Deer Creek II Reclamation Project

Cherokee County, Kansas


Introduction

Rising above the quiet surroundings of West Mineral Kansas like the majestic giant that he is, Big Brutus is a reminder of a past that once kept Cherokee County Kansas economically fit.

Approximately 23% of the State of Kansas is underlain by valuable coal resources. Nestled in the far southeast corner of the state, much of Cherokee County has been heavily mined for coal by both surface and underground mining methods. From the time of that first mining until July 1969, almost 14,000 acres in Cherokee County had been mined with little to no reclamation required by any law. The resulting problems included dangerous highwalls, dangerous piles and embankments, hazardous water bodies, vertical openings, and an extensive amount of surface subsidence under towns and roads. Kansas currently has approximately 347 abandoned mine sites identified as health, and safety problems statewide. The current projected cost to reclaim these sites is in excess of $800 million dollars. This figure does not include the additional costs for grouting beneath the cities of Pittsburg, Scammon, or Weir to help stabilize the ground surface.

In Section 28, Township 32 South, Range 22 East of Cherokee County, the Deer Creek II Reclamation Project represents a typical AML site where coal mining coal was accomplished without any thought given to the long-term impacts to the surrounding community. At this site, the land was mined for Mineral, Fleming and Croweburg coal. Deer Creek II is owned by the State of Kansas and is being utilized and maintained by the Kansas Department of Wildlife, Parks and Tourism (KDWPT) as part of the public use areas known collectively as the Mined Land Wildlife Areas (MLWA). This project is located in MLWA Unit 35. Prior to reclamation, the traveling public was exposed to safety hazards along NW 90th Street, Lawton Road and NW 100th Street due to the presence of over 6,000 linear feet of Priority 2 dangerous highwalls in very close proximity to the roads (Photo 1). Due to erosion, this highwall was beginning to encroach into Lawton Road reaching almost to the roadway in numerous places. For years, Deer Creek II ranked #1 on the Kansas AML inventory.

A 2013 Google Earth Photo showing a rectangular tract with a long water body along the west, south, and east perimeter and several smaller shallow water bodies in the central portion.

Photo 1: The Deer Creek II Project in 2013 before reclamation activities.

Highwall Remediation

The goal of every Surface Mining Unit AML reclamation project is to address safety hazards while minimizing impacts to existing vegetation, wildlife and aquatic habitats in a cost-effective manner. Over 1.6 million cubic yards of earth was moved to accomplish this goal. Existing on-site spoils provided the necessary fill materials. Before and during grading operations, devices were installed to control erosion and minimize sediment transport thus meeting storm water pollution prevention plan requirements. Permanent devices were installed post reclamation.

The partial filling of the strip pit impoundment, if not accompanied by other design changes, would have impacted the hydraulics of Deer Creek at Lawton Road by reducing the amount of water the land could store. To replace the lost water storage, it was necessary to provide for unhindered water transfer between Deer Creek and newly constructed wetlands and open water impoundments.

To accomplish this, Mikon (the design engineering company) designed a major hydraulic structure, a two-way concrete weir almost 60 feet long (Photo 2) to replace a blown-out culvert through the berm between the existing strip and Deer Creek (Photo 3). Even with changes to the configuration of the culvert under Lawton Road, from 6' diameter CMP to 6' equivalent elliptical culvert with a roadbed raised one foot (Photo 4), the hydraulic capacity at Lawton Road was only nominally changed. The post-reclamation available storage is restored between rain events by allowing the newly created open water impoundment to drain back down, via four 2-foot diameter openings in the concrete weir. The weir elevation was set to take advantage of all water storage possible in the post reclamation final impoundment prior to Deer Creek flooding and overtopping Lawton Road. The original 20 acres of open water that replaced by 5 acres of open water, a 10 acre wetland, and a 5 acre wetland. Both wetlands had water level control spillways installed that would allow the water to be raised or lowered in the wetland as needed.

A concrete weir between the on-ste wetland and Deer Creek; the weir has four openings to allow high water to pass between the two water bodies.

Photo 2: The newly constructed concrete weir.

An eroded short earthen dam, covered in driftwood. There is a gap in the dam next to a half-sunken steel pipe.

Photo 3: The blown-out culvert and earth structure replaced by the weir.

Waer passing into an elliptical culvert under a gravel road.

Photo 4: The reconstructed culvert under Lawton Road.

Construction

Because of the large volume of material to be moved, the contractor brought in a fleet of leased machinery, much of which was equipped with GPS guidance systems. This is not often seen on small Kansas reclamation projects. Clearing and grubbing was done in compliance with the Migratory Bird Treaty Act. Brush piles were left strategically around the site for habitat enhancement. The project design included the use of boulder barricades to outline parking areas. The geology of the site was such that stone excavated during the backfilling and grading was of sufficient quantity to more than supply the 1,178 linear feet of boulder barricade. During the handling of the rock for the boulder barricades, extra boulders were used to create a unique habitat, a rock wall. This idea was well received and implemented into the project at no additional cost.

The Surface Mining Unit has successfully used the concept of a rock toe when filling into water filled pits on many projects. The rock toe on this project used over 12,000 tons of limestone. Because the rock toe can be placed at an angle of repose of about 1:1, less water storage area is lost than if spoil material with its angle of repose of about 6:1. The rock also creates a niche for small fry to hide in the water.

A series of earthen cofferdams within the section of existing strip pit being filled allowed the contractor to prevent mud from moving into that portion of the existing strip pit not being filled. This was important to save the existing fishery. The majority of all the earthwork was completed by late 2014. Parking areas and boat ramps were constructed to enhance the site for public use. To prevent off-road four-wheeling, the area was fenced; but with crawl-through friendly smooth wire instead of barbed wire.

The 142 disturbed acres in the project area were reseeded with warm season native grasses and forbs as well as Butterfly Milkweed, Common Milkweed, and Swamp/Rose Milkweed to encourage the re-establishment of the Monarch Butterfly habitat in Kansas. For some of the larger mammals within the area, the KDWPT MLWA Manager and Assistant Manager provided radish and turnip seeds that were planted during the second growing season.

An aerial photograph showing the changes to the area; a rock wall, a 10-acre wetland, a 5-acre wetland, new boat ramp, a new weir and 5 acres of open water were installed along the western and southern portions of the site.

Photo 5: The project area after construction was completed.

Results and Effectiveness

Most of the 14,500 acres originally mined pre-law that make up the MLWA Units were left to vegetate naturally. The result is that most acreage is tree covered. The expanse of warm season native grass on the Deer Creek II project area adds some much needed habitat diversity. With the Assistant Manager of the MLWA stationed in an office less than two miles away, management of the two wetlands using the installed water level control structures can be done on a regular basis to allow for a moist soil response. Residents have commented on how the number and variety of waterfowl have increased since the project was completed.

The main benefit of the Deer Creek II AML project was that the traveling public is no longer exposed to the 6,000 linear feet of dangerous highwall along the county roadways. The incidental benefits were the improvement of publicly used lands for recreation and habitat improvement for wildlife. The area will be enjoyed by generations to come.