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Highway stormwater runoff was monitored at three highway sites in Los Angeles, California, during the 2000 to 2003 wet seasons. Event mean concentrations (EMCs), partial event mean concentrations (PEMCs), and mass first flush (MFF) factors were calculated for more than 20 water quality parameters for samples from 20 storm events from each site. The early runoff had higher concentrations, as indicated by the PEMCs at 30 and 60 minutes into the storm, which were 1.9 to 7.4 times higher than the EMCs. A strong first flush was observed for chemical oxygen demand (COD) and other organic pollutants, with 40% of the pollutant mass being discharged in the first 20% of the runoff. A weak first flush was observed for ionic pollutants, such as nitrate and nitrite. Pearson correlation analyses of the EMCs, PEMCs, and MFFs showed strong correlations among dissolved organic carbon, COD, total Kjeldahl nitrogen, oil and grease, and ammonia-nitrogen. Contrary to generally held beliefs, poor correlation between total suspended solids and most other conventional pollutants was observed. In addition, poor correlation between most monitored pollutants and storm characteristics, except for antecedent dry days, was observed. Water Environ. Res., 78, 2377Res., 78, (2006.

Stormwater runoff from highway land use is a common non-point source of pollutants. A large quantity of highway stormwater runoff characteristics were collected in California during the past three years. Correlations among various water quality parameters and constituents were performed using data sets collected over the 2000-2001, 2001-2002, and 2002-2003 wet seasons for 18, 21 and 23 storm events at three highway sites in west Los Angeles, California. In addition, statistical and graphical correlation analysis of the mass first flush ratio (MFF) with storm characteristics was made to determine if the first flush is related to site or storm characteristics. The results and analyses performed indicate that (1) TSS correlates well with most particulate-bound metals. However, TSS was poorly correlated with most other pollutants. (2) Strong correlations were also observed among dissolved and total metals; DOC, COD, TKN and oil and grease; conductivity and Cl. (3) Total metals, COD and DOC were generally well correlated with mass first flush, suggesting that BMPs that treat the early portion of runoff have an opportunity to remove high concentrations of these pollutants.

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Produtos derivados de ácidos húmicos têm bom mercado; entretanto, estes não são populares nessa região, devido ao alto custo imposto aos produtos importados. Por esta razão, é essencial identificar uma fonte nativa de ácidos húmicos como condicionador de solo. Carvões de baixa classe são encontrados em abundância em Mukah, com aplicação não energética largamente explorada. Estudos preliminares mostraram que o tratamento químico com ácido nítrico poderia aumentar potencialmente o rendimento essencial de ácidos húmicos de 20 a 85%. Entretanto, ácido nítrico é um item caro, o que pode aumentar o custo, portando a possibilidade de empregar outros oxidantes precisa ser avaliada. Neste estudo, os ácidos húmicos foram extraídos de carvão de baixa classe de Mukah, com oxidação usando HNO 3 , H 2 O 2 e KMnO 4 e foram comparados em termos de rendimento, características químicas e espectroscópicas. Os resultados indicaram que a oxidação com H 2 O 2 envolveu considerável perda de peso, sendo desfavorável para a produção de ácidos húmicos. A oxidação com permanganato de potássio não é recomendada, pois uma quantidade substancial de compostos inorgânicos foi introduzida aos produtos e o rendimento essencial obtido foi baixo. A oxidação com ácido nítrico continua sendo a escolha no processo de extração de ácidos húmicos, uma vez que a perda de massa envolvida foi aceitável; o rendimento de ácidos húmicos obtido foi alto com características de baixo teor de cinzas e alto teor de grupos funcionais ácidos. Humic acid-based products are well marketed; nevertheless, these products remain unpopular in this region possibly due to the higher selling price resulted from the cost imposed on the imported products. For this reason, it is essential to identify the indigenous source of humic acids as the soil conditioner. Abundant of low rank coals are found in Mukah and the non-energy application of the source are largely unexplored. Preliminary study reported that chemical treatment with nitric acid could potentially increase the essential yield of humic acids from 20% to 85%. Nitric acid is an expensive item, which could add on to the cost, hence possibility of employing other oxidative approaches need to be evaluated. In this study, the humic acids were extracted from the low rank coal of Mukah with HNO 3 , H2O 2 and KMnO 4 oxidation and were compared in terms of yield, chemical and spectroscopical characteristics. Results indicated that H 2 O 2 oxidation involved considerable weight losses upon oxidation render it unfavorable for production of humic acids. Potassium permanganate oxidation however was not recommended, as a substantial amount of inorganic compounds was introduced to the products and the essential yield generated was low. Nitric acid oxidation remains the choice of the process for extraction of humic acids as the weight losses involved was acceptable; the yield of humic acids obtained was high with characteristics of low ash content and high acidic functional groups.