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.
RPM Samantha Urquhart-Foster provided oversight of removal activities during this reporting period from the office (September 15 - 21, 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:
* Completed liner installation for the expansion of Engineered Stockpile #2 (ES#2). QA/QC results were submitted to the team and approved.
* Began construction of additional access ramps for ES#2.
Excavation Activities:
* Because of liner expansion occurring on ES#2, excavation was limited to material with PCB Aroclor 1268 concentrations less than 50 mg/kg. During September 15-19, 2008, approximately 2,568 cubic yards of soil was transported from IP Cell #2 to IP's landfill. This material orginated from Grids I-12, K-8, K-12, M-8, M-14, and O-8. On September 15th, 300 cubic yards of material was excavated from Grid O-6 and was staged in a temporary stockpile.
[Note: Both ES #1 and ES #2 are currently at capacity. No additional material can be moved from IP to HoltraChem until the expansion of ES#2 is complete. ES #1 is estimated to contain 8,000 cubic yards and ES #2 is estimated to contain 9,000 cubic yards. It is currently estimated that an additional 6,000 cubic yards remains to be excavated and placed in ES #2.]
Dewatering Activities:
* No rain was reported during this reporting period.
* During September 15-21, approximately 130,200 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 3,575,600 gallons.
Sampling Activities:
* Water treatment system samples were collected on September 15th and 18th.
* No "material management", confirmation, nor waste characterization samples were collected this week.
Analytical Data received during the reporting period:
* Water treatment data from samples collected on 9/11 were undetected for Aroclor 1268 with a maximum detection limit of 0.096 ug/L. (The treatment goal is <3 ug/L.)
* Confirmation data from samples collected on 9/11 were received during this reporting period. The results are as follows: Grid G-4 base (6.8 mg/kg), G-4 north wall (0.15 mg/kg), G-5 base (30 mg/kg), G-5 north wall (0.82 mg/kg), H-4 base (27 mg/kg), H-4 north wall (0.2 mg/kg), H-4 south wall (0.084 mg/kg), M-5 base (0.067 mg/kg). The bases of grids G-5 and H-4 will require additional excavation to achieve the cleanup goal of 11 mg/kg.
NCDENR representative Dave Mattison will provide oversight during the next reporting period, September 22-28, 2008, with RPM Samantha Urquhart-Foster will provide oversight from the office. Activities planned for the next reporting period include:
* Continue water treatment system operations.
* Collect water treatment system samples.
* Begin hauling >50 mg/kg material to the expanded ES#2.
* Continue mixing/hauling <50 mg/kg material from the southeast corner of Cell #2 to IP's landfill
* Continue excavation activities pending analytical results
* Collect material management samples from excavated material in ES#2.
The schedule for the completion of the removal activities was extended once again. The revised schedule indicates the demobilization date shifted from October 3rd to October 21, 2008. The schedule may be extended further if there are numerous rain delays or more contaminated material is discovered than is currently anticipated.
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