Farm River

Geomembrane These liners chiefly provide impermeable barriers. They can be characterized as (1) solid waste containment hazardous landfill, landfill capping, and sanitary landfill (2) liquid containment canal, chemical/brine pond, earthen dam, fish farm, river/coastal bank, waste-water, and recreation (3) mining, leach pad and tailing ponds and (4) specialties floating reservoir caps, secondary containment, tunnel, erosion, vapor barrier, and water purification. Plastics used include medium to very low density PE, PVC, and chlorosulfonated PE (CSPE). (The Romans used in their land and road constructions what we call geomembrane.)... 

Figure 1 Comparison of the change in sea level measured in a tide gauge in New York versus the excess Ph derived from the atmosphere in a core from the Farm River Salt Marsh, Branford, Connecticut (source McCaffrey and...

Fig. 5. Depth versus time curves for the Farm River (Connecticut) salt marsh based on Pb dating with a comparison with the tide-gauge record for New York City. (From McCaffrey and Thomson, this volume.)...

Table 1. Calculated Excess Metal Flux to the Surface of the Farm River Salt Marsh Compared to Measured Atmospheric Deposition Rates at Selected Sites...

Farm River salt marsh (Branford, Connecticut) Long Island Sound sediment cores 13 19 13... 

Once promising areas within the Farm River marsh were selected, they were examined in the field. Several trial cores were raised using a tool designed for this task (McCaffrey, 1977) and local residents were inter-... 

The chosen area (Fig. 1) is located in the eastern lobe of the Farm River salt marsh (4ri6 00"N, 72°5r06 W), 7.9 km southwest of the center of... 

Fig. 2. Vertical section of the Farm River salt marsh, showing. position of the dated core and general stratigraphy.

Direct evidence for the formation of authigenic metal sulfide comes from x-ray microprobe and light-microscope examination of the salt-marsh sediments. In the presence of sulfur, iron monosulfides react to form pyrite, FeS2, which is known to occur as distinctive, characteristic aggregates of octahedral microcrystals of FeSj (framboids Berner, 1970 Sweeney and Kaplan, 1973). In the Farm River samples, framboidal FeSj was found to be common within at least the upper 14 cm of core examined, either as discrete framboids of 10- im diam. (Fig. 7) or as ordered clusters of framboids. Inspection of polished thin sections reveals a frequent association with the organic matrix, which appears to act as a template for their formation (see Fig. 8). 

Table II. Trace-Metal, Radiochemical, and Bulk-Density Data for Farm River Salt-Marsh Core... 

Table IV. Standing Crop of Excess Pb in Farm River Upland Soil"...

Analyses of trace metal and sulfate in pore water provide evidence of diagenetic change in salt-marsh sediment. Rapidly processed cores from the Indian Neck and Farm River sites showed normalized SO4/CI ratios of greater than 1 at certain depths (Table VI). The cores also contained measurable concentrations of dissolved Mn and, at the Farm River site, Fe. The high Mn concentrations seen in Figs. 9 and 10 coincide with the maximum SO4/CI ratio. Other metals were not detected, with the possible exception of trace amounts of Zn in one Indian Neck core. 

Fig. 11. The depth distribution of total activity of Pb in contiguous slices of peat from the Farm River salt marsh shows that the semilog plot is convex in the region about 34 cm. Below 34 cm to the top of the distinct D. spicata rhizome layer at 50 cm, the activity is low and approximately constant, averaging 0.83 dpm gm , which is taken as supported background. Below this layer, the supported Pb activity is irregularly lower. The dominant species of vegetation varies with depth as indicated, but all species found are characteristic of high marsh.

Table IX. Pb Chronology of the Farm River Salt Marsh"...

Such independent estimates are available from direct measurements of Pb in total precipitation and from the standing crops present in undisturbed soils. Previous measurements of the atmospheric flux have been made in New Haven by Benninger (1976) using open-bucket collectors sampled at monthly intervals. Soil-standing crops have been measured at various sites in the eastern U.S., including a forested upland site within the Farm River salt marsh, and are compared in Table X. It is evident that the Pb flux derived from salt-marsh core FRl IB is indistinguishable from the current rate of deposition of Pb from the atmosphere in nearby New Haven. 

It would be interesting to compare the historical record of atmospheric quality found in the salt marsh to independent records of atmospheric burdens of trace metals, but such information is not available. It is possible, however, to use metal-production figures as a crude index of atmospheric emission. As an example, the historical increase in the primary production of Cu in the U.S. as a whole is compared to the increase in Cu deposition recorded in the Farm River salt marsh in Fig. 21. It is evident that the increase in Cu flux recorded in the salt marsh is in general agreement with the production trend over the period of record. 

Based on a mean-residence time of days, the general eastward sweep of air across the continent (Van Cleef, 1908) and analyses of back trajectories of air masses (Cogbill and Likens, 1974) indicate that virtually any source east of the Mississippi or in southern Canada must be considered a possible contributor to the record of trace metals uncovered in the Farm River salt marsh. 

Indeed, salt marshes like the Farm River marsh, which lie adjacent to well-stratified tidal rivers, seem biased to receive soil from upland... 

Peat from the Farm River salt marsh, an estuarine marsh on the submerging coast of Connecticut near New Haven, was sampled by raising essentially undisturbed, meter-long cores, and was found to record trace-metal deposition from the atmosphere and sediment erosion from the land during the past century. 

Farm River, Connecticut 210pb 0.5 McCaffrey and Thomson (1980)... 

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