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 10-16, 2008, with Samantha Urquhart-Foster, RPM, coordinating from the office, as well as attending the pre-final walk-through on November 10, 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:
* Continued excavation/transportation of material with PCB Aroclor 1268 concentrations greater than 50 mg/kg. On November 11, 2008, approximately 204 cubic yards of soil was transported from the pipe trench to the Engineered Stockpile (ES) #2.
[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 13,020 cubic yards.]
Dewatering Activities:
* Rain fell on the Site on three days during this reporting period, the amounts ranging from 0.03 to 1.84 inches per day.
* During this reporting period, 181,900 gallons of water was treated and discharged to IP.
* The total volume of water treated since treatment operations began on June 18, 2008 is approximately 4,608,400 gallons.
Sampling Activities:
* Collected water treatment samples.
* Continued collecting cell-wide confirmation samples on grid nodes.
* 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 1,300 mg/kg. The PRPs are attempting to achieve remediation levels of less than 1 mg/kg. Two samples had concentrations exceeding 1 mg/kg, both were from the pipe trench (1.8 mg/kg base of trench segment 5, 1300 mg/kg sidewall of trench segment 5).
* Material management sample results were received from the sediment in the water treatment settling ponds. Results were 54 mg/kg and 46 mg/kg. After water treatment operations cease, the material will be transported to ES#2.
* Wipe sample analytical results were received from four pieces of heavy equipment that had been decontaminated. All results were below the decontamination goal of less than 10 ug/wipe.
* Water treatment data from samples collected on 11/10 and 11/12, indicated effluent results as <0.63 ug/L and 0.042J ug/L, respectively. (The treatment goal is <3 ug/L.)
On November 10, 2008, a pre-final walk-through inspection occurred at the Site. Participants included: Samantha Urquhart-Foster (EPA, RPM), David Mattison (NCDENR), Prashant Gupta (Honeywell), Ed Kreul (IP), Conan Fitzgerald (URS), Dave Crawford (URS), Denis Ewing (CH2M Hill), Keri Hallberg (CH2M Hill), Robert Custance (CH2M Hill), Joe Hambrick (CH2M Hill), Robert Evans (Shamrock), Henry Havener (Shamrock), and Acie Croom (OMI). A few minor punch-list items were identified for the Engineered Stockpiles. CH2M Hill will prepare a memo documenting the results of the inspection.
Activities planned for the next reporting period include:
* Upon receipt of confirmation sampling results, determine if further excavation/transport of material from Cell No. 2 is necessary
* Continue pumping water from Cell No. 2 through the treatment system. Depending on sump water table, influent samples will be collected.
* Backfill pipe trench with approved material from Navassa Sand Pit.
* Decontamination of select equipment.
* Demobilization activities will begin upon receipt of final confirmation sample results indicating <1 mg/kg.
The revised schedule for the completion of the removal activities indicates demobilization on December 5, 2008. However, the demobilization date is highly dependent upon sample results.
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