Superfund / NPL site · EPA Superfund SEMS through latest publishNPL Final

Avco Lycoming (Williamsport Division)

This site is currently on the EPA Superfund National Priorities List and remains under federal cleanup oversight. Most-cited contaminant of concern: 1,2-Dichloroethene (Cis And Trans Mixture).

652 Oliver St, Williamsport, Pennsylvania · ZIP 17701 · EPA ID PAD003053709

CLEANUP TIMELINE

Listing-date and cleanup-phase enrichment from EPA's per-site SEMS profile is queued for a follow-up ingest pass. Until then, this section will populate from EPA's published timeline data.

Anomaly engine

Notable Signals

No notable signals at this Superfund site for the current ingest. Cleanup-phase and SEMS-action flags are deferred to a follow-up engineering pass.

Contaminants of concern · per EPA SEMS

What's In This Site

Each row pairs a contaminant with the medium it was found in (the exposure pathway). Hover any named contaminant for an agency-cited health-risk summary. Cited count = number of SEMS decision records (RODs and related) that name the pair.

ContaminantPathwayCited
1,2-Dichloroethene (Cis And Trans Mixture)Groundwater3
Chloroethene (Vinyl Chloride)Health riskIARC Group 1 carcinogen — angiosarcoma of the liver. Final TCE/PCE biodegradation product; commonly found in groundwater plumes. EPA MCL 2 µg/L. (IARC, EPA)Groundwater3
TrichloroetheneHealth riskTCE. IARC Group 1 carcinogen — kidney cancer; suspected liver cancer and non-Hodgkin lymphoma. EPA MCL 5 µg/L; common DNAPL groundwater plume contaminant. (IARC, EPA, ATSDR)Groundwater3
CadmiumGroundwater2
BariumHealth riskSoluble barium compounds are toxic if ingested, affecting the heart, kidneys, and nervous system. Insoluble forms (e.g. barium sulfate) are far less toxic. (EPA)Groundwater1
Chromium(Vi)Health riskHexavalent chromium (Cr-VI) is an IARC Group 1 carcinogen via inhalation, causing lung cancer; trivalent chromium is far less toxic. (IARC, EPA)Groundwater1
ManganeseHealth riskExcess inhalation can cause manganism, a Parkinson-like neurological disorder. (ATSDR)Groundwater1
Drinking-water linkage · SDWIS

Groundwater Systems Serving Communities Within 3 Miles

The 5 systems below draw on groundwater (or mixed sources) and serve communities whose centroid sits within 3 miles of this site. Distance is to the served-city centroid — SDWIS does not expose individual wellhead locations, so this is a proximity screen, not a wellhead-impact assessment.

Water systemServesDistancePopulation servedSourceStatus
American Tempo Village Park PrivateWilliamsport0.4 mi88GROUNDWATERUNRESOLVED
Oak Lynn Manor Mobile Home Pk PrivateWilliamsport0.4 mi250GROUNDWATERUNRESOLVED
Foxcroft Manor Mobile Home Pk PrivateWilliamsport0.4 mi200GROUNDWATERUNRESOLVED
Collomsville Mutual Waterworks PrivateWilliamsport0.4 mi250GROUNDWATERUNRESOLVED
Loyalsock Mobile Home Park PrivateSouth Williamsport2.3 mi85GROUNDWATERUNRESOLVED

Methodology: served-city centroid (TIGER 2020) is used as the PWS coordinate. Source-water classification from SDWIS primary_source_code; only groundwater and mixed-source systems are queried. Click any system above for its full SDWIS profile.

Equity context · ACS 2018-2022 block-group demographics

Who Lives Near This Site

Within 1 mile of this site (10 Census block groups, population-weighted demographics): a population of 8,391. Why we surface this →

POPULATION SHARE
51.4%

Low-income

POPULATION SHARE
17.4%

People of color

POPULATION SHARE
2.9%

Under age 5

POPULATION SHARE
16.4%

Over age 64

Source: Census ACS 2018-2022 block-group demographics, population-weighted across the 1-mile buffer around this site (from USEPA-clone/EJAM-open blockgroupstats). NPL site proximity contributes to the national EJ pattern; indicator-level percentile and disparity scores are surfaced on the county page and the state page.

Source. EPA Superfund Enterprise Management System (SEMS) · retrieved 2026-05-07. SEMS is a federal public-domain dataset under 17 USC §105.

What this is not. We report EPA's published Superfund record — site listing, status, and contaminants of concern as named in EPA's decision documents. We do not perform site visits, independent air or water sampling, or current-state health-risk assessment. NPL listing reflects EPA's Hazard Ranking Score at a point in time; it does not by itself describe present-day exposure.