the current worldwide WTE practices, predominant technologies, and current research for advancing WTE as a renewable source of energy in the U.S. and elsewhere.

scholarly journals 2019 Performance Assessment Calculations for the Recertification of the Waste Isolation Pilot Plant

2020 ◽  
Author(s):  
Todd Zeitler ◽  
James Bethune ◽  
Sarah Brunell ◽  
Dwayne Kicker ◽  
Jennifer Long
Keyword(s):  
Performance Assessment ◽  
Environmental Protection Agency ◽  
Pilot Plant ◽  
Department Of Energy ◽  
Waste Isolation Pilot Plant ◽  
New Information ◽  
Regulatory Limits ◽  
Underground Disposal ◽  
Wholly Owned Subsidiary ◽  
The U.S

<p>The Waste Isolation Pilot Plant (WIPP), located in southeastern New Mexico, has been developed by the U.S. Department of Energy (DOE) for the geologic (deep underground) disposal of transuranic (TRU) waste. Containment of TRU waste at the WIPP is regulated by the U.S. Environmental Protection Agency (EPA) according to the regulations set forth in Title 40 of the Code of Federal Regulations (CFR), Part 191. The DOE demonstrates compliance with the containment requirements according to the Certification Criteria in Title 40 CFR Part 194 by means of performance assessment (PA) calculations performed by Sandia National Laboratories (SNL). WIPP PA calculations estimate the probability and consequence of potential radionuclide releases from the repository to the accessible environment for a regulatory period of 10,000 years after facility closure.</p><p>The models used in PA are maintained and updated with new information as part of an ongoing process. Improved information regarding important WIPP features, events, and processes typically results in refinements and modifications to PA models and the parameters used in them. Planned changes to the repository and/or the components therein also result in updates to WIPP PA models. WIPP PA models are used to support the repository recertification process that occurs at five-year intervals following the receipt of the first waste shipment at the site in 1999.</p><p>The 2019 Compliance Recertification Application (CRA-2019) is the fourth WIPP recertification application submitted for approval by the EPA. A PA has been executed by SNL in support of the DOE submittal of the CRA-2019. Results found in the CRA-2019 PA are compared to those obtained in the 2014 Compliance Recertification Application (CRA-2014) PA in order to assess repository performance in terms of the current regulatory baseline. This presentation includes a summary of the changes modeled in the CRA-2019 PA, as well as the estimated releases over the assumed 10,000-year regulatory period. Changes incorporated into the CRA-2019 PA included repository planned changes, parameter updates, and refinements to PA implementation.</p><p>Overall, the total normalized releases for the CRA-2019 PA have increased at all probabilities compared to those from the CRA-2014 PA. Releases from each of the four potential release mechanisms tracked in WIPP PA (cuttings and cavings, spallings, releases from the Culebra formation, and direct brine releases) have also increased at all probability levels. Cuttings and cavings releases continue to dominate total releases at high probabilities and direct brine releases continue to dominate total releases at low probabilities. Although the calculated releases have increased, the total normalized releases continue to remain below regulatory limits. As a result, the CRA-2019 PA demonstrates that the WIPP remains in compliance with the containment requirements of 40 CFR Part 191.</p><p>Sandia National Laboratories is a multimission laboratory managed and operated by National Technology and Engineering Solutions of Sandia, LLC., a wholly owned subsidiary of Honeywell International, Inc., for the U.S. Department of Energy’s National Nuclear Security Administration under contract DE-NA0003525.. This research is funded by WIPP programs administered by the Office of Environmental Management (EM) of the U.S. Department of Energy. SAND2020-0131A</p>

An Update on Clearance Initiatives in the United States

2003 ◽  
Author(s):  
Jas Devgun ◽  
Harold Peterson ◽  
Cheryl Trottier
Keyword(s):  
United States ◽  
Environmental Protection Agency ◽  
The United States ◽  
Nuclear Industry ◽  
Department Of Energy ◽  
National Standards ◽  
National Standard ◽  
Solid Materials ◽  
Federal Level ◽  
The U.S

A number of initiatives have been underway in the United States in the past several years in the area of clearance of solid materials both at the federal level and at the industry and professional society level. Clearance of solid materials is an issue that has significant economic consequences for decommissioning projects where large quantities of such materials are generated. The cost of treating these materials as low-level radioactive waste (LLW) is prohibitive. A regulatory mechanism could remove economic burdens on such projects while maintaining the public health and safety standards. At the federal level major initiatives are being undertaken by the U.S. Nuclear Regulatory Commission (NRC) and the U.S. Department of Energy (DOE). The U.S. Environmental Protection Agency (EPA) has also taken some steps in this area under their Clean Materials Program. In the private sector, the nuclear industry is active through the Nuclear Energy Institute (NEI). The Health Physics Society (HPS) prepared the ANSI/HPS N13.12 standard about four years ago, which has been approved by the American National Standards Institute (ANSI). The American Nuclear Society (ANS) has recently released a Position Statement on the clearance of licensed materials from nuclear sites and the Society has been active in the national deliberations on this subject. The National Academies (NA) conducted a study for the NRC on alternatives for controlling the release of solid materials and their report was issued in 2002. The steel and concrete industries have also participated in the NRC rulemaking process and are opposed to any release standards for materials that may have residual radioactivity on them. This was clear from industry representatives at the stakeholder workshops conducted by the NRC as a part of the enhanced rulemaking effort. A review of all these initiatives shows the intensity of the debate but it also highlights the need for one national standard, preferably dose based, thus allowing site-specific application through derived radioactivity limits. Thus, interagency cooperation and agreement are necessary at the federal level. Consensus is necessary with standard writing organizations, professional societies, public and other stakeholders. This paper provides an overview of the developments in the United States in the area of clearance of solid materials, a brief comparison to international activities, and a discussion of key points for consensus building that is necessary for any initiative to succeed.

Opening and Operating the WIPP: A Regulator’s Perspective on Policy and Process

2001 ◽  
Author(s):  
Scott D. Monroe
Keyword(s):  
Radioactive Waste ◽  
Waste Disposal ◽  
Environmental Protection Agency ◽  
Department Of Energy ◽  
Radioactive Waste Disposal ◽  
Protection Agency ◽  
Waste Isolation Pilot Plant ◽  
Policy Issues ◽  
Disposal Facility ◽  
The U.S

Abstract The Waste Isolation Pilot Plant (WIPP) is the United State’s (U.S.) first deep disposal facility for transuranic radioactive (TRU) waste generated as a result of defense activities. The U.S. Environmental Protection Agency (USEPA or “the Agency”) initially certified the WIPP in May 1998, and WIPP received the first shipment of TRU waste on March 26, 1999. Every five years thereafter, USEPA is required by law to recertify whether the WIPP continues to comply with the USEPA’s radioactive waste disposal regulations. USEPA is coordinating with the U.S. Department of Energy (USDOE), which operates the WIPP, to prepare for the first recertification in 2004. This process involves many interesting technical and policy issues.

Post-Closure Removal of Long-Lived Radioactive Waste From a Deep Geological Repository in Bedded Salt

2001 ◽  
Author(s):  
Mark L. Matthews ◽  
Leif G. Eriksson
Keyword(s):  
Radioactive Waste ◽  
Rock Salt ◽  
Environmental Protection Agency ◽  
Department Of Energy ◽  
Feasibility Analysis ◽  
Legal Challenges ◽  
Geological Repository ◽  
Deep Geological Disposal ◽  
Waste Removal ◽  
The U.S

Abstract In recent years, retrievability (and various permutations of this term) has emerged around the world as a means to achieve and enhance public acceptance of deep geological disposal of long-lived radioactive wastes/materials (LLRMs). In this debate, it is often erroneously suggested that post-closure retrievability of the emplaced LLRMs cannot be accomplished in salt. In October 1996, the U.S. Department of Energy (DOE) submitted the Waste Isolation Pilot Plant (WIPP) Compliance Certification Application (CCA) to the U.S. Environmental Protection Agency (EPA) for review and approval. The CCA included a feasibility analysis defining a five-phased approach to post-closure waste removal from the WIPP rock salt repository based on currently available equipment and technologies. The feasibility analysis addressed highly adverse workers’ safety and waste retrieval conditions, including: 1. Radioactivity. 2. Hazardous constituents. 3. Gas. 4. Brine. 5. Rock integrity (instability). The concluding statement in the CCA was that “In no case, however, are the conditions expected to render removal impossible”. In May 1998, the EPA announced that WIPP complied with all applicable radioactive waste management and disposal regulations. This announcement was preceded by intense EPA and public scrutiny and oversight, which included successfully overcoming two legal challenges. Hence, the global application of the WIPP waste-removal feasibility analysis is: LLRM emplaced in a rock salt repository can be removed during the post-closure period with currently available technologies!

Micropollutants Produced by Disinfection of Wastewater Effluents*

1982 ◽  
Vol 14 (12) ◽  
pp. 45-59 ◽  
Author(s):  
R L Jolley ◽  
R B Cumming ◽  
N E Lee ◽  
J E Thompson ◽  
L R Lewis
Keyword(s):  
Wastewater Treatment ◽  
Uv Irradiation ◽  
Base Pair ◽  
Wastewater Treatment Plants ◽  
Department Of Energy ◽  
Union Carbide Corporation ◽  
Organic Constituents ◽  
Chemical Effects ◽  
Base Pair Substitution ◽  
The U.S

The principal objective of this research program was to examine the effects of disinfection by chlorine, ozone, and ultraviolet light (uv) irradiation on nonvolatile organic constituents relative to chemical effects and the formation of micropollutants. In a comparative study of highly concentrated samples of effluents from nine wastewater treatment plants, it was determined that disinfection with chlorine or ozone both destroys and produces nonvolatile organic constituents including mutagenic constituents. The chemical effects of disinfection by uv irradiation were relatively slight, although the mutagenic constituents in one effluent were eliminated by this treatment. The nine wastewater treatment plants were selected by using the following criteria: disinfection method, nature of wastewater source, type of wastewater treatment, standards for quality of treatment, and geographical location. The treatment plants varied from pilot plant and small plants [0.05 m3/s (1 Mgd)] treating principally domestic waste to large plants [4.4 m3/s (100 Mgd)] treating principally industrial waste. Four plants used only chlorine for disinfection, four used ozone for disinfection, and one used uv irradiation for disinfection. Eight treatment plants used conventional secondary or more advanced wastewater treatment, and one plant used primary treatment. The following methodology was used in this investigation: grab sample collection of 40-L samples of undisinfected and disinfected effluents; concentration of the effluents by lyophilization; high-pressure liquid chromatographic separation of nonvolatile organic constituents in effluent concentrates using uv absorbance, cerate oxidation, and fluorescence detectors; bacterial mutagenicity testing of concentrates and chromatographic fractions; and identification and characterization of nonvolatile organic constituents in mutagenic HPLC fractions. With these procedures, over 100 micropollutants were identified in the wastewater effluent concentrates. Interplant comparison revealed considerable variability in the presence of mutagenic nonvolatile organic constituents in the undisinfected effluent concentrates as well as much variability in the destruction of the mutagenic constituents and the formation of other mutagenic constituents as a result of disinfection. Moreover, the effects varied on samples collected at the same wastewater treatment plant at different periods. No micropollutants known to be mutagens were identified in the mutagenic HPLC fractions separated from the undisinfected, chlorinated, and ozonated effluent concentrates. The mutagenic activity of the nonvolatile organic constituents in one chlorinated effluent concentrate was not attributable to organic chloramines. Most of the mutagens detected in effluent concentrates are direct acting and do not require metabolic activation. Both base-pair substitution mutagens and frame-shift mutagens occurred in the wastewater concentrates, but the former type was more frequent. For many of the compounds in effluents, strain TA-1535 was more sensitive than strain TA-100 in detecting base-pair substitution mutagens. *Research sponsored by the U.S. Department of Energy and the U.S. Environmental Protection Agency. The work was carried out at the Oak Ridge National Laboratory, which is operated by the U.S. Department of Energy under contract W-7405-eng-26 with the Union Carbide Corporation.

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