Messmer has worked as an environmental consultant has focused on the evaluation, design, development, and implementation of conventional and innovative in-situ and on-site technologies for remediation of contaminated sites. She has consulted businesses, banks, and the U.S. government on the presence of environmental contaminants. Messmer has conducted and managed projects ranging in scale from small hazardous waste site assessments and remediation design, to large remedial investigations and remedial action under a variety of regulatory programs including RCRA, CERCLA, and State Superfund. Messmer served on then-Governor Maggie Hassan’s Task Force to investigate the rhabdomyosarcoma and pleuropulmonary blastoma double pediatric cancer cluster that she identified and reported in 2014. The cluster was confirmed by the NH Department of Health and Human Services in 2016. She was appointed head of the Governor’s Task Force Subcommittee to coordinate efforts with the USEPA and New Hampshire Department of Environmental Services to direct the investigation into Coakley Landfill Superfund Site.
Messmer's three bills signed into law in 2017 include which established a commission on the Seacoast cancer cluster investigation, which established a commission to study long-term goals and requirements for drinking water in the Seacoast area, and which established a commission to study environmentally-triggered chronic illness. House Bill 485, which addressed the need for standards for emerging contaminants in drinking water was opposed by the Business and Industry Association. House Republican members from Merrimack and Hudson, New Hampshire, where the Saint Gobain corporation contaminated drinking water in three towns including Merrimack, Litchfield and Bedford, walked away from the Committee of Conference and refused to return. In January 2017, Messmer and Rep. Renny Cushing, founders of Greenland Safe Water Action and Testing for Pease, founded New Hampshire Safe Water Alliance. For the 2018 session, Messmer has authored an Anti-Hate Resolution in response to hate crimes in the state and legislation authorizing for state regulators to take action to address an imminent hazard associated with surface water contaminated by an aged Superfund Site.
Messmer is a longtime resident of Rye, New Hampshire, where she lives with her husband and two teenage sons. She is a blogger and writes for the Less Cancer Journal. She is a member of the National Writers Union and is the author of several academic publications.
