Work

Repurposing Enhanced Rock Weathering for Cationic‐Metal Stabilization: A Nature‐Based Protocol for Contaminated‐Soil Remediation

Year: 2026

Type: article

Abstract: ABSTRACT Many brownfield, mining, urban‐fill, and legacy agricultural sites contain cationic metals in shallow soil, where they pose direct‐contact, plant‐uptake, and leaching risks. This study formalizes and operationalizes established silicate‐rock stabilization chemistry as a nature‐based remediation protocol grounded in enhanced rock weathering. Prior studies show that silicate‐rock amendments can alter cationic‐metal lability, plant uptake, and leaching, while performance varies with soil, contaminant, feedstock, dose, hydrology, and time. However, to our knowledge, this treatment concept has not been developed into a complete remediation protocol that integrates natural‐silicate feedstock qualification, carbonate–silicate blend and dose calibration, placement throughout the contaminated interval, and verification against governing regulatory leaching criteria. Remedy reliability is the central design objective: by pairing rapid carbonate‐driven pH control with a bank of weatherable silicate minerals that supplies residual acid‐neutralizing capacity, the protocol is designed to increase the likelihood of successful treatment, sustain immobilization as soil conditions change, and support different sites and remedial objectives, including those where preserving soil function is important. It screens feedstocks for mineralogy, molar Mg:Si, reactive Fe–Al, and total and leachable trace metals and verifies both target and feedstock‐derived metals. Earlier remediation studies and two watershed‐scale studies inform the protocol. A basalt trial in a Vermont agricultural catchment documents near‐term changes in metal lability and responses along hydrologically connected flow paths, while public lysimeter records from wollastonite‐treated Hubbard Brook Watershed 1 in New Hampshire document low dissolved Al concentrations persisting for over 25 years. Application of the protocol should proceed through site‐specific bench and pilot‐treatability testing to calibrate dose and performance and verify whether the achieved stabilization meets the applicable remediation criteria using the methods required for each relevant exposure pathway.

Source: Remediation Journal

DOI: 10.1002/rem.70085

Author: Quinn C. Zacharias

Institution: Yale University

Language: English

Topic: Heavy metals in environment

Subfield: Pollution

Field: Environmental Science

Domain: Physical Sciences

SDG: Life on land

Open Access status: hybrid

Estimated APC paid: $3,460