Surficial water table dynamics will be continuously monitored using Type-F Stevens water level recorders located in the vicinity of high marsh-upland transition zone T-1, T-2 (see attached map). Water level recorders will be referenced to absolute elevations and to shallow groundwater wells in the surrounding hydrologic unit. Charts will be changed at 1 to 4 week intervals. Marsh surface elevation will be determined in the vicinity of the recorder. Plant communities along the transition will be evaluated. Interstitial soil sulfides and redox potential will be monitored. Surveys will be conducted to establish elevations in the areas representative of the water level recorders (see attached map). Leveling will entail the use of surveyor's automatic level, a stadia rod, and accessory equipment. Groundwater wells will be monitored for depth to water table and salinity. Soil redox potential will be determined. Wells with porous bottoms will be monitored with a sulfide probe for interstitial soil sulfide levels along T-1 and T-2.