The HoltraChem Site (also known as Acme Alkali) is comprised of approximately 24 acres and is located at 636 John L. Riegel Road in Riegelwood, Columbus County, North Carolina. It is surrounded on three sides by International Paper (IP), which is comprised of approximately 1,500 acres. Both HoltraChem and IP border the Cape Fear River. The surrounding area is a mixture of industrial, residential and commercial uses.
The area subject to this removal action includes neighboring IP’s North Bay treatment pond, also known as Cell #2. IP formerly accepted process water generated during chlorine production from the Holtra Chem facility. HoltraChem operated as a chlor-alkali facility using the mercury cell process from 1963 to 1999, when facility operations ceased. HoltraChem was originally constructed to provide chlorine gas, caustic soda, and bleach to the IP facility. Process water from the former HoltraChem facility was reportedly discharged to the northwest corner of Cell #2 via a 16-inch diameter, corrugated galvanized steel pipe from approximately 1963 to the late 1970s or early 1980s.
A time-critical removal action was conducted at the HoltraChem Site during 2003 – 2004, during which containerized hazardous waste and the former cell building were removed. In 2004, an Engineering Evaluation / Cost Analysis (EE/CA) investigation began at the Site. During the EE/CA, the primary contaminants of concern were identified as mercury and PCB Aroclor 1268. Sampling conducted by IP identified PCB Aroclor 1268 at concentrations up to 5,100 mg/kg in Cell #2. PCB contamination extends to a depth of approximately 12 feet below the ground surface. PCB contamination has been found in the adjacent Cape Fear River sediments. IP needs to utilize Cell #2 for the expansion of their landfill sooner than the EE/CA will be completed. Therefore, a Time-Critical Removal Action is being taken to excavate the contaminated Wastewater Treatment Solids (WWTS) from Cell #2 and place the WWTS with concentrations exceeding 50 mg/kg in temporary storage on the HoltraChem Site until the final cleanup plan is selected for HoltraChem. The estimated volume of this material is 6,500 cubic yards. The cleanup goal for this removal action is 11 mg/kg based on the Human Health Risk Assessment for the Holtra Chem Site. WWTS with concentrations between 11 mg/kg and 50 mg/kg will also be excavated, but will be placed in IP’s landfill Cell #1. The estimated volume WWTS with PCB concentrations between 1 mg/kg and 49 mg/kg is 93,500 cubic yards.
The Enforcement Action Memorandum for this time-critical removal action was signed on May 13, 2008. The Effective Date of the Administrative Order on Consent for this removal action was May 20, 2008.
Dave Mattison of th North Carolina Department of Environment and Natural Resources (NCDENR) provided oversight of removal activities during this reporting period (June 30 - July 6, 2008).
* Note: Cell #2 was divided into 100'x100' and 50'x50' grids during the investigation phase. Grids are labeled with a letter and a number. Grid locations can be found in a Figure in the Action Memo.
Activities conducted by the PRPs' contractors during this reporting period included:
Excavation Activities:
* During June 30 - July 3, 2008, approximately 1,632 cubic yards of material with PCB concentrations exceeding 50 mg/kg was excavated and transported from IP to the engineered stockpile on the HoltraChem facility. This material originated in Grids K-5, I-4, I-5, H-5, and J-5.
Dewatering Activities:
* On Saturday, July 5th, 0.15 inches of rain was recorded at the Site.
* During June 30 - July 3, approximately 352,600 gallons of water from Cell #2 was pumped, treated, and discharged to IP. The total volume of water treated since treatment operations began on 6/18/08 is approximately 1,104,800 gallons.
Sampling Activities:
* Confirmation samples were collected from Grids I-4, H-5, J-5, and K-5 on July 2nd.
* Waste characterization samples were collected on July 1st (samples are collected approximately every 1,000 cubic yards).
* Water treatment system samples were collected on June 30th and July 2nd.
Analytical Data:
* Results from water treatment samples collected on June 26th and June 30th were below the laboratory detection limit of 0.63 ug/L.
* Results from confirmation sampling of Grid K-6 indicated that PCB concentrations remaining in the base of the excavation and the south sidewall ranged from 0.0025 to 0.3 mg/kg, which is well below the cleanup goal of 11 mg/kg. However, the two samples collected on the north sidewall exceeded the cleanup goal. PCB concentrations were 2,100 and 53 mg/kg.
No Site work occurred during July 4-6 in observance of the Independence Day holiday.
RPM Samantha Urquhart-Foster will provide oversight during the next reporting period, July 7-13, 2008. Activities planned for the next reporting period include:
* Continue excavation/transport of > 50 mg/kg material from grid I-6W to the engineered stockpile.
* Decontamination of equipment and subsequent wipe sampling.
* Begin removal of overburden from I-6E and I-8, as well as areas overlying > 50 mg/kg beyond the original grid limits (based on confirmation sample analytical results).
* Continue waste characterization sampling/analysis.
* Continue confirmation sampling/analysis of grids following waste removal.
* Continue pumping/treatment/sampling/analysis of water from Cell No. 2 (sampling to be performed on July 7th and July 10th).
* Possibly begin construction of a second engineered stockpile.
Removal activities have conducted according to schedule, with a few weather delays. However, the schedule has been extended. The schedule has been revised to change the demobilization date to August 28, 2008. The schedule extension is primarily due to:
* required removal of additional material
* rain delays
* construction/repair of access road to the engineered stockpile
* deconstruction and reconstruction of a decon pad on the Holtrachem site
* construction of a second engineered stockpile to accommodate the increased volume of WWTS containing PCBs at concentrations exceeding 50 mg/kg.
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