On December 19, the Department of Environmental Protection released the 2013-2018 Act 54 Assessment Report, the fifth in a series of reports required by Act 54 of 1994 documenting the impacts of underground coal mining on surface structures, water supplies, streams, land damage, groundwater and wetlands.
The report, done by the University of Pittsburgh, analyzed the impacts of 49 underground bituminous coal mine operations which undermined 28,854 acres in Greene and Washington counties during the reporting period of 2013-2018.
Stream Damage
Of the 86 miles of streams undermined deep coal mining, 59 miles or 40 percent experienced multiple impacts such as loss of flow or pooling and on average their Total Biological Score declined significantly.
In the last Act 54 report covering 2008-2013 in 2015, the University of Pittsburgh also found 40 percent of the streams undermined by deep coal mining suffered the same sorts of impacts. Click Here for more.
Of the 82 Stream Recovery Evaluation reports mining companies are required to do where there are impacts, mining operators were released from further responsibility for 42 of the streams. 40 of the SRE reports remain unresolved.
The report found, “An alarmingly high proportion of SRE reports did not contain the amount of monitoring data suggested by technical guidance.”
“Many more stream impacts have not yet had an SRE report submitted to the DEP, indicating that the majority of the 179 stream impacts during the 5th assessment period have yet to be resolved and released,” according to the report.
“Heaves and fractures in stream beds can occur following undermining. Fracture sites under those conditions have occurred at distances as long as 1,500-ft from the mining front.
“During the 5th assessment period [this report], 12 instances of fish kills resulting from flow loss on nine undermined streams were reported with an additional fish kill due to contaminated augmentation water.”
“Grouting was performed 60 times on 46 streams during the 5th assessment, for a total of 8.65 miles of grouted stream beds. About 1/8th of grouted streams are re-grouted when the first grouting is not effective.
“Synthetic stream liners were employed in two places on Polen Run for which grouting was predicted to be ineffective, for a total of 4,500 ft of liner installation.
“Alluvial amendments using bentonite clay were employed on five streams during the 5th assessment period, covering 8,925 ft of stream bed.”
The report also found, “Groundwater monitoring is conducted quarterly. This schedule does not capture changes in groundwater occurring during undermining that can be reliably compared with related changes in surface water conditions.
“This limits evaluation of subsidence effects on groundwater and the associated impact to surface waters. Most of the water sources used for 92 augmented streams were groundwater sources.”
Water Supplies Impacts
The report found 379 water supplies were affected underground of which 192 were determined to be the mining company’s fault and 73 were categorized as interim resolutions. There were 2,353 water supplies undermined in all during the reporting period
Of those affected, 25 percent were impacted by pillar recovery, 18.9 percent by room-and-pillar mining and 14.1 percent were impacted by longwall mining.
Of the 192 water supplies affected, mining companies took an average of 426 days to resolve the issue and 150 days if the company purchased the property affected.
Of those water supplies not the fault of mining companies, it took an average of 154 to resolve and withdrawn claims took an average of 303 days.
Fifty-four percent of all company-liable water supply effects were settled through an agreement between the mine operator and the property owner.
Structural Damage
Of the 3,612 structures undermined during this period, there were a total of 391 effects from active mines and an additional 64 reported impacts from mines there were in active during 2013-2018 totalling 455 structures.
Of the 455, 247 structures-- 54 percent-- were found to be the mining company’s fault with the remaining 208 reported effects had a company not liable resolution or are still in interim resolution (109).
The most commonly undermined structures were homes.
The average time for all structural final resolutions was 162 days. This is down slightly from previous reports.
Wetlands Damage
An estimated 90.7 acres of wetland habitat were undermined and of the five longwall mines reporting pre- and post-mining wetland acreage, only one mine reported a loss of wetlands acreage, the others reported a slight gain due to stream and other changes to the landscape.
Enlow Fork reported the loss of 27.2 acres of wetlands which represented 25 percent of the pre-mining wetland acreage during the 2013-2018 reporting period.
The Dutch Run and Whiteley Creek mitigation projects were implemented to compensate for losses over Cumberland mine during the 4th assessment and created 5.08 acres of wetland, less than the mitigation target of 6.19 wetland acres.
Recommendations
The University of Pittsburgh made a number of recommendations about improving the quality and format of data collected by DEP and analyzed for this report and other observations from its review of the information gathered during the reporting period, including--
-- Damage Is Occurring At Distances Beyond What Is Expected: “... during this assessment, unexpected impacts were observed. Far-field subsidence impacts occurred at distances well beyond those predicted by models accepted by the ground control scientific and engineering community.
“Company liable subsidence impacts occurred over inactive mines. These cases, if rare, might be aberrations. However, multiple far-field effects were recorded at distinct mines. Evaluation of whether these cases are “noise” or indicative of important emergent processes to consider fundamentally require a holistic approach.”
-- Comprehensive Evaluation Of Subsidence Impacts Needed: “Attempts to simplify management of subsidence need to be coupled with comprehensive examination of the larger implications.
“For example, PADEP and the mine operators have developed effective means to ensure most individual landowners are compensated for damage to their property from subsidence impacts. This is a strength of the program.
“However, this focus on parcels may be missing important transformations on the larger landscape as operator purchases of undermined properties alter fundamental land uses. These are trends that can only be discerned by stepping back and examining the mitigation in aggregate.
“The need to comprehensively examine subsidence impacted systems is probably most pressing in hydrologic systems. Policy on surface water repair has matured into a process centered around stream recovery evaluation reports.
“However, while the PADEP collects data on both groundwater and wetland systems, these data are rarely integrated into assessments of hydrologic impact and repair. A test for groundwater impairment is not clearly defined. (e.g., In surface water systems, changes in the range of flows are evaluated with data collected from defined time frames relative to mining.”
-- Hard Copy Data: Most data submitted to DEP Stream Recover Evaluation Reports and Hydrologic Monitoring Reports is still either hard copy or on compact discs in spreadsheet files as part of permit files and are relatively inaccessible.
-- Outdated Database Systems: The Bituminous Underground Mining Information database system used by DEP is over 25 years old and gathering and QA/QC checking remains the largest portion of the total University effort on this project.
Visit DEP’s Act 54 Mining Reports webpage for a copy of this report and previous Act 54 reports.
CAC Review
DEP’s Citizens Advisory Council will now will have the opportunity, under Act 54, to review the report and make recommendations on changes to DEP’s policy and regulations based on its findings.
In 2015, when the last report was completed, the CAC held a formal comment period on the report and a hearing in the affected area to gather public comments.
The Council then sent comments and recommendations on the report’s findings to DEP for its review.
For more information, visit the DEP Citizens Advisory Council webpage. Questions on the CAC’s review should be directed to Keith Salador, Executive Director, by calling 717-787-8171 or sending email to: ksalador@pa.gov.
(Photos: top left/middle - impact of heave on Whitethorn Run over Bailey Mine and stream after heave cut was made; top right- damage to home by Enlow Fork Mine; bottom left- mitigation for gas line over Enlow Fork Mine; bottom middle- mitigation trench dug around a home over Contura Mine; bottom right- timber bracing used to stabilize structure during mining.)
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[Posted: December 23, 2019] www.PaEnvironmentDigest.com
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