By: Jack Money – The Oklahoman – Oklahomans are about to gain access to additional groundwater that can be used for industrial, commercial, agricultural and (to a limited extent) domesticated purposes.
On Tuesday, members of the Oklahoma Water Resources Board adopted proposed rules allocating ownership of marginal, brackish groundwater to surface owners, allowing for its production and use for beneficial purposes.
Its intent primarily is to provide the oil and gas industry with an additional source of water it could use to drill and produce horizontal wells.
However, it also opens up the water’s use for other agricultural and commercial purposes — an important step toward making Oklahoma more self-sufficient for water use in coming decades.
The permitting process follows the same basic regulatory framework the board historically used to govern how freshwater allocations are made.
The rules, which still must be accepted by Oklahoma’s legislature and governor, are yet another transitional step the agency is taking to address past oil and gas industry requests to tap the source.
Marginal water isn’t water produced as part of oil and gas operations. The Oklahoma Corporation Commission regulates that water, which already is often recycled and reused for well completion operations.
Instead, marginal water includes underground formations of brackish water with total dissolved solids rates between 5,000 and 10,000 parts per million.
Marginal water formations typically are deeper than freshwater tables, but aren’t deep enough to be considered part of oil and gas formations.
They must also be protected from contamination by oil and gas drillers, the same as freshwater tables that typically have total dissolved solids rates between 0 and 5,000 parts per million (any “fresh” groundwater with a total dissolved solids rate of greater than 500 parts per million requires some measure of treatment to make it potable).
Two key pieces of legislation approved in past years gave the board the authority to move forward with its plans, officials said.
The first, co-sponsored by Sen. Eddie Fields, R-Wynona, and State Rep. Weldon Watson, R-Tulsa, gave the board the authority to regulate groundwater with total dissolved solids between 5,000 and 10,000 parts per million.
A second bill, co-authored by state Rep. Kenton Patzkowsky, R-Balko, and Sen. Casey Murdock, R-Felt, provided the board the statutory authority to oversee the production of groundwater with total dissolved solids of between 5,000 and 10,000 parts per million for beneficial uses.
Rules adopted by the water resources board in 2018 established construction standards for wells designed to produce marginal water and also set up a new category for marginal water drillers that requires them to undergo additional training.
While these latest rules allow for marginal water’s production and use, officials said this month they don’t expect to see a tidal wave of applications.
“We have a lot of work to do,” said Kent Wilkins, the board’s planning and management chief, noting the rules create a process the agency intends to follow to map brackish water tables for future production.
What could make it tricky, he said, is that brackish water formations mimic their oil and gas counterparts because they differ in reserve capacities and porosities impacting production rates.
The best source of information on where adequate zones may exist are logs generated by oil and gas operators on previously drilled and completed wells.
“Part of our project would be to put together whatever data is out there, because every basin probably is a little bit different,” he said.
Another reason Wilkins doesn’t expect to see many applications right away is because oil and gas drillers now prefer to use recycled, produced water to handle their well drilling and completion needs.
Jim Roberts, a senior hydrogeologist with CP&Y Inc., in Oklahoma City, said Tuesday he agrees with Wilkins’ expectations.
“Right now, the ponds and everything are full — there is plenty of surface water out there,” Roberts said, adding applications to use brackish water could climb “if we get into a drought and those resources are no longer available.”
Regardless of immediate demand, however, Wilkins stressed the rule changes are important because they enable the agency to move forward with programs designed to help it meet required water usage rates established by the Water for 2060 Act, approved by Oklahoma’s Legislature in 2012.
The act mandated for Oklahoma to be using no more freshwater in 2060 than it did in 2012.
The board aims to meet that requirement through continued conservation efforts that include recycling some sources of water and using marginal quality water as well.
“Today, there are limited uses for marginal waters,” Wilkins said. “But 50 years from now, we believe treatment technologies will be there and we’ll have many more opportunities for its use.”