Saltwater Damage & Sodic Soil Reclamation
Sodic Soil Reclamation using L-GYP
Salt contamination of soils is a serious environmental issue facing the oil and gas industry today. Sodic Soil or saltwater damage from produced water spills and leaks can completely devastate surrounding vegetation. Until recently, sodic soil reclamation has been a time consuming, ineffective and expensive process. Newly developed technology offers a fast, easy and cost-effective way to remediate salt damaged soils.
Sodium affected soils have poor physical properties and commonly have crusted surfaces which prevent water percolation, causing runoff and erosion. Remediation of sodium damaged soils in a timely manner necessitates replacing the exchangeable sodium with a stronger and more favorable cationic source. Research and experience have shown that the sodium (Na+) levels in the soil structure can be reduced through electrolyte manipulation, replacing the damaging sodium with more desirable minerals.
In the past gypsum, lime or calcium nitrate have been used to attempt to accomplish this, however with poor results. The low solubility of gypsum, lime or the negative environmental impact of nitrates makes these poor and costly choices.
After 20 years in the soil remediation business, and trying several different calcium products, it became apparent we needed to find a better solution. We spent over a year researching and working with agronomists to develop a product that supplies the needed calcium without the detrimental effects of chlorides or nitrates.
Sodic Soil Reclamation Midway
Our new sodic soil reclamation product is called L-GYP. It is a true liquid gypsum, unlike other products currently available, L-GYP contains no chlorides or nitrates. The calcium in this product is 100% soluble. It contains only Calcium and Sulfur, both of which are essential for proper soil remediation of brine impacted soils.
Sodium chloride is the primary salt associated with oil field produced waters. Soils exposed to high salt levels become sodium saturated and/or sodic (ESP > 15%). Calcium amendments counteract sodicity and high salinity. Due to its low solubility, Gypsum is only an effective amendment when time is NOT a factor and mechanical means are available for distribution and mixing into the soil profile. It typically takes a minimum of 5 years for the Calcium in agricultural gypsum to dissolve.
This is why L-GYP is the preferred product. Since it is in a liquid form, the Calcium is immediately available, the ion exchange happens quickly. L-GYP also has an organosilicone surfactant added, commonly called a superwetter, which makes the product penetrate the soil profile quickly and evenly. Another benefit is reduced volume of product needed, since 50 gallons of L-GYP is equivalent to 1 ton of gypsum.
Salt water damaged sites can be restored.
Sodic Soil Reclamation Finishing
The most common procedure for correcting sodium affected soils is to amend the soil with materials that replace the exchangeable sodium on the soil colloids. Remediating sodium damaged soils in a timely manner requires lowering the exchangeable sodium percentage (ESP) with a stronger more favorable cationic sources. The result is the displacement of the sodium ions in the soil, which are then free to be flushed out of the growth zone.
In sodium affected areas, nutrients are often stripped from the soil depriving plants of the proper nutrition for growth. Once the sodium has been treated and removed from the soil, proper plant nutrients are required for plant recovery and re-growth. L-GYP removes the sodium plus increases the nutrient uptake of the plant improving plant structure and new growth.
Soil samples should be taken and analyzed. We need to know the Electrical Conductivity (EC), Sodium Adsorption Ratio (SAR), Cationic Exchange Capacity (CEC) and the Exchangeable Sodium Percentage (ESP).
The target values are EC<4.0 mS/cm, SAR < 12, and ESP < 15%
CEC is a measure of the soils ability to exchange cations, sandy soils have a low CEC, clayey soils have a high CEC.
The formula for calculating L-GYP requirements is as follows:
(Actual % ESP - 12% ) x CEC =(Charge Requirement)(1.7tons/acre-ft)
100
Example:
Site is 1/3 acre, Damage is 2 feet deep, ESP is 46, CEC is 20
(46% - 12% ) x 20 =
100
This equates to 6.8 which we then multiply by 1.7 tons/acre-foot, leaving us with 11.56 tons gypsum/acre-ft.
1/3 acre x 2 ft deep = .666 acre-ft x 11.56 tons = 7.69 tons gypsum
50 gal L-GYP x 7.69 tons gypsum requirement = 384.5 gal L-GYP
This site would require 384.5 gallon L-GYP to remediate 1/3 acre2 feet deep. After the site has been properly prepared the L-GYP should be mixed 10 to 1 with fresh water and applied to site and watered in with 3 inches of water minimum, 6 inches preferred.
Procedure to remediate this site is as follows;
- Rip site to a depth of 2 ft
- Mix in 7 tons of hay (10 tons/acre ft minimum)
- Mix 385 gal L-GYP in 3850 gallons fresh water
- Apply mixture to site
- Water in with 54,000 gallons fresh water minimum
- 110,000 gallons water is preferred
- Sample site in 60 days and seed with desired crop
1 inch of water is 27,000 gal per acre. So 3 inches of water is
27,000 x 3 = 81,000 gal x .666 = 53,946 gal water.
It takes 3 inches of water to drive L-GYP 1 foot deep since damage is 2 foot deep, we recommend 6 inches of water or 110,000 gal. It is alright if water pools on site as long as it doesn't run off. Some sites can be bermed to prevent runoff.
If downward leaching of salt is a concern, many times we have added french drains to a sump so leachate can be recovered and disposed. If you have any questions please call, we have been selling L-GYP for over 2 years with great success.
Get our Material Safety Data Sheet for L-GYP