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A new approach for teaching general chemistry that combines lecture and laboratory into one seamless session and incorporates instructional methods supported by research-based findings is described. A comparative study of the understanding of basic chemical concepts and effective use of high-order cognitive skills by students exposed to two different instructional formats is done and the results presented.

Storm-water experts agree that the currently used best management practice (BMP) percent removal methodology metric has many flaws, and some have suggested using a BMP effluent concentration metric. This case study examines establishing an effluent target concentration for BMPs that relates to the health of macroinvertebrates in the receiving water. In North Carolina, 193 ambient water quality monitoring stations were paired with benthic macroinvertebrate health ratings collected in very close proximity. Water quality for the sites ranged from excellent to poor and was divided into three distinct ecoregions: Mountain, Piedmont, and Coastal. Statistically significant relationships were found in one or more ecoregions for dissolved oxygen, fecal coliform, N[H.sub.3], N[O.sub.2-3]-N, total Kjeldahl nitrogen, total nitrogen (TN), and total phosphorus (TP). BMPs can then be selected and designed to meet these target effluent concentrations. Based upon this research, a development, and therefore set of BMPs, in Piedmont North Carolina could be required to release TN and TP effluent concentrations of 0.99 mg/L and 0.11 mg/L, respectively. These concentrations are both associated with 'good' benthos health. The new method was most effective in the Piedmont ecoregion, however with more data collection, the Mountain and Coastal ecoregions may also benefit. DOI: 10.1061/(ASCE)EE.1943-7870.0000185 CE Database subject headings: Stormwater management; Water quality; Best Management Practice; Regulations. Author keywords: Storm water; Benthic macroinvertebrates; Water quality; BMPs; Regulatory standards.

A study was conducted in western North Carolina, along the southeastern extent of the U.S. trout populations, to examine the effect of bioretention areas on runoff temperature. Four bioretention areas were monitored during the summers of 2006 and 2007. It was found that smaller bioretention areas, with respect to the size of their contributing watershed, were able to significantly reduce both maximum and median water temperatures between the inlet and outlet. The proportionately larger bioretention areas were only able to significantly reduce maximum water temperatures between the inlet and outlet; however, these systems showed evidence of substantial reductions in outflow quantity, effectively reducing the thermal impact. Despite temperature reductions, effluent temperatures still posed a potential threat to coldwater streams during the peak summer months. During the summer months, effluent temperatures were generally coolest at the greatest soil depths, supporting evidence of an optimum drain depth between 90 and 120 cm. The ability of bioretention areas to reduce storm-water temperature and flows supports their application to reduce the thermal impacts of urban storm-water runoff. DOI: 10.1061/(ASCE)EE. 1943-7870.0000022 CE Database subject headings: Stormwater management; Temperature; Aquatic habitats; Runoff; Ecology; Infiltration; Urban development.

Two grassed bioretention cells including internal storage zones (ISZs) were monitored for 16 months in central North Carolina. Each cell had a surface area of 106 [m.sup.2] and fill media depths were 0.75 and 1.05 m for the north (North) and the south (South) cells, respectively. Asphalt parking lot inflow and outflows were analyzed for nitrogen and phosphorus forms and fecal coliform (FC). Outflow volumes and peak flows for individual storms were generally less than those of inflow. Overall, except for N[O.sub.2.3]-N, effluent nitrogen species event mean concentrations (EMCs) and loads were significantly ([alpha]=0.05) lower than those of the inflow, and nitrogen species load reductions ranged from 47 to 88%. Apart from fall and winter, during which a longer hydraulic contact time seemed to be needed, the ISZs appeared to improve denitrification. Total phosphorus (TP) and [OPO.sub.4]-P EMCs were significantly lower than those of the inlet. Reductions were 58% (South) and 63% (North) for TP and 78% (North) and 74% (South) for [OPO.sub.4]-P. There was no significant difference in TP and [OPO.sub.4]-P loads between the inlet and the two outlets. Moreover, effluent concentrations for both phosphorus species were low, relative to other studies. The best nutrient EMC and load reductions occurred during the warm and humid seasons. When considering effluent concentrations in addition to removal rates, the grassed cells showed promising results for FC and nutrient pollution abatement when compared to conventionally vegetated bioretention (trees, shrubs, and mulch) previously studied in North Carolina. DOI: 10.1061/(ASCE)IR.1943-4774.0000006 CE Database subject headings: Stormwater management; Runoff; Water pollution; Sustainable development; Vegetation; Nutrients; North Carolina; Inflow.

Bioretention, or variations such as bioinfiltration and rain gardens, has become one of the most frequently used storm-water management tools in urbanized watersheds. Incorporating both filtration and infiltration, initial research into bioretention has shown that these facilities substantially reduce runoff volumes and peak flows. Low impact development, which has a goal of modifying postdevelopment hydrology to more closely mimic that of predevelopment, is a driver for the use of bioretention in many parts of the country. Research over the past decade has shown that bioretention effluent loads are low for suspended solids, nutrients, hydrocarbons, and heavy metals. Pollutant removal mechanisms include filtration, adsorption, and possibly biological treatment. Limited research suggests that bioretention can effectively manage other pollutants, such as pathogenic bacteria and thermal pollution, as well. Reductions in pollutant load result from the combination of concentration reduction and runoff volume attenuation, linking water quality and hydrologic performance. Nonetheless, many design questions persist for this practice, such as maximum pooling bowl depth, minimum fill media depth, fill media composition and configuration, underdrain configuration, pretreatment options, and vegetation selection. Moreover, the exact nature and impact of bioretention maintenance is still evolving, which will dictate long-term performance and life-cycle costs. Bioretention usage will grow as design guidance matures as a result of continued research and application. DOI: 10.1061/(ASCE)0733-9372(2009)135:3(109) CE Database subject headings: Sustainable development; Filtration; Biological treatment; Hydrology; Water quality; Stormwater management; Best management practice.

The surface infiltration rates of 40 permeable pavement sites were tested in North Carolina, Maryland, Virginia, and Delaware. Two surface infiltration tests (pre- and postmaintenance) were performed on 15 concrete grid paver lots filled with sand. Maintenance was simulated by removing the top layer of residual material (13-19 mm). Simulated maintenance significantly (p DOI: 10.1061(ASCE)0733-9437(2007) 133:3(249) CE Database subject headings: Permeable pavement: Permeable concrete: Permeable block pavers: Urban stormwater; Runoff; Surface infiltration; Best management practice.