Field Solutions

Direct Push | Soil Vapor | Soil | Ground Water

Direct Push Sampling Services

Direct Push sampling is the most cost-effective and technically diverse, EPA endorsed, method of acquiring a variety of environmental samples. Rigs can use drive rod ranging from 1" to more than 3" in diameter, and can employ tools for sampling of vapors, soils, and ground water and generating geophysical data from unconsolidated formations. All of the rigs have been used for setting monitoring wells and for in situ remediation.

ESN operates the most powerful and diverse fleet of Direct Push probe rigs in the U.S. Three classes of Direct Push rigs are operated: Heavy duty, medium duty, and limited access. ESN Rocky Mountain has in its fleet one Geoprobe DT6610, one AMS 9600 Power Probe (both with auger capability), two Thunderprobes, a track mounted Geoprobe 54DT, two truck-mounted probes, and two limited access probes (one on an ATV and the other on skids), plus hand probes and Little Beaver augers.

Geoprobe® 6610DT
The 6610DT is Geoprobe’s most powerful and diverse direct push rig. The rig produces more than 35,000# of down force and 47,000# of pullback power, and is augmented by the GH60 hydraulic hammer. It is mounted on a diesel powered, rubber-tracked vehicle weighing about 7000#. The footprint is about 4’ x 8’, allowing access to virtually anyplace. It can even be operated indoors. Our unit also is equipped with the GA3000 auger system, and is capable of turning both solid and hollow stem augers for breaking through difficult lithologies and setting 2” wells easily. The rig uses 5’ rod, including up to 3.25” drivable casing. The rig has installed vapor and water monitoring wells as deep as 138 feet in the Rocky Mountain area.

Power ProbeTM
The Power Probe 9600 Pro Series Titan (manufactured by AMS) is the largest and most powerful truck mounted Direct Push rig available from AMS. It is mounted on a 2-ton capacity truck. The rig has nearly 17,000 lbs. of static weight and up to 33,000 pounds of down force, combined with 41,000 lbs. of pull back power. It is equipped with a 350 ft-lb hydraulic hammer, driving 5-foot rods and tools. It can push 3.25" diameter probe rod and install up to 2" diameter PVC or Prepacked Screens. In addition, it is equipped with a 3,500 ft-lb auger head and can turn 4.25" ID hollow stem augers for installation of 2" wells and injection points. The rig can sample soil, soil gas, and ground water to 100 feet and more in unconsolidated sediments, plus lightly consolidated sediments and weathered bedrock.

ThunderprobeTM
The Thunderprobe is a powerful hydraulic direct push unit equipped with a large vibratory hammer mounted on a 1.5-ton truck. The direct push hydraulic unit consists of a rear-mounted, dual ram configuration mounted in conjunction with a vibrating component capable of producing high-frequency impact energy. An 8,000-pound static reaction weight (at probe point) and 30,000-pound pullback capacity provide ample force to overcome most common geologic conditions. The low profile mast is twelve feet high when fully extended and the framework is articulated to allow for a full range of positioning, including up to a 20º angle for boring underneath structures.

The Thunderprobe can sample soil, soil vapor, and ground water; and can install small diameter wells in generally unconsolidated sediments at depths approaching 100 feet, depending on lithology. The rig uses 1.5" to 2.0" probe rod. The rig cannot drill bedrock formations, but can penetrate some weathered formations.

Track-Mounted Geoprobe
ESN’s DT-54 is a highly flexible rig with enough power to complete all but the hardest jobs, but the ability to maneuver in tight spots and rough terrain. It has run virtually all tools, including the 3.25” Dual Tube, and can set wells, collect soil and water and vapor samples in most conditions. It has tested soils and ground water to more than 70 feet in depth.

Truck-Mounted Geoprobe
For less strenuous duty, ESN can employ its Truck Mounted Geoprobe. Placed on a ¾ ton, F250 Ford four-wheel drive pickup truck, this Probe is capable of operating at depths exceeding 50 feet, in a variety of terrains. As with all our sampling equipment, it is stocked with a full variety of sampling equipment and supplies to acquire soil, ground water and soil gas samples. Additionally, this probe can install a variety of small diameter monitoring equipment in the subsurface.

Dolly-Geoprobe
ESN has constructed a small footprint, indoor Geoprobe on a dolly. With a 24" x 24" base, lightweight, and two wheels, it can be used in almost any tight space. It is equipped with a stand-alone power supply or can be connected to any of ESN’s other rigs at a distance of up to 150 feet. Concrete expansion bolts are used to secure the probe to the floor. It has been used as deep as 35' and can collect soil, water, and soil vapor samples. It has also been used horizontally, mounted to retaining walls or basement walls, for sampling and for installation of injectors for in situ remediation.

ATV-Geoprobe
ESN operates the first ATV-Geoprobe sampling system devised in the world. This sampling system significantly improves the collection of environmental samples for the most severe of terrain conditions or for indoors with very low overhead or space available. The system combines the speed of hydraulic, probe-driving machinery (an average of 20 to 40 samples per day) with the versatility of a small, four wheel, all-terrain vehicle. The ATV-Geoprobe can reach depths to 30 feet (and more), and can sample soil, groundwater and soil gas.
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Soil Vapor (Gas) Sampling

Soil vapor is sampled for a variety of purposes, ranging from early stage reconnaissance to risk assessment and remediation monitoring. ESN has more experience than all other soil gas providers in the Region combined. As a result, ESN can apply exactly the right tool to meet the project’s technical and budgetary needs. With the rigs and tools available to ESN, the most appropriate sample can be taken in virtually any situation, with proper Quality Control. Numerous practitioners improperly apply methods or exercise insufficient field QC.

Reconnaissance Site Assessment
Active (probe) sampling is conducted by ESN, coupled with on-site analysis of VOCs for fuels, solvents, fixed gases and natural attenuation compounds, and other compounds. Real time analysis assures that samples are taken ONLY where necessary, allowing full characterization and quantitation without unnecessary sampling and analysis. Samples can be taken as deep as 80 feet, allowing 3-Dimensional displays, identification of source areas, mapping of vapor plumes (from major vapor sources), and observation of contaminated ground water.

Landfill Testing
ESN has conducted more than a hundred landfill assessments, including methane leak testing and mapping, Tier II NMOC testing, non-methane vapor risk evaluations, lateral vapor transport projects and others. ESN applies both Method 25C and other methods of sampling to the acquisition of gas samples as large as 6L in Tedlar bags, Summa Canisters, evacuated containers, and on sorbents.

Vapor Intrusion Risk (Indoor Air) Assessments
Risk Based Corrective Action (RBCA) has made the importance of the vapor migration pathway greater than previously recognized. Contaminated soils and ground water, left in place for either Natural Attenuation or in situ remediation, or as part of Brownfields investigations, offer an additional pathway to potential receptors—vapor migrating into buildings. Under ideal conditions, the indoor air concentrations of such compounds as benzene, vinyl chloride, or DCE can significantly exceed the levels allowed by EPA and the States that regulate such exposures. Because vapor transport models (e.g., Johnson- Ettinger) calculation procedures can either understate or overstate the risk from source to building by up to 2 orders of magnitude, based on ground water data, the actual sampling of soil gas in a vertical profile can easily document the true potential risk to surface occupants.

ESN’s sampling and analytical methods meet or exceed both EPA and state guidelines. The soil gas technology accurately collects a large volume of stabilized vapor samples and for analysis on-site or off-site. Unlike most conventional methods, the ESN method will provide sensitivity down to <1 ppbv in vapor.

Remediation Vadose Zone Monitoring
Remediation programs often alter adjacent vapors or create vapors that are highly indicative, even quantitatively, of the cleanup progress—for example, vapor extractions, bioventing, natural attenuation, reactive barriers, etc. In addition, the remediation of vapor plumes that either contaminate ground water or get into buildings can be monitored directly. By sampling and analyzing for the appropriate type of compounds, vapor monitoring can be an inexpensive and quick method to document the progress of site cleanup.

ESN installs and monitors permanent and temporary vapor points as deep as 80 feet below grade, in single and multi-point nested wells. Analysis is available both on-site and offsite.
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Soil Sampling

ESN samples soil as deep as 100+ feet below grade, either continuously or at specified intervals. Soil samples can be given either to on-site or off-site labs for analysis. As always, ESN Direct Push operations can yield virtually no cuttings needing expensive IDW analysis and storage, significantly reducing costs.

ESN’s methods allow both chemical and lithologic characterization, and are applicable to any type of site assessment. In many cases, samples taken by ESN have been tested for engineering properties (density, porosity, permeability, etc.) to obtain data for remediation design or risk assessment modeling.

Sub-Water Table Sampling
Soil sampling can be conducted both in the vadose zone and in the saturated zone. Cased-hole coring tools allow acquisition of soils below water table, without cross contamination, clear into the upper reaches of bedrock, in order to characterize the vertical distribution of chemical contaminants. This is vital information for remediation design, especially for DNAPLs, at which ESN has considerable experience.
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Ground Water Sampling

Ground water sampling to track contaminant plumes using Direct Push has the advantage of generating essentially no cuttings and frequently involves little or no purging. ESN has taken ground water samples from as deep as 120 feet, using peristaltic pumps or bailers. Waterra pumps and bladder pumps are also used. In addition to obtaining water table samples, ESN can acquire vertical profiles of ground water.

Vertical Profiling of Aquifers
Vertical profiling is essential to characterizing the distribution of dense organic compounds, whether in dissolved or DNAPL form. Using either a driveable casing system (allowing either or both soil and water sampling at discrete intervals) or a vertical water profiler (e.g., Waterloo or Geoprobe profiler) or nested wells or probes (discrete samplers) installed using ESN’s Direct Push rigs, vertical sampling dramatically enhances the quality and usefulness of ground water data.

Temporary and Permanent Wells
ESN installs and samples the widest variety of small-bore temporary (piezometer) and permanent wells, as deep as 100 feet in unconsolidated sediments. Two different styles are employed: small bore (0.5" to 2" screen and riser) PVC or steel installations using traditional or modified well construction methods; and “PrePacked” wells with PVC or steel risers.

Pre-Packed Well Systems
Pre-Packed well systems are available in sizes ranging from ½" bore to 2" bore. They are constructed in custom lengths and with varying screen and sand sizes. The use of these methods insures a fully completed well, with effective sand pack along the entire screen length. In addition, pre-packed bentonite seal packs are also available for the same bore size ranges for completion below water table, affording discrete depth sampling for aquifer profiling in permanent wells.
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