RFB-134-19 Andrews Run Phase 3
RFB-134-19 Andrews Run Phase 3
Estimate:
$502,045.00
Estimated Length of Project:
(Substantial Completion) + 300 Calendar Days (Final Completion)
The proposed Andrews Run Phase 3 AMD Abatement Project, approximately 36 acres total, consists of an 11 acre acid filled mining impoundments and 7 acres of barren refuse/acidic clays in the headwaters of Andrews Run, and correcting erosion problems at the outlet of the Andrews Run Phase 2 project area in Muhlenberg County. The sites are located in the Rochester Quadrangle. The northern access is at 37° 13′ 55″ N, 86° 57′ 35″ W, the western is at 37° 13′ 30″ N, 86° 58′ 35″ W. To reach the all the sites from the intersection of US 431 and KY 70 in Browder take KY 70 East. For the north (existing) entrance go ~6.5 miles to Riverside Road. Turn left onto Riverside Road go ~2.7 miles to the north entrance to the project site on left. For the west (newer) entrance go 2.9 miles and turn left onto Old Ennis Rd. Go 0.4 miles and turn left onto Riverside Church Rd and go 2.2 miles to the KY Fish and Wildlife gate on right
From the existing Riverside Road KY Fish and Wildlife gate construct 1,850’ of gravel entrance using geo-grid and filter fabric with the roadway stone. Two set of pipes are included for use if the ENGINEER deems their placement to be necessary. Continue to construct an earthen road back to the work area. Use onsite materials to cover the first barren area and bury the exposed refuse. Downstream of the main upper work area construct a silt trap before major earthwork disturbance. At the 0.9 acre impoundment, spread agriculture limestone over the impoundment and use onsite material to fill sufficiently to create positive drainage. Release the water through a limestone sand dosing station. At the 16 acre area, use onsite material to grade and cap the existing acidic clays, refuse, and mud. Spray agriculture limestone across the impounded water. Cut the “berm” to slowly release the water through a limestone sand dosing station. The final drained and capped surface will also set the final grade for the ditches. Use the adjacent materials and backfill the pit. Leave all disturbed ground no steeper than 3:1 slopes. Construct a 2-stage meandering channel with meanders on ~30’ radius centers. Install step pools 4’ deep approximately every 200-300’ in the channel. If the grade at any point is more than 10% then construct a type “A” silt traps and step the water down to the next level with a step-pool type ditch.
At the north end of the project use the onsite large rocks and imported cyclopean rip-rap to construct a rock check in the channel. The check must be keyed into the bottom and sides of the existing channel and use large rock locked in place with smaller class III cover rock. Remove the existing culvert from the road and grade side slopes to 2:1 slope.
The project site has previously been disturbed by coal mining operations. Construction disturbances will be kept to a minimum with a stringently formulated sediment and erosion control program. Prior to beginning any major earth disturbance (excluding initial site preparation for access only), all silt control measures will be installed including silt traps and silt barriers (bales & silt fence). Tree clearing must be completed before March 15th. All disturbed areas will be promptly revegetated at the end of construction. Use the AML wildlife seed mixture. Enough mulch has been included for two applications in the event the application of the cover crop is required.
Project Location: Muhlenberg