Socioeconomic disparities and regional trends in United States landfill tipping fees.

Landfill tipping fees influence the affordability and sustainability of municipal solid waste (MSW) management across the U.S. Past studies have often focused on single years or specific regions, leaving a limited understanding of long-term spatial and temporal disparities. This study analyzed consumer price index-adjusted tipping fees (2024 USD) for all 50 states from 2016 to 2024. Using the Jenks natural breaks method, states were grouped into Low (<$51/ton), Medium ($51-$70/ton), and High (>$70/ton) categories. These groups showed clear geographic patterns, with High-fee states concentrated in the Northeast, Medium-fee states more dispersed, and Low-fee states largely in the South. Average fees were $45.2/ton (Low), $57.3/ton (Medium), and $93.1/ton (High). The Northeast recorded the highest nominal fee growth (38.6%), compared to 17.6% in the South. Temporal analysis also revealed widening disparities, with High-fee states displaying greater variability and negatively skewed distributions, indicating underlying structural pressures driving cost extremes. A global Moran's I statistic of 0.37 and p = 0.013 confirmed significant spatial clustering. Regression analysis showed a strong income-fee relationship in the Medium group (R2 = 0.733) but weak associations in the Low (R2 = 0.155) and High (R2 = 0.063) groups. These findings offer data-driven insights to support more equitable and sustainable landfill pricing policies.