Hydrologist, Minnesota Pollution Control Agency, St. Paul, MN
Pages: 9 Published: Jan 1990
Review of ground-water quality data obtained from wells in southwestern Ohio revealed the presence of lead, cadmium, and other heavy metals. Often, no pollution source could be discovered to account for the presence of the heavy metals. In order to establish whether sampling methods were a possible source of contamination, three possible sources of spurious heavy metal values were investigated: (1) the sample preservative, (2) the sampling equipment, and (3) suspended matter in the samples.
The results of this study indicate that painted labels on nitric acid preservative ampules, used during the period 1978 to 1980, contributed to false indications of ground-water pollution. Tests of galvanized steel and polyvinyl chloride bailers showed that this equipment was not a source of lead or cadmium. Statistical analysis of a random sample of ground-water analyses from 70 wells revealed a significant relationship between sediment and lead values. Furthermore, lead values generally increased as the amount of sediment in the sample increased. This relationship probably reflects the presence of lead in particulate matter in the water sample.
Particulate matter found in well water samples can be pieces of corroded well casing or fine sediment from the formation in which the well is screened. Since very little information is available on heavy metals in Ohio's glacial deposits, additional studies of these materials should be done to provide background data for the evaluation of heavy metals in ground water.
total metals, dissolved metals, ground water, heavy metals, sample filtration, sample preservation, bailer, arsenic, cadmium, lead, iron, manganese, aluminum, chromium, copper, nickel, titanium, zinc
Paper ID: STP23416S