BISMARCK, N.D. _ More than 600 barrels of water spilled at an oil well site in Williams County, the state Health department reported Thursday.

The company operating the site, Houston-based Oasis Petroleum North America LLC, reported that its initial data showed 690 barrels of freshwater spilled and some flowed into a nearby ditch. As of Thursday afternoon, all but 40 barrels had been recovered, the company said.

A health department inspector was sent to the site, about eight miles north of Williston, to test the water and make sure it had no chemicals in it. Oasis  reported the water had not been treated at the time it spilled.

Kris Roberts, an official with the department’s Environmental Health Section, said it likely would take a couple of weeks to get results from tests of the water.

“Almost all of the water froze almost immediately,” Roberts said.

He said most of the 40 barrels that had not been recovered was in the ditch. The fact that the water froze as quickly as it did is a good sign it did not have any high concentration of chemicals, he said.

The spill comes a day after two others were reported to the department, one each from Williams and McKenzie counties. The larger spill consisted of 300 barrels of crude oil at a well site eight miles east of Williston.

Denver-based Zavanna LLC, the operator of the site, reported that as of Wednesday afternoon, 295 barrels had been recovered inside a storage tank containment dike. Some of the oil had sprayed onto agricultural land next to the site.

A smaller spill, of approximately 35 barrels of oil, was reported Wednesday at a site about 20 miles northeast of Watford City in McKenzie County. The well site is operated by Houston-based Newfield Production Co. As of Wednesday afternoon, 20 barrels of oil had been recovered. Some of the oil had sprayed onto the snow and a small frozen pond near the site.

Health department officials were sent to both spill sites on Wednesday. Roberts said the cleanup was ongoing.

Wednesday’s spill near Williston was the third spill of more than 100 barrels of oil this month, according to a new database on the Health Department website.

Two previous spills were reported as having been contained — one on Feb. 2 in McKenzie County totaling 100 barrels and one on Feb. 7 in Divide County totaling 180 barrels.

One other spill, contained on-site on Feb. 2, consisted of oil-based drilling mud. It happened at a separate McKenzie County site.

In all of January, the department reported 10 spills of 100 or more barrels of saltwater, two oil spills of more than 100 barrels and one spill of other substances such as drilling mud.

Roberts said spills tend to be cyclical.

“In this kind of weather, you’ve got two things that happen: mechanical failures due to the weather and human error,” he said.

Roberts said he anticipates more incidents when the ground begins to freeze in winter and when it thaws in the spring. The increasing number of operating wells in the state also must be considered, he said.

“When you have more wells, you’re going to see more spills. We are gradually increasing the numbers (of spills) we’re seeing monthly and annually,” Roberts said.

The department of health’s oil field environmental spill website can be found at

Reach Nick Smith at 250-8255 or 223-8482 or at