The Ohio Department of Natural Resources (ODNR) said Friday a dozen small earthquakes in northeastern Ohio over the last year may have been triggered by a wastewater disposal well in Youngstown, and it unveiled a series of tough new regulations for injection wells.

In a 24-page preliminary report, the ODNR said "a number of coincidental circumstances appear to make a compelling argument" that Northstar 1 -- a Class II deep injection well owned by Youngstown-based D&L Energy Inc. and operated by Northstar Disposal Services LLC -- caused 12 seismic events beginning in March 2011. The well began operations on Dec. 22, 2010.

"To establish a better understanding of what may have happened, further analysis and detailed modeling of all factors must be completed on the Northstar 1 well and the surrounding geology," the ODNR said. "This work is already under way through ODNR and cooperating agencies and institutions."

State regulators said that although Ohio currently meets or exceeds all of the standards and regulations set by the U.S. Environmental Protection Agency (EPA) for Class II injection wells, the ODNR was enacting several safeguards to prevent further quakes, including a ban on drilling any new Class II injection wells into the Precambrian basement rock formation.

Operators will now be required to submit a complete suite of geophysical data -- including gamma ray, compensated density-neutron and resistivity logs -- for any newly drilled Class II injection wells. They must also install a continuous pressure monitoring system, an automatic shut-off system if fluid injection pressure exceeds a maximum limit set by the ODNR, and an electronic data recording system to track all fluids brought by a brine transporter for disposal.

"Ohioans demand smart environmental safeguards that protect our environment and promote public health," said ODNR Director James Zehringer. "These new standards accomplish this goal."

In a statement, D&L said the ODNR was basing its conclusions on limited scientific data from outside sources.

"Everything done at the Northstar 1 well site was done with ODNR knowledge and approval," the company said. "While ODNR repudiates drilling into the Precambrian formation now, the agency permitted D&L to do so in the case of the Northstar No. 1 well and then used this site to collect geological information. The current preliminary report does not indicate ODNR accepts any responsibility for its decision.

"It is unfortunate ODNR pre-empted a thorough search for information, opting instead for a politically expedient preliminary report that sacrifices true understanding for haste."

Although the ODNR also said wells currently penetrating Precambrian basement rock must be plugged with cement, it did not specifically order the Northstar 1 well to be closed. The agency asked D&L to halt operations at the well on Dec. 30 (see Shale Daily, Jan. 5; Jan. 4). The ODNR said 495,622 barrels of fluid had been injected into the well as of Dec. 31.

"No determinations have been made," D&L spokesman Vince Bevacqua told NGI's Shale Daily. D&L said shortly after the injection well's shutdown that it would pay for a study to determine the cause of the seismic activity (see Shale Daily, Jan. 11). On Friday D&L said that research could cost $1 million.

"Today's report comes as a surprise as D&L and ODNR have a meeting scheduled in Columbus later this month to discuss the D&L study proposal," the company said. "D&L calls on ODNR to let science guide its regulatory actions and to remain open to the data they requested in the first place."

Inspectors from the ODNR's Division of Oil and Gas Resources Management visited the Northstar 1 well 35 times, from April 26 through Dec. 15, 2011.

D&L is currently constructing three additional Class II injection wells in the region: Northstar United 2 in Trumbull County's Liberty Township, and Northstar Khalil 3 and Northstar Collins 6 in Mahoning County's Coitsville Township. The company has also applied for a permit to construct a saltwater injection well, the Northstar Nexlev 5, in Trumbull County's Hubbard Township.

The ODNR said it would also purchase four additional seismometers and was in the process of finding an independent seismic expert to look at the data collected so far and conduct its own analysis.

In its report, the ODNR acknowledged that "all the evidence indicates that properly located Class II injection wells will not cause earthquakes," and it added that geologists believe it would be "very difficult" for those wells to meet all of the conditions necessary to induce seismic activity, specifically:

The report said the closest known fault system is the Smith Township Fault, which runs in a northwest-southeast direction in Mahoning County. Maps of the fault indicate that it has had recurrent movement throughout geologic time.

According to the Ohio Seismic Network, 12 earthquakes with a magnitude greater than 2.0 have been recorded in the Youngstown area since March 17, 2011, when two quakes -- of 2.1 and 2.6 magnitudes -- were recorded. Additional earthquakes were recorded on Aug. 22 (2.2 magnitude), Aug. 25 (2.4), Sept. 2 (2.2), Sept. 26 (2.6), Sept. 30 (2.7), Oct. 20 (2.3), Nov. 25 (2.2), Dec. 24 (2.7), Dec. 31 (4.0) and Jan. 13, 2012 (2.1).

"We have a situation based upon a very rare geologic anomaly where it appears that a well intersected with a small, minor fault," Tom Stewart, executive vice president of the Ohio Oil and Gas Association, told NGI's Shale Daily. "That is uncommon, and we need to keep that in perspective as we go forth to try to change the regulatory structure. Having said that, when you look down the list [of ODNR's regulatory changes], I don't see a lot of problems with what they are suggesting.

"Probably their best suggestion is for a recorded, constant measurement of pressure and rate. Nobody is going to complain about that. I think a lot of operators already do that so they can prove they are staying within the allowable maximum operating pressure that's allocated to them by their permit."

Last year regulators in Arkansas established a moratorium on wastewater disposal wells in an area of the Fayetteville Shale after similar quake activity was reported there (see Shale Daily, July 29, 2011; March 4, 2011).