 |
Pushpoint Sampling for Defining Spatial and Temporal Variations in Contaminant Concentrations in Sediment Pore Water near the Ground-Water/Surface-Water InterfaceBy Marc J. Zimmerman, Andrew J. Massey, and Kimberly W. CampoIn cooperation with the U.S. Environmental Protection Agency Measurement and Monitoring for the 21st Century InitiativeScientific Investigations Report 2005-5036 |
This report is presented in Portable Document Format (PDF).
Printable tabloid cover (234 KB)--1 page
Inside back cover (392 KB)--1 page
Report (1,264 KB)--75 pages
The citation for this report, in USGS format, is as follows:
Zimmerman, M.J., Massey, A.J., Campo, K.W., 2005, Pushpoint Sampling for Defining Spatial and Temporal Variations in Contaminant Concentrations in Sediment Pore Water near the Ground-Water/Surface-Water Interface: U.S. Geological Survey Scientific Investigations Report 2005-5036, 70 p.
For more information about USGS activities in Massachusetts and Rhode Island, visit the USGS MA-RI Water Science Center Home Page.
During four periods from April 2002 to June 2003, pore-water samples were taken from river sediment within a gaining reach (Mill Pond) of the Sudbury River in Ashland, Massachusetts, with a temporary pushpoint sampler to determine whether this device is an effective tool for measuring small-scale spatial variations in concentrations of volatile organic compounds and selected field parameters (specific conductance and dissolved oxygen concentration). The pore waters sampled were within a subsurface plume of volatile organic compounds extending from the nearby Nyanza Chemical Waste Dump Superfund site to the river. Samples were collected from depths of 10, 30, and 60 centimeters below the sediment surface along two 10-meter-long, parallel transects extending into the river. Twenty-five volatile organic compounds were detected at concentrations ranging from less than 1 microgram per liter to hundreds of micrograms per liter (for example, 1,2-dichlorobenzene, 490 micrograms per liter; cis-1,2-dichloroethene, 290 micrograms per liter). The most frequently detected compounds were either chlorobenzenes or chlorinated ethenes. Many of the compounds were detected only infrequently. Quality-control sampling indicated a low incidence of trace concentrations of contaminants. Additional samples collected with passive-water-diffusion-bag samplers yielded results comparable to those collected with the pushpoint sampler and to samples collected in previous studies at the site.
The results demonstrate that the pushpoint sampler can yield distinct samples from sites in close proximity; in this case, sampling sites were 1 meter apart horizontally and 20 or 30 centimeters apart vertically. Moreover, the pushpoint sampler was able to draw pore water when inserted to depths as shallow as 10 centimeters below the sediment surface without entraining surface water. The simplicity of collecting numerous samples in a short time period (routinely, 20 to 30 per day) validates the use of a pushpoint sampler as a highly effective tool for mapping the extent of contaminated subsurface plumes, determining their constituents and loadings, and performing technical studies that may be relevant to bioremediation and other activities.
Abstract
Introduction
Purpose and Scope
Study-Area Description
The Pushpoint Sampler
Study Design
Initial Testing
Field Study
Sampling Procedures
Quality Control
Trip Blanks
Equipment Blanks
Replicates
Overview of Data Collection
Spatial and Temporal Variability of Specific Conductance and VOC Concentrations
Specific Conductance
Volatile Organic Compounds
Summary and Conclusions
Acknowledgments
References Cited
1. A, the 91-centimeter-long PushPoint Extreme Sampler, and B, closeup of the slotted screen at the tip
2. The study area, Mill Pond, Sudbury River, Ashland, Massachusetts
3. Sample collection from boat on the Mill Pond, Sudbury River, Ashland
4. Transect A extending from near shore into the Sudbury River, Ashland
5. Schematic diagram depicting layout of transects A and B in relation to Sudbury River shoreline at the Mill Pond and flow direction, Ashland
6. Specific conductance at depths of A, 10 centimeters; B, 30 centimeters; and C, 60 centimeters below sediment surface along transect A
7. Specific conductance at depths of A, 10 centimeters; B, 30 centimeters; and C, 60 centimeters below the sediment surface along transect B
8. Concentrations of trichloroethene (TCE) at three depths below the sediment surface along transect A in A, June 2002; B, September 2002; C, April–May 2003; and D, June 2003, Mill Pond, Sudbury River, Ashland
9. Concentrations of trichloroethene (TCE) at three depths below the sediment surface along transect B in A, June 2002; B, September 2002; C, April–May 2003; and D, June 2003, Mill Pond, Sudbury River, Ashland
10. Concentrations of 1,2-dichlorobenzene (1,2-DCB) at three depths below the sediment surface along transect A in A, June 2002; B, September 2002; C, April–May 2003; and D, June 2003, Mill Pond, Sudbury River, Ashland
11. Concentrations of 1,2-dichlorobenzene (1,2-DCB) at three depths below the sediment surface along transect B in A, June 2002; B, September 2002; C, April–May 2003; and D, June 2003, Mill Pond, Sudbury River, Ashland
12. Concentrations of trichloroethene (TCE) and cis-1, 2-dichloroethene (cis-1,2-DCE) at sediment depths of A, 10 centimeters; B, 30 centimeters; and C, 60 centimeters along transect A, Mill Pond, Sudbury River, Ashland, June 2003
13. Concentrations of trichloroethene (TCE) and cis-1, 2-dichloroethene (cis-1,2-DCE) at sediment depths of A, 10 centimeters; B, 30 centimeters; and C, 60 centimeters along transect B, Mill Pond, Sudbury River, Ashland, June 2003
14. Concentrations of chlorobenzene and related compounds at sediment depths of A, 10 centimeters; B, 30 centimeters; and C, 60 centimeters along transect A, Mill Pond, Sudbury River, Ashland, June 2003
1. Staff-gage height, streamflow, and piezometer readings during study periods, Mill Pond, Sudbury River, Ashland, Massachusetts, 2002–03
2. Number, frequency of detection, and concentration ranges of volatile organic compounds detected in primary (that is, not including quality-control replicates) samples reported in this study
3. Volatile organic compounds detected in selected monitoring locations for the Nyanza Superfund Site, Ashland, 1998, 2000–2003
4. Results of sampling pore water along transect A during field studies, Mill Pond, Sudbury River, Ashland, 2002–03
5. Results of sampling pore water along transect B during field studies, Mill Pond, Sudbury River, Ashland 2002–03
| AccessibilityFOIAPrivacyPolicies and Notices | |
  |
|