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Remediation of salt affected soils: Difference between revisions
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== Remediation goals == | == Remediation goals == | ||
Setting reasonable objectives | Setting reasonable objectives for the remediation effort is critical to developing a viable remediation plan. In some cases, the objectives may be established by legal, regulatory, or lease constraints. In other situations, the objectives may be based on more flexible criteria. It is advisable to, at a minimum, review the following factors prior to initiating any remediation effort: | ||
* Lease requirements | *Lease requirements | ||
* Regulatory constraints | *Regulatory constraints | ||
* Corporate policies | *Corporate policies | ||
* Environmental conditions | *Environmental conditions | ||
== Salt concentration == | == Salt concentration == |
Revision as of 15:38, 17 September 2015
Remediation of salt-affected sites can be performed for a number of reasons. Landowner claims; lease agreements; federal, state, and local regulations; reduction in long-term liabilities; company policies; and protection of useable land and water resources may be the driving forces behind the need to assess and restore a site affected by a saltwater release.[1] Water separated from oil and gas during production contains dissolved solids, including salts. If improperly handled, produced water with sufficient salt concentrations can damage plants and soils.
Remediation goals
Setting reasonable objectives for the remediation effort is critical to developing a viable remediation plan. In some cases, the objectives may be established by legal, regulatory, or lease constraints. In other situations, the objectives may be based on more flexible criteria. It is advisable to, at a minimum, review the following factors prior to initiating any remediation effort:
- Lease requirements
- Regulatory constraints
- Corporate policies
- Environmental conditions
Salt concentration
Salt concentrations of produced water from E&P operations vary from low salt concentrations to brackish water. Total dissolved solids (TDS) can range from less than 4,000 parts per million (ppm), to brines with salt concentrations greater than 100,000 ppm.[1]
Saltwater release
Total salt and total sodium concentration in a saltwater release can cause the soil to become saline and sodic. Produced water with high concentrations of total salts (salinity) and sodium (sodicity) can have a detrimental effect on terrestrial and freshwater environments. Excessive salts can create adverse chemical and physical conditions in soils and damage or kill vegetation.
Surface spills of produced water do occur as a result of:
- Equipment failure
- Pipeline corrosion
- Weather
- Human error
Disposal
Disposal of most inland produced waters is by injection into enhanced oil recovery or produced water disposal wells. Some inland facilities may use evaporation pits to dispose of produced water.
Injection
Evaporation pit
There are several types of pits traditionally associated with oil and gas production. Following are three types of salt-related pits:
- Production pit - Used for saltwater storage, oil and water separation, and solids settling (Moseley, 1983)
- Reserve pits - Used for solids separation during drilling and workover operations and for holding waste drilling muds and cuttings.
- Produced water storage (emergency) pits - Also known as Produced water storage are constructed to contain produced waters temporarily in the event of equipment malfunction.