Oklahoma had the second-highest number of hazardous liquid spills from pipelines and the third-highest amount spilled in the nation since 2010, according to data from the U.S. Pipeline and Hazardous Materials Safety Administration.

Over the past seven and a half years, pipelines in Oklahoma have spilled or leaked more than 1 million gallons, or 25,220 barrels, of crude oil and more than 19,000 barrels of other hazardous liquids, according to the PHMSA data.

In total, there have been more than 248 spills or leaks in the state from pipelines used to transport hazardous liquids – second only to Texas, which had 1,066 spills during that time period. The data shows 170 of the 248 spills in Oklahoma since 2010 were crude oil spills.

Hazardous liquids pipeline systems carry crude oil, refined petroleum products such as gasoline, highly volatile liquids such as propane or butane, liquid carbon dioxide, anhydrous ammonia and other liquids, according to the PHMSA.

During the period between 2010 and 2016, Oklahoma had an average of 12,163 miles of hazardous liquid pipeline, which ranked third in the nation behind Texas and Louisiana, according to the PHMSA.

Earlier this week, The Frontier reported that 1.2 million gallons of oil and more than 9 million gallons wastewater had been spilled in the state by oil and gas companies at well sites and storage facilities, but not including pipeline spills. The Oklahoma Corporation Commission, which provided the previous spill data, does not oversee interstate pipelines.

Both on the national and state level, pipeline promotion and protest have captured the attention of the public and legislators.

Protests against the installation of the Dakota Access Pipeline at the Standing Rock Sioux Indian Reservation in North Dakota garnered national attention last year and this year, while a fight between Republicans in Congress and former President Barack Obama over the Keystone XL pipeline played out over the course of years.

A bill by Oklahoma Congressman Markwayne Mullin that would remove the President from the approval process for pipeline construction across the Mexican and Canadian borders recently passed the U.S. House of Representatives and is now before the U.S. Senate.

View an interactive map of where pipeline spills in Oklahoma have occurred since 2010.

As of June 30, there have been 17 spills from pipelines in Oklahoma, according to the PHMSA.

The largest pipeline crude oil spill this year occurred on April 21 near Loyal in Kingfisher County.

Though early estimates placed the spill at around 18,900 gallons of crude oil, later estimates put the amount closer to 35,000 gallons, or 827 barrels, according to reports obtained through PHMSA. About 600 barrels were recovered in the cleanup effort.

According to reports to PHMSA by the company that owned the pipeline, Houston-based Plains Pipeline, L.P., an 8-inch transfer line pipe buried about 4 feet underground developed a pinhole leak, causing the oil to leak out into farmland. Rain then carried the oil into a nearby creek.

The carbon steel pipe, which was manufactured and installed in 1960, is believed to have developed the leak because of internal corrosion, though the cause is still under investigation, according to Plains Pipeline’s report to the PHMSA.

In total, damage and costs associated with the spill are estimated to be around $875,000, according to the PHMSA.

But April’s pipeline spill was not the most expensive over the past seven years.

On May 13, 2013, a pipeline owned by Houston-based Enbridge Pipelines LLC near one of the company’s terminals in Cushing leaked approximately 2,200 barrels of crude oil, according to the PHMSA data. Though the leak occurred outside the terminal’s containment unit, the oil traveled to a small containment pond near one of the company’s tanks.

However, the oil continued to flow, escaping the small containment pond and entering a nearby tributary that flows into Wildhorse Creek. Eventually, the oil flowed into a large containment pond. According to Enbridge’s 2013 Corporate Social Responsibility report, several animal fatalities occurred as a result of the spill. The cleanup effort was complete June 7, 2013 and remediation was completed June 21, the report states. All but 175 barrels of oil were recovered, the PHMSA data shows.

The estimated cost for environmental remediation alone was around $7.8 million, according to reports from Enbridge to PHMSA. The total cost of the spill was estimated to be around $14.5 million, according to the PHMSA.

“Cushing is kind of a game changer for oil and gas in Oklahoma in that we became a hub, a collection point, for all kinds of oil and gas and tar sands,” said Barbara VanHanken, chair of the Sierra Club’s Green Country chapter, which represents Tulsa, northeastern and southeastern Oklahoma. “It’s kind of a critical environment in Cushing, Okla.”

The Sierra Club is the largest environmental organization in the nation, with 64 local chapters nationwide.

Over the last seven years, the company with the most pipeline spill incidents was Houston-based Enterprise Crude Pipeline LLC. The company had 37 separate leak incidents between 2010 and June 30, 2017, resulting in more than 487,000 gallons, or 11,604 barrels, of crude oil being spilled.

Phone messages left for Enterprise’s spokesman by The Frontier were not returned.

Chad Warmington, president of the Oklahoma Oil & Gas Association, said pipelines are the safest and most environmentally friendly way to move oil and natural gas over long distances.

“The track record is pretty tremendous,” Warmington said. “It’s much safer than moving it by truck, it’s much safer than moving it by train. One of the things beneficial for Oklahoma, is that we’ve got great pipeline infrastructure. We ought to be encouraging people to put more pipes in the ground to keep that track record of safety up.”

Technology, Warmington said, along with more uniform and newer operating procedures have helped make spills from pipelines rare, which is good for both the environment and companies’ bottom lines.

“It’s a fundamental product issue — the more of that product reaches its destination, the better you are in terms of profitability,” Warmington said. “With monitoring and the ability of companies to quickly shut down leaks, you don’t have large spills. If you don’t have large spills, it makes cleanup a lot easier.”

However, not all are convinced that pipelines are safe enough.

“There’s a push to construct more pipelines, but that doesn’t take care of the pipelines that were constructed 50 to 60 years ago that are breaking apart,” VanHanken said.

VanHanken said she is concerned about a focus on profits over the long-term sustainability of the environment, which may make it easier for some to look the other way when hazardous liquid spills do occur.

“Despoiling the land and our water and our air, that’s very serious to me,” VanHanken said. “That’s what my grandchildren and their grandchildren want to have available to them as well as I did. I as a human being think it is totally irresponsible for me and my generation to turn our backs on what has been happening. It’s our responsibility to make a change and hold people accountable.”

Go here to view the entire PHMSA data set showing pipeline spills in Oklahoma between 2010 and June 30, 2017.