BOS 200+® Technology Application at Active Bulk Storage Facility: A Five Year Review

The subject facility is an active pipeline and petroleum storage site in the Gulf Coast Region where a leaking aboveground storage tank (AST) created a large dissolved and LNAPL plume. BOS 200+®, a modified version of BOS 200®, was applied over a large area during a 6-month period in 2017. Results to date indicate that LNAPL levels have been eliminated or significantly reduced. In addition, benzene and TPH levels have decreased an average of 96.3% and 97%, respectively. A No Further Action determination has been requested and is pending.


Key Dates
• February 2017 – Remedial Design Characterization (RDC)
• Summer/Fall 2017 – Injection of BOS 200+®
• No Further Action (NFA) Determination: Pending
Treatment Area: 93,000 ft2
Lithology: Varied across the large area but consisted mainly of silty clay to clay over weathered shale with some sand and gravel.
Depth to Water: 5 to 25 ft bgs (variable)
Contaminants: LNAPL and TPH
Implementation Method: Direct push and Pre-Drill injection

The challenges for this project included the following: active petroleum storage, pipelines and sub-surface electrical, shallow groundwater table (western treatment area), and shallow DPT refusal in one area, which required a Pre-Drill injection technique.

Principal Objective: Elimination of measurable LNAPL.

1,110 soil samples were collected as part of a large RDC in early 2017. The sample results were used to create an optimized and surgical BOS 200+® design. All samples were analyzed at the RPI Project Support Laboratory at no cost.

Injection specifications:
• 93,000 ft2 Treatment Area
• >1,000 Injection Locations
• 361,000 lbs BOS 200+®

The majority of the injection locations were completed using direct push injection techniques. In one area, shallow refusal was encountered (weathered shale), so the Pre-Drill technique was used to reach the target treatment depth

RESULTS (5 Years Post Application)
• The total number of wells with measurable LNAPL prior to remediation: 15

Post-remediation LNAPL statistics
• No measurable LNAPL: 12
• Sheen: 2
• Measurable LNAPL: 1 (current max LNAPL thickess = 0.02 ft)

Dissolved Total Volatile Petroleum Hydrocarbons
• The average dissolved TPH concentration in the monitoring wells prior to remediation: 20.9 mg/L
• Post-remediation average concentration: 0.38 mg/L (97% reduction)

Post treatment analytical support provided by the RPI Project Support Laboratory at no cost.

Figure 1.
Example of Post Injection Recovery Well Groundwater Data

Download the Project SummaryMore About Bos 200+®