USGS OFR95-839, Honolulu, Methods, 2a

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Torresan, M.E., Hampton, M.A., Barber, J.H., Jr., and Wong, F.L., 1995, K1-95-HW: Cruise report 1995 - Preliminary results. Phase III: sediment chemistry and biological sampling survey: U.S. Geological Survey Open-File Report 95-839, 94 p.

Summary 1, 2
Introduction
Study Area
Previous Studies
  Designation
  Monitoring 1, 2
Methods
  Vessel
  Navigation
  Sampling
  Subsampling 1, 2
Results
Acknowledgments References 1, 2

Figures
1 Location
2 Box corer

Tables
1 Stations
2 Samples
3 Analyses
4 Bioassay

Appendices
1 Box Cores
2 Custody: Quanterra
3 Custody: Batelle

Sample Handling and Subsampling (1)
Upon recovering the box corer, the box was immediately removed from the box core frame and placed in a special processing box. Cylindrical subcores were then hand pushed by biologists into the upper 5-7 cm of core, to provide the material necessary for benthic species identification and population density. Two (non-mollusc) subcores, about 10.7 cm diameter x 7 cm long, and two (mollusc) subcores about 3 cm diameter x 10 cm long were placed into the central portion of the box and excess water, if present, was siphoned off the core surface. Following placement of the biological subcores, the box core face plate was removed and the core was photographed with a digital camera. Each digital photograph was stored on disk for post-cruise processing and enhancement purposes. The digital photographs were processed with Adobe Photoshop software between stations, and printed out with the aid of a laptop computer and a portable photographic printer. The system negates the use of standard wet chemical photographic processing, and allows post-cruise manipulation for enhancement purposes. Each photograph was then affixed to the box core description forms for archival purposes. Digital photographic data were then stored on 1.3 GB optical discs following the survey for future presentation on CD-ROM. Each box core was then visually described prior to sampling for sediment chemistry and removal of the biological subcores. Appendix 1 is a color-coded visual core description similar to those produced following the 1994 survey. Owing to time and personnel constraints no core slabs were taken, therefore precluding the collection of digital x-radiographs.

Following core photography and description, and prior to the removal of the biological subcores, subsamples were taken for sediment chemistry to determine the concentration of specific EPA-COE- defined contaminants of concern (U. S. Army Corps of Engineers and U.S. Environmental Protection Agency, 1994; Quanterra 1995a-k). Figure 1 and Table 2 shows that a number of the samples were collected from sites occupied in 1994, allowing direct comparison to the 1994 data base. Methodology and protocols employed for the chemical determinations are defined in detail in Table 3 and the Quanterra analytical reports (Quanterra 1995a-h). Sediment chemistry subsampling protocols required detailed and precise sampling procedures to insure against contamination and to guarantee that specific intervals were sampled (dredged material vs native sediment). Subsampling required the use of clean, teflon-coated spatulas. Spatulas were first cleaned with a biodegradable soap and rinsed in distilled water, which was followed by two rinses with reagent grade anhydrous ethyl alcohol. After air drying, spatulas were then rinsed again twice with reagent grade dichloromethane and allowed to air dry. Once dry, the spatulas were used to extract distinct intervals to keep the dredged material separate from native sediment. All samples were then stored in I-CHEM SUPERFUND-ANALYZED, 250 ml jars that include certificates of analysis. A traceable production number, item number, and jar number is provided with each container, and the product meets or exceeds analyte specifications established in the EPA "Specifications and Guidance for Contaminant-Free Sample Containers" for use in Superfund and other hazardous waste programs. The jars meet all EPA specifications for use in the analysis of metals, semivolatiles, pesticides, PCBs, and volatile organics.

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URL: http://geopubs.wr.usgs.gov/open-file/of95-839/05ameth2.html
Maintainer: Carolyn Donlin
Author: Florence L. Wong
Last modified: 01 Oct 97.

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