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| Title | Mercury in Lake Whatcom Sediments: Spatial Distribution, Depositional History, and Tributary Inputs | |||
| Month-Year Published | June 2004 | |||
| Online Availability |
1298 kilobytes, requires version 4.0 or later of Adobe Acrobat Reader Software get Acrobat Reader
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| Short Description |
This report presents results of a 2002-2003 study conducted to investigate the spatial distribution and historical deposition of mercury in Lake Whatcom. The data collected indicate that mercury levels in surface sediments in the lake and surface water entering the lake do not appear to be elevated compared to other areas of Washington. Sediment profiles suggest mercury levels began to increase from background around 1900, reaching peak levels in 1987 to 1995. There is evidence to suggest that mercury concentrations in sediments have leveled off or are decreasing from peak concentrations. A companion report being prepared by USGS will describe regional mercury sources. (Also see abstract below) | |||
| Publication Number | 04-03-019 | |||
| Author(s) | Norton, D. | |||
| Print Availability | ||||
| Number of pages | 38 + app. (132 total) | |||
| Keywords | county, fish, lake, mercury, sediment, study, surface water, water, Whatcom | |||
| Subject Waterbodies |
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| Related Publications | Title | Relationship | ||
| Quality Assurance Project Plan: Mercury in Sediments from Lake Whatcom and Surrounding Lakes: Determination of Spatial and Temporal Patterns and Characterization of Tributary Inputs | similar topic | |||
| Mercury in Edible Fish Tissue and Sediments from Selected Lakes and Rivers of Washington State | similar topic | |||
| Abstract | Long Description |
Concerns over mercury levels in fish from Lake Whatcom prompted the Washington State Department of Ecology to conduct a joint study with the United States Geological Study (USGS) and the Whatcom County Health Department (WCHD) during 2002 and 2003. The primary objective of this work was to evaluate the spatial distribution and historical deposition of mercury in Lake Whatcom. Mercury levels were evaluated by collecting and analyzing bottom sediments from the lake as well as surface water entering the lake from ten tributaries. Data collection and analysis included: 1. During September 2002, 31 surface sediment samples and three deep sediment core samples were collected from Lake Whatcom and analyzed for total mercury. Methylmercury levels also were analyzed in 15 surface sediment samples. 2. Surface water was collected from ten tributaries to Lake Whatcom every other month between July 2002 and May 2003 to calculate mercury loadings. 3. USGS, in cooperation with WCHD, evaluated existing information on potential mercury sources to the lake. They also evaluated sediment core data collected from five nearby lakes in Whatcom County. This information is compiled and evaluated in a companion report prepared by USGS. The data collected indicate that mercury levels in surface sediments from Lake Whatcom and surface water entering the lake do not appear to be elevated compared to other areas of Washington. Surface water concentrations fall at or below levels measured in rainfall at Seattle during 1998 - 2002. Core profiles suggest mercury concentrations began to increase from background levels in Lake Whatcom around 1900. Mercury levels steadily increased in the lake, reaching peak levels in 1987 to 1995. There is evidence to suggest that mercury concentrations in sediments have leveled off or are decreasing from peak concentrations. |
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