pfas · Cattaraugus County
Oregon Road Site
Olean
A vacant piece of Olean's former refinery landscape held tens of thousands of tons of petroleum-affected soil and a concentrated PFAS area beside Two Mile Creek, leading to excavation, in-place stabilization, and an underground carbon barrier.
The documented story
What happened here?
The 24.57-acre Oregon Road property is a vacant northern piece of Olean's former oil-refinery landscape. Refining operated in the surrounding legacy complex under several names from about 1880 into the 1950s, and this parcel had been vacant since roughly 1960. Buried refinery piping and widespread petroleum-affected fill survived long after the buildings disappeared.
Two Mile Creek, a tributary of the Allegheny River, crosses the southeastern part of the site. Homes lie across Oregon Road to the northeast, with commercial and undeveloped land on the other sides. That setting made both contaminated-soil contact and groundwater migration important parts of the brownfield investigation.
Investigators found mobile petroleum, staining, and odors in grossly contaminated soil, plus weathered petroleum across a still larger volume. PAHs and arsenic exceeded commercial-use soil criteria in selected surface areas. PFAS sampling then identified a more concentrated area in soil and groundwater near three monitoring wells on the southwest side.
The records document PFOA, PFOS, and other PFAS, but they do not identify this land as a PFAS manufacturing plant or prove what historical product introduced them. The refinery history explains the petroleum problem; the PFAS source should remain described as unresolved unless later evidence identifies it.
Chronology in context
Turning points in the public record
About 1880–1950s
Oil-refining operations occupied the larger legacy-site landscape at Olean, with pipelines and petroleum handling extending through and around the future Oregon Road parcel.
About 1960 onward
The Oregon Road property remained largely vacant while subsurface refinery piping, petroleum-affected soil, and fill stayed in place.
2017–2019
Brownfield investigations sampled soil, groundwater, surface water, sediment, and vapor. State-required emerging-contaminant sampling identified PFAS in a defined southwestern area.
June 2020
DEC selected a commercial-use remedy combining mass excavation, PFAS soil stabilization, an underground activated-carbon barrier, a site cover, and enforceable land and groundwater controls.
2020–2021
Crews removed about 33,600 tons of grossly petroleum-affected soil, about 800 tons of PAH-affected soil, and approximately 4,100 linear feet of former refinery piping.
December 2021–January 2022
DEC approved the final engineering report and issued a Certificate of Completion after construction of the remedy.
2023–2025
Annual periodic reviews documented inspection and performance of the cover, groundwater barrier, monitoring program, and institutional controls.
Atlas classification: environmental detection, agency investigation.
PFAS activity, investigation, or detection is documented in the cited site record. That documentation does not by itself establish off-site exposure or a health effect in any individual.
Compounds and evidence
Detected
Medium: soil and groundwater
Detected
Medium: soil and groundwater
Detected
Medium: surface soil
DEC reported multiple PFAS compounds and total PFAS, but the decision summary names PFOA and PFOS individually.
Evidence limit: The detections do not establish PFAS production or identify APFO as the original material released.
C8 and APFO: PFOA is often called C8. APFO is the ammonium salt of PFOA, but a PFOA environmental result does not identify APFO as the original product or prove where it came from.
News record
Major news events
Coverage selected here marks a turning point in public awareness, policy, enforcement, employment, or cleanup. Links open at the original publisher or archive; WNYAtlas does not reproduce restricted articles or images.
Olean brownfield earns completion certificate after a 34,000-ton excavation
DEC certified a commercial-use cleanup after removal of petroleum- and PAH-affected soil and old refinery piping, treatment of PFAS-affected soil, and installation of an activated-carbon groundwater barrier. Long-term cover, land-use, and groundwater controls remain part of the remedy.
New York State Department of Environmental Conservation ↗Chemical guide
Chemicals named in this record
These links explain potential hazards and exposure pathways. A chemical named in a record does not establish that anyone was exposed or harmed.
Health context
Why PFAS are a long-term concern
PFAS are a large family of manufactured chemicals. Many are highly persistent, and some can remain in the environment or build up in people and animals over time. Persistence can allow releases to move through groundwater, surface water, waste systems, food, and fish long after the original use has ended.
Human studies have found associations between increased exposure to certain PFAS and higher cholesterol, lower antibody response to some vaccines, changes in liver enzymes, pregnancy-induced hypertension and preeclampsia, small decreases in birth weight, and kidney or testicular cancer for PFOA. Evidence differs by compound, and research continues. A site detection does not show that a particular person was exposed or that PFAS caused an illness.
Environmental record
Documented impacts
- The 2020 decision estimated approximately 20,000 cubic yards of grossly contaminated petroleum soil and another 33,600 cubic yards showing weathered petroleum impacts before final excavation quantities were established.
- PFOA and PFOS were detected in surface and subsurface soil in the targeted area. Groundwater reached 100 parts per trillion PFOA and 1,020 parts per trillion PFOS under the screening levels used in the 2020 decision, and DEC expected off-site groundwater migration near the downgradient property boundary.
- PFAS leaching tests showed that water could mobilize compounds from some surface soil. That finding led to in-place stabilization of approximately 1,700 cubic yards and a groundwater interception barrier rather than reliance on a surface cover alone.
- Two Mile Creek water and sediment were sampled. The 2020 decision reported limited chemical findings in those samples and did not present the creek as a demonstrated community-wide PFAS exposure pathway from this parcel.
- Filtered groundwater results did not confirm the elevated metals seen in turbid unfiltered samples, an important quality distinction that prevents the metals results from being overstated.
Response
Cleanup and controls
- Excavated petroleum and PAH material went to approved off-site disposal, old refinery piping was removed, and clean fill was placed to restore grades.
- In-situ stabilization bound PFAS in affected surface soil to reduce leaching. Along the downgradient boundary, injected liquid activated carbon formed a permeable treatment barrier intended to capture PFAS moving with groundwater.
- A demarcation layer and soil cover separate people from residual contamination. An environmental easement restricts the property to approved uses, prohibits uncontrolled groundwater use, and requires compliance with the site-management plan.
- The Certificate of Completion means the approved commercial-use remedy was constructed; it does not mean all contamination was removed. Periodic certification, inspection, groundwater monitoring, maintenance of the cover and barrier, and state enforcement remain necessary.
Then and now
The site today
Oregon Road is a completed Brownfield Cleanup Program site managed for commercial use. The 2025 periodic-review file is the newest item in DEC's repository; redevelopment remains subject to the environmental easement, groundwater restriction, cover system, activated-carbon barrier, and continuing monitoring.