Site Assessment and Remediation

Blue Rock provides the following key professional services related to soil and groundwater contamination:

Phase I and II Site Assessments

Blue Rock also serves clients during property transactions or refinancing by performing Phase I or Phase II site assessments.  Phase I work is conducted in strict accordance with ASTM guidance document E1527-05.  Phase I investigations are aimed at identifying potential recognized environmental conditions at the site or adjacent sites.  This is accomplished by review of environmental government databases, historical use evaluation, aerial photographs, fire insurance maps, site inspection, owner/tenant interviews, and title searches.  If information obtained during the Phase I suggests a potential recognized condition, Blue Rock may recommend a Phase II subsurface investigation.  Phase II activities are similar in nature to the Soil and Groundwater Investigations described in the section above, and they focus on evaluating only the potential recognized environmental condition and nothing else. 

Soil and Groundwater Investigations

Blue Rock professionals have performed and supervised a wide variety of subsurface investigations.  Our staff is adept at designing economically feasible investigation strategies that meet project goals.  For subsurface investigation, a myriad of techniques are available such as (1) passive soil gas surveys, (2) traditional drilling and soil sampling, (3) cone penetrometer tests & electric logging, and (4) geophysical surveys (ground penetrating radar & magnetometers).  Blue Rock endeavors to find ways to increase value of all investigation and monitoring activities, so that project costs can be reduced or redirected onto clean-up activities. 

The goal of site investigation is to define the basic site parameters that will affect the selection of a remedial approach.  These basic site conditions include contaminant type, contaminant distribution/magnitude, contaminant migration pathways, hydrogeological conditions, and potential sensitive receptors. 

Feasibility Studies and Remediation

After the site is characterized, Blue Rock evaluates a wide array of remedial options in order to select an approach that has the greatest technical promise and is also cost-effective.  Core remedial services at which Blue Rock specializes include: 

Soil Vapor Extraction & Treatment

This technology is a tried and true approach at removing volatile contaminants from the subsurface.  It is leverages the physical properties of volatile contaminants to remediate the site.  Blue Rock typically uses SVE to remove gasoline contamination from the vadose zone, and to reduce free-phase gasoline floating on the water table.  This is accomplished by applying a vacuum to wells, which in turn induces air flow through the soil column.  The contaminants volatilize into the air stream, which are then extracted and treated at the surface.  Blue Rock typically operates SVE systems that are equipped with catalytic oxidizers, thermal oxidizers, or activated carbon treatment. 

Groundwater Extraction & Treatment

Groundwater extraction and treatment is one of the oldest technologies used to remediate contamination.  This approach is useful in applications in situations where hydraulic control over the groundwater plume is needed, or where it is desirable to lower the water table to the effects of SVE.  Groundwater extraction can be performed at wells and trenches using a variety of pumping methods.

Dual-Phase Extraction of Soil Vapor and Groundwater

Blue Rock principals have conducted dual-phase feasibility tests and installed vacuum-enhanced dual-phase extraction and treatment systems.  Dual-phase systems are often highly successful at recovering contaminant mass because the lowered water from pumping results in greater soil vapor flow.  Dual-phase extraction is often suited for sites with more severe contamination.  Mobile dual-phase extraction rigs can also be used as a polisher for remnant “hot-spots” in order to hasten case closure.

Combined Soil Vapor Extraction & Air-Sparging

Combined soil vapor extraction and air-sparging (SVE/AS) is often a good approach at remediating a site where soil and groundwater are impacted with volatile contaminants.  The SVE portion of the system relies on the same principals discussed in the section above.  The AS portion of the system is used to inject air into the saturated zone.  This has a two-fold effect: (1) it physically strips volatile contaminants from the saturated zone which then travel upwards to be captured by the SVE system, and (2) it increases the level of oxygen in the saturated zone, thus stimulating aerobic biodegradation of contaminants. 

Bio-Sparging / Ozone Injection

Bio-sparging is very similar to air-sparging except it is done at a much lower flow rate so that no vapors are driven off the water table.  The goal of bio-sparging is to add just enough air to the saturated zone so that oxygen in the ground increases to levels needed to support ongoing aerobic biodegradation of contaminants.  This can also be achieved using other compounds or chemicals aimed at increasing oxygen levels.  Low levels of ozone can also be delivered to the saturated zone to chemically oxidize and breakdown contaminants.  This technology has two effects: (1) direct oxidation of contaminants, and (2) a release of oxygen follows the dissociation of ozone, which stimulates aerobic biodegradation of contaminants.  


Bio-venting is often most appropriate for sites contaminated with low-volatility hydrocarbons (i.e. diesel fuel).  A bio-vent system is designed similarly to an SVE system, but it operates at a lower flow rate with the goal of elevating oxygen levels in the vadose zone.  Bio-venting systems are typically operated in a manner that does not require air treatment, which results in minimizing equipment and maintenance costs.

Documented Natural Attenuation and Biodegradation

Blue Rock principals have successfully closed sites using rigorous approach in evaluating, confirming, and monitoring natural attenuation of contaminant plumes.  This approach includes documenting the rate at which contaminant levels are diminishing and examining the mechanisms behind the decline.  This approach is often a desirable in situations where contamination is not severe or the site has already undergone some active clean-up. 

Litigation Support

Blue Rock provides technical support during litigation involving disputes over environmental responsibility.  Blue Rock provides legal counsel a sound opinion regarding technical strength and weakness of data and realistic outcome of disputed site so that reasonable costs can be attributed to environmental damages. 

Government Contracting

Blue Rock principals have experience servicing small municipalities directly, or serving larger consulting firms on government projects.  Blue Rock collaborates with the client to identify key goals and requirements for the project, and finds ways to more efficiently achieve them.  On numerous occasions, Blue Rock principals have successfully streamlined work scopes to complete tasks in less time yet maintaining investigative integrity that resulted in net cost savings to the job.  Experience at government facilities includes Department of Defense locations throughout California. 

Cost Recovery Assistance

Blue Rock principals have been working with the California State UST Clean-up Fund (USTCF) since it came into existence in the early 1990s.  We have the experience and track record to ensure that our clients receive the maximum reimbursement of corrective action costs.  Over the past 15 years, Blue Rock principals have great personal track records in managing USTCF claims for their clients.