Case Studies

Gregg Drilling & Testing Inc.

Creating a Corporate Culture of Innovation

Gregg Drilling & Testing Inc. (Gregg Drilling) keeps a relatively low profile on jobs, but the truth is that the construction industry would have a hard time building much of anything without companies like it. The team at Gregg Drilling provides the gamut of environmental, geotechnical and marine investigation and testing services. Gregg Drilling leverages the extensive expertise of its staff to design and refine its processes, leading to cost-effective technological innovations that provide accurate, reliable data with which to build a project. Above all, Gregg Drilling works to ensure the success of any project never comes at the expense of its employees’ safety.

John Gregg saw an opening in the California market for reliable, safety-oriented drilling and testing contractors, so he ventured out on his own in 1985 to establish Gregg Drilling. The company maintains headquarters in Signal Hill, Calif., and a second location in Martinez, Calif., to serve customers across the state and into Nevada, Arizona, Oregon, Washington and New Mexico. Gregg Drilling’s team numbers roughly 150 members that represent a mix of geotechnical and environmental professionals from a range of backgrounds, including industrial, academic and consulting.

In its earliest days, Gregg Drilling focused primarily on providing drilling and environmental services, especially on projects where contaminated soils were a concern. The company quickly established itself as a leader by investing in the latest technologies, equipment and most talented professionals to ensure a clear and accurate reading. Today Gregg Drilling’s geotechnical and environmental professionals provide drilling, soil and groundwater sampling, cone penetration testing (CPT), in-situ testing, as well as soil, rock and diamond coring.

Even after 25 years the company continues to go above and beyond to ensure its groundwater and soil-sampling equipment is effectively deployed and maintained between samples. The team ensures to not only avoid cross contamination, but also to minimize the investigative efforts’ environmental impact. The environmental team lends its expertise to such services as air vacuum excavation, video logging, well rehabilitation, pump installation and repairs, groundwater extraction, vapor extraction and contaminant screening using the cone penetration test (CPT).

Pushing the Limits

Gregg Drilling adopted CPT technology early on and the company remains one of the most prolific specialists employing the CPT in California. CPT helps identify the stratigraphy of soils in-situ and the direct push systems can be outfitted with additional modules to measure shear-wave velocity for seismic purposes. The units can also be outfitted with an Ultraviolet Optical Screening Tool (UVOST) module to detect the presence of hydrocarbons, which suggest the presence of oil and other petroleum-based contaminants. With the help of the CPT, Gregg Drilling produces reliable, repeatable results with minimal disturbance to the surrounding materials and plays a critical role in any successful soil remediation program.

The company also recruited the talents of Peter K. Robertson, Ph.D., one of the foremost authorities on CPT technologies, whose research has focused on in-situ soil testing, soil liquefaction, pile design, soil structure interaction and earthquake design of geotechnical structures. Dr. Robertson serves as a technical adviser of sorts and recently began a push to help educate Gregg Drilling’s clients through a free webinar series addressing CPT and its applications.

Gregg Drilling’s client-focused education has also involved the support and development of inexpensive yet powerful CPT-based interpretation software. The software was developed in partnership with Geologismiki in Greece, and is rapidly becoming the standard for CPT-based interpretation around the world.

The free webinars and inexpensive software underscores Gregg Drilling’s underlying commitment to not just employ state-of-the-art technologies, but to contribute to innovation. The company’s professionals have contributed their own experiences and expertise toward the design and development of specialized equipment, software, samplers and probes intended for site investigation purposes.

Investing in Innovation

Gregg Drilling custom-designs the company’s own CPT trucks and augments its fleet of new equipment by purchasing older models to be rehabilitated and refurbished to the company’s precise needs, according to Kelly Cabal, communications director at Gregg Drilling. The company also develops and operates some of its own CPT software programs.

More recently, the company spun off its geotechnical and environmental services for marine applications, which eventually became its own independent enterprise Gregg Marine. The marine offshoot operates equipment for sampling in both sub-sea conditions and closer to shore in ports and harbors.

Gregg Marine recently established a joint venture with Fugro Offshore Geotechnics under the name Seafloor Geotech LLC in 2012, which uses Gregg Marine’s patented robotic seafloor drill and wireline CPT system. John pioneered the technology’s development with the help of the team and California-based Schilling Robotics LLC.

The technology can record data for the uppermost 120 feet in water depths up to 13,000 feet. To facilitate exploration at such extreme depths, the team developed a suction system that works off of negative pressure to push the cone through the seabed soils. The design team also developed the module with a hydrostatically compensated and modified load cell design, ensuring the CPT probe would essentially tune out the external hydrostatic pressure, yielding more accurate soil readings in deep water.

Building Value

Over the years Gregg Drilling has lent its expertise to projects in a variety of sectors, including both public and private. The company works with clients around the world in oil and gas exploration and mining, as well as for municipal and federal water authorities and transportation agencies. Recent projects include some preliminary work for the high-speed rail project that will connect San Diego to San Francisco.

Gregg Drilling also provided geotechnical and environmental services for a project in the greater Los Angeles area that will eventually convert a contaminated site for public use. The project required extensive amounts of CPT recordings to a depth of 150 feet. Gregg Drilling deployed its arsenal of CPT equipment complete with a UVOST module to help identify the specific types of contaminants present in the soil so the client could develop a suitable remediation program.

Gregg Drilling managed to turn 2012 into a year of steady growth, and the team continues to position itself for further growth ahead with 14 of Gregg Drilling’s professionals celebrating 20 years or more at the company. Wherever the team chooses to focus its efforts, the company’s longtime employees will work to ensure Gregg Drilling & Testing Inc. retains the corporate culture of innovation that attracts top talent from many fields.

Published on: May 28, 2013

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