SOUTH PORTLAND — City Assessor Jim Thomas has asked for sweeping documentation of Portland Pipe Line Corp. operations to support its request for a property tax abatement, a move that will delay his decision until mid-June.

One of the largest taxpayers in South Portland, the pipeline company is seeking a 42 percent reduction in the $44.7 million assessed value of holdings stretching over 210 acres, from its oil tanker pier at Cushing Point on Casco Bay to a vacant 72-acre wooded parcel off Highland Avenue.

In its abatement application, the company blamed its reduced property values on shifting economic factors and the city’s Clear Skies ordinance, which the company is challenging in federal court. However, it provided no details to back up the request.

Passed by the City Council in 2014, the ordinance’s ban on crude oil exports has “significantly reduced the value” of the South Portland-to-Montreal pipeline, according to the abatement application. The company, a Canadian-owned subsidiary of ExxonMobil and Suncor Energy, also “suffers from severe economic obsolescence that has not been taken into account in the assessment,” the application says.

In a letter to its lawyers, Thomas asked the company “to state the basis for (its assertion) that the property ‘is substantially overvalued’ and provide copies of any information that supports this assertion.”

Thomas asked specifically for more than 50 types of documents from the last several years, including recent property appraisals, inventories and records of capital improvements; company budgets, financial forecasts and capital plans; and engineering, feasibility and market studies on the potential of shutting down, cleaning up, redeveloping or selling pipeline properties.

Thomas initially was expected to respond to the company’s abatement application by March 14, but its lawyers requested a two-month extension to fulfill the assessor’s request for additional information.

“Given the breadth of your request, Portland Pipe Line’s current staffing levels and the importance of this matter to all parties, (the company) will need an additional 60 days to respond,” wrote attorney Jonathan Block of Pierce Atwood. The company asked for an extension to provide the documentation by May 14 and would give Thomas until June 13 to respond.

The 236-mile pipeline, which has carried foreign crude for 75 years, has largely shut down since refineries in Montreal started drawing oil from western Canada and North Dakota. The Clear Skies ordinance prevents the company from potentially reversing the pipeline’s flow to bring oil from Canada to tankers in South Portland.

If Thomas granted the abatement as requested, the city would lose $331,247 in property tax revenue, adding to the more than $1 million that taxpayers have spent so far defending the Clear Skies ordinance against the pipeline company’s lawsuit.

If Thomas refuses to change pipeline property values, the company could appeal his decision to the city’s Board of Assessment Review and proceed to court if the matter isn’t resolved at the municipal level.

Kelley Bouchard can be contacted at:

[email protected]