Passive soil gas investigations are performed to provide a preliminary indication of the presence and location of contaminated soil and groundwater at sites where volatile and semi-volatile compounds such as petroleum fuels, solvents, and explosives have been released. These surveys are currently required by the  Ministry for the Protection of the Environment at gas station sites prior the initiation of a soil investigation.

ADAMA currently performs these survey’s using samplers and analytical laboratories in the U.S. such as Beacon, and Gore. The compounds list analyzed includes a wide range of volatile and semi-volatile compounds, chlorinated organic compounds (PCE, TCE, and DCE), petroleum compounds (BTEX, MTBE, TPH, and PAH’s), and explosives (TNT).

These surveys require installation of an absorbent canister into the soil by drilling small diameter borings (2.5 cm) to a depth of 1 the 4 meters. The canisters are left in the ground for a period of 2 weeks and then collected and submitted to the laboratory for analysis.

Active soil gas investigation are performed at sites where quantitative data is required for soil gas concentrations. This data can then be compared to published threshold values to determine if soil gas contamination is present.

ADAMA has conducted over 30 of these surveys at industrial and commercial sites where exposure to soil gas is suspected from petroleum (BTEX, MTBE and Naphthalene) or organic solvent contamination (such as TCE, PCE, DCE and Vinyl Chloride). ADAMA is certified by the Israel Laboratory Accreditation Authority (ISRAC) for the performance of these surveys. Active soil gas surveys require the installations of a soil gas piezometer having a diameter ranging from 2.5 to 5 cm. These piezometers can be installed using a drill rig or using hand operated equipment such the AMS Soil Gas sampling (www.ams-samplers.com/category.cfm?CNum=3). The soil gas is extracted from the piezometer at a specified depth and the soil gas sampled using a Summa Canister (typically 6 liters) and the sample analyzed for a list of volatile organic compounds using EPA Method TO-15 analysis.

ADAMA personnel have implemented the remediation of groundwater using oxygen release compounds containing magnesium peroxide or calcium peroxide at sites in the United States and in Israel. At theses sites, the slow release of oxygen to the groundwater promotes the aerobic biodegradation of organic contaminants such as BTEX, MTBE and Naphthalene found in petroleum products.

These compounds are supplied by distributors in the United States such as Regenesis which markets a compound called ORC (www.regenesis.com/contaminated-site-remediation-products/enhanced-aerobic-bioremediation/orc/) and PermeOx Ultra manufactured and distributed by PeroxyChem (www.peroxychem.com/markets/environment/soil-and-groundwater)

ADAMA has implemented the in-situ remediation of soil using Bioventing, SVE and/or Air Sparging at over 20 sites throughout Israel. Bioventing is a technology which promotes the biological degradation of organic compounds by aerating the subsurface unsaturated zone soils. Bioventing differs from Soil Vapor Extraction (SVE) in that bioventing is generally implemented through the injection of air into the subsurface and SVE relies on the extraction of air and volatilization of contaminants.

These technologies are typically implemented in multiple phases which include a pilot study, design, equipment procurement, construction and system operation and monitoring. ADAMA provides the expertise and engineering to implement all of these phases in a cost effective and efficient manner.  Our pilot studies are performed by experienced professional with over 30 years of experience in this field and the designs are performed by experienced engineers.

Passive SVE and Bioventing is an economical alternative for the remediation of soils contaminated with volatile organic compounds including petroleum compounds (BTEX, MTBE and Naphthalene) and Chlorinated Compounds such as PCE, TCE and DCE. This technology is similar to active SVE and Bioventing but relies on the natural differences in the barometric pressure between the subsurface soils and the atmosphere to either inject or extract air. A specially engineer cap is placed on the well head which closes and opens based on the changes in the barometric pressure. Since a blower or compressor is not required, the only capital costs are the well and the cap and the system can be adapted to existing monitoring wells to little additional costs.
Air Sparging is a proven technology for the remediation of groundwater contaminated with volatile organic compounds (VOC) such as BTEX, MTBE, TCE, PCE and DCE.  ADAMA has implemented this technology at muttiple sites in Israel over the past 5 years and approval has been received from the Israel Water Authority. Air Sparging is performed by the injection of air using a compressor or blower into a series of wells screened below the groundwater table. The injected air volatilizes the contamination and promotes biological degradation by the addition of oxygen into the groundwater. This technology is typically combined with SVE to control the discharge of soil vapors from the site.  Similar to SVE and Bioventing, this technology is implemented with a pilot study, design, equipment procurement and operation and monitoring.
Remediation of light non-aqueous phase liquids (LNAPL’s) can be achieved by both passive and active skimmer systems. The primary advantage of these skimmer systems is the removal only of free product which eliminates the necessity to manage and dispose of groundwater extracted from a total fluids pump. The active skimmer systems are powered by compressed air that can be supplied using a small compressor and is controlled by a pneumatic controller. The free product recovered is pumped into a storage tank for disposal. Passive skimmer systems operate similar to active system but do not require compressed air to evacuate the free product.