Six Mile Run AMD Treatment & Waste Coal Reclamation Project
Broad Top Township, Bedford County, Pennsylvania
Pennsylvania Abandoned Mine Reclamation Conference
State College, PA
June 26 – 27, 2014
Bradley R. Shultz, E.I.T., Skelly and Loy, Inc., 449 Eisenhower Blvd, Suite 300, Harrisburg, PA 17111, (717)232-0593, [email protected]
Terry Schmidt, P.E., Skelly and Loy, Inc., 449 Eisenhower Blvd, Suite 300, Harrisburg, PA 17111, (717)232-0593, [email protected]
AMD Pollution in Broad Top Township Located in northeastern Bedford County
Municipality with population less than 2,000
Over 80 identified AMD discharges
Three primary 303(d)-listed watersheds (28 square miles): Longs Run
Six Mile Run
Sandy Run
Historic underground (approx. 184 mine entries) and surface coal mining legacy of isolated Broad Top coal field since the 1800’s
Abandoned underground mines filled with water and drainage from partially reclaimed surface mines have created AMD throughout the Township
Broad Top Township/Coaldale Borough Watershed Advisory Committee (a.k.a. Six Mile Run Area Watershed Committee)
2001 AMD Assessment & Remediation Plan
Six Mile Run, Broad Top Township, Bedford County
Six Mile Run (SX0-D8) AMD Remediation Project
Annually 0.9 tons of iron, 0.8 tons of aluminum, and 8.5 tons of acidity estimated from AMD source
Conducted feasibility study of treatment options in 2008-2009 Reviewed mine maps in area
Collected additional flow and water quality data (weekly)
Peak flow rates much lower (never exceeded 72 gpm)
Determined available treatment area for passive treatment
Flows: Range from 18 gpm to 150 gpm, average ~50 gpm
Chemistry: Net Acidic, Moderate Fe & Al, low Mn
Site needed downstream due to location of borehole Six Mile Run Volunteer Fire Co. property – 1,800 feet downstream
Existing Township right-of-way along stream for sewer line
Stream crossing(s) needed for pipeline
SX0-D8 AMD Discharge Location
SX0-D8 AMD Discharge Location
Source to Treatment Area PlanSix Mile Run
SX0-D8 Existing Overall Site Plan
Exploratory Excavation of Borehole
Township personnel conducted exploratory excavation efforts of the borehole believed to be the AMD source
Borehole was clogged and most of water was upwelling adjacent to the borehole
Installed a vertical pipe into the upwelling to test ability to increase elevation of the source
Raised source elevation several feet to provide reasonable elevation drop to system
Cleaned up area at source eliminating a safety hazard in residential area
Elevated, contained and routed AMD to area where passive treatment possible
Exploratory Excavation of Borehole & Pipe Installation
Pipe Installed @ AMD Source
4-5’ Increase
Engineering Design Challenges
Limited elevation drop from source to treatment site, significant distance (~1,800 feet)
Right-of-way for sewer line not entire distance, multiple stream crossings?
Sewer lines – Pipeline, treatment area, and building expansion
Buildings and other items in residential yards
Considerable waste coal material at proposed treatment site (site previously housed a tipple coal processing facility)
Six Mile Run Volunteer Fire Co. – Expansion of existing facility and potential use of AMD for geothermal heating/cooling system
Use of VFW in residential area (odors???)
Potential to tie 2nd AMD source into pipeline (SX0-D7)
Too much iron for flushable limestone bed (8.5 mg/L)???
SX0-D7 AMD Source
SX0-D7 enters Six Mile Run near the SX0-D8 AMD source; flow & quality: acidity = 159 mg/L, flow = 20 gpm, Fe = 2.5 mg/L, Al = 17.7 mg/L, & pH = 3.4
Waste Coal Removal: Treatment System & Fire Company Facility Expansion
After lab analysis of the waste coal material, Six Mile Run Area Volunteer Fire Co. reached agreement with Robindale Energy Services for hauling to Seward Power Plant Low sulfur (0.7%) and moderate BTU (~6,000)
Incidental coal removal agreement thru Cambria DMO
Rough-grading of treatment system ponds
Greater than 21,000 tons of waste coal material removed from the site over 4 month period
Cleaned up coal refuse and barren area in Coaldale Borough/Broad Top Township to improve water quality and improve the community
Created level area for constructing fire company building expansion (average of 6’ of refuse removed from site)
Interim Site Plan: Waste Coal Removal-Treatment System Area
SX0-D8 Future Treatment Location (Approx. 1/3 miles from AMD Source)
Significant coal refuse removed and hauled to Waste Coal Power Plant
Rough grading of future treatment ponds
Seed & Mulched Area of Waste Coal Removal (Between System & Building Expansion)
Treatment System Design Evaluation report determined passive treatment applicable based on
available area and flow and water quality data
PA DEP Section 319 Grant funding
Pre-treatment settling pond, VFW, settling pond, and polishing wetland VFW aerial acidity loading rate = 20 g/m2/day
2,500 tons of limestone, 1.5 ft of compost
Coordination with Building Expansion Architect
SX0-D7 and SX0-D8 combined flow and water quality
Easily accessed site – O&M activities
Pipe clean-outs – Over 2,000 feet of proposed piping
Last Minute Change – FLB instead of VFW Odors from VFW outfall
O&M – Iron removal and compost stirring
Additional limestone & automatic flushing structure
SX0-D8 System Design Plan
SX0-D8 Project Permitting
NPDES – Discharge of Stormwater Associated with Construction Activities (PAG-02)
Erosion & Sediment Control Plan (County Application)
Chapter 105 – Stream crossings (pipeline installation beneath stream bed) and work within the floodway/floodplain Restoration waiver – Section 105.12(a)(16) of Chap. 105
Incidental Coal Removal – Cambria DMO
HEC-RAS modeling needed or is FEMA floodplain mapping available (see FEMA flood insurance map)
How long does it take for permit approval? SX0-D8 – Approximately 5 months (Chapter 105)
ROWs, utilities, etc.
Permitting Process – Chapter 105 EA Restoration Waiver
Permitting Process – Chapter 105 EA Restoration Waiver
Treatment System Construction
Treatment System & Pipeline Construction
SX0-D8 AMD Source: Before & After
Which backyard do you prefer?
Final SX0-D8 AMD Treatment System & Reclaimed Site Aerial View
New Building Addition to Fire Co.
SX0-D8 FLB Passive Treatment System
SX0-D8 FLB Based Passive Treatment System
3,000 ton FLB
Pre-Treatment Settling Pond
SX0-D8 Settling Pond & Polishing Wetland (2012)
SX0-D8: Polishing Wetland & Fire Co. Building Addition (2014)
SX0-D8 Treatment System: 2012-2014
Average Raw AMD:Flow = 47 gpmpH = 3.6Cond = 933 µS/cm
Average Final Outfall:Flow = 52 gpmpH = 6.4Cond = 820 µS/cm
Six Mile Run – Passive AMD Treatment Township is still working with residents to capture, collect, and
incorporate the 2nd AMD source (SX0-D7) into pipeline/system
With more than 10 passive treatment systems upstream, completion of SX0-D8 provides significant restoration downstream
Instream water quality just below SX0-D8 proves the efforts to date have worked (TMDL Monitoring Point 68): March 2006: pH = 5.4, Alkalinity = <10 mg/L, Hot Acidity = 10 mg/L
April 2012: pH = 7.4, Alkalinity = 15 mg/L, Acidity = 1.6 mg/L
Next two downstream AMD passive systems recently constructed (2014) and help to increase the restoration efforts towards the mouth No more restoration waivers for Chapter 105
Township is committed to maintain the successful operation/function of the systems (minimal O&M needed since 2012)
Six Mile Run Downstream
Questions???