(This photograph is of the Engineered Stockpile #2 immediately after Tropical Storm Hanna affected the Site. Some of the temporary cover was blown off the stockpile by 40 mile per hour winds.)
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 (September 1 - 7, 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 focused on preparation for hurricane/tropical storm Hanna.
The following items were completed on the IP property:
* Constructed a berm around the western portion of remaining material to divert water to the treatment area
* Constructed a silt fence around the remaining >50 mg/kg material
* Backfilled pipe excavation with material from Grid M-10
* Pumped down the water treatment settling ponds
* Removed potential projectiles and stored in the conex box
* Secured chemical totes and pumps
* Completed activities and checklists in Hurricane Preparedness Plan
The following items were completed on the Holtrachem property:
* Sandbags were placed on top of the engineered stockpile liners
* Completed activities and checklists in Hurricane Preparedness Plan
Tropical Storm Hanna affected the Site on Friday and Saturday of this reporting period. The plant manager contacted RPM, Samantha Urquhart-Foster, on Saturday morning to provide storm impact assessment information. The storm deposited 2.7 inches of rain. The temporary cover of Engineered Stockpile #2 (ES#2) was blown off in some locations, however, no releases from the Site were observed. Some clean berm sandy/soils were washed down to the silt fence, but there were no signs of material from the stockpile migrating. RPM relayed the information to OSCs Ken Rhame and Leo Francendese.
Excavation Activities:
* Because of hurricane/tropical storm preparations, limited excavation activities occurred. On September 2, 2008, approximately 372 cubic yards of soil was transported from IP cell #2 to IP's landfill. This material orginated in Grid G-8NE.
[Note: Both Engineered Stockpile #1 (ES #1) and 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 6,000 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 three days during this reporting period with measurements ranging from 0.02 to 2.7 inches per day. The heaviest rain day was Friday, September 6, 2008, as a result of tropical storm Hanna.
* During September 1-7, approximately 203,400 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 3,043,800 gallons.
Sampling Activities:
* Water treatment system samples were collected on September 2nd and 4th. All results were below the treatment goal of 3 ug/L.
* Material Management samples were collected on September 2nd and data was received during this reporting period. The samples collected from overburden above the pipe had results raning from 4.1 mg/kg to 31 mg/kg of Aroclor 1268. This material will be transferred to IP's landfill.
* Analytical data from confirmation samples that were collected from several grids and the pipe trench last week was received. Results ranged from 0.030 mg/kg to 140 mg/kg of Aroclor 1268. The bottom of Grid H-5 and several locations within the pipe trench will require additional excavation.
* No waste characterization samples were collected during this reporting period due to no material being moved to ES#2 (one sample is collected per every 1,000 cubic yards of material brought to an engineered stockpile).
RPM Samantha Urquhart-Foster will provide oversight during the next reporting period, September 8-14, 2008. BRIDGE Intern Tara Houda will accompany her. Honeywell project manager Prashant Gupta will also be visiting the Site. Activities planned for the next reporting period include:
* Continue water treatment system operations and monitoring of pumping activities. Collect water treatment system samples.
* Repair tears in bottom flap of the liner on ES#1.
* Install additional bottom liner along the edges of ES#2 to enlarge capacity.
* Continue 1-foot bottom scrapes of designated grids in Cell #2 for transport to IP Landfill.
* Collect confirmation samples from bottom scraped grids.
* Begin hauling <50 material from SE corner of cell #2
* Begin hauling >50 material to additional stockpile area in engineered stockpile #2
The schedule for the completion of the removal activities was extended because of days lost in preparation for hurricane/tropical storm Hanna and the storm itself. The revised schedule indicates the demobilization date shifted from September 24th to October 1, 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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