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1.
Dormant-season application of biosolids increases desert grass production more than growing season application in the first growing season after application. Differential patterns of NO3-N (plant available N) release following seasonal biosolids application may explain this response. Experiments were conducted to determine soil nitrate nitrogen dynamics following application of biosolids during two seasons in a tobosagrass [Hilaria mutica (Buckl.) Benth.] Chihuahuan Desert grassland. Biosolids were applied either in the dormant (early April) or growing (early July) season at 0, 18, or 34 dry Mg ha(-1). A polyester-nylon mulch was also applied to serve as a control that approximated the same physical effects on the soil surface as the biosolids but without any chemical effects. Supplemental irrigation was applied to half of the plots. Soil NO3-N was measured at two depths (0-5 and 5-15 cm) underneath biosolids (or mulch) and in interspace positions relative to surface location of biosolids (or mulch). Dormant-season biosolids application significantly increased soil NO3-N during the first growing season, and also increased soil NO3-N throughout the first growing season compared to growing-season biosolids application in a year of higher-than-average spring precipitation. In a year of lower-than-average spring precipitation, season of application did not affect soil NO3-N. Soil NO3-N was higher at both biosolids rates for both seasons of application than in the control treatment. Biosolids increased soil NO3-N compared to the inert mulch. Irrigation did not significantly affect soil NO3-N. Soil NO3-N was not significantly different underneath biosolids and in interspace positions. Surface soil NO3-N was higher during the first year of biosolids application, and subsurface soil NO3-N increased during the second year. Results showed that biosolids rate and season of application affected soil NO3-N measured during the growing season. Under dry spring-normal summer precipitation conditions, season of application did not affect soil NO3-N; in contrast, dormant season application increased soil NO3-N more than growing season application under wet spring-dry summer conditions.  相似文献   
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For both private corporations and military branches, downsizing and consolidation are becoming more commonplace. A range of environmental concerns must be addressed to effectively implement a consolidation program. A facility deactivation program can often become a minefield for an organization. Responsible personnel are typically inexperienced with the process, and this can lead to costly mistakes. This article provides insight into this topic based on experience gained with a multifacility program and related environmental issues. It emphasizes the importance of detailed, up-front, proactive project planning; a solid program management system; and accurate identification of project objectives and deliverables.  相似文献   
4.
This study presents the results of a laboratory investigation conducted to evaluate the efficiency of coal fly ash to control the formation of acid mine drainage (AMD) from mine waste. Site-specific materials, coal fly ash from Atikokan Thermal Generating Station and mine tailings from Musselwhite mine, were mixed at different proportions for the investigation of the drainage chemistry and the optimal mix using static testing (acid–base accounting) and kinetic (column) testing. The acid–base accounting (ABA) results indicated that the fly ash possessed strong alkaline (neutralization) potential (NP) and could be used in the management of reactive mine tailings, thus ensuring prevention of AMD in the long-term. Column tests conducted in the laboratory to further investigate long-term performance of fly ash in the neutralization and prevention of acid mine drainage from tailings similarly showed that mixing fly ash with mine tailings reduces dissolution of many heavy metals from tailings by providing alkalinity to the system. It was found that a fly ash to tailings mass ratio equal to or greater than 15% can effectively prevent AMD generation from Musselwhite mine tailings in the co-placement approach.  相似文献   
5.
Book Reviews     
ION‐SELECTIVE ELECTRODES IN ANALYTICAL CHEMISTRY, Vol. 2 by H. Freiser (ed.), Plenum Press, New York, 1980.

CARCINOGENESIS AND MUTAGENESIS by Myron A. Mehlman, Morris F. Cranmer and Raymond E. Shapiro, from the Journal of Environmental Pathology and Toxicology (Official Organ of the American College of Toxicology), 388 pages and 135 tables and figures, 1977, linen, format 261 × 178 mm, ISBN 0–930376–02–1, printed by Pathotox Publishers, Inc., Park Forest South, Illinois 60466, $23.00.  相似文献   
6.
RECOMMENDED HEALTH‐BASED LIMITS IN OCCUPATIONAL EXPOSURE TO HEAVY METALS, Technical WHO‐Report 647 of a WHO Study Group (Chairman: Professor R. L. Zielhuis, University of Amsterdam) in English, French and Spanish, 1980, 116 pages, no index, many valuable literature references added to each chapter, stiff paper cover, format 200 × 140 mm, ISBN 92–4–120647–0, WHO—Health &; Biomedical Information Programme, CH‐1211 Geneva 27, SFr. 8‐

POLYCYCLIC AROMATIC HYDROCARBONS IN THE AQUATIC ENVIRONMENT: SOURCES, FATES AND BIOLOGICAL EFFECTS, Dr. Jerry M. Neff, Texas A &; M University, College Station, Texas, U.S.A., 262 pages (including a bibliography with literature references of 27 pages, a glossary of abbreviations of two pages and an index of 4 pages), 30 figures, 89 tables, linen, format 230 × 148 mm, ISBN 0–85334–832–4, Elsevier's Applied Science Publishers Ltd., Barking, Essex IG11 OSA, England 1979, £22.50.

EVALUATION OF THE CARCINOGENIC RISK OF CHEMICALS TO HUMANS: SOME METALS AND METALLIC COMPOUNDS, World Health Organization/International Agency for Research on Cancer, IARC Monograph, Volume 23, Lyon 1980, 438 pages (including a preamble and general remarks of 26 pages and a cumulative index for volumes 1–23 (only 4 references related to volume 23) of 20 pages), 36 tables, many valuable literature references added to each chapter, stiff paper cover, format 240 × 180 mm, ISBN 92–832–1223–1, WHO—Health &; Biomedical Information Programme, CH‐1211 Geneva 27, US $30.‐ or SFr. 50.‐  相似文献   
7.
Simultaneous measurements of individual hydrocarbons and individual carbonyls were carried out at a downtown Los Angeles location. Concentrations are presented for 50 compounds in morning air samples. While paraffins (C ≥ 4) were a major hydrocarbon subclass on a ppmC basis, higher aromatics (C ≥ 8) were the major component when taking reactivity considerations into account. Comparison of the results with emission inventory data showed good agreement for many hydrocarbons and for paraffins as a subclass. Measured olefins and aromatics concentrations were substantially lower and higher, respectively, than those expected from inventory data.  相似文献   
8.
ABSTRACT: In a study to measure the efficacy of chioramines at inactivating Giardia cysts, the ability of cysts to excyst was measured after exposure to different concentrations of chloramines, for different times, and at different temperatures and pH. The chloramines were generated by mixing ammonium sulfate and sodium hypochlorate in water to approximate a 7:1 chlorine:ammonia ratio by weight. Times of 40, 80, 180, and 270 minutes; temperatures of 3, 10, and 18°C; target chioramine concentrations of 0.4, 1.4, 2.0, and 2.6 mg/L; and pH of 7.0 and 8.5 were the actual values tested. The combinations of these variables that were able to inactivate >99.8 percent of the cysts were a minimum chloramine concentration of 2.26 mg/L applied for 270 minutes at a water temperature of 10°C; and at 18°C, averaged minimum chloramine concentrations of 2.14 and 1.55 mg/L applied for 180 and 270 minutes, respectively. The minimum CT values corresponding to these combinations capable of >99.8 percent cyst inactivation, are 610 at 10°C and 385 at 18°C. Temperature was noted to exert a major effect on the ability of chloramines to inactivate cysts. Modifications of the methods used to generate chloramines may have an effect on the capacity of this disinfectant to inactivate cysts.  相似文献   
9.
ABSTRACT: Texas is one of the states in which limitations in water supplies could severely constrain economic growth in certain areas. The traditional planning approach for addressing this problem has involved devising schemes for large water development projects, which for many years included the importation of water from other states. Now the attitude towards water resource management is changing, and it is generally agreed that better management of existing supplies is the preferred approach. In this paper we review some of the changes that have recently occurred in Texas, including attempts to streamline the water institutions in such a way that they might be more responsive to the need for more comprehensive management of water resources statewide, with greater emphasis on social and environmental concerns.  相似文献   
10.
Setback regulations-legislated distances that livestock production facilities must be removed from surrounding properties-are meant to mitigate odor impacts. If the setback length is too short, then there is evidence that surrounding properties and people suffer uncompensated damages. If, on the other hand, setback lengths are too long, then livestock producers may be paying more than that required to compensate for odor-related environmental damages. The purpose of this study is to assess the impact of Kentucky's livestock production facility setbacks on the value of surrounding properties and farm financial management decisions. This paper develops a model of the benefits of livestock odor reduction and the livestock odor abatement cost associated with setback lengths paid by producers. The results of this investigation indicate that the mandated setback lengths for Kentucky are too short. Livestock production firms are worse off under longer setback lengths, but the losses to surrounding home owners far exceed the firm gains at the mandated setbacks. A finding of this study is that the firm has no incentive to completely protect the legislated setback length. Livestock producers in compliance with the relevant setback length may feel protected from odor lawsuits despite damage being done to surrounding property. This suggests that the perceived threat of lawsuit is currently low in the state of Kentucky. Both industry and public goals could be met from further research including location and economic impact of livestock production.  相似文献   
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