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Abstract:Spatial variability of soil types and surface horizon thickness were investigated along a 0.2 km transect near an upland valley side slope in the North Carolina Coastal Plain. Previous studies have shown a variable but systematic pattern of soil properties and surface thickness near such "dry edges." The edge effect model successfully predicts the highly variable pattern of soil cover found at the study site, and explains the generally thick (mean ~1 m) surface horizon thickness on the upland portion of the site. It does not explain the 10-fold variation in A and E-horizon thickness (15 to 152 cm) over less than 200 m, the irregular spatial pattern, and the lack of any trend with respect to distance from the dry edge. The broad-scale patterns governed by drainage and topographic factors have superimposed short-range variability, probably associated with biological factors such as tree throw and faunalturbation.

In the past, we measured the filter freeboard (the measurement from the top of the filter media to the top of the washwater trough) quarterly. To accomplish this task, we had to first drain the filter, then, standing on top of the washwater troughs, measure at various places to get an average. This practice was obviously hazardous because someone had to straddle the washwater troughs and enter a confined space to take the measurements. Adding to our difficulties, we did not have a good way to measure filter bed expansion during a filter backwash. We constructed a gadget to perform this task in a safer, more efficient manner. A list of materials and construction information is provided.

Chemical metering pumps can be difficult to prime. This device saves many hours of labor spent in disconnecting tubing and checking pump heads and foot valves for priming problems. The priming device has also improved our customer and employee relations because it reduces outages and downtime due to meter pump priming problems.