TDS considering desalinization plant for Edwards saline zone

Locally based waste handler Texas Disposal Systems is considering an ambitious plan to explore desalinization of water from the saline zone of the Edwards Aquifer. If undertaken, the project could also provide scientists and other interested parties a look at a possible alternative water source for a rapidly growing – and drying – region.

 

TDS would use methane gas recovered from its landfill to power the desalinization project. Such efforts are notoriously energy intensive, and the TDS approach would apparently alleviate those pressures .

 

It would all be part of a two-phase approach that would start with a research stage and end, if all works, with the construction of a desalination plant. The effort will require the passage of state legislation that will allow wells for the project. The Senate version of the legislation, carried by Senator Judith Zaffirini, D-Laredo, and its house companion, carried by Rep. Eddie Rodriguez, D-Austin, are on the Local and Consent Calendars for each respective chamber.

 

Jennifer Walker of the Lone Star Chapter of the Sierra Club was “cautiously optimistic” about the plan. Walker added that the organization supports the legislation, which would allow for monitoring of the project by academics at Texas State University, and an interim comment period that would assess any impacts it had before TDS moves forward with phase two.

 

Brian Smith, a senior hydrologist for the Barton Springs/Edwards Aquifer Conservation District was also encouraged. “From all the data that has been collected (thus far)…it seems like this has a lot of promise,” he said. “We’re fairly optimistic that this can be done but we won’t know for sure until those studies (come back).”

 

Those studies would result from the collection of data associated with the TDS effort. Smith hopes to sink both a test well and a monitoring well into the Edwards. He and his colleagues could then observe how water travels between the saline and fresh portions of the aquifer in an effort to, among other things, protect the fresh portion of the Edwards from cross-contamination with the saline zone.

 

However, Smith says that the district can only afford the costs of one of the wells. They hope to partner with TDS or another entity to cover the other.

 

Under the legislation, Texas State University would also monitor the results of the research phase of the project.

 

The TDS plan calls for processed water to be separated from its brackish elements. The brackish excess would be pumped into concrete disposal wells that would be located below the Edwards in the brackish portion of the Trinity Aquifer.

 

Walker said that the parties involved negotiated to get the draft version of the bill to a point where they all endorsed it. “We’ve been working with the district and Texas Disposal Systems to come up with language in the draft bill that we are comfortable with,” she said. “We’re all supporting the bill and supporting the project.”

 

Even if the TDS project doesn’t pan out, district spokesperson Robin Havens Gary notes that interested parties could learn a lot from the research portion of it. “It’s a very complex system over there (and) there’s a lot to be learned,” she said.