A Profile and Management of the US Army's underground storage tanks

The US Army owns more than 10,000 underground storage tanks (USTs), many of which are old and may be leaking. The Resource Conservation and Recovery Act of 1976 required tank owners to collect and report data on them by May 1986. In order to manage the large amounts of information on its USTs, the Army developed a microcomputer-based data base system. The data base system is user friendly and allows the user to store, organize, and manipulate the UST data. A leak potential index (LPI) was also developed and calculated for each of the Army's USTs. The LPI is used to prioritize USTs so that those with higher LPIs can be monitored closely. A characteristic profile of Army USTs according to construction material, capacity, age, content, and LPI is presented in this paper.The opinions expressed in this paper are those of the authors and do not necessarily reflect the views of the US Department of the Army, nor does the mention of trade names or commercial products constitute endorsement or recommendation for use.     

基于自回归GA-BP神经网络的AQI预测

基于徐州市2013年12月—2018年11月的空气质量指数日均值,建立了时间序列自回归输入的GA-BP神经网络模型用于空气质量指数预测。结果表明,所建立的网络模型能够准确预测徐州市空气质量指数的变化趋势,其中夏季预测相对误差18. 23%,仿真均方根误差(RMSE)为14. 59;冬季预测相对误差9. 14%,仿真RMSE为11. 47。     

废水中有机污染指标监测方法的选择

综合考察了废水中各种有机污染物综合指标的测试对象、干扰、准确度、精确度及其分析测试技术等各种因素 ,对实现其自动化连续测量的影响。针对某些监测技术产生的严重二次污染问题 ,提出了绿色 (清洁 )监测技术的概念。文章认为在重点废水污染源安装在线监测系统实行总量控制的过程中 ,应避免使用造成严重二次污染的 CODCr在线监测仪 ,而应当采用臭氧氧化法在线监测仪 ,或其他综合指标 ,如 TOC     

Automated Classification of an Environmental Sensitivity Index

Environmental Sensitivity Indices (ESI) composed of many field-data are essential for monitoring and control systems. At the beginning of the last decade an ESI of the German Wadden Sea was developed for use by the relevant authorities. This ESI was derived by experts semi-manually analysing the extensive field data-set. An algorithm is presented here which emulates human expert-decisions on the classification of sensitivity classes. This will permit the necessary regular updates of ESI-determination when new field data become available using automated classifications procedures. After tuning the algorithm parameters it generates decisions identical to those of human experts in about 97% of all locations tested. In addition, the algorithm presented also enables erroneous or extremely seldom field data to be identified.     

The water quality of the Vrgorska Matica River

The article presents the results of investigations carried out on the 42 km long Vrgorska Matica River, which flows through the 15 km long Vrgorsko polje (polje = field) which covers an areaof 3000 ha, and is at 24 m a.s.l., located in Southern Croatia.It covers the years 1997–2000 after this field had been reclaimed for agricultural use.The purpose of the investigations was to evaluate the influence of the Vrgorska Matica River which is part of the catchment areaof the Trebizat River, on the water quality in Modro Oko Lakeand Prud Spring, which are used for water supply and are locateddownstream of the Vrgorska Matica River on the right bank of theNeretva River.The water quality was evaluated by using the quality index basedon the following nine parameters: temperature, mineralization, corrosion coefficient, K = (Cl + SO₄)/HCO₃, dissolvedoxygen, BOD₅, total N, protein N, total phosphorus and totalcoliform bacteria (100 mL)^-1 (MPN coli (100 mL)^-1) for which concentrations C ₉₅ are calculated. After completingthe nine parameters the results of C ₉₅ were recorded andtransferred to the score table to obtain the q-value. The q-value used is an attempt to quantify environmental factors which would otherwise be qualitative. For each parameter the q-value was multiplied by a weighting factor based upon the relative significance of the parameter. The nine resulting scores values were then added to arrive at an overall water quality index (S₉₅).According to this index the water can be classified into four categories. The first category, according to the Croatian Water Classification Act (Official Bulletin No. 77,1998), includes ground and surface waters used for drinking or in the food industry either in its natural state or after disinfection, and surface water used for raising high-quality species of fish, ranging from 85–100 scores; the second category includes waterused in its natural state for swimming and recreation, sports orfor other species of fish and the treated water used for drinkingand other industrial purposes ranging between 70–85 scores. Thethird category includes water used in industry with no specific requests upon water quality and in agriculture ranging from 50–70 scores; the fourth category includes water used only afterbeing treated in areas with water shortage which is less than 50 scores.According to results obtained by investigations, the water of theVrgorska Matica River and Prud Spring falls into the second (II)category, while water from the Modro Oko Lake belongs to the first (I) category. This means that the Matica River water does not influence the water quality of the Modro Oko Lake. This lakewater quality is influenced by the Rastoka Matica River from theRastoko polje which is located upstream from the Vrgorska MaticaRiver. This has been proved by dyeing tests.     

沉积物重金属污染评价——以巢湖龟山区为例

文章系统介绍了水环境沉积物重金属污染评价方法,比较了不同评价方法的优缺点。采用地累积指数法和潜在生态风险法对巢湖龟山区沉积物中Pb、Cu、Zn、Cr等4种重金属污染进行了评价。结果表明,巢湖龟山区沉积物中金属Cr有中度生态风险,Cu有轻度污染,Pb和Zn没有污染。结果也说明,对沉积物中重金属污染的评价需要用多种方法进行比较评价。     

加盐法测定高锰酸钾指数

探讨了在碱性条件下，加入氯化钙能提高高锰酸钾对有机物的氧化率，从而得到比常法高的高锰酸钾指数，能真实地反映水体受污染的情况。     

The Quality of Water in the Buško Blato Reservoir

The article presents the results of chemical andmicrobiological measurements of the water quality in theBuko Blato reservoir, the largest in Europe, in the period 1989 to 1998.The aim was to observe possiblechanges in water quality during the past decade and itsinfluence on the downstream section of the Cetina River andits numerous tributaries and reservoirs, where there are twolarge regional water supply systems. This reservoir wasbuilt in order to exploit the high hydro-electric potentialof small streamflows in the karst fields of south-westernBosnia. It has strongly influenced the hydrologicconditions of the downstream section of the Cetina River.Buko Blato is a relatively shallow reservoir with the meandepth of 5 m. It covers an area of 57 km². The waterexchange in the reservoir is slow, occurring from one toseveral years. When the water inflow exceeds the hydroelectric plant demands the excess water is delivered by a reversible channel and pre-pumped into the Buko Blato reservoir. The total and carbonate water hardness in thereservoir is lower than in the Cetina River and in typicalkarst streamflows, since the water in this reservoir comesmainly from surface sources including numerous springs withhigh capacity oscillations, torrents and rainfall.Measurements, carried out during the past years, showed asignificant increase in nitrate content as well as in thecoli bacteria and a less significant increase in totalphosphorus content. The water quality was evaluated asmezotrophic according to the total phosphorus content basedon the Carlson index of trophic level, a lower quality thanin the Perua reservoir, upstream on the Cetina River. Thelatter contains a smaller phosphorus content and wasclassed between oligotrophic and mezotrophic. According tothese data, employing the Vollenweider equation, the totalphosphorus content in this water should not exceed the meanof 20 mg m^-3 P. The results indicate that the water inthe Buko Blato reservoir did not deteriorate the waterquality on the downstream section of the Cetina River.     

Ozone Indicators Determined at Rural Sites in the Eastern United States by two Monitoring Networks

Ozone levels at Clean Air Status andTrends Network (CASTNet) and nearby rurally-designatedState and Local Air Monitoring Stations (SLAMS) siteslocated in the eastern United States (U.S.) arecompared using daily indicators (i.e., maximum, range,and SUM06) based on hourly O₃ measurements. Comparisons are also made using monthly and summertimethree-month SUM06 determinations aggregated from dailydata. Comparison of O₃ indicators at the pairedCASTNet-SLAMS sites generally shows better agreementfor O₃ maximum than for range or SUM06. Thehighest correlation of daily O₃ indicators occursfor paired sites that are separated by less than 100miles, and the correlation diminishes with increasingseparation distance. Correlation coefficients exceed0.70 in 49% of the comparisons of maximum, in23% of range comparisons and in 5% ofSUM06 comparisons, suggesting that substitution ofSLAMS for CASTNet O₃ measurements would fail tocapture a substantial amount of the variability inO₃ indicators present at the CASTNet sites. Correlations of O₃ indicators at CASTNet andpaired nearby SLAMS sites are 0.80 in a relativelysmall number of cases. Despite the high correlationin even these cases, O₃ behavior at paired sitesis not identical and shows systematic differences thatare reflected in the O₃ minimum, hourly averageconcentrations, and the monthly and three-month SUM06. Ozone measurements at nearby rurally-designated SLAMSsites may not capture the `rural' nature of the airquality being monitored at CASTNet sites and, in mostcases, may not be sufficiently representative of theconcentration at CASTNet sites to permit O₃measurements at SLAMS sites to be used in lieu ofmeasurements at CASTNet sites. As a result, if ruralO₃ concentration data are needed, then O₃monitoring at carefully chosen, rurally representativesites is recommended.     

关于模糊综合指数与模糊向量加权记分

通过将模糊向量加权记分与模糊综合指数的计算步骤、计算内容和方法一一进行比较,证明模糊向量加权记分与模糊综合指数无本质差异。所采用的分制规定差异,只能使模糊向量加权记分所得结果更加不合理。采用模糊综合指数法,选用恰当的权重,可以克服“优劣倒置”现象。