What Gregg Drilling & Testing Inc does

Gregg Drilling & Testing Inc (legally Gregg Drilling, LLC) is a California-based geotechnical and environmental site investigation contractor founded in 1985 and operating from Benicia (Northern California) and Signal Hill (Southern California). The company delivers project-based professional services across five overlapping service lines: Cone Penetration Testing (CPT) and supporting geotechnical testing (SPT, vane shear, pressuremeter, dilatometer); hollow stem auger, sonic, mud rotary, and direct-push drilling; environmental site investigation, monitoring well installation, and in-situ remediation injection; marine and nearshore drilling via the purpose-built R/V Quin Delta drill ship and modular barges; and specialized access work using amphibious platforms, heliportable rigs, and limited-access tracked units. Core proprietary technology includes 30-ton truck-mounted CPT systems designed and built in-house, the MiHPT combined MIP/HPT/CPT sensor stack for real-time contaminant and hydraulic characterization, and a mobile remediation injection platform capable of up to 100 GPM at 1500 psi.

Gregg serves engineering consulting firms (AECOM, Kleinfelder, WSP, Langan, Haley & Aldrich, Leighton, Shannon & Wilson) and government clients (California Department of Water Resources, Caltrans, NAVFAC, U.S. Army Corps of Engineers, Bureau of Reclamation, National Parks Service). Pricing is quote-based per engagement, with services delivered by Gregg's own field crews and equipment. The company is 100% owned by Sealaska, an Alaska Native Claims Settlement Act corporation, and operates under Sealaska's Woocheen business arm alongside sister companies Sealaska Marine Services, CS Marine Constructors, and Causeway Geotech, enabling coordinated offshore wind, marine cable route, and Delta-region project execution. The business holds federal 8(a) DBE, CUCP DBE, and CPUC MBE certifications, supporting set-aside procurement access in California.

Operations are licensed in California, Arizona, Nevada, New Mexico, and Oregon, with offshore experience extending to the Gulf of Mexico, U.S. East Coast, Puerto Rico, Mexico, Alaska, Canada, and Australia. Revenue mechanics derive from multi-month project engagements won through direct enterprise sales via project and operations managers, with a same-day or next-business-day quote response commitment and reinforcement through educational Field Day events and downloadable technical resource content.

Name

Gregg Drilling & Testing Inc

Legal name

Gregg Drilling, LLC

Website

https://greggdrilling.com

Company type

Private

Founded year

1985

Operating status

Operating

Headcount range

101–250 employees

Short description

Gregg Drilling & Testing Inc is a California-based geotechnical, environmental, and marine site investigation contractor serving engineering consulting firms and government clients across the Western US, with proprietary CPT equipment and a purpose-built marine drill ship.

Ownership category

akta.pro rank

Product category

Geotechnical and environmental drilling services

NAICS

Support Activities for Mining (21311), Support Activities for Oil and Gas Operations (213112), Drilling Oil and Gas Wells (213111), Geophysical Surveying and Mapping Services (541360)

SIC

Oil & Gas Field Services, Nec (1389), Services-Engineering Services (8711), Oil & Gas Field Exploration Services (1382), Drilling Oil & Gas Wells (1381)

akta.pro primary industry

Exploration & Production Drilling Services (RC, Core, Directional, Sonic, Auger) (IMAKAKAB)

akta.pro secondary industries

OFS Engineering, Construction & O&M (Field Development, Brownfield, Maintenance) (EUALABAM), Inspection, Integrity & Testing Services (NDT, Well Integrity, Corrosion, QA/QC) (EUALABAO), Seismic & Geoscience Services (Acquisition, Processing, Interpretation) (EUALABAK)

Keywords

• Geotechnical drilling services
• Environmental site investigation
• Cone penetration testing
• Marine drilling services
• Subsurface characterization

Headquarters

HQ city

Martinez

HQ country

United States

HQ region

North America

Offices2 records

Markets served

GTM type

B2B

Offering type

Services

Cost components

Personnel, Operations, Supply Chain, Infrastructure, Technology or R&D, Marketing or Sales

Revenue model

1. Geotechnical Site Investigation Services: Professional drilling and testing services for geotechnical site investigations including CPT, sonic drilling, rotary drilling, and auger drilling. Services are project-based with quotes provided per engagement.
2. Environmental Site Investigation and Remediation: Environmental drilling, sampling, monitoring well installation, and remediation injection services. Covers superfund sites, refineries, military bases, and dry-cleaner sites through to completion.
3. Marine and Near-shore Drilling Services: Overwater drilling and testing projects using R/V Quin Delta, barges, and support vessels. Includes vessel/barge positioning, marine surveying, dive support, and ROV support services.

Go-to-market motion1 record

Distribution channels1 record

Marketing channels3 records

Core offering

Gregg Drilling provides geotechnical and environmental site investigation services using company-owned, in-house designed equipment. Core offerings include Cone Penetration Testing (CPT), hollow stem auger drilling, sonic drilling, mud rotary drilling, direct push services, marine and nearshore drilling via the R/V Quin Delta drill ship, well installation and development, in-situ remediation injection, and advanced site characterization using Membrane Interface Probe (MiHPT) technology. Services are sold as project-based engagements to engineering consultancies, government agencies, and military clients for construction, environmental remediation, water resources, offshore wind, mining, and difficult-access applications.

Product overview

Gregg Drilling offers a comprehensive suite of site investigation services as a single unified service offering, not a software platform. The core portfolio centers on geotechnical and environmental drilling services including Cone Penetration Testing (CPT), Hollow Stem Auger Drilling, Sonic Drilling, and Mud Rotary Drilling. These are supported by specialized equipment divisions for marine operations (R/V Quin Delta drill ship, marine barges), limited access sites (Rhino, Wharthog, Ramset tracked units), amphibian platforms, heliportable rigs, and remediation injection platforms. The company provides end-to-end capabilities from initial site investigation through well installation to groundwater remediation, with advanced characterization technology like the Membrane Interface Probe (MiHPT) that combines MIP, HPT, and CPT for real-time subsurface analysis. Services operate across California and surrounding states with licensed contractor operations in Arizona, Nevada, New Mexico, Oregon, and California.

Differentiator

Problem solved

Functional benefit

Brands

• R/V Quin Delta: Purpose-built drill ship operated by Gregg Drilling for near-shore and marine drilling projects over the past 20 years, working up and down the West Coast from San Diego to Alaska.

Products and services

• Cone Penetration Testing (CPT) Geotechnical and environmental site investigations using truck-mounted, track-mounted, and portable ramset CPT equipment with up to 30-ton push capacity, delivering real-time subsurface data for engineering and environmental clients.
• Hollow Stem Auger Drilling Truck- and track-mounted auger drilling services for environmental and geotechnical investigations, supporting monitoring well installation up to 250ft depth.
• Sonic Drilling High-production sonic drilling using Fraste FS250 truck-mounted and Mid-Roto Sonic 50K track-mounted rigs for deep geotechnical, environmental, and exploration projects up to 1,000ft depth.
• Mud Rotary Drilling Geotechnical drilling services using standard mud rotary, reverse circulation, and flooded reverse methods with geotechnical sampling, piston sampling, and wireline coring capabilities.
• Direct Push and Limited Access Drilling Compact drilling solutions for constricted locations using tracked Rhino, Warthog, and portable Ramset units for geotechnical and environmental site investigations with minimal site disturbance.
• Membrane Interface Probe (MiHPT) Characterization Advanced subsurface characterization combining Membrane Interface Probe, Hydraulic Profiling Tool, and Cone Penetration Testing in a single push to provide real-time detection of chlorinated solvents and petroleum hydrocarbons along with groundwater regime and hydraulic conductivity data.
• Geotechnical Testing Services Comprehensive geotechnical testing including Standard Penetration Testing (SPT), vane shear testing, pressuremeter testing, and dilatometer testing for engineering projects.
• In-Situ Remediation Services Environmental remediation services including injection platforms for chemical delivery, multi-point manifolds, and reagent injection for groundwater cleanup at contaminated sites.
• Well Installation, Development and Abandonment Monitoring well installation, development, and abandonment services, including well rehabilitation and pump installation for environmental monitoring programs.
• R/V Quin Delta Drill Ship Service Nearshore and marine drilling delivered from a purpose-built drill ship with 5ft draft, hydrostatically controlled spuds, 4-point anchor system, central moon-pool, Mobile B-80 drill rig, and 20-ton hydrostatic cylinder for cone testing in shallow and deep water.
• Marine Barge Drilling Services Nearshore and marine drilling capabilities using modular barges, sectional barges, modular jack-up barges, and lift boats for various water depth conditions.
• Near-Shore Marine Services Marine site investigation services using purpose-built vessels for tidal mud flats, seabed surveys, and deep water cable route investigations.
• Advanced Site Characterization High-resolution site characterization combining CPT with MiHPT and UVOST technologies for detailed subsurface contaminant and geological profiling.
• Exploration and Mining Drilling Services Geological exploration and mining support services for resource assessment and extraction site investigations, including mineral exploration drilling.
• Well Development Services Quality well development and testing using Smeal pumps with video logging, water quality monitoring, and submersible pumps for environmental monitoring wells.

Quantifiable outcome

• Delta Conveyance project completed with $1.4M contract value
• +1 more outcomes

Named customers14 records

Segments6 records

Ideal customer profiles3 records

Technology focussed No

API detail

Has API

No

API docs

API detail

Core technology

AI maturity

App detail

Feature5 records

Partnerships

Five partnerships are on record, tiered core and major.

• Sealaska (Woocheen)coreStrategic or Co-development PartnerGregg Drilling is 100% owned by Sealaska as part of their Woocheen business arm focused on ocean health. Gregg works with other Woocheen companies including Sealaska Marine Services, CS Marine Constructors, and Causeway Geotech to address climate crisis and support offshore wind development. Revenue of Woocheen operating platforms has grown six-fold to roughly $1B since 2015.
• Sealaska Marine ServicescoreStrategic or Co-development PartnerPartnership with Sealaska Marine Services to support offshore wind development and green economy initiatives in the United States. Gregg has participated in East Coast site investigation projects supporting cable studies, HDD design, and offshore wind foundation design.
• CS Marine ConstructorsmajorStrategic or Co-development PartnerPartner company within Woocheen working together with Gregg to solve ocean health crisis. Cooperated on Delta Conveyance project providing barge support.
• Causeway GeotechmajorStrategic or Co-development PartnerSister company within Woocheen focused on geotechnical services. Colm Hurley, Southern California Regional Manager, previously served as Regional Manager for Causeway Geotech Ltd prior to joining Gregg.
• Pitcher ServicesmajorStrategic or Co-development PartnerCooperated on Delta Conveyance project providing on-land drilling and specialized testing (mud rotary drilling and pressuremeter testing) alongside Gregg's marine operations.

Scale indicators3 records

Recent moves6 records

Expansion highlights5 records

Direct peers

• Major Drilling Group International: Specialty drilling contractor serving mining, exploration, and geotechnical customers worldwide. Highly comparable service model — drilling rigs and crews on contract — though skewed more toward mineral exploration than environmental remediation.
• Boart Longyear: Global drilling services and equipment provider for mineral exploration, geotechnical, and energy markets. Directly comparable to Gregg in surface and underground drilling services, with broader geographic reach and a larger equipment fleet.
• Cascade Drilling: Environmental and geotechnical drilling services firm operating across the Western US. Closest direct peer to Gregg in CPT, sonic, auger, and direct-push drilling, with similar end markets in environmental remediation and construction site investigation.
• Layne (a Granite Construction company): Water well drilling, geotechnical, and mineral exploration contractor acquired by Granite Construction. Comparable service mix in water resource wells, monitoring wells, and geotechnical drilling, with substantially larger geographic footprint.

Emerging players

• Geoprobe Systems: Manufacturer of direct-push and environmental drilling equipment, including the Geoprobe rigs that compete with Gregg's tracked Rhino/Wharthog/Ramset fleet. Adjacent rather than direct — supplies equipment to many of Gregg's competitors and partners.

Broad incumbents

• Tetra Tech: Large consulting and engineering firm with deep environmental remediation and water resources practices. Overlaps with Gregg's customer base and could be a buyer or competitor for environmental drilling services.
• Fugro: Global geoscience and offshore site investigation specialist with a substantial marine geotechnical franchise. Highly relevant for Gregg's offshore wind and overwater drilling ambitions, though Fugro operates at vastly larger scale with proprietary geophysical vessels.
• Stantec: Global engineering, architecture, and environmental services firm. Similar customer relationships in water resources, infrastructure, and environmental remediation; competes for site investigation work but typically as the consultant-of-record rather than drilling contractor.

Others

• AECOM: Major engineering consulting customer of Gregg (Delta Conveyance and overwater drilling work). Not a direct competitor but a key buyer of Gregg's services whose procurement decisions shape Gregg's revenue trajectory.
• Haley & Aldrich: Geotechnical and environmental engineering consulting firm shown as a Gregg client. Serves the same end markets and often hires Gregg as a drilling subcontractor, making it a channel partner as much as a comparable peer.

Market position

Strengths5 records

Weaknesses5 records

Competitive moat5 records

Key risks5 records

Key highlights7 records

Customer concentration

Compliance4 records

Revenue estimate

Valuation estimate

Number of profiles

Profiles13 records

Funding overview

Funding rounds

Investors

Funding detail is available on the Subscription and Enterprise plan.Contact sales →

M&A

Investments

M&A and investment is available on the Subscription and Enterprise plan.Contact sales →

Frequently asked questions about Gregg Drilling & Testing Inc