Mazzaro - McKees Rocks Landfill HSCA Site
Municipality: Kennedy Township, Allegheny County
Hazardous Sites Cleanup Act (HSCA) site since: 2004
Primary Contaminants of Concern: landfill gas, including methane
Work by DEP and its contractors has demonstrated that landfill gas (LFG), including methane, exists within the site and potentially beyond the boundaries of the site, at levels that exceed standards established in Pennsylvania's Title 25, Chapter 273 regulations for combustible gas monitoring, off-site migration and mitigation at permitted municipal waste landfill sites. DEP has begun a prompt interim response at the site in order to help prevent the potential for offsite LFG migration.
Information Sheet (PDF)
In spring 2021, DEP’s contractor completed work to help control the off-site migration of landfill gas which consisted of installing a collection trench system to capture and vent the gas. In October 2021, DEP’s contractor submitted a remedial construction completion report.
Prompt Interim Response under HSCA
DEP has considered the following six alternatives to address the potential for LFG migration from the site: 1) take no action; 2) installation of an enhanced gas venting system; 3) Installation of a passive trench venting system; 4) installation of a semi-active trench venting system; 5) Installation of an active trench system; and 6) installation of impermeable barriers.
DEP chose alternative number 3, the installation of a passive trench venting system, because it complies with the applicable or relevant and appropriate requirements and is the most cost-effective.
The administrative record which contains the information that forms the basis and documents the selection of this response action is available for public review and comment. The administrative record is linked below in digital form.
Administrative Record Docket (PDF)
DEP published notice of its prompt interim response under HSCA at the Mazzaro – McKees Rocks Landfill site in the February 20, 2021 edition of the
Pennsylvania Bulletin. This included information on DEP’s hearing and public comment period.
Notice of Prompt Interim Response (begins on page 956)
An identical notice was published in the legal notices section of the Pittsburgh Post-Gazette on February 18, 2021.
On March 5, 2021, DEP issued a press release announcing the public hearing.
Public Comment Period on Administrative Record:
The administrative record will be open for comment from February 15, 2021 until May 21, 2021. Persons may submit written comments into the record during this time only, by emailing the Department at
DEP held a virtual public hearing to receive oral comments for inclusion in the administrative record on Tuesday, April 6, 2021.
Hearing PowerPoint Presentation (PDF)
More Information on the Hazardous Sites Cleanup Act (HSCA) Program
Hazardous Sites Cleanup Program page