New Castle County, DE
The federal environmental record for New Castle County (population 578,592): what is on file, where it is, and what remains open. Sources and retrieval dates are on the methodology page.
15
Superfund NPL sites
32
federal cleanup sites
5
PFAS-detecting water systems
27
TRI facilities
51
open tank releases
Superfund NPL sites
| Site | City | Status | Listed |
|---|---|---|---|
| Army Creek Landfill | New Castle County | on the NPL | 09/08/1983 |
| Delaware City PVC Plant | Delaware City | on the NPL | 09/08/1983 |
| Delaware Sand & Gravel Landfill | New Castle County | on the NPL | 09/08/1983 |
| E.I. du Pont de Nemours & Co., Inc. (Newport Pigment Plant Landfill) | Newport | on the NPL | 02/21/1990 |
| East Basin Road Groundwater | New Castle | on the NPL | 03/29/2023 |
| Halby Chemical Co. | New Castle | on the NPL | 06/10/1986 |
| Harvey & Knott Drum, Inc. | Kirkwood | on the NPL | 09/08/1983 |
| Hockessin Groundwater | Hockessin | on the NPL | 05/17/2018 |
| Koppers Co., Inc. (Newport Plant) | Newport | on the NPL | 08/30/1990 |
| New Castle Spill | New Castle County | deleted | 09/08/1983 |
| New Castle Steel | New Castle County | deleted | 09/08/1983 |
| Newark South Ground Water Plume | Newark | on the NPL | 01/18/2018 |
| Sealand Limited | Mount Pleasant | deleted | 08/30/1990 |
| Standard Chlorine of Delaware, Inc. | Delaware City | on the NPL | 07/22/1987 |
| Tybouts Corner Landfill | New Castle County | on the NPL | 09/08/1983 |
Drinking water: PFAS testing
Public water systems serving New Castle with at least one PFAS detection under UCMR5. The federal limit for PFOA and PFOS is 4 ng/L; EPA proposed in May 2026 to rescind the limits for the other compounds, which are shown for information.
| System | Highest results | Reading |
|---|---|---|
| ARTESIAN WATER COMPANY DE0000552 | PFPeA: 106 ng/L PFBA: 79.1 ng/L PFHxA: 72.2 ng/L | above final limit |
| SUEZ WATER DELAWARE DE0000564 | PFBA: 40.6 ng/L PFPeA: 32.1 ng/L PFHxA: 31.7 ng/L | above final limit |
| NEWARK WATER DEPARTMENT, DE DE0000630 | PFOA: 25.3 ng/L PFHxA: 13.2 ng/L PFPeA: 12.6 ng/L | above final limit |
| WILMINGTON WATER DEPARTMENT DE0000663 | PFPeA: 32.2 ng/L PFHxA: 21.1 ng/L PFBA: 14.1 ng/L | above final limit |
| MUNICIPAL SERVICES COMMISSION DE0000634 | PFBA: 147.2 ng/L PFPeA: 122.9 ng/L | detected |
On a system with detections? Testing and treatment options
Facilities reporting toxic releases (2024)
27 facilities in New Castle filed TRI reports for 2024, totalling 4.6M lb released. The 25 largest by volume:
| Facility | City | Top chemicals | Total released |
|---|---|---|---|
| DELAWARE CITY REFINERY | DELAWARE CITY | Nitrate compounds (water dissociable; reportable only when in aqueous solution), Sulfuric acid (acid aerosols including mists, vapors, gas, fog, and other airborne forms of any particle size) | 4.3M lb |
| CRODA INC | NEW CASTLE | Ethylene glycol, Ethylene | 118k lb |
| SUN CHEMICAL | NEWPORT | Methanol, Xylene (mixed isomers) | 38k lb |
| AIR PRODUCTS & CHEMICALS | NEW CASTLE | Methanol, Ammonia | 26k lb |
| AIR LIQUIDE ADVANCED SEPARATIONS | NEWPORT | N-Methyl-2-pyrrolidone, n-Hexane | 19k lb |
| EDGE MOOR/HAY ROAD ENERGY CENTERS | WILMINGTON | Ammonia, n-Hexane | 18k lb |
| DUPONT ELECTRONIC MATERIALS CMP LLC B2 B3 B8 | NEWARK | N,N-Dimethylformamide, Diisocyanates | 16k lb |
| NEXPERA - RED LION PLANT | NEW CASTLE | Sulfuric acid (acid aerosols including mists, vapors, gas, fog, and other airborne forms of any particle size), Hydrogen sulfide | 8k lb |
| NORAMCO | WILMINGTON | n-Butyl alcohol, Toluene | 5k lb |
| VIBRANTZ MINERALS LLC | NEW CASTLE | Manganese compounds, Chromium and Chromium Compounds(except for chromite ore mined in the Transvaal Region) | 3k lb |
| AGILENT TECHNOLOGIES INC. - NEWPORT SITE | NEWPORT | Methanol, Acetonitrile | 2k lb |
| ROGERS CORP - BEAR | BEAR | Xylene (mixed isomers), Ethylbenzene | 2k lb |
| V&S DELAWARE GALVANIZING LLC | NEW CASTLE | Zinc compounds, Lead | 729 lb |
| US ARMY NATIONAL GUARD RIVER ROAD TRAINING SITE RANGE DE | NEW CASTLE | Lead | 600 lb |
| CLARIOS LLC | MIDDLETOWN | Lead And Lead Compounds | 344 lb |
| DUHADAWAY TOOL & DIE SHOP INC | NEWARK | Nickel, Chromium | 276 lb |
| DUPONT ELECTRONIC MATERIALS CMP LLC-B5 B6 | NEWARK | N-Methyl-2-pyrrolidone, Diisocyanates | 219 lb |
| OWEN STEEL CO | WILMINGTON | Manganese And Manganese Compounds, Nickel And Nickel Compounds | 20 lb |
| W L GORE & ASSOCIATES INC | NEWARK | Lead | 9 lb |
| KUEHNE CHEMICAL CO INC | NEW CASTLE | Chlorine | 9 lb |
| AEARO TECHNOLOGIES LLC | NEWARK | Toluene diisocyanate (mixed isomers), Diisocyanates | 5 lb |
| HMA CONCRETE LLC DBA HERITAGE CONCRETE HEALD STREET FACILITY | WILMINGTON | - | 0 lb |
| VP RACING FUELS | NEWARK | Lead compounds | 0 lb |
| COLOR WORKS PAINTING INC. | NEW CASTLE | - | 0 lb |
| HMA CONCRETE LLC DBA HERITAGE CONCRETE MIDDLETOWN FACILITY | TOWNSEND | - | 0 lb |
Underground fuel tanks
EPA's UST Finder records 1,460 tank facilities in New Castle: 616 tanks in service and 4,027 closed. 3,072 fuel releases are on record, of which 51 remain open. Open releases are cleanups that have not reached "no further action".
Radon
EPA maps New Castle as Zone 2, moderate predicted indoor radon (2 to 4 pCi/L average). Radon and air quality are covered in depth on lung.com.
The record for one specific address
County figures blur what matters: distance. The Address Environmental Report runs these same federal datasets against one address and reports every site, tank, polluter and water result around it, with distances, in about a minute.
Get the report - $39All federal cleanup sites on file
The wider Superfund enterprise inventory (SEMS) for New Castle, including sites assessed but never listed. Presence here records that EPA had reason to look, not a finding of danger.
- 626 GARASCHES LANEWILMINGTON
- 700 A STREETWILMINGTON
- ANY GARMENT CLEANERS #106WILMINGTON
- ARMY CREEK LANDFILL/LLANGOLLEN LANDFILLNEW CASTLE
- BRANDYWINE CHEMICAL CO.NEW CASTLE
- DELAWARE AIR NATIONAL GUARDNEW CASTLE
- DELAWARE CITY PVC PLANTNEW CASTLE
- DELAWARE SAND & GRAVEL LANDFILLNEW CASTLE
- E I DUPONT DE NEMOURS - HOLLY RUN PLANTNEWPORT
- EAST BASIN ROAD GROUNDWATERNEW CASTLE
- FORMER SUNG CLEANERSWILMINGTON
- GENERAL CHEMICAL CORPORATION (CLOSED)CLAYMONT
- GOVERNOR BACON HEALTH CENTERDELAWARE CITY
- HARVEY & KNOTT DRUM, INC.KIRKWOOD
- HOCKESSIN GROUNDWATERHOCKESSIN
- KOPPERS CO., INC. (NEWPORT)NEWPORT
- LEAD CABOOSEHOCKESSIN
- LIBERTY CENTERWILMINGTON
- METAL-TECH, INC.NEW CASTLE
- NEW CASTLE AIR NATIONAL GUARD 1664 TAG FACNEW CASTLE
- NEW CASTLE COUNTY AIRPORTNEW CASTLE
- NEW CASTLE RIFLE RANGE TRAINING SITENEW CASTLE
- NEW CASTLE SPILLNEW CASTLE
- NEW CASTLE STEELNEW CASTLE
- NEWARK SOUTH GROUND WATER PLUMENEWARK
- NEWPORT DRUM SITENEWPORT
- NVF COMPANY INC - YORKLYN FACILITYYORKLYN
- RECYCLERS OF DELAWARE DRUM SITENEW CASTLE
- SEALAND LIMITEDMIDDLETOWN
- STANDARD CHLORINE OF DELAWARE, INC.DELAWARE CITY
- TYBOUTS CORNER LANDFILLNEW CASTLE
- US CORP OF ENGR CANAL SITESAINT GEORGES