EAST PALESTINE — Sediment and surface water samples collected during the latest reassessment of Sulphur and Leslie Run are still “under evaluation,” Norfolk Southern recently reported, but according to sheen charts that can viewed at EPA.gov, waterways remain impacted by the 2023 train derailment, although that impact is decreasing.

Data available by clicking the “Qualitative Sheen Assessment Results” tab on the EPA’s derailment website, indicates that visible sheen had reduced significantly since the first assessment in December of 2023 but was still present in portions of both waterways in April.

According to the interactive charts, heavy sheen was still observed in April in a segment of Sulphur Run that flows just west of James Street and to Leslie Run. Medium sheen was also identified in that portion. In the part of Sulphur located east of James Street, small amounts of heavy and medium sheen were also recorded. The charts indicate that Leslie Run had areas of medium sheen in the upper portion (where Sulphur feeds into it near the East Palestine City Park entrance) while the entirety of Leslie Run (all the way to Bull Run Creek) had spots of light sheen.

The EPA first ordered Norfolk Southern to investigate sheen in both waterways in October of 2023 under the agency’s authority granted by the Clean Water Act. Both the EPA and the railroad called the investigation a “qualitative assessment.” The EPA-approved process involved agitating the stream sediment and turning over rocks and then grading sheen uncovered on a scale of 0-3 — 0 being no sheen visible and 3 being heavy sheen.

Since the derailment, the village creeks have undergone a series of remediation practices and procedures. They include oxygenation and air-knifing (a process where air is injected into the sediment to liberate anything under the sediment and bring it to the surface to be later collected by a booming system downstream), as well sediment washing and high-pressure washing of the culverts in an attempt to remove contaminated sediment that was suspected of contributing to indoor air odors in some area homes and businesses in the immediate months following the rail disaster. Sediment sampling and pore water sampling — a process the EPA describes as collecting water from sediment using a peristaltic pump or a syringe — have also been conducted as part of the surface-water remediation.

In other clean-up updates, site restoration is still expected to be “substantially complete by early/mid-June” and air monitoring continues in “areas of active operations” and “as site activities continue to diminish the associated air monitoring will also be reduced accordingly.”

Norfolk Southern also reported “ongoing monitoring of surface water, groundwater, and drinking water wells continues per the schedules defined in the associated work plans” and said that includes “East End wetland water and sediment sampling efforts approved by the EPA.”

Additional monitoring wells were installed in the wetland area in late March and spot excavations completed to remove 2-butoxyethanol — a full tanker or 25,000 gallons of the chemical used as solvent in the paint industry was spilled during the derailment — but no other updates regarding the remediation process related to that area of the site have been recently released.

(Elverd can be contacted at selverd@mojonews.com)