Land reclamation encompasses
a variety of disturbance sources, some natural, such as beach erosion leading
to beach restoration, others anthropogenic, such as mining and oil & gas.
Some reclamation is induced as a preventative measure to other problems, such
as wetlands reclamation, where wetlands are drained to make land buildable, and
stream reclamation to prevent flooding. That is perhaps confusing since this
type of land reclamation can destroy wetlands that have environmental benefits.
Landfilling with soil and sand is practiced to expand urban areas.
Land restoration is the final
goal of all land reclamation. Land restoration aims to bring land back to its
natural state, and stream and wetland restoration is done to bring those water
bodies back into a natural state. Any construction site or activity, such as
road construction, where land is disturbed, requires some degree of
reclamation. Those sites will often have things like erosion blankets, straw
mulching, grass seeding, water catchment basins, topsoil return, and other
features to improve drainage and reduce erosion and sedimentation. I will focus
more here on oil & gas site reclamation than mine lands reclamation, which
can be more extensive since it often encompasses much more land disturbance,
and is a vaster subject.
According to Grass Plus
Landscaping, land reclamation and restoration:
“…involves rehabilitating areas affected by industrial
activities, natural disasters, or other human interventions. Land reclamation
aims to return the land to a productive and sustainable state while mitigating
the negative impacts of its previous condition.”
Examples of land reclamation and restoration include
converting abandoned mine lands into recreational areas, converting
“brownfields” into “greenfields” for urban development, and creating wetlands
for biodiversity. They give six techniques used in land reclamation and
restoration:
1) Soil
Replenishment and Enhancement – This simply
involves replacing stripped-off soil with new soil of sufficient properties and
fertility. The addition of specific plants and microorganisms can aid the
chemical breakdown of pollutants.
2) Erosion
Control Measures – this refers to stabilizing the soil via the
prevention of erosion and sedimentation.
3) Grading
and Reshaping – This refers to grading and contouring the land to a
natural shape that leads to effective and efficient drainage of the site
without additional erosion and sedimentation.
4) Water
Management and Treatment – This involves redirecting
water via channels, drainage ditches, and underground pipe drainage. Water may
also be treated for contaminants via physical, biological, and chemical
processes.
5) Reintroduction
of Native Plants and Wildlife – This is important
for restoration. The ability of reclaimed land to support native species is
also a measure of success and a primary goal.
6) Monitoring
and Adaptive Management – This involves site monitoring
and implementing adaptive management strategies. It may involve making
adjustments to improve the site as more data is gathered and analyzed. It may
continue for several years until the site is deemed fully restored.
Mine Lands Reclamation
“Abandoned mine lands (AMLs) are those lands, waters and
surrounding watersheds where extraction, beneficiation or processing of ores
and minerals has occurred. AMLs can pose serious threats to human health and
the environment. The EPA conducts and supervises investigation and cleanup
actions at a variety of mine sites. The Agency has a range of resources related
to the environmental risks and challenges present in investigating and cleaning
up AMLs. The EPA also pursues opportunities to explore innovative reuse
opportunities at mine sites.”
Ongoing mine land reclamation
projects include acid mine drainage treatment and abatement programs, which can
take many years to complete, and re-establishment of chemical treatment systems
since the rocks and materials, such as limestone and steel slag, can get degraded over time. Other issues of importance in mine lands reclamation include mine
subsidence, mine water releases, and impoundment overflows. Many of these
processes need to be monitored long-term.
The U.S. government collects
fees per ton of coal produced to pay for reclamation activities, as shown
below.
Oil and Gas Site Reclamation
Oil and gas site reclamation
in the past was often guided by the Bureau of Land Management’s (BLM) book:
Surface Operating Standards and Guidelines for Oil and Gas Exploration and
Development, also known as the Gold Book. The USGS and the BLM issued new
guidelines for oil & gas site reclamation in January 2024. The reclamation
section in the Gold Book stresses the need for planning as well as interim
reclamation, which refers to ongoing reclamation during the development of the
site.
“Planning for reclamation prior to construction is
critical to achieving successful reclamation in the future. Reclamation becomes
significantly more difficult, more expensive, and less effective if sufficient
topsoil is not salvaged, interim reclamation is not completed, and if proper
care is not taken to construct pads and roads in locations that minimize
reclamation needs.”
Erosion control is an
important feature of land reclamation. It is deemed sufficient when:
“…adequate groundcover is reestablished, water
naturally infiltrates into the soil, and gullying, headcutting, slumping, and
deep or excessive rilling is not observed.”
The site should also be free of invasive species, noxious
weeds, oilfield debris, contaminated soil, water, or equipment. Reclamation
plans should include plans for interim and final reclamation. If the well is to
be plugged and abandoned, then a new reclamation plan must be submitted to
reclaim the land used for the wellsite. Filling in and reclaiming pits is an
important part of oilfield reclamation. The pits must be drained of liquids,
then the liner removed, and all fluids contaminated with oil or brine must be
removed. Sometimes pits may be solidified in place with the solids and the
liner remaining in place to be buried. The pit covering should be mounded to
account for the extra settling over the area. The remaining liner should not
interfere with revegetation.
“All oil and gas drilling-related CERCLA hazardous
substances removed from a location and not reused at another drilling location
must be disposed of in accordance with applicable Federal and State regulations.”
Regarding site prep and
revegetation, the section in the book is succinct, informative, and repeated
here:
“Site Preparation and Revegetation”
“Disturbed areas should be
revegetated after the site has been satisfactorily prepared. Site preparation
will include respreading topsoil to an adequate depth, and may also include
ripping, tilling, disking on contour, and dozer track-imprinting. The operator
will usually be advised of the revegetation methods, objectives, and seasons to
plant, unless this information is included in the Application for Permit to
Drill (APD) reclamation plan. Native perennial species or other plant materials
specified by the surface management agency or private surface owner will be
used. Seeding should be accomplished by drilling on the contour whenever
practical or by other approved methods such as dozer track walking followed by
broadcast seeding. Seeding or planting may need to be repeated until
revegetation is successful, as determined by the surface management agency.”
Mulching, fertilizing, irrigating, fencing, or other
practices may be involved in the revegetation effort. Climatic conditions such
as drought, weather, season, and land use, such as for cattle grazing, are also
factors in revegetation. The previous plant community at the site should be
documented and recreated, if possible, to optimize the return of the original
ecosystem. Effective topsoil return, remediation of contaminated or compacted
soil, are other factors.
Guidelines for pipelines
include co-locating them with roads as much as possible. This section is also
succinct and informative, so I will repeat a section of it as well:
“Pipeline trenches are to
be compacted during backfilling and must be maintained to correct backfill
settling and prevent erosion. Reclamation involves placing fill in the trench,
compacting the fill, regrading cut-and-fill slopes to restore the original contour,
replacing topsoil, installing temporary waterbars only where necessary to
control erosion, and revegetating in accordance with a reclamation plan.
Waterbars and other erosion control devices must be maintained and repaired as
necessary.”
“Following successful
revegetation, surviving waterbars must be flattened to blend with the slope and
then revegetated. If berms of topsoil were originally placed over the trench to
accommodate settling, the surviving berms should also be flattened to blend
with the surrounding landform and revegetated.”
“Final abandonment of pipelines and
flowlines will involve flushing and properly disposing of any fluids in the
lines. All surface lines and any lines that are buried close to the surface
that may become exposed due to water or wind erosion, soil movement, or
anticipated subsequent use, must be removed. Deeply buried lines
may remain in place unless otherwise directed by the authorized officer.”
Waterbars are drainage ditches that divert surface water
away from the site.
Interim reclamation at the
well site involves reclaiming any part of the site not needed for continuing
operations. Those portions are recontoured to blend in with natural contours.
Topsoil should be re-spread over those areas and then seeded with suitable
plants.
“To reduce final reclamation costs; maintain healthy,
biologically active topsoil; and to minimize habitat, visual, and forage loss
during the life of the well, all salvaged topsoil should be spread over the
area of interim reclamation, rather than stockpiled. Where the topography is
flat and it is, therefore, unnecessary to recontour the well location at the
time of final reclamation, the operator may set aside sufficient topsoil for
final reclamation of the small, unreclaimed area around the wellhead. Any topsoil
pile set aside should be revegetated to prevent it from eroding and to help
maintain its biological viability. On sloped ground, during final reclamation,
the topsoil and interim vegetation must be restripped from portions of the site
that are not at the original contour, the well pad recontoured, and the topsoil
respread over the entire disturbed site to ensure successful revegetation.”
Final reclamation should not
rely on revegetation alone, but also restoration as much as possible to the
original landform, with topsoil redistributed evenly. Topsoil restriping should
precede recontouring. Backfills are best performed in dry conditions, if
possible.
“Water breaks and terracing should only be installed
when absolutely necessary to prevent erosion of fill material and should be
removed when the site is successfully revegetated and stabilized.”
Portions of the roads not
needed for continuing operations should be reclaimed. Cut slopes, fill slopes,
and borrow ditches should be covered with topsoil and revegetated. At final
abandonment, the roads must be reclaimed unless an agreement is made with the
surface owner and regulatory agency. Removal of undesirable vegetation and
recontouring to match natural contours is also done.
Restoration includes,
foremost, a return to the original ecosystem, and this process takes time and
should be monitored over time. Ecosystem restoration includes the restoration
of the natural vegetation, hydrology, and wildlife habitats.
The new USGS/BLM oil & gas site
reclamation guidance adds more BMPs, including for post-reclamation site
monitoring.
“Resource inventory, monitoring, and protection of oil
and gas sites are mandated by federal statutes and regulations, yet this is the
first publication defining standards and guidelines for how to successfully
monitor soil and vegetation outcomes of disturbed oil and gas sites and
evaluate those monitoring data against standards available at a national level.
The report emphasizes the importance of best management practices, clear
standards, effective monitoring and minimizing surface disturbance for successful
land reclamation.”
The BLM separates oil &
gas site reclamation into four phases: pre-construction, construction and
operation, post-construction, and long-term. State agencies or the BLM approve
reclamation plans. BLM and/or state agency inspections occur most often in the
post-construction phase. According to the USGS:
“…reclamation benchmarks include indicators of erosion and
site stability, species composition and community structure.”
“Successful reclamation is achieved when the standards
defining soil and vegetation recovery are met, and a self-sustaining, vigorous,
diverse, native, or approved plant community that minimizes visual land
disturbance, provides forage, stabilizes soils and prevents noxious weeds from
taking hold is in place.”
As can be seen from the map
below, the BLM mainly regulates areas in the Plains and the Western U.S. Below
that are the BLM’s work flows for interim and final reclamation and
restoration. The third figure below shows soil suitability to be considered for
use as topsoil.
The temporary use of wooden
mats can minimize soil and vegetation disturbance.
For pipelines, the use of
bucket augers and rock or wheel saws can minimize soil and vegetation impact.
There are best management
practices (BMPs) for vegetation removal, weed prevention and management, soil
ripping and tilling, topsoil storage and handling, erosion control, seed
quality and application, soil amendments, interim weed control, and long-term
site monitoring.
Erosion and Sedimentation Control
The goal of erosion and
sedimentation control is to increase the drainage of surface water off the
disturbed land without the transport of sediment off the site. Disturbed soils
where vegetation and topsoil are removed become very vulnerable to erosion by
wind, surface water, and rain. BMPs for erosion control include reducing slope
angles during earthwork, consideration of site-specific features, protection of
stored topsoil and fill dirt, the use of erosion control matting, polypropylene
erosion control blankets, double net matting or blankets for steeper slopes,
interim revegetation where applicable, raindrop impact protection,
hydro-mulching to stabilize steep slopes, final slope of 4-6% where applicable,
prevention of water ponding, the use of water barriers, embankment reshaping,
and checking the site after heavy rainfall events.
“To prevent erosion during construction, diversion
terraces and ditches, mulch, riprap, fiber matting, temporary sediment traps,
broad-based drainage dips, water bars, lateral furrows, biodegradable wattles,
weed-free straw bales, or silt fences are employed as necessary to reduce
offsite transport of sediments. These structures are installed during
construction and left in place and maintained until the site undergoes interim
reclamation.”
Grass Plus Landscaping
divides erosion control into five strategies:
1) Vegetation
Establishment – This is usually the preferred way to control
erosion if it is possible.
2) Mulching –
Straw, wood chips, and geotextiles are used for mulch, which protects the site
against raindrop impacts, reduces evaporation, and retains moisture for
vegetation.
3) Terracing
and Contouring – These are used on steeper slopes with the final
goal of matching the natural topography.
4) Erosion
Control Blankets and Matting – These are used to
prevent severe erosion, typically on steeper slopes.
5) Drainage
Management – This typically includes constructing ditches, channels,
and retention ponds.
Regulations and Regulatory Issues
For coal and minerals mine
reclamation, the first big rule in the U.S. was the Surface Mining Control and
Reclamation Act (SMCRA) of 1977. Any hazardous substances spilled or remaining
after reclamation at oil & gas sites are subject to the Comprehensive
Environmental Response, Compensation, and Liability Act of 1980 (CERCLA). Other
federal laws and numerous state laws often apply as well. Other agencies also
have land reclamation guidance, including the USDA, USGS, BLM, and EPA.
Land Reclamation and Restoration Challenges
Grass Plus Landscaping gives
five challenges of land reclamation and restoration:
1) Site
Complexity and Diversity – Each site is unique with
different topography, soils, potential contamination sources, and more.
2) Financial
and Time Constraints – Land reclamation and restoration are often
expensive and time-consuming but must be integrated with project timelines.
3) Stakeholder
Engagement – Addressing the concerns of surface owners and other
local stakeholders is important.
4) Legal
and Regulatory Compliance – Different permits and
standards may apply in different places.
5) Long-Term
Sustainability – This is the final goal, but ongoing management may
be necessary to achieve it.
References:
Land
Reclamation and Restoration: Techniques and Challenges. Grass Plus Landscaping.
November 25, 2023. Land Reclamation and Restoration:
Techniques and Challenges
The
Comprehensive Guide to Land Reclamation: Expanding Horizons Responsibly,
G3SoilWorks. G3 Blog. June 30, 2024. Comprehensive Guide to Land
Reclamation
Oil
and Gas Site Reclamation. Bureau of Land Management. Oil and Gas Site Reclamation | Bureau
of Land Management
Oil
and Gas Reclamation – About. USGS. Oil and Gas Reclamation - About |
U.S. Geological Survey
Land
Reclamation. Trihydro. Land Reclamation | Erosion Control
& Revegetation | Trihydro
USDA Natural
Resources Conservation Service. CONSERVATION PRACTICE STANDARD. LAND
RECLAMATION, LANDSLIDE TREATMENT. CODE 453 (ac). September 2022. Conservation Practice Standard Land
Reclamation, Landslide Treatment (Code 453)
New
guidelines for successful oil & gas reclamation. USGS. January 26, 2024. New guidelines for successful oil and
gas reclamation | U.S. Geological Survey
How
and why U.S. energy developers can achieve a robust ecological impact strategy.
Ellie Murphy. American Society of Reclamation Sciences. Reclamation Matters.
Spring 2024. Reclamation-Matters_Spring-2024.pdf
Surface
Operating Standards and Guidelines for Oil and Gas Exploration and Development:
The Gold Book. Bureau of Land Management. Fourth Edition - Revised 2007. GEN15-BLMGoldBook.pdf
Reclaiming
Abandoned Mine Lands: Title IV of the Surface Mining Control and Reclamation
Act. U.S. Department of the Interior. Office of Surface Mining Reclamation and
Enforcement. Reclaiming Abandoned Mine Lands |
Office of Surface Mining Reclamation and Enforcement
Oil
and Gas Reclamation—Operations, Monitoring Methods, and Standards: Chapter 1 of
Section A, Reclamation Activities. Book
18, Land and Resource Management. U.S. Geological Survey and Bureau of Land
Management. December 28, 2023. TM 18–A1: Oil and Gas
Reclamation—Operations, Monitoring
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