By Melanie Stegner

news@pctribune.com

Hancock Concrete submitted a proposal to the county requesting to expand their current gravel pit located north of Highway 28, east of the City of Glenwood. The expansion area will include approximately 40 acres adjacent to the existing gravel pit. After the approval of the Interim Use Permit back in October, an Environmental Assessment Worksheet was required to be completed. Now the county must decide if there is a significant need for an Environmental Impact Study to be completed. 

The existing pit is an active gravel mining operation. The facility extracts, stores and distributes crushed stone for use in concrete operations at other facilities. Operation activities include aggregate extraction, washing and staging of gravel, crushing and recycling of concrete and a series of ponds. As the proposal states, nothing will change in the company’s activities at the site. 

The pit has been in operation since the 1980s and was purchased by Hancock Concrete in 1991. Extraction and processing operations currently conducted at the gravel pit consist of the removal of earthen material for aggregate mining. Extracted material is utilized by roadway construction industries. The process includes the use of crushers, screens, conveyors, mobile equipment for production and other construction-related operations. Water for processing is provided through a well within the existing gravel pit. Internal roads along the perimeter of the gravel pit change periodically as mining activities advance. Berms, fences, gates and landscaping are implemented to provide safety buffers.

The proposed expansion adds approximately 40-acres north of the current location and the proposed mining depth is 25 feet. The property currently has roads and equipment sufficient for the operation to sustainably operate at the expanded size. No new buildings, equipment or remodeling are required. 

The project includes the land reclamation process when mining activities are complete including the removal of equipment, buildings and all other materials not part of a natural environment. Stormwater and wastewater ponds will be drained, capped and hydroseeded or left as cattle ponds. The site would be graded and revegetated to look like a natural part of the environment. The expansion area includes 40 acres of cropland currently.

Hancock Concrete has secured permissions from the DNR and has submitted the mining application to Pope County. They plan to maintain a 1,000-foot buffer from neighboring land. 

Pope County is comprised of a complex network of surficial and buried sand and gravel aquifers, with local deposits of over 80 feet. The mapped surficial and buried aquifers in the project area consists of the Belgrade-Glenwood sand plain, Otter Tail Aquifer, Crow Wing Aquifer, and the Browerville Aquifer. The thickness of buried sand and gravel deposits in Pope County generally ranges from 20 to 40 feet. The thickness of surficial sand and gravel in the project area ranges from approximately 60 to 100 feet.

The aquifers in this area are rated as having a very high sensitivity to pollution, meaning the ease with which a surface contaminant moving with water might travel to and enter a subsurface water source. The estimated vertical travel time for waterborne surface contaminants to enter surficial aquifers in a very high sensitivity area is hours to months. The portion of the Browerville Buried aquifer below the project area has a very low sensitivity to pollution with an estimated vertical travel time for water-borne surface contaminants of a century or more.

Based on research from the Minnesota Department of Health, the domestic water wells located near the project area have a static depth of 50-60 feet. The area is within a Wellhead Protection Area as well as a Drinking Water Supply Management Area. Glenwood’s WHPA is 533 acres and encompasses the majority of the project area and the Glenwood DWSMA is 1,003 acres and encompasses the entire project area. The Pine Hill Mobile Home Park is one mile south and has WHPA and DWSMA south of the project area. The well log data shows a clay layer exists between approximately 50-140 feet from the surface, separating the shallow aquifer from the buried aquifer. The project proposes a maximum mining depth of 25 feet, keeping the activities approximately 25-35 feet from the groundwater, having no direct impact.

The existing operation has a maintenance facility for wastewater discharge near the southern portion of the pit. It generates minimal wastewater and no changes to this facility are part of the proposal. The current stormwater runoff flows overland. The existing operation has a discharge plan regulated by the Minnesota Pollution Control Agency and with no requested changes, a new one is not necessary. 

Hancock Concrete has two irrigation wells in the current operation, one is active and will continue to be used and the other is inactive and sealed. Since 2018, the gravel pits water usage has gone done by roughly 25 percent.

According to the MPCA there are no known leaks or spills that have occurred at the existing pit. Six leaks, all near the current railroad, have occurred at nearby MPCA sites within one-half mile of the project area. The addition of the proposed area is not anticipated to exacerbate any pre-existing environmental hazards, it was stated.

Solid waste storage is maintained with the use of a covered trash dumpster and a metal dumpster. Scrap concrete is staged and crushed at the south side of the existing pit and is then delivered to the gravel pit to be recycled.

As the project area consists of mainly agricultural land as well as the surrounding area, there is limited use for wildlife habitats. According to the EAW, the DNR determined that there are no significant endangered plant or animal species in the project area.

Hancock Concrete has been working with the county on this proposal since October of 2021 by requesting an IUP. That proposal triggered the necessity of the EAW according to state statutes. The county is the responsible government unit for the required documents. 

Several public comments and concerns were raised during the public notice period including from Daniel Disrud of the Minnesota Department of Health stating concern over groundwater impact and the state of the buried aquifer. Groundwater testing was done in the project area and showed the existence of tritium as well as an elevated chloride/bromide ratio. MDH determined that the clay layer of the aquifer, although it exists, is leaky. The proposed area and mining activities could possibly make the existing layer more vulnerable to contamination.

Of the two wells near the site, one has tested high for nitrates. “We’re not sure why one is elevated and the other isn’t,” said Mike Howe on behalf of the City of Glenwood. “The city has a history of losing water due to nitrate contamination. The water also contains tritium, which is used to determine the age of water. Glenwood’s water is young and the chloride/bromide tests support that. We don’t know if washing gravel causes the growth of nitrates.”

Mike Howe, Water Resource Planner working on behalf of the City of Glenwood, expressed concerns over the location of the project within the Wellhead Protection Area and the standards for the Groundwater Management Area. In response, Hancock Concrete referred to the standards and measures within their EAW and the standards of the current operation that exists in the same area. 

Commissioner Gerde asked if the city has been prevented from testing prior to this proposal and if the concern had arisen, why didn’t testing take place years ago. “Why is it a concern now when the issue has been ongoing for a while? If we go along with the recommendation to consider the EIS unnecessary, we aren’t holding the city back from doing any testing. If we request to have the EIS completed, we need to show that there is a significant need.”

“Yes, we would need to provide the proposer with the specific lacking information we are looking for within five days of the request,” said County Attorney Neil Nelson. 

Karen Kromar, Planner Principal of the Environmental Review Unit of the MPCA provided a statement that the MPCA has reviewed the EAW and has no comments at the time of publication. The same is true of the State Historical Society. 

In a letter from Troy Nelson, Attorney for the City of Glenwood, the city is concerned that the 25-foot limitation may not be enough to protect the city’s drinking water supply. In response, the Senior Environmental Planner from Stantec had their hydrogeological team review the city’s concerns with the project as proposed. “Given that potentially hazardous materials, specifically petroleum, are controlled and stored appropriately outside of the wellhead protections area and that a Spill Prevention, Control and Countermeasure Plan is in place, it is our opinion that no further investigation is necessary,” that review stated.

The board voted to approve resolution 202238 and the record of decision along with the findings of fact that support a negative declaration for the need of the EIS for the expansion, 4-1, with Commissioner Wagner giving the sole opposing vote. In the interim, Hancock Concrete and the City of Glenwood plan to be in discussion regarding the concerns going forward. From the county standpoint, Hancock Concrete has met all requirements of the permit and there are no significant reasons to require the EIS.