As of December 31, 2018, approximately 12.9 million gallons of petroleum product has been recovered, and over 5.8 billion gallons of groundwater has been recovered and treated from the three sites comprising the Greenpoint Petroleum Remediation Project. In 2018, the project recovered a total of approximately 79,000 gallons of product, while recovering and treating over 280 million gallons of groundwater to Clean Water Act standards.
ExxonMobil Greenpoint Petroleum Remediation Project (EMGPRP – S224150)
ExxonMobil continues to operate two product and groundwater treatment systems, the on-site recovery and containment system (RCS) located on Kingsland Yard (OU4) and the off-site free-product recovery system (ORS) located at the corner of Bridgewater and Monitor streets (OU7). Typical routine maintenance of both systems includes critical safety device (CSD) checks, acid cleaning of the air strippers, carbon change-outs, filter bag replacement, system inspections, soil vapor extraction (SVE) system sampling, bimonthly discharge monitoring report (DMR) sampling, and weekly operation and maintenance (O&M) task lists.
ExxonMobil completed the installation of a new stormwater drainage piping system on the property in 2018. The new stormwater system includes catch basins, conveyance piping, a hydrodynamic separator, and a filter unit to treat stormwater prior to discharge from the property. ExxonMobil also relocated and enlarged the on-site recovery and containment system (RCS) effluent discharge pipe to enable the outfall to accommodate the current and expected future flow of water from the Kingsland Yard property. The existing 12-inch-diameter outfall pipe is being replaced with a 36-inch-diameter pipe, and an associated vault is being installed to house a check valve and weirs, which will ensure the correct flow direction and velocity of discharge to the creek. ExxonMobil is also making modifications to the bulkhead to ensure a watertight seal between the new pipe and the bulkhead.
In August 2018, NYSDEC approved ExxonMobil to enhance free-product recovery on the Kingsland Yard property by installing a new pressure-pulse waterflooding injection well network to increase the hydraulic gradient and product movement toward recovery wells. Trenching and installation of pumping wells and vaults for the waterflooding program began in August 2018, with the majority of the construction work completed by the end of December 2018. The waterflooding program is expected to begin operation in spring 2019.
In 2017, NYSDEC approved an Interim Remedial Measures Work Plan to delineate and excavate areas where Total Petroleum Hydrocarbon concentrations exceed site-specific cleanup criteria, delineation activities in the North Henry, Monitor, and Kingsland Yards. Excavation activities began in Monitor Yard in December 2017, and work shifted to Kingsland Yard in 2018 once the Monitor Yard work was complete. Petroleum-contaminated soil was temporarily stockpiled on-site before being transported off-site for proper disposal. Contaminated soil removal work was completed in April 2018, with the exception of two excavation areas within Kingsland Yard that were inaccessible as the result of stockpiled clean fill for work being performed in OU-3. The soil removal work in these two remaining areas will be completed in 2019 once they become accessible.
Former Paragon Oil Terminal (S224083) and Apollo Street Creek Parcels (S224122)
Through April 2018, Chevron-Texaco continued to operate a total fluids recovery (TFR) system where 17 recovery wells pumped both groundwater and product into an onsite treatment system that collected the product and treated groundwater before discharging into sanitary. Typical routine maintenance included backwashing the clay and carbon units, changing out spent clay and carbon, and replacing filter bags. Recovery well pumps were pulled and cleaned as needed, typically every six weeks to two months, based on performance metrics.
Chevron-Texaco also operated a vapor-phase recovery (VPR) system to remove vapor contamination from beneath the Empire Merchants’ buildings and aid in the reduction of product accumulations in and around the existing recovery well network. The VPR is a relatively low-vacuum system aimed at volatilizing PSH in extraction wells and reducing the PSH loading into the water treatment system.
Starting in April 2018, both TFR and the VPR systems were shut down to construct system upgrades that were outlined and approved by the NYSDEC. TFR system upgrades include demolition of the existing TFR system buildings and replacement with a new, expanded remediation system that can handle additional flow from new recovery wells with improved telemetry. As of December 31, 2018, work on the system upgrades was still ongoing, with work expected to be complete and both systems operational in early 2019.
As part of the treatment system operation and maintenance, Chevron-Texaco routinely performs bulkhead inspections and maintains the boom containment systems along both the former Paragon Oil Terminal and Apollo Street bulkheads. Chevron-Texaco continued to reseal bulkhead seams with a marine epoxy and adjusting containment boom on a quarterly basis in 2018. One sheen was observed within containment booms along the creek bulkhead during oversight events in 2018, but no sheens were observed outside the containment boom system.
Indoor monitoring wells in the Empire Merchants and the Apollo Street warehouses are inspected monthly, with slab maintenance activities (cracks, seams, and joints are repaired and resealed) are performed twice a year to prevent the possibility of vapor intrusion during the semiannual warehouse shutdowns (January and July). Ambient air quality in the warehouses was monitored on a semi-annual basis during the shutdowns, with a total of 18 air samples collected across the site to ensure air quality inside the building is safe. Product and groundwater sampling were also performed at select indoor monitoring wells during the warehouse shutdown events.
KM Terminal (formerly BP Terminal) (S224082)
In 2018, KM continued the operation of 12 product recovery wells and a groundwater treatment system that was installed in 2014. Typical routine recovery system maintenance activities include system alarm and integrity checks, bag filter changes, adjustments to the chemical feed for iron reduction, acid cleaning of the air stripper, and cleaning the product pump intake screens.
In 2017, KM began a program to modify recovery well pumps to run using an on-site air compressor to supply air, which require less maintenance and more continuous operation time for the recovery well pumps than the previously used nitrogen gas tanks. KM completed all the recovery wells compressed air conversion process in June 2018.
Due to persistent LNAPL thicknesses greater than 3 feet in monitoring wells OW-11 and MW-6, both wells were outfitted with a temporary product recovery system that operates independently of the full-scale recovery system. Due to consistent product recovery from MW-6 over the past 3+ years, the temporary liquid petroleum hydrocarbon recovery equipment was removed from the well in 2018 so the monitoring well could be converted into a permanent recovery well in 2019.
KM continued to perform weekly methane screening at various locations on the Terminal Property and performed an annual site-wide vapor screening event to monitor the levels of methane, oxygen, carbon dioxide, carbon monoxide, hydrogen sulfide, balance, lower explosive limit, barometric pressure, and relative pressure across the site. No vapor readings were identified by the screening events that required further action in 2018.
KM began the process of developing an Alternatives Analysis Report in 2018 that will evaluate remedial alternatives to address any potential significant threats to the public health from the remaining contamination at the site. This report will summarize previous and current site conditions, the current remediation activities, and remedial goals for the site while taking into taken into consideration the current and future use of the site. Following an examination of potential remedial technologies to for each media at the site (groundwater, soil, and air), the report will identify the recommended remedial action for the site going forward. It is expected this report will be completed by the end of 2019.