Quality Assurance Project Plan Including Sampling And Analysis Plan (Page 38 of 67) in pdf

Hunters Point Shipyard Parcel F ESTCP Demonstration Plan

Appendix A: Quality Assurance Project Plan

Sample jars containing whole M. nasuta clam tissues will be received frozen from Stanford with no prior

homogenization. Each sample jar will contain one whole clam tissue (1-2g). These clam tissues will be

grouped in sets of six (or less based on survival rate) according to the clam tubes from which they were

retrieved in the field. Each set of six clams will be thawed and combined (6-12 g) into a stainless steel

mortar that is set in a bath of liquid nitrogen. Using a pestle, the combined tissue sample will be

thoroughly pulverized and homogenized until the tissue has the consistency of a powder. After

homogenization, there should be no chunks visible or pieces of whole tissue left. At this point, a 1-g

aliquot will be removed for dry weight determination and a 1-g aliquot will be removed for lipid weight

determination. After removing these aliquots, the resulting homogenate (4-10g) from each sample will be

split into two equal parts (2-5g). One split will be analyzed by ERDC, while the other will be immediately

frozen and later shipped on dry ice to BDO for archival.

If there is 4-5g of total tissue mass in the ERDC split, ERDC may further divide their split into two parts

so that they have backup sample of their own. The extraction procedure will begin by weighing 2-3g

aliquots of each ERDC split into 60mL vials. 0.1mL of surrogate will be added to each sample, including

QC samples, and 0.1mL of spike will be added to the appropriate samples. 1g of hydromatrix will be

added and stirred into each sample. 50mL of hexane will be added to each vial with sample. The vials will

be shaken to ensure sample is free flowing and has not clumped together. Vials will be placed in

ultrasonic bath and sonicated overnight.

The extracted samples will be filtered through a funnel containing sodium sulfate into TurboVap tubes.

The vials and funnels will be rinsed several times with hexane. The TurboVap tubes will be placed in the

TurboVap and the extracts will be evaporated to approximately 1mL before subsequent cleanup.

Extract cleanup will follow EPA Method 3630C (US EPA, 1996). Solvent-rinsed chromatography

columns (15 x 250 mm, Kimble/Kontes, Vineland, NJ) will be packed with a plug of glass wool, followed

by 3 g deactivated silica gel (3.3 % moisture) and topped with a small amount of sodium sulfate. Columns

will be pre-rinsed with 20 mL hexane. Following addition of sample extracts, columns will be eluted with

80 mL of hexane. Samples will then be concentrated on a Zymark TurboVap II to approximately 2 mL.

Extracts will be transferred to clear 12 mL vials, 2 mL of concentrated sulfuric acid will be added, and the

mixture will be vortexed for 30 s. The hexane layer will be transferred to another 12 mL vial and the

remaining acid rinsed with a small amount of hexane that will be combined with the primary extract.

Approximately 1mL of water saturated with sodium bicarbonate will be added to the vial with the extract

to neutralize any traces of acid. The vial will be shaken for several seconds, and then the water will be

carefully removed from the extract. A small amount of sodium sulfate will be added to remove any

remaining water. The extract will be concentrated under a stream of nitrogen to less than 1mL and then

transferred to a 2mL chromatography vial. The 12mL vial will be rinsed with 0.5mL of hexane which will

be also added to the 2mL vial. The extract will be given a final nitrogen concentration to less than 1mL.

Internal standard will be added and the extract will be adjusted to 1mL.The PCB analysis of the resulting

extracts will be performed according to Section A.3.4.2.3.

Aliquots of wet homogenized amphipod tissue (100 mg) will be weighed into certified pre-cleaned 20 mL

vials. A surrogate, 2,4,5,6-tetrachloro-m-xylene, will be added to each sample to monitor method

efficiency. Hexane (10 mL) will be added and each sample extracted twice for a total of 6 minutes using

a Fisher Scientific Model 550 Sonic Dismembrator with microtip probe. Combined solvent layers will be

transferred to a prepared silica gel column and cleaned up following EPA Method 3630C (US EPA,

1996).

A.3.4.2.2 Community Structure Analysis of Benthic Organisms from Surface Sediment Quadrats

To isolate treatment effects upon benthic recolonization, community structure, and organism growth, the

benthic community samples shall be analyzed for macrofaunal composition, using a suite of appropriate

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Quality Assurance Project Plan Including Sampling And Analysis Plan Page 38

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