ATTACHMENT 6 - Technical Exhibit C - Homogenization SOP.pdf

ATTACHMENT 6- TECHNICAL EXHIBIT D

Homogenization SOP

Purpose:

The purpose of this protocol is to define procedures for compositing and homogenization of sediment for dredged material evaluations.

Procedure Summary:

1. Field collect sediment material into HDPE buckets, with optional PTFE liner (not included in this SOP)

2. Ship to laboratory under chain of custody

3. Receive field collected sediment in HDPE buckets

4. Homogenize and aliquots of discrete sediments (archive for potential analytical chemistry) in pails

5. Composite additional discrete sediment and homogenize in a HDPE or SS barrel to create zone composite

6. Allocate composited zone material into HDPE buckets for storage and use (TFE liner optional)

Procedure:

1. Receive material from field crew

1.1. Sign chain of custody forms to transfer custody

1.2. Open field buckets to check temperature and check sample condition on receipt

1.3. Label all containers with project POC name and phone extension

1.4. Place all material in locked, walk-in cooler (4 C)

1.5. Log samples into laboratory sample tracking sheets

2. Homogenization of discrete sediments

2.1. Locate and remove all discrete sediment samples from one zone and take to mixing bay

2.1.1. Log in activity in walk-in cooler access form

2.2. If using bucket liner, empty discrete sediment samples from their containers into a precleaned 23 quart

SS pail (section 3.3) for each discrete sediment

2.2.1. Stainless steel spatula to fully remove homogenized material from TFE bag or liner

2.2.2. Homogenize each discrete sediment, in SS pail if using liner or in bucket if not, until texture is consistent and for at least 5 minutes with mixer

2.2.3. Remove aliquot necessary from each homogenized discrete sediment for chemical analysis

(the ERDC Environmental Chemistry Branch will supply personnel and guidance)

2.2.4. Complete chain of custody for analytical samples

2.2.5. Set aside 0.5 (up to 2 gallons if bioassays are considered) of discrete sediment for potential discrete sample testing (using two 1 gallon clean HDPE or glass containers) for archiving

2.3. Clean SS prop and shaft as per Section 3 between each discrete sediment

2.4. Place remaining homogenized discrete sediments in equal volumes into pre-cleaned 30-55 gal SS or pre-cleaned HDPE mixing drum

2.4.1. Transfer material via pouring into drum and fully remove the sediment from demarcated pail with SS spatula

2.4.2. Document the amount of each discrete material to make the composite in a new composite sediment CoC and a supplemental compositing data sheet

2.5. Mix all discrete sediments together until completely homogenized (minimum of 5 minutes) with large mixer sized for drum (two 11 inch cm diameter props)

2.5.1. Remove aliquot necessary from homogenized zone for chemical analysis (the ERDC

Environmental Chemistry Branch will supply personnel and guidance)

2.5.2. Complete chain of custody for analytical samples

2.5.2.1. Pre-clean HDPE buckets according to section 3.1.

2.5.3. Place remaining homogenized material into pre-cleaned or Teflon/PTFE lined HDPE buckets and place in walk in cooler

2.5.3.1. Transfer material via pouring or scooping into receiving container and fully remove the sediment from drum with SS spoons, scoops, spatula and plastic scraper

2.6. Complete new sample tracking log sheets for composited samples. Clean all equipment as described in

Section 3.

2.7. Repeat for remainder of zones and discrete sediment samples

3. Equipment decontamination

3.1. HDPE buckets and lids (5 gallon)1

3.1.1. Obtain new buckets

3.1.2. High pressure Tap water rinse

3.1.3. Soap water rinse: liquanox / water mix and scrub brush

3.1.4. Water rinse 3 times (tap)

3.1.5. Solvent rinse (isopropyl alcohol)

3.1.6. Water rinse 3 times (tap)

3.1.7. Acid rinse using squirt bottle (1% nitric acid)

3.1.8. DI water rinse 3 times

3.2. Impeller and shaft (SS)2

3.2.1. High pressure water rinse of excess material off into waste vessel

3.2.2. Scrub prop and shaft with liquanox / water mix and scrub brush

3.2.3. Rinse soap off of prop and shaft 3 times (tap water)

3.2.4. Rinse prop and shaft with solvent (acetone)

3.2.5. Rinse solvent off with water 3 times (tap)

3.2.6. Final rinse with DI water

3.2.7. Dry (machine wipe)

3.3. Pail, drum and spatula (SS)2

3.3.1. High pressure water rinse of excess material off over drainage grate

3.3.2. Scrub prop and shaft with liquanox / water mix and scrub brush

3.3.3. Rinse soap off of from surfaces 3 times (tap water)

3.3.4. Rinse surfaces with solvent (acetone)

3.3.5. Rinse solvent off with water 3 times (tap)

3.3.6. Final Rinse with DI water 3 times

3.3.7. Dry (machine wipe)

1 Acetone is not to be used with plastic / HDPE materials

2 Acid is not to be used with SS materials