Brine Disposal Alternatives

Options for Disposing of DesalinationConcentrate and Water Treatment Residuals

Anthony E. Bennett, R.S.Technical DirectorAECOM Water

Anthony E. Bennett, R.S.Technical Director

AECOM Water

Introduction

BackgroundOffshore DischargeInland Surface Water DischargeIrrigationSurface impoundmentUnderground Injection

Background

Desalination initiativeSeawater desalinationSeawater desalinationBrackish groundwaterBrackish groundwater

Recent Drinking Water StandardsArsenicArsenicRadionuclidesRadionuclidesStage 2 Surface Water TreatmentStage 2 Surface Water Treatment

Discharge to freshwater surface water(TPDES individual permit required)

Freshwater surface water usecan be adversely affected byincreases in salinityConcentrate TDS typically

much greater than waterquality standardsSalinity, Metals, toxic

substances, and naturallyoccurring radioactive materialsare concentrated bymembrane technologydesalination and can be apossible concern

Discharges to Publicly Owned Treatment Works (POTWs)(no TCEQ permit required)

Ability of the POTW to accept the wastewatervolume of the concentratevolume of the concentratesalinity of the concentratesalinity of the concentrate

Irrigation(TLAP individual permit required)

Any buildup of salt constituents can become toxic to thecrop and/or the soil biosphereWithout the crop and soil mechanisms, there is anincreased probability of impacting surface waters and/orimpacting groundwater

Surface Impoundment Evaporation(TLAP individual permit required)

No discharge to water in thestate is authorized by thisdisposal methodDisposal is entirely dependenton the evaporation rates in thelocation of the facilityImpoundments must be sizedproperly and lined toappropriately deal with overflowand prevent discharges(percolation) to groundwater

Solid Waste Disposal

Treatment residuals which can de driedTreatment residuals which can pass the TCLP can bedisposed of in municipal waste sitesTreatment residuals which cannot pass TCLP must behandled as hazardous waste

Discharge to marine surface waters(TPDES individual permit required)

No numerical water quality standards for TDS or ChlorideDischarges can adversely affect aquatic ecosystems ofestuaries and tidal riversMetals, toxic substances, and naturally occurringradioactive materials can be a concernDischarges further than 3 leagues offshore are underEPA jurisdiction

Underground Injection(UIC permit required)

Under Federal and Texas Statutes and regulations, apermit is required if disposal will occur below the base ofunderground source of drinking waterDisposal of a waste stream into a Useable Source ofDrinking Water (USDW) that is not hazardous and cannotdegrade an underground drinking water source isauthorized by rule (Class V)

Class I Injection Well

Injection of non Oil and Gas Waste below a UseableSource of Drinking Water (USDW)HB 2567 exempts Class I Desal disposal wells fromcontested case hearing

Class II Injection Well

Salt water co-produced with oil and gasFluids for enhanced recovery of oil and gasStorage of hydrocarbons that are liquid atstandard temperature and pressureWithout further federal rulemaking,desalination concentrate would have to beinjected into oil and gas producing zones forlegitimate enhanced recovery

UIC Revisions Under HB 2654

HB 2654 passed by 80th Texas LegislatureProvides for

State rules to allow desalination and other drinking waterState rules to allow desalination and other drinking watertreatment residuals into enhanced recovery wells permitted bytreatment residuals into enhanced recovery wells permitted byTXRRC without a Class I permit from TCEQTXRRC without a Class I permit from TCEQClass I permits by TCEQ for wells that are constructed to nonClass I permits by TCEQ for wells that are constructed to non--hazardous waste standards for disposal of desalination andhazardous waste standards for disposal of desalination anddrinking water treatment residualsdrinking water treatment residualsGeneral permits to authorize nonGeneral permits to authorize non--hazardous waste disposal ofhazardous waste disposal ofdesalination and drinking water treatment residualsdesalination and drinking water treatment residualsTCEQ rules addressing these provisions were adopted by TCEQTCEQ rules addressing these provisions were adopted by TCEQin June 2008, Effective July 10, 2008in June 2008, Effective July 10, 2008

TCEQ Non-Hazardous General Permit

Has not yet been adopted by TCEQWould apply only to disposal of desalination and drinkingwater treatment residualsIntended to apply also to dual permitting of Class IIdisposal wells

There are approximately 31,000 Class II wells inThere are approximately 31,000 Class II wells inTexasTexas

From UT Bureau of Economic Geology

From AECOM display of TXRRC data

Class V Injection Wells

Much faster and simpler approval processInjection must not cause pollution in the receivinggroundwater (30 TAC 331.5)

injectate is "as good or betterinjectate is "as good or better”” than receivingthan receivinggroundwatergroundwater

TCEQ has developed a list of other factors forconsideration in making the needed determinationsThis type of injection well authorization was utilized by ElPaso Water Utilities

Conclusion

Multiple options for Desalination Residual disposalOffshore DischargeOffshore DischargeInland Surface Water DischargeInland Surface Water DischargeIrrigationIrrigationSurface impoundmentSurface impoundmentDischarge to sanitary sewerDischarge to sanitary sewerUnderground InjectionUnderground Injection

Selection of an appropriate and affordable residuals managementoption is often the determining factor in project feasibility

Questions?