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 was 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 was 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.
David Mattison, NCDENR, provided oversight of removal activities during this reporting period, November 3-9, 2008, with Samantha Urquhart-Foster, RPM, coordinating from the office.
* 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:
* Continued excavation/transportation of material with PCB Aroclor 1268 concentrations greater than 50 mg/kg. On November 7, 2008, approximately 168 cubic yards of soil was transported from grid I-6SW to the Engineered Stockpile (ES) #2.
* Continued excavation/transportation of material with PCB Aroclor 1268 concentrations less than 50 mg/kg. During November 3-8, 2008, approximately 2,244 cubic yards of soil was transported from IP Cell #2 to IP's landfill. This material orginated from Grids C-6, G-5, G-6E, G-6W, I-12, M-8, M-12, M-14, and U-12.
[Note: ES #1 is at capacity with approximately 8,000 cubic yards of material. The top and bottom liners have been seamed together. As of the end of this reporting period, ES #2 is estimated to contain 12,816 cubic yards.]
Decontamination Activities:
* Decontaminated four pieces of heavy equipment using the revised decontamination protocol.
Dewatering Activities:
* Rain fell on the Site on two days during this reporting period, the amounts ranging from 0.06 to 0.8 inches per day.
* During this reporting period, the water treatment system was modified by placing the third carbon unit online. Water was circulated through the system for a short period of time in order to collect a sample to verify the effectiveness of the modification. No water was discharged during this reporting period.
* The total volume of water treated since treatment operations began on June 18, 2008 is approximately 4,426,500 gallons.
Sampling Activities:
* Collected confirmation and water treatment samples.
* Continued collecting cell-wide confirmation samples on grid nodes for lab analysis.
* Collected wipe samples from decontaminated equipment.
Analytical Data received during the reporting period:
* Confirmation sample data from numerous grids and grid nodes were received during this reporting period. Results ranged from undetected to 1.7 mg/kg. The PRPs are attempting to achieve remediation levels of less than 1 mg/kg. Three samples had concentrations exceeding 1 mg/kg, and all three were 1.7 mg/kg (grids: C-6N wall, G-5W wall, and G-6E base).
* Water treatment data from samples collected on 11/3, after system modifications, indicated effluent results as 0.19 ug/L. (The treatment goal is <3 ug/L.)
David Mattison, NCDENR, will provide oversight of removal activities during the next reporting period, November 10-16, 2008. Activities planned for the next reporting period include:
* Conduct the pre-final inspection on November 10th. Attendees to include EPA, NCDENR, Honeywell, IP, CH2M Hill, and Shamrock representatives.
* Continue water treatment system operations and monitoring of pumping activities. Collection of samples will depend on water table in sump area.
* Upon receipt of confirmation sampling results, determine if further excavation/transport of < 50 mg/kg material to IP Landfill is needed.
* Upon receipt of confirmation sampling results, determine if further excavation/transport of > 50 mg/kg material to engineered stockpile #2 is needed.
* Demobilization activities will begin upon receipt of confirmation sample results indicating all areas have PCB Aroclor 1268 concentrations below the cleanup goal.
The schedule for the completion of the removal activities indicates demobilization on November 20, 2008. However, the demobilization date is highly dependent upon sample results from bottom scrapes and the pipe trench, as well as efforts required for decontamination of equipment.
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