Missouri 2026 Legislative Session in Review

May 20, 2026May 20, 2026 News

This Missouri Legislative session was marked by several emerging environmental issues. The nationwide proliferation of AI hyperscale data centers sparked 6 bills in the Missouri Legislature, with regulatory frameworks proposed by both houses and both parties. For the first time, legislators considered the State’s failure to address its 29 abandoned landfills. The House General Laws Committee heard testimony on a ban of the pesticide Paraquat. 

Legislators faced an uphill battle having their bills referred to and heard in committee. One assessment from the Missouri Scout showed that by May 1, 60% of House Bills had not been referred to committee, while less than half of Senate bills referred to committee had a hearing. 

MCE did not get our favored priority legislation across the finish line. However, we are proud to announce that we blocked multiple harmful environmental bills and participated in negotiations on emerging topics that we expect to continue next session. Here is a breakdown of our wins and losses this session. 

Defensive Wins

Solar Moratoria

This session, the Legislature considered four bills that would have placed a moratorium on (SB 849, SB 933, HB 2477) or heavily restricted (SB 879) utility scale solar in Missouri. These pieces of legislation fly in the face of recent polling which revealed that 57% of Missourians support an 100% transition to renewable energy by 2050. These bills were based on false claims that the solar industry is unregulated and unsafe. In reality, solar development in Missouri is already subject to rigorous oversight, with the Department of Natural Resources administering a permitting process for solar facilities and the Public Service Commission conducting months-long examinations of proposed energy projects. These bills were widely opposed, not only by environmental groups, like us, but by utilities too. This is because renewable energy remains the cheapest and fastest to build form of energy available. New utility-scale solar costs just 30% of a new gas plant.

Only the Senate bills were granted hearings, during which MCE staff, members, and allies provided testimony against them. Though both SB 849 and SB 879 were voted out of the Senate Commerce, Consumer Protection, Energy, & Environment Committee, none of these harmful bills passed. 

Bayer’s Pesticide Litigation Ban

For the third year in a row, Bayer backed legislation (SB 1005 and HB 2712) to protect itself from litigation holding them liable for instances of cancer likely caused by use of the herbicide RoundUp. Effectively, these bills shield Bayer from lawsuits claiming that the company “failed to warn” RoundUp users of its potential health harms. This fight extends to multiple state legislatures, but Missouri is especially significant because Bayer is headquartered and registered here. As a result, lawsuits from around the country are litigated in Missouri. Legal immunity legislation here would therefore have a major impact on the nationwide battle.

Of the two bills introduced, only SB 1005 received a hearing. MCE testified against the bill along with several other groups, while Bayer and big ag interest groups testified in favor. Immediately following its hearing, the Senate Agriculture Committee voted to pass SB 1005 out of committee, but the bill was defeated through never being scheduled for floor debate, revealing internal opposition. 

In another significant win, Members of Congress stripped similar language from the federal farm bill. We are still awaiting a US Supreme Court decision in Monsanto v. Durnell, a Missouri-based court case that will determine whether or not Bayer can continue to be sued when they fail to warn pesticide users of their product’s risks if they comply with federal labelling laws. 

Partial Victories

Abandoned Landfills

The state’s failure to address one particularly egregious abandoned landfill–the Generally Landfill in Franklin County–sparked legislation sponsored by Senator Brown (R., 26). Senate Bill 1586 would have explicitly provided DNR the authority to remediate the landfills, but the original language slashed our state’s critical Solid Waste Management Districts’ budgets to do so. MCE participated in negotiations to avoid that eventuality while still addressing the abandoned landfills. In its final form, the bill would have reallocated 10% of the tonnage fees from the Solid Waste Management Districts to DNR for investigation and remediation of abandoned landfills across the state, updated landfill sale disclosure language, and given DNR the explicit authority to clean up these sites. 

Although the bill passed the Senate, it was not brought before the House for a vote. Senator Brown testified that he was promised an Interim Joint Committee this summer to convene stakeholders and encourage collaborative discussions aimed at identifying solutions and sustainable funding sources to address the abandoned landfill issue. We look forward to continuing to share our concerns and recommendations as these discussions move forward.

SB 953

On the last day of session, the legislature passed SB 953, a mixed-bag environmental bill. Its original version allocated 5% of sales and use tax revenue from electric power distribution to the Air Pollution Control Program within DNR. It also mandated that any extra funds allocated to DNR subaccounts roll over at the end of the year rather than reverting back to general revenue. This fills a funding gap that would have left DNR out of compliance with EPA if unfilled. MCE supported the legislation as originally filed.

However, in the last week of session, a problematic amendment was tacked onto the bill which strips DNR of its ability to create permits for any type of agricultural contamination not explicitly listed as point source pollutant. This was unnecessary because agricultural storm water discharges and return flows are already exempt from permitting requirements, effectively covering all nonpoint sources. The amendment puts several permit frameworks at risk, including the recently promulgated regulatory framework created at MCE for Denali and similar polluters. As we anticipate the fallout from this bill, we remain committed to defending permit frameworks from being rolled back. 

Losses this Session (and goals for the next!)

Of our favored priority bills, most never got a hearing. This includes our bills to ban PFAS-containing AFFF firefighting foam (HB 2270, HB 1925, SB 1725) our statewide mining permit framework (HB 2737), and three bills protecting renters and property owners from radioactive nuclear weapons waste (HB 3071, HB 2725, HB 1969). 

Our bill to restore a majority of public seats to Missouri’s Clean Water Commission (SB 960, HB 3295) received a hearing on the Senate side, but was voted down after much delay. 

Data Centers: An Emerging Issue

This session, legislators across chambers and parties introduced 6 pieces of legislation to regulate data centers in the state. They varied in their enforceability, their thresholds for what would be considered a “hyperscale” data center, and the level of protection they offer for the environment, human health, and ratepayers’ wallets. Our favored legislation was HB 3390 introduced by Rep. Scott Cupps (R., 158), which would have defined “hyperscale” data centers as those using 25 MW or more of electricity and provided robust protections from hyperscalers for Missourians. These included prohibiting hyperscalers on agricultural and conservation lands, robust setback and landscaping requirements, limited water usage, and strong noise control measures. 

Of the bills introduced, two had a hearing: HB 3362, sponsored by Rep. Colin Wellenkamp (R, 105), and HB 3364, sponsored by Rep. Mike Costlow (R, 108). Though they received overwhelming support from the public, chairman Jeff Farnan (R., 1), whose district is courting a $4 billion data center project, refused to put them up for a committee vote, effectively killing the legislation. 
Meanwhile, municipalities across the state are passing their own regulations, including the nation’s first permanent ban on all data centers in St. Charles. With such bipartisan popular opposition, we expect these statewide frameworks to be refined and re-introduced next session.

With a significant spotlight on emerging environmental issues like data centers, we look forward to working with legislators to re-introduce our priority bills, find common ground across parties, and get legislation across the finish line. Thank you to all our members and allies who made a call, sent an email, testified on a bill, and shared our calls to action. Every member makes our work possible. We hope you’ll continue to support our legislative work next session!