At Silkstone Environmental, we deliver high-quality Phase 2 Site Investigations. These investigations provide the detailed ground and contamination data required to validate or refine the conclusions of your Phase 1 Preliminary Geo-Environmental Risk Assessment (desk study) and to support design, remediation, planning, or development decisions.
Whether you’re a developer, landowner, consultant, or regulator, our Phase 2 services give you confidence in subsurface conditions, risk quantification, and remedial strategy.
What Is a Phase 2 Site Investigation?
A Phase 2 Site Investigation involves direct, on-site sampling of soils, groundwater, monitoring of ground gases, and recording of geological strata to assess the nature, extent, and severity of contamination or ground hazards. It follows a Phase 1 report when further data is needed to support planning, design, remediation, or due diligence.
Phase 2 investigations are critical for:
- Validating and refining conceptual site models (CSMs)
- Determining whether remediation is required (and how)
- Informing the design of foundations or earthworks
- Satisfying planning conditions
- Quantifying risk to human health, surface and groundwater, ecology, and property
Our work is aligned with UK best practice, including the Environment Agency’s LCRM (Land Contamination Risk Management) framework, CIRIA guidance and British Standards.
What Does a Phase 2 Investigation Include?
We tailor each investigation to your site’s context, but typical tasks include:
Intrusive drilling and trial pitting
To access subsurface soils, structure, fill, and geology
Soil sampling and laboratory testing
Chemically screen, quantify pollutants (e.g, heavy metals, hydrocarbons), and test geotechnical properties
Groundwater sampling
Determine water quality (e.g, dissolved contaminants) and groundwater levels
Ground gas monitoring & risk assessment
Assess methane, carbon dioxide, or vapour intrusion risk and in the case of mine gas, risk from carbon monoxide, hydrogen sulphide and air depleted of oxygen
In situ testing & logging
SPT, permeability, vane shear, CPT – characterise soil/rock strength and hydraulic properties
Groundwater monitoring boreholes
Long-term water level and contaminant monitoring
Geotechnical logging and geological interpretations
Understand strata, structure, anomalies, and hazards (e.g, Made Ground, voids, contamination plumes)
Data integration & refined conceptual site model
Incorporate all field and lab data into a refined CSM
Risk evaluation & remedial recommendations
Decide whether unacceptable risks exist, and propose remediation or mitigation strategies
Reporting to meet regulatory/planning requirements
Provide a clear,. professional report acceptable to planning authorities, environmental regulators, or lenders.
Why Choose Silkstone for Phase 2 Investigations?
We bring together technical expertise, practical delivery, and client-focused service. When working with us, you benefit from:
- Qualified and experienced engineers using UK standards and guidance
- Rigorous health & safety and environmental management
- Clear and accessible reporting
- Pragmatic, cost-effective investigation designs tailored to your risk profile
- Timely delivery and responsive service to keep your project on schedule
- Confidence in regulatory acceptability, supporting planning, permitting, or contaminated land regimes
When Is a Phase 2 Investigation Needed?
You’ll likely require a Phase 2 investigation in scenarios such as:
- The Phase 1 Desk Study flags potentially unacceptable risks
- Planning conditions demand intrusive investigations.
- You are acquiring or disposing of land and require due diligence.
- You want to finalise foundation, earthworks, or piling designs.
- There is known contamination or a historical industry on or near the site.
- Ground gas, hydrogeology, or filled ground are suspected.
- You are funding or insuring the site, and require robust, defensible data.
Our Approach & Project Flow
Every great project starts with a clear plan. Here’s our approach to making yours a success.
1. Scoping & Site Familiarisation
We review the Phase 1 report, site constraints, historical data, and client objectives to propose a bespoke investigation scope.
2. Permitting & Access Arrangements
Liaise with landowners, statutory bodies, highways, utilities, and third parties to secure access, safety arrangements, and consents.
3. Field Investigation
Mobilise drilling rigs, samplers, gas monitoring, geotechnical testing, and other specialist equipment. Collect samples and in situ data.
4. Laboratory Analysis & QA/QC
Samples are sent to UKAS-accredited laboratories for chemical, physical, and geotechnical testing. Quality assurance is maintained throughout.
5. Data Review & Interpretation
Integrate field logs, chemical results, groundwater data, and other metrics into a refined conceptual site model. Assess pollutant distribution and risks.
6. Reporting & Recommendations
Provide a comprehensive report, including plans, cross-sections, tables, risk assessment, and remediation / mitigation options. Present a clear way forward for design or planning purposes.