The basic procedure was as follows: drillers install pilot casing to stiff material (usually 4-6 feet below mudline); CPT is assembled using the amount of rods needed to set the cone at the top of mudline. CPT assembly consists of cone penetrometer and drill rods with cord threaded through each running from the cone penetrometer to the computer on barge deck. A second “depth counter” instrument is hooked to the drill rig and a cord feeds the depth info to the computer as the cone penetrometer is pushed into the sediment. Real time data is collected from the cone penetrometer on the physical parameters of the sediment as it pushes through. The CPT engineer watches the computer screen to determine when refusal is reached - this is easily observed when the TSF (tons per square feet) value increases quickly as the force needed to push the cone penetrometer increases when it encounters rock. The CPT engineer then stops the sampling and saves the data on his computer. The drillers pull up the CPT equipment and pilot casing and decontaminate them using a low pressure wash and alconox scrub. The barge is then moved to the next location and the procedure is repeated.
|Close-up view of cone penetrometer instrument, October 20, 2009. Cone Penetrometers (CPTs) evaluate the bearing capacity of the material it is thrust into. CPT instruments can record material data as discretely as every 2 centimeters, to give engineers very accurate information on how the material being measured will behave, for example when dredged or capped, or to evaluate seismic stability for a structure like a confined disposal facility.||October 1, 2009 - WB-36 boring location. The photo is looking north across the Willamette River with dock number 2 in the background. ||October 1, 2009 - Bald eagle perched on power pole upland of Dock 2 at the Arkema site during sampling. Bald eagle eggs have been heavily impacted by DDT/DDX contamination in the environment, which among other impacts make their eggs very brittle.|
|Brown colored seep downgradient from the former salt pads at the Arkema Site near sampling activities, September 17, 2009. This seep was previously sampled under ODEQ direction and not found to contain any different characteristics seepage than what is otherwise present in porewater at the site (ie. chrome, salts monochlorobenzene, DDX).||Integral staff viewing river staff gage (white staff in distance) using binoculars to determine river elevation (monitored every 30-45 minutes). Several surveyed staff gauges are located on the docks to aid in calculating changes to river stage. River levels are important to determine so that the correct sediment sampling depths that were targeted are achieved, to the extent possible.||"Spud" (large piling, picture center) used to moor the sampling barge. These pilings are dropped in place of anchor's to keep the barge extremely stable during sampling activities, September 11, 2009.|
|Integral (Arkema/LSS contractor) crew collecting equipment rinsate sample at WB-48, September, 10, 2009. Rinsate samples are taken to check that field procedures for cleaning sampling tools between sample locations is working--and that contamination is not being transferred between the sites, which could give misleading results.||Driller making 2nd cut lengthwise down vibracore tube used to obtain 0-10’ core at WB-49, September 9, 2009. After cutting, the two halves of the core are homogenized and then sent to the lab for analysis.||Driller (Boart Longyear) using bobcat to deliver split spoon sampler from WB-47 boring to barge for processing, September 8, 2009. The hose coiled up in the foreground provides potable water from upland for decontamination aboard the barge for sample processing.|
Drill rig sampling at WB-47 on Arkema beach, September 8, 2009. Note railroad bridge and exclusion zone, yellow tape in the background.
Drillers lowering empty IDW drums onto barge from Dock 2 via rope, September 2, 2009. The shoreline and deteriorating docks present limited access currently to move gear on and off the barge.
|Integral crew disposing of leftover sediment from vibracore sampler into investigation derived waste (IDW) drum, September 2, 2009. IDW waste is disposed of in an offsite landfill.|
Homogenized sample from 0-2' at WB-44; sheen is visible on the sediment, September 2, 2009. Samples are mixed (homogenized) to ensure a representative sample interval is sent to the lab. A separate sample will be analyzed for VOCs due to the presence of the sheen.
Integral staff taking photo ionization detector (PID) reading in driller’s breathing zone, September 1, 2009. PID readings help to determine if the workers are being exposed to unnacceptable levels of certain chemicals, such as volatile organic compounds, for their safety.
|Recovery of 6 feet of sediment in vibracore tube, August 27, 2009. It was hoped use of the vibracore would decrease sloughing that is being observed with the 2 foot intervals collected in the 5-foot long split spoon. The production rate could also improve since 10 feet of sediment is collected at one time. The vibracore sampling tube is 12 feet long, 3 inches in diameter, and made of thin aluminum. There is a plunger at the top, and a “shoe” with thin flappers at the bottom that can easily move through the soft sediment at the surface of the river bottom and then catch the sediment when the tube is pulled up. |
|Removing 12 foot vibracore tube containing sample. The barge was positioned offshore at WB-50. Drilling was initiated by attempting a “vibracore” sample to obtain the 0-10’ interval. ||Shoe of vibracore showing flappers or fingers that catch the sediment when the sample tube is removed (pulled up), August 27, 2009. Arkema beach/shoreline in background, looking south/southwest||Power wash decon station in background, August 26, 2009. Note pump (background) used to pump decon water to drum (foreground). Decon water is collected as cleaners or detergents that might be used in the decontamination process can be harmful to aquatic life.|
|Drillers opening split spoon sampler to pull out a sample, August 26, 2009.||Drillers (Boart Longyear) using bobcat to carry split sampling spoon with sample down the beach to barge from WB-55 to barge, August 26, 2009. Due to low tide, some samples had to be taken on shore and the core transported to the barge mounted sample processing area.||Drill rig positioned at WB-64, August 25, 2009. Due to low river levels, the drill rig had to be brought on shore to sample this area.|
|New decon curtain to limit material blowing downwind during decontamination of the core segments, August 24, 2009.||Workers pulling samples out of cores, August 24, 2009. Workers used short sleeves to limit heat stress, but this could exacerbate dermal exposure to contaminants. Long sleeve tyvek and other cooling means may have to be implemented.||Drill rig during clean-up/containment of oil leak. Notice the sorbent pad applied in the open hole in the middle of the barge used for drilling to aborb and contain the oil. The oil leak originated from the drill rig's hydraulic lines. Coring was shut down until this leak could be fixed, August 21, 2009.|
|LSS contractor (Boart Longyear) driller measuring depth to sample, August 20, 2009.||Small Pacific lamprey found in 0-2’ interval at WB-63, August 20, 2009||Boring WB-63, 10-12’ interval, August 20, 2009|
|Taking photo ionization detector (PID) reading of sediment from boring WB-66, 0-2 foot interval. PID readings can give an estimate of levels of volatile compounds emanating from the sample being handled, to ensure proper worker respiratory protection measures are being taken.||Photo of exclusion zone aboard the sampling barge. The barge is separated into an exclusion zone (sample handing), a contamination reduction zone (CRZ) to clean off contaminants, and a clean zone (e.g. for drinking fluids, eating lunch), August 18, 2009.||Photo of drill rig used to obtain core samples from aboard the barge, looking shoreward to the Arkema site, August 18, 2009.|
|Photo of core from WB-65, 0-2 foot interval (poor recovery). Poor recovery sometimes occurs due to lack of material compaction, causing material to fall out of the tube when the core is withdrawn from the river bottom, August 18, 2009.||Rhone Poulenc wells being sampled on the beach by AMEC near WB-65 boring (photo looking upriver along Arkema beach). Rhone Poulenc groundwater plumes intersect the Willamette River underneath the Arkema Site, August 18, 2009.||WB-65 core sample being taken on August 18, 2009. The drill rig operator was reminded to put gloves on (at left) after this photo was taken due to the high levels of DDX, monochlorobenzene, and other chemicals present in many samples being taken.|
|Cleaning the outside of core tubes after withdrawing them from the bottom at WB-65 (background looking upriver), August 18, 2009. Basalt was found to be much shallower here than expected. Both geology and contaminant information will be used to compare cleanup alternatives, and also for later design work.||CDM staff were on site during sampling both to oversee sample collection, and also to ensure adherence to the site health and safety plan.||Site health and safety briefing before the start of work, August 18, 2009. Willamette River, sampling barge, and McCormick and Baxter Site visible in background.|