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.
RPM Samantha Urquhart-Foster provided oversight of removal activities during this reporting period (June 16-22, 2008). IP's 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 16-20, 2008, approximately 2,058 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 M-6 and K-6.
• Approximately 70 cubic yards of overburden material from Grid M-10 were used to repair the engineering stockpile entrance ramp.
Dewatering Activities:
• During June 18-21, approximately 229,300 gallons of water from Cell #2 was pumped, treated, and discharged to IP.
Sampling Activities:
• Confirmation samples were collected from Grid M-6 on June 17th. Two of the twelve samples collected from the grid's base and sidewalls exceeded the clean-up goal.
• Water treatment samples were collected on June 16, 18, 19, 20, and 21. The majority of the results were below the detection limit of 0.63 ug/L. The few detections were well below the treatment goal.
• Samples were collected from the engineered stockpile on June 17th and 19th. Results are pending.
RPM Samantha Urquhart-Foster will provide oversight during the next reporting period, June 23-29, 2008. Activities planned for the next reporting period include:
• Continue excavation of the > 50 mg/kg PCB material, transportation and placement of the materials into the engineered stockpile.
• Continue confirmation sampling of the grids (post excavation).
• Continue pumping/treating/sampling/analysis of water from Cell #2.
Removal activities have conducted according to schedule, however, the schedule has been extended. One and a half days were lost this week due to rain impacts. Other factors that were used in extending the schedule include mixing with fly ash slows production time, and contamination in Grid M-6 (and potentially others) extends farther than originally anticipated. The schedule has been revised to change the completion date from July 30th to August 11, 2008.
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