Environmental Fracturing

Environmental fracturing has many benefits and is implemented in a variety of methods and configurations:

  • Permeability enhancement - increase the geologic pore space or dilate existing bedrock fractures
  • Passive treatment systems – permeable reactive barriers
  • Permeable reactive treatment zones – active zones with enhanced permeability for amendment injection such as ISCO or ISCR
  • Increase thermal well efficiency
  • Conventional remedial technology enhancement, i.e., pump & treat, DPE, SVE

It even has its place in the potable water industry for increasing the efficiency of public water supply wells.

A Citizen’s Guide to Fracturing for Site Cleanup

So how does environmental fracturing differentiate with fracking or hydrofracking in the energy industry?

In the environmental industry, fracturing has several benefits for expediting remediation or providing greater contact of remedial amendments. Two main methods are used – hydraulic fracturing and pneumatic fracturing – simply one uses liquid and one uses gas. The following table below lists a few other differentiators:

Considerations

Lithology

Fracture Tendency

Fracture Pattern

Amendment Delivery Capacity

Target Depth & Spacing


Hydraulic Fracturing

Silts, clays & bedrock (including swelling clays)

Creates new fractures

Larger single fracture

Higher

Typically between 10-300 feet bgs at 24-100 inch vertical spacing


Pneumatic Fracturing

Well-suited for “self-propping” lithologies

Dilate and propagate interstitial pathways

Micro-fracture network

Lower

Typically between 10-200 feet bgs (without proppant) at 24-40 inch vertical spacing

Hydraulic fracturing was first used in the oil industry in 1947 in Western Kansas to stimulate oil and gas wells. However, the issue became a public concern after the first Marcellus gas shale well was drilled and fracked in 2004, primarily due to its potential environmental impacts. Unfortunately due to this negative public perception, the word fracturing or fracking came under scrutiny even if the technology was benefitting the environment like enhancing potable water wells, a technology that has been used since the late 1960’s/early 1970’s.

Hydraulic Fracturing – Well Water vs. Oil and Gas, NGWA Position Paper, 2/10/10.


So how do you know if you need to fracture your site???
To Frac or Not to Frac – that is the question…
Your site may or may not need fracturing and this flow chart can help you decide.

Injection Flow Chart 12-2016