Northeastern Section - 48th Annual Meeting (1820 March 2013)
Paper No. 59-13
Presentation Time: 1:30 PM-5:00 PM

ANALYSIS OF TOXIC METALS IN STREAM SEDIMENTS IN THE MIDDLETOWN PEGMATITE DISTRICT, CONNECTICUT

LAFLEUR, Ryan1, CROSS, Amanda1, and EVANS, Mark A.2, (1) Central Connecticut State University, Department of Physics and Earth Science, New Britain, CT 06050, lafleurker@gmail.com, (2) Department of Physics and Earth Science, Central Connecticut State Univ, 1615 Stanley St, New Britain, CT 06050

The Middletown Pegmatite district in Portland, CThas been mined since the early 1800s. The microcline-quartz-micapegmatites are known for quality beryl minerals, along with over 100 additional minerals, including molybdenite, galena, arsenopyrite, chalcopyrite, and anatase. The purpose of this study was to investigate the effects of past mining on the sediment quality in local streams.

In order to assess the potential for toxic trace metal contamination, 41 sediment samples (<64 micron fraction) were collected from 19 sites located within and outside of the pegmatite district. The streams sampled drain from the adjacent highlands to the east of the mines, westward into the Connecticut River. A weak acid digestion was used to prepare samples for Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES) analysis to determine the concentration of major trace metal elements.

The results show a relatively low concentration of most metals. Arsenic ranges from 0.2 to >3 ppm; beryllium ranges from 0.3 to >5 ppm; cadmium ranges from 0.2 to 3 ppm; cobalt ranges from 0.4 to as high as 76 ppm; chromium ranges from 0.5 to 84 ppm; copper ranges from 2 to 57 ppm; lead ranges from 0.4 to 100 ppm; molybdenum ranges from 0 to >1 ppm; titanium ranges from 8 to 377 ppm; thallium ranges from 0 to 5 ppm; vanadium ranges from 3 to 72 ppm; and zinc ranges from <2 to 74 ppm. Locally, levels of cadmium, chromium, copper, and lead exceed threshold effect concentrations. Thallium locally exceeds ORNL soil phytotoxicity levels, while vanadium exceeds the micro-organism toxicity level.Interestingly, the lowest metal concentrations are in the currently abandoned Hale and Strickland Quarries which are being used as anexplosive storage area and agolf course respectively. The highest metal concentrations are found upstream and to the east of the mines. Also, the cobalt and chromium values are unexpectedly high and suggest possible mineral deposits upstream from our sample locations.

Northeastern Section - 48th Annual Meeting (1820 March 2013)
General Information for this Meeting
Session No. 59--Booth# 23
State and Fate of Urban Watersheds in the Northeast (Posters)
Omni Mount Washington Resort: Grand Ballroom South
1:30 PM-5:00 PM, Tuesday, 19 March 2013


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