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Honolulu, HI, United States

Liu C.C.,University of Hawaii at Manoa | Dai J.J.,City and County of Honolulu
Journal of the American Water Resources Association | Year: 2012

Basal aquifers, in which freshwater floats on top of saltwater, are the major freshwater supply for the Hawaiian Islands, as well as many other coastal regions around the world. Under unexploited or natural conditions, freshwater and the underlying seawater are separated by a relatively sharp interface located below mean sea level at a depth of about 40 times the hydraulic head. With forced draft, the hydraulic head of a basal aquifer would decline and the sharp interface would move up. It is a serious problem of seawater intrusion as huge amounts of freshwater storage is replaced by saltwater. Also, with forced draft, the sharp interface is replaced by a transition zone in which the salinity increases downward from freshwater to saltwater. As pumping continues, the transition zone expands. The desirable source-water salinity in Hawaii is about 2% of the seawater salinity. Therefore, the transition zone expansion is another serious problem of seawater intrusion. In this study, a robust analytical groundwater flow and salinity transport model (RAM2) was developed. RAM2 has a simple mathematical structure and its model parameters can be determined satisfactorily with the available field monitoring data. The usefulness of RAM2 as a viable management tool for coastal ground water management is demonstrated by applying it to determine the sustainable yield of the Pearl Harbor aquifer, a principal water supply source in Hawaii. © 2012 American Water Resources Association.

Kobayashi M.,City and County of Honolulu | Kobayashi M.,University of Hawaii at Manoa | Cohle S.D.,Laboratory Medicine
Cardiovascular Pathology | Year: 2016

Background Eosinophilic coronary periarteritis (ECPA) is a rare disease found in cases of sudden cardiac death due to coronary vasospasm or spontaneous coronary artery dissection. Currently, the etiology, pathogenesis, and pathophysiology of ECPA are unknown. Cases of ECPA with a history of allergic disorders are rare. Only one case of ECPA with tissue eosinophilia in another organ has been reported. Methods A 50-year-old male suddenly died after complaining of chest pain. An autopsy with histopathologic analysis was performed. Results A short segment of the left anterior descending artery had ECPA with dense eosinophilic inflammation of the adventitia and mild atherosclerosis. There were findings atypical of ECPA including mild focal eosinophilic infiltration of the intima and media associated with proliferation of vasa vasorum, fragmented internal and external elastic laminae, and fibrosis of the media. In addition, eosinophilic inflammation of the esophagus without mucosal involvement was present. The eosinophilic inflammation of the coronary artery and esophagus was accompanied by an increased number of mast cells. Conclusions This case suggests that ECPA and atherosclerosis may act synergistically by induction of inflammation and vasa vasorum neovascularization. Vasa vasorum and mast cell infiltration may trigger vasospasm and spontaneous coronary artery dissection. Although concurrent tissue eosinophilia elsewhere is rarely observed in cases of ECPA, collective analysis of these cases may elucidate the etiology and pathophysiology of ECPA. © 2015 Elsevier Inc.

Sadri A.,City and County of Honolulu | Barlaz M.A.,North Carolina State University | Hater G.R.,Waste Management Inc.
Waste Management and Research | Year: 2010

Laboratory-scale reactors containing mixtures of municipal solid waste and wastewater treatment biosolids were monitored to assess the effect of biosolids on refuse decomposition and on phosphorus (P) cycling and speciation among orthophosphate, acid-hydrolysable P, and organic P. The co-disposal of 10 to 20% (by wet weight) aerobically-digested biosolids with residential refuse was compatible with refuse decomposition although the biosolids did not increase either the maximum methane production rate or the cumulative yield, and did not reduce lag times to the onset of methane production. The results of this study indicated that dissolved reactive phosphorus (DRP) was the dominant dissolved P fraction throughout refuse decomposition and that it was negatively correlated with the methane production rate and pH (r2 = 0.35 for both). P was not found to limit methane production. Biosolids increased dissolved P as well as ammonia-N in some reactors, but this did not have a significant impact on maximum methane production rates. The maximum tolerated Na+ and K+ concentrations during active methane production were at least 4100 mg Na+ L-1 and 800 mg K+ L-1, respectively. © The Author (s), 2010.

Sadri A.,City and County of Honolulu | Staley B.F.,North Carolina State University | Barlaz M.A.,North Carolina State University | Xu F.,North Carolina State University | Hater G.R.,Waste Management Inc.
Waste Management | Year: 2010

Non-hazardous industrial process wastes are receiving increased interest from landfill owners, especially with respect to bioreactor operation. These wastes could benefit bioreactors as they represent sources of liquid, nutrients, and/or substrate as well as revenue. However, landfill operators should exercise caution in accepting these wastes, as some could have detrimental effects on refuse decomposition. In this research, the use of laboratory-scale tests to evaluate the effect of one such waste on refuse decomposition is demonstrated. The waste evaluated, referred to as burnt sugar, is an acidic byproduct of corn-based polylactic acid production and represents a source of readily-biodegradable carbon. Lactic acid was the primary constituent of the BS at 0.73 g/g and the COD was measured at 1230 mg COD/g. Testing protocols were adapted to address the specific concerns surrounding the material. Abiotic dissolution tests conducted at mesophilic temperatures indicated that the majority of the waste dissolved into leachate recirculated over a layer of the waste within several days. Abiotic mixing tests suggested that the waste would acidify refuse to pH 6.41 at a loading of 21.9 g/dry kg refuse. However, in biologically active tests, the refuse was able to convert loadings as high as 196.7 g/dry kg refuse to methane. As the loadings increased toward and beyond this level, pronounced detrimental effects to the refuse ecosystem were observed, including a decrease in pH, accumulation of volatile fatty acids and COD, and lag in methane production. The results suggested that actively decomposing refuse has the potential to attenuate relatively high loading of a rapidly degradable but acidic substrate. Nonetheless, caution in the implementation of a field program to accept rapidly biodegradable acidic wastes is critical. © 2009.

Gesell G.H.,HDR | Langham S.,City and County of Honolulu | Margolis R.L.,Covanta Energy Corporation | Nelson J.R.,HDR | Miller J.R.,HDR
19th Annual North American Waste-to-Energy Conference, NAWTEC19 | Year: 2011

The City and County of Honolulu on the Island of Oahu in the Hawaiian chain has been taking steps to reduce the need for landfilling and to continue to be self-sufficient for waste disposal. For an island, having the capacity to process all of its waste is crucial and producing power helps reduce reliance on imported fossil fuels. The City and County relies upon its waste-to-energy facility to manage the waste stream. The existing H-POWER Waste-to-Energy (WTE) Facility, which has been in operation for about twenty years, is a 2,000 ton-perday (tpd) refuse derived fuel (RDF) two-unit plant with a single condensing steam turbine generator. Recent actions to enhance and expand the H-POWER Facility have been undertaken to ensure the needs to the island will be met for the foreseeable future. Enhancements and an expansion of the existing H-POWER Facility have begun and are well into construction. The enhancements will improve environmental performance and reliability and the expansion will add nearly fifty percent to the facility capacity. When complete, the expanded facility will have a number of unique features that will improve its ability to manage more types of municipal solid waste. The facility expansion will utilize mass burn technology in a single 900 tpd combustion unit with an associated turbine generator. The expansion unit will feature fabric filters for particulate control and state-of-the-art Covanta Very Low NOx (VLNTM) technology intended to reduce NOx emissions well below that achieved with conventional selective non-catalytic reduction (SNCR) used at many other WTE plants in the USA. Independent of the expansion, the existing facility has been retrofitted with new fabric filters and induced-draft fans, which offer greater particulate and heavy metal control and improve control of other emissions. The existing facility is also getting much-needed improvements to boost reliability for many years to come. When the expansion comes on line, the facility will reliably generate about 7 percent of the island's electrical power as opposed to 5 percent from the current 2,000 tpd of waste processed. This paper explores progress to date on the revitalization of the H-POWER Facility and its expansion. © 2011 by ASME.

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