Thomas P. Ballestero

Water Quality and Hydrologic Performance of a Porous Asphalt Pavement as a Storm-Water Treatment Strategy in a Cold Climate

This study examined the functionality of a porous pavement storm-water management system in coastal New Hampshire where 6 months of subfreezing temperatures typically occur. The usage of porous pavements for storm-water management in northern climates has many challenges, most of which relate to the extreme cold and significant frost penetration into the porous media. The porous pavement system was monitored for hydraulic and water-quality performance from 2004 to 2008. The use of porous pavements for parking lots for new and redevelopment projects are onewatershed-based strategy that can both mitigate impacts for new development and reverse impacts in areas with redevelopment. Surface infiltration capacity and frost penetration were measured monthly to assess winter performance. Because of the well-drained nature of the porous pavement and reservoir base, issues related to frozen media were minimized. Significant frost penetration was observed up to depths of 71 cm without declines in hydrologic performance or observable frost heave. No consistent statistical difference was observed for seasonal hydrologic performance with mean infiltration capacity ranging from 1,490 to 2;690 cm=h. Adverse freeze-thaw effects, such as heaving, were not observed, and for that reason, the life span is expected to exceed that of typical pavement applications in northern climates. Observed hydrologic response resembled shallow depth groundwater drainage, as is the goal for low-impact development designs. Peak flows were reduced by 90% to 0:58 m 3 =s=km 2 � 0:74 in comparison with standard impervious cover ¼ 5: 5m 3 =s=km 2 � 7:7. There was exceptional water-quality treatment performance for petroleum hydrocarbons, zinc, and total suspended solids with nearly every value below detection limits. Only moderate removal was observed for phosphorous, and treatment for nitrate (NO3) was negative. DOI: 10 .1061/(ASCE)EE.1943-7870.0000459.

Polycyclic Aromatic Hydrocarbons in Stormwater Runoff from Sealcoated Pavements

Coal-tar based sealcoat has been identified as a source of polycyclic aromatic hydrocarbons (PAHs) in the environment. This study measured the long-term release of PAHs in parking lot runoff and found that the presence of coal tar sealant increased the mass of PAHs released in runoff by over an order of magnitude. PAH concentrations in stormwater from two coal tar sealed parking lots and one unsealed parking lot (control) were monitored over a two-year period. The measured flow volume and concentrations were used to calculate a mass of 9.8-10.8 kg total Σ16 PAHs per hectare exported in stormwater runoff from the two sealed parking lots and 0.34 kg total Σ16 PAHs per hectare from the unsealed control. The study also measured sediment PAH concentration changes in a receiving drainage and found that even partial coverage of a drainage area by coal tar sealant resulted in measurable increases in PAH sediment concentrations; PAH concentrations in sediment in a stormwater swale receiving runoff from both sealed and unsealed lots increased near the outfall from less than 4 mg/kg prior to sealing to 95.7 mg/kg after sealing. Compound ratio plots and principal components analysis were examined and were able to clearly differentiate between pre- and postsealant samples.

Comparison of Maintenance Cost, Labor Demands, and System Performance for LID and Conventional Stormwater Management

The perception of the maintenance demands of Low Impact Development (LID) systems represents a significant barrier to the acceptance of LID technologies. Despite the increasing use of LID over the past two decades, stormwater managers still have minimal documentation in regards to the frequency, intensity, and costs associated with LID operations and maintenance. Due to increasing requirements for more effective treatment of runoff and the proliferation of total maximum daily load (TMDL) requirements, there is greater need for more documented maintenance information for planning and implementation of stormwater control measures (SCMs). This study examined seven different types of SCMs for the first 2-4 years of operations and studied maintenance demands in the context of personnel hours, costs, and system pollutant removal. The systems were located at a field facility designed to distribute stormwater in parallel, in order to normalize watershed characteristics including pollutant loading, sizing, and rainfall. System maintenance demand was tracked for each system and included materials, labor, activities, maintenance type, and complexity. Annualized maintenance costs ranged from

Comparison between the Nitrogen Fluxes from Composting Farm Wastes and Composting Yard Wastes

2,280/ha/yr for a vegetated swale to

Storm Water Low-Impact Development, Conventional Structural, and Manufactured Treatment Strategies for Parking Lot Runoff: Performance Evaluations Under Varied Mass Loading Conditions

7830/ha/yr for a wet pond. In terms of mass pollutant load reductions, marginal maintenance costs ranged from

On Parameter Estimation of Urban Storm-Water Runoff Model

4-

Sediment Monitoring Bias by Automatic Sampler in Comparison with Large Volume Sampling for Parking Lot Runoff

8 per kg/yr TSS removed

Economic and Adaptation Benefits of Low Impact Development

A nitrogen transport and mass-balance study was performed at a large-scale composting facility in order to evaluate the impact of such facilities on groundwater quality. In the soil zone, soil moisture NO3-N concentrations in excess of 100 mg/L were consistently observed at depths as great as 1.5 m below a farm waste windrow, and reached levels as high as 900 mg/L by the end of the composting process. There was a strong inverse relationship between NH4-N changes in the farm waste and NO3-N changes in the soil directly below the windrow. Little attenuation occurred as NO3-N was transported downward through the soil. NO3-N in soil moisture 1.5 m below the yard waste remained at ambient levels for much of the two-month sampling period. Quantified nitrogen losses during the composting process were nearly 10 times higher in the farm waste than in the yard waste. Of the nitrogen species sampled, dissolved NO3-N was by far the predominant pathway for nitrogen loss from the composting farm waste, while gaseous N2O losses predominated in the composting yard waste. The major factors determining the degree to which nitrogen was lost during the composting process were waste characteristics of: the type of organic carbon present, the percentage of inorganic nitrogen, the bulk density, and moisture content.

Modeling Urban Storm-Water Quality Treatment: Model Development and Application to a Surface Sand Filter

Eleven storm water treatment strategies were evaluated for water quality performance and storm volume reduction during rainfall-runoff events between September 2004 and August 2005. Evaluated treatment strategies included structural best management practices (BMPs) (swales, retention ponds), low-impact development (LID) designs (treatment wetland, filtration and infiltration designs), and manufactured BMPs (filtration, infiltration, and hydrodynamic separators). Contaminant event mean concentration, performance efficiency, and mass-based first flush were evaluated for storms with varying rainfall-runoff characteristics. Previous research demonstrated that treatment performance of storm water control measures varies widely in response to site-specific contaminant loading functions. For that reason, the devices were tested in parallel, with a single influent source providing uniform loading to all devices. Treatment strategies were uniformly sized to target a rainfall-runoff depth equivalent to 90% of the a...

Unsaturated Flow Functions for Filter Media Used in Low-Impact Development—Stormwater Management Systems

An existing accumulation and wash-off model was applied and calibrated on a standard asphalt parking lot located in the northeastern United States. The field measured data consisted of rainfall, flow, and runoff samples taken from over 26 storm events monitored from 2004 to 2006. The contaminants under consideration include: total suspended solids, total petroleum hydrocarbons-diesel range hydrocarbons (TPH-D), dissolved inorganic nitrogen (DIN) (comprised of nitrate, nitrite, and ammonia), and zinc (Zn). The objective of the study was to provide probability distributions of model parameters for contaminants that have not been documented much (TPH-D, DIN, and Zn). The best fitting parameter values were found on a storm by storm basis. Subsequently, the range and variability of these parameters are provided for modeling purposes and other urban storm-water quality applications. A normal distribution was fitted to the optimized model parameter values to describe their distributions. A simulated annealing al...