A bulldozer moves trash at the Jefferson Parish Sanitary Landfill in Waggaman, La. Wednesday, July 25, 2018. The landfill on the West Bank of the Mississippi River has come under scrutiny because of horrible smells that have troubled residents on the East Bank and West Bank of the river in Jefferson Parish.

A private investigator reportedly questioning residents in Harahan about odors that may be emanating from the Jefferson Parish landfill is not working for the parish, President Mike Yenni said Tuesday.

In posts to two Harahan-related Facebook groups, a woman named RoseAnne Schaeffer wrote that an investigator knocked on her door Monday. 

"He introduced himself quickly by saying he is a private investigator and he is working for the Jefferson Parish landfill," Schaeffer wrote. 

Schaeffer posted a picture of a business card from John Carroll Investigations.

Her posts said the gumshoe asked her whether she was a homeowner and how long she had been in Harahan. He then asked several questions about the odors that residents have been complaining about for months, and that are often attributed to the parish-owned landfill across the river. 

Reached Tuesday afternoon, Carroll acknowledged knocking on residents' doors but denied he told anyone he was working for the parish landfill. He refused to comment further on who had hired him or what his objective was.

Yenni said there is no parish employee or contractor working as an investigator. Parish Councilman Paul Johnston, who represents Harahan and River Ridge, likewise said he wasn't aware of anyone being hired by the parish.

Yenni said it's possible the company the parish pays to run the landfill, Waste Connections, has hired someone to investigate. Waste Connections could not be reached for comment.

The odors emanating from the landfill are the subject of at least three lawsuits.

Seth Schaumburg, a lawyer who has filed one of them, urged residents in a Facebook post of his own to refuse to speak to anyone who presents himself as a representative of the landfill.

Neither Schaeffer nor Schaumburg responded to requests for comment. 

Schaeffer's post drew dozens of comments. A few commenters also reported having seen Carroll, but none said they had talked to him. Several were suspicious that he had been hired to discredit their claims in order to undermine their legal efforts.

Residents in the Harahan and River Ridge area this spring began posting to a Facebook group dedicated to cataloguing the rank odors that had been invading their neighborhoods and homes since late 2017. Residents in Waggaman also have registered complaints, and odors have been noticed in Kenner and Metairie as well.

The state Department of Environmental Quality has traced elevated levels of methane and hydrogen sulfide to the area where the Jefferson Parish landfill and two River Birch-owned landfills operate in and around Waggaman. The parish admitted that the gas and liquid collection systems at the parish-owned landfill had fallen into disrepair and that gases were escaping. It has begun work repairing the system and said it should be fixed within six months.

Parish officials have said that while they think the landfill is the source of some of the odors plaguing nearby communities, the administration and council are also eyeing nearby chemical plants, loading operations and midstream barge activity along the Mississippi River as possible culprits.

Follow Chad Calder on Twitter, @Chad_Calder and Faimon A. Roberts III, @faimon.