A proposed hydrogen energy plant west of Bakersfield got some bad news late Friday when two government agencies issued a detailed report raising multiple questions about the project.

The analysis found  “significant, and for the most part, unresolved issues” with Hydrogen Energy California’s controversial plan for a $4 billion power and fertilizer plant near Tupman.

It’s a preliminary report subject to further review.

The company declined to respond but people who would be neighbors of the plant, if it’s built, were quick to welcome the report.

The 2,154-page draft environmental review was issued by the California Energy Commission and the U.S. Department of Energy.

It points to 15 areas — from air quality and traffic to water supply and power plant reliability — that remain to be mitigated or discussed further. In some cases, the review said, the project also known as HECA does not, as currently proposed, comply with existing law.

Friday’s staff assessment does not constitute a decision by the commission or the department. The next steps are for commission staff to conduct a public workshop and begin a 45-day public comment period. Not until those are complete would the commission vote on the project’s fate, possibly by the end of this year.

With $408 million from the Department of Energy, Massachusetts-based owner SCS Energy LLC aims to use coal and petroleum coke to power what it says would be a 200-employee facility.

In what energy industry observers call a promising innovation, HECA proposes to sell the plant’s byproduct carbon dioxide to Los Angeles-based Occidental Petroleum Corp. for use in stimulating nearby oil wells. After that, the soda pop gas would be stored underground indefinitely in a process called carbon capture and sequestration, thereby reducing the project’s greenhouse gas emissions.

Project opponents have complained that the plant’s emissions would pollute their air and that plans for using anhydrous ammonia would endanger their safety. They also object on the basis that the plant’s truck traffic would damage their roads.

Project opponent Tom Frantz, a farmer in Shafter, called the review’s conclusions “good news.” “The (commission) is basically agreeing with people like me that this project has not presented everything it needs to to show that it is a valid, good project that we need to have,” he said.

The Sierra Club has joined local opponents by raising concerns that air pollution credits purchased by HECA to offset its emissions may be invalid.

HECA officials issued a statement Friday saying they were reviewing the assessment and that they would respond before the comment deadline.

“We look forward to participating in upcoming public workshops and working to resolve open issues,” the statement read.

The project would be located on 1,106 acres of private land 7 miles west of Bakersfield city limits. Most of that land would serve as a buffer area.

Using a process called integrated gasification combined cycle, HECA would turn its fuel into nitrogen-rich products, mainly fertilizers. Alternately, during times of peak demand for electricity, the plant would generate 300 megawatts of power for sale to the power grid.

HECA originally belonged to oil giant BP and international mining company Rio Tinto, which proposed to generate power but not manufacture fertilizers at the plant. But after determining their plan was economically unfeasible, they sold it in 2011 to power plant developer SCS, which has said it plans to sell the facility after completion.

The project took a step forward in February when the San Joaquin Valley Air Pollution Control District signed off on HECA’s expected air pollution emissions.

If approved, the project would provide an average of 1,160 jobs during its four years of construction work.