Requirements for horizontal directional drilling (HDD) environmental planning and construction monitoring vary greatly across North America, but regulatory obligations for planning and field monitoring of HDD construction are generally becoming more common. How will these changes affect your future projects? Working with an industry leader, like CCI is your first step. From there, here are the things you need to know.
Although they are generally used as a more environmentally friendly approach to installations in sensitive areas, trenchless construction projects are still inherently risky operations due to the potential for an inadvertent drilling mud release, the effects to land when disposing of drilling waste and potential environmental effects on the work site and crossing location. (Read also: Why is HDD better for the environment?)
Regulatory requirements are dynamic and responsive to upset conditions that have occurred in the past, especially if those upset conditions have led to impacts to a watercourse, impacts to a work site or impacts at a drilling mud disposal site.
Planning for Environmental Considerations
In addition to competent engineering and design, (specifically detailed hydro-fracture analysis,) environmental planning prior to a trenchless operation is one of the key steps in ensuring a successful and environmentally sound project. Planning includes regulatory interface to understand what acts, regulations and other regulatory instruments are applicable to the project, the acquisition of permits and authorizations to conduct the work, and engagement with stakeholders to understand and address their concerns as well.
Planning also includes the consideration of potential environmental effects that may be caused by and to the project while ensuring proper mitigation is presented in project plans to avoid or minimize those effects. The potential effects and mitigation are typically presented in an environmental protection plan, (supplemented by resource-specific environmental management plans,) as required by the project and specific construction details.
Planning is only the first piece to the implementation of a successful project. When moving into the construction phase of the project, diligence must be applied to ensure compliance with project requirements. Project requirements are defined as:
- Commitments made to the regulator or regulators during the permit application process.
- Commitments made to stakeholders such as landowners or Indigenous communities.
- Conditions attached to project approvals.
For this purpose, a trained and experienced environmental inspector is deployed to oversee the implementation of project environmental protection plan and/or environmental management plans, determine the effectiveness of the mitigation implemented and provide advice regarding adaptive management either to improve the mitigation or to ensure ongoing compliance with the project requirements.
An environmental inspector will also track any environmental liabilities during construction and ensure that they are addressed through clean-up and reclamation activities, or through post-construction monitoring programs. (Read also: Trenchless and the Environment: How No-Dig Construction Saves Eco-Systems.)
Regulatory Oversight and Compliance
The use of trenchless applications for the installation of pipelines, fibre optic cables and other underground assets has become commonplace due to its effectiveness in avoiding impacts to watercourses and other above ground structures. At the same time, rigorous environmental oversight during construction projects has become the norm as well, particularly in Canada and the Northeastern US.
This oversight is required to ensure compliance with project requirements, but also to ensure compliance with contractor plans and owner best management practices or standard operating procedures. It is common for a regulator to request construction plans for review prior to construction as well as a plan describing how those plans will be implemented.
Public concern regarding environmental protection and accountability has driven a change in the regulatory environment. Enabled by acts and regulations, regulators expect that environmental issues are considered prior to and during construction, and that environmental effects are either avoided or mitigated to reduce the impact caused by a construction project (For example, see the FERC “Guidance for Horizontal Directional Drill Monitoring, Inadvertent Return Response, and Contingency Plans” document issued in 2019).
There are multiple regulatory requirements and best management practices that are applicable to a trenchless construction project. Regulations or directives are created to ensure a project is built safely and in an environmentally responsible and sustainable manner.
These include engineering and design specifications and measures to protect the environment, administered by the state/province and the federal government. Not every jurisdiction is the same, so a firm understanding of the regulatory environment and its requirements and expectations need to be understood while planning a trenchless project. In some cases, regulatory requirements can be by far the most impactful component to the trenchless designs, more so than any other considerations or inputs (as examples, riparian zone setback limits, or safety-factor-against-hydro-fracture requirements for certain Army Corps of Engineers districts may dictate crossing lengths and/or depths more than double than would otherwise be implemented).
Environmental regulations will consider the construction process, which includes access and work area preparation, and the protection of environmental resources within or adjacent to the project site. Environmental regulations will also consider activities specific to the trenchless operation and address key environmental concerns, such as drilling waste management, water quality monitoring for watercourse or waterbody crossings, inadvertent release or frac monitoring and frac response.
Drilling Waste Management
Drilling waste management regulations include specific protocols regarding the condition of the soils at the disposal site for landspray and landspread, and subsurface soil conditions for sump storage and mix-bury-cover. To satisfy these conditions, sampling and analytical assessment of both the receiving soils and the drilling mud are obtained to ensure that the receiving soils will not be impacted by the disposal of the drilling waste. The details of a drilling waste management program are presented in a Drilling Waste Management Plan, providing strategies and direction for the safe and environmentally responsible disposal of drilling waste. (Read also: 10 Drilling Waste Disposal Options.)
Water Quality Monitoring
In many jurisdictions throughout North America, water quality monitoring is typically required while performing trenchless construction under a watercourse or a waterbody. A Water Quality Monitoring Plan will be developed to ensure adequate sample locations and sample frequency, allowing an environmental inspector to determine if the trenchless operation is affecting the waterbody.
Turbidity is measured to determine if there is an increase from the background levels. If there is an increase, further investigation and assessment is required to identify the cause of the increase and determine if mitigation measures are required to avoid effects to the aquatic environment. This requirement has been standard throughout Canada for years and is becoming more and more present in the US.
Regulators will also require a plan to ensure that monitoring for inadvertent mud releases forms part of the construction program, and that risk for a release of drilling fluid to the surface is considered and mitigated. Frac walks are conducted on a regular basis along and adjacent to the drill path to determine if there has been a release of drilling mud to the surface during the trenchless operation, especially if drilling mud returns to the drilling rig diminish, or if anomalies are identified by the downhole annular pressure monitoring tooling. The specifics regarding which areas are to be monitored and frac walk frequency are included in a Frac Monitoring Plan.
A Frac Response Plan will be enacted should an inadvertent drilling mud release occur. The Frac Response Plan will consider both aquatic and terrestrial releases and will describe the steps to be taken to respond to a release and minimize the effects to the environment. Inadvertent releases are to be contained as soon as it is safe to do so and cleaned up as soon as possible to avoid potential sedimentation to the surrounding environment. Additional measures may have to be applied to control and prevent further releases at a frac location.
Good environmental stewardship for a trenchless project starts with regulatory and environmental planning and is executed through competent oversight by an environmental inspector. Site-specific environmental and resource concerns will be identified during an assessment process and addressed via the regulatory process through the development of plans to avoid, mitigate and/or minimize environmental effects. The environmental planner will work directly with the project team and the regulator to acquire regulatory approvals through the provision of required information to the regulatory body.
Once all plans are developed to address project requirements, an environmental inspector becomes a key construction team member to ensure the project remains in compliance. An environmental inspector is tasked with overseeing the implementation of the project plans, provide advice in adaptive management situations, and work directly with the construction management team and contractors to ensure the environment is protected and the project is compliant. The key environmental concerns will be monitored and acted upon on a daily basis.
The environmental inspector will also oversee the clean-up and reclamation of the construction site. This will ensure that natural contours and drainage patterns are restored, and the project footprint is returned to a condition that will allow for successful reclamation.
While in the field, an environmental inspector is responsible for the tracking of environmental information and reporting required by the project. These reports and the data collected during construction will be referenced when developing the final post-reports, as required by the owning company or the regulator.
Through environmental planning prior to construction and environmental inspection during construction, a project owner will mitigate risk to non-compliance situations and environmental effects, setting up the project for regulatory and environmental success.