University of Iowa,
J.D., with Distinction, 2001
Washington University in St. Louis,
B.A. in Political Science, with College Honors, 1998
W. Alfred Hayes Award, 1998
Academic All-American Second Team, 1997
Missouri
Illinois
Bar Association of Metropolitan St. Louis
Chair, Environmental & Conservation Law Committee, 2011-2013
Air Liquide
MilliporeSigma
PolyOne
Gander Mountain Company
Environmental Operations
Alberici Constructors
Lillibridge Healthcare Services
Flat Branch Mortgage
Listed in The Best Lawyers in America (by BL Rankings) for Environmental Law, 2024-2025
Named to "Missouri Lawyers Weekly" Power List for Environmental & Energy Law, 2022-2023
Included in Missouri & Kansas Super Lawyers Rising Stars list, 2009-2015 (by Thomson Reuters)
Missouri Lawyers Weekly Up and Coming Lawyer, 2008
Thompson Coburn LLP
Partner, 2010-Present
Associate, 2001-2009
Paul is a highly effective litigator and regulatory compliance attorney who has resolved environmental and real estate/construction disputes in state and federal courts across the country.
In his environmental work, Paul counsels clients on groundwater and surface water issues, soil contamination and permit evaluations and transfers for the mining industry, chemical and plastics manufacturers and landfill operators. In court, he has both prosecuted and defended CERCLA contribution and cost recovery lawsuits, litigation under the Missouri "Spill Bill," cases involving Illinois Environmental Protection Act, the federal Clean Water Act and the Missouri Clean Water Law, as well as common law tort actions and contract disputes. In his compliance-side work, Paul has represented clients before and negotiated with the EPA, the Missouri DNR, the Illinois EPA, the U.S. Department of the Interior Office of Surface Mining and the Illinois DNR.
Paul works hard for clients to resolve matters both in court and during administrative proceedings. He participates in every facet of negotiation and litigation, including trying cases in court and before administrative hearing officers, arguing complex motions, representing clients during mediations and preparing and arguing appeals. He also successfully excluded expert testimony in numerous cases through strategic Daubert challenges.
Paul has special experience in permit transfers that are required when a client embarks on company and facility acquisitions. He evaluates the permits, monitors the deadlines to submit requisite paperwork and assists clients in preparing the necessary forms and notifications. Together with his permit team, Paul has handled permit transfers in 17 different countries and over 35 states.
In his real estate and construction work, Paul prosecutes and defends eminent domain lawsuits, commercial lease disputes and complex construction cases. He has handled soil, materials and grading defect claims as well as light rail construction projects and property acquisitions through condemnation. Paul has significant experience in commercial lease disputes on behalf of both landlords and tenants concerning rent disputes, maintenance obligations and additional rent and common area maintenance calculations.
Paul has been a strong advocate for all aspects of his clients' mining operations and environmental compliance, serving as the primary litigator and regulatory compliance counsel for multiple national coal mining companies for over 15 years. In 2015, he successfully sought intervention in a citizen's suit case brought against the federal Office of Surface Mining, which was an attempt to upend ongoing reclamation operations at a client's mine. In 2012, Paul successfully represented a client before the Illinois Supreme Court when its mine permits were being challenged directly and indirectly. In 2010, he successfully obtained summary judgment in an administrative hearing brought by petitioners who wished to shut down a coal mine due to allegations of environmental non-compliance.
As an outgrowth of his work defending property owners at CERCLA sites, Paul has been the primary litigation counsel for several environmental contractors. He assists clients in developing sophisticated legal strategies that maximize the prospect of a favorable outcome. In 2015, Paul successfully resolved a more than four-year-long case involving allegations of improper disposal of solid waste material. The case raised CERCLA claims and common law causes of action, and involved numerous property owners, developers, banks, contractors and subcontractors.
Paul acts as the primary permit evaluation and transfer attorney for many acquisitions both nationally and internationally. His projects and matters have covered 17 foreign countries and a majority of the states. He has put together a team of attorneys and environmental technical advisors that act as a "one-stop shop" for clients who need to transfer facility permits in the environmental, health and safety field.
Paul has served as the primary litigation counsel on large construction defect cases for national retailers, contractors, architects and engineers all over the United States. In 2016, he successfully settled a multi-million dollar lawsuit involving allegations of soil and structural defects. The matter involved many contractors, subcontractors and insurers, which complicated discovery, motion practice and negotiations. But Paul devised a strategy to overcome these obstacles and deliver a great result for his client.
Due to his court and trial experience, Paul is a "go-to" attorney for commercial landlords looking to oust problematic tenants and for tenants who want to exit problematic leases. He handles demands letters, presses these cases quickly and forcefully through the state courts and achieves decisive results for his clients.
Federal Trade Commission to seek comments on Proposed Updates to its “Green Guides”
Supreme Court expands reach of Clean Water Act to cover some discharges to groundwater
EPA formalizes approach to avoid federal and state duplication of inspections and enforcement
Environmental deregulation under President Trump: Business as usual?
New circuit split raises questions about ‘permit shield’ defense in Clean Water Act cases
Do you need a Section 404 permit for your real estate development?
Ryan Russell Kemper and Paul Sonderegger Named to Environmental & Energy Law Power List
St. Louis Boys & Girls Club announces plans for youth golf facility at former Superfund site
Thompson Coburn’s Environmental practice group celebrates top rankings
Paul Sonderegger appointed chair of environmental law committee for St. Louis bar
Thompson Coburn wins Illinois Supreme Court victory for ExxonMobil Coal
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