Coastal plain ponds around Cape Cod are hotbeds of biodiversity and are thus important areas for conservation. This is especially true given recent anthropogenic nitrogen (N) inputs into these ponds from wastewater treatment plants, septic systems, and fertilized lands. I anticipate researching the source(s) of this N-loading by examining NH4+ and NO3- presence in rainwater and the underground water recharging these ponds, through precipitation collection, wellpoint surveys, and water nutrient analysis. I plan on testing for and determining d15N in the groundwater as an indicator of N stemming from wastewater sources. I will construct water and N budgets for the ponds' watersheds utilizing GIS planning maps of developed/underdeveloped land. The water budget will be informed by an MBL model used to estimate actual evapotranspiration and underground water flow from temperature, precipitation, solar radiation, and plant-soil characteristics measurements. The nitrogen budget will estimate N-loading and attenuation to underground pond seepage points based on assumptions made by Valiela et al. (Ecological Applications 7:358-380). Field survey results will be compared to modeled expectations to evaluate the model's accuracy. This work is part of a collaborative project examining d15N in pond water, sediments, and bordering vegetation/soil to evaluate anthropogenic N-loading effects on ecosystem function.