(This photograph is of the trench excavated along the pipe line which runs from HoltraChem to International Paper (IP). The black 4"-diameter HDPE pipe in the center of the trench in this photograph historically transported waste water, which resulted in the deposition of Aroclor 1268 in IP's waste water treatment pond (currently known as Cell #2.)
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 from the office during this reporting period (August 25 - 31, 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 August 25-26, 2008, approximately 456 cubic yards of soil scraped from the bottom of grids was transported from IP cell #2 to IP's landfill. This material orginated in Grids H-5, M-5W, J-5, and K-5.
* During August 28-29, 2008, the pipe which was historically used to transport waste water from HoltraChem to the IP lagoon was excavated and removed.
[Note: Both Engineered Stockpile #1 (ES #1) and Engineered Stockpile #2 (ES #2) are 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 3,000 cubic yards remains to be excavated and placed in ES #2. The silt fence surrounding ES #2 was relocated during this reporting period to begin construction activities.]
Dewatering Activities:
* Rain fell on the Site on four days during this reporting period with measurements ranging from 0.01 to 3.01 inches per day. The heaviest rain day was August 27, 2008.
* During August 25-31, approximately 156,400 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 2,840,400 gallons.
Sampling Activities:
* Water treatment system samples were collected on August 25th and 28th. All results were below the treatment goal of 3 ug/L.
* Material Management samples were collected on August 21st and data was received during this reporting period. The samples collected from the temporary stockpile of material excavated from the northeast quadrant of grid G-8 had results of 28 mg/kg of Aroclor 1268. This material will be transferred to IP's landfill.
* Confirmation samples were collected from several grids this week.
* Waste characterization samples were collected as planned (samples are collected approximately every 1,000 cubic yards).
RPM Samantha Urquhart-Foster will provide oversight during the next reporting period, September 1-7, 2008. Activities planned for the next reporting period include:
* Continue water treatment system operations and monitoring of pumping activities. Collect water treatment system samples.
* Anchor Engineered Stockpile #1 bottom liner to the cell pit. Complete final QA/QC inspection and make any repairs if required.
* Continue/complete 1 foot bottom scrapes of designated grids in Cell #2 for transport to IP Landfill.
* Collect confirmation samples from bottom scraped grids.
* Transport material from Grid G-8NE to IP Landfill in accordance with sample results.
* Begin construction of additional storage area for Engineered Stockpile #2.
* Backfill access road from pipe excavation pending analytical results.
* Prepare for projected landfall of Tropical Storm/Hurricane Hanna on September 5-6.
Removal activities are still scheduled to be completed by September 24, 2008. However, Tropical Storm/Hurricane Hanna is currently projected to impact coastal North Carolina. The schedule may be revised after impact from Hanna has been assessed.
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