I hope you are well. As you know I have taken a keen interest in the Toll Brothers site on Whitehall Road. I addressed the Board on this issue on May 6, 2016 during public hour (1).
I am writing to you today and cc’ing the Board and a number of others in leadership whom I have talked to in the last three weeks so that I might stress that going ahead with this development places the University at risk. I have been examining the available science (discussed below) and it all points to a fragile ecological area with connections to the well water.
I presented my assessment of the studies that have been done to the State College Borough Water Authority Board (SCBWA) last Thursday (6/15/17) and simply raised a number of concerns I had. Based on those concerns the SCBWA added new items to their Board meeting and agreed to look into conducting new studies on the Toll Brothers development site. In particular, a feasibility evaluation for doing a Dye Tracer Study was proposed and approved that would shed light on the statement by their current board member, and Penn State Extension Officer, Dave Yoxtheimer.
“The results of the dye tracing [on Slab Cabin run] provided independent evidence of the importance of subsurface flows in the transmission of water beneath the surface channel of Slab Cabin Run. This information lead to the conclusion that, in practical effect, there are two Slab Cabin Runs, one in the visible surface channel and another hidden from view in the shallow subsurface“ (2).
The movement by SCWBA is a clear indicator that the available science does highlight potential issues of risk with situating this large development so close to the well heads. This important move by SCWBA was noted at the Ferguson Township Board of Supervisors regular meeting on 6/19/17.
Let me repeat briefly the evidence I have reviewed that suggests future negative impacts on the two major wells. This is not my area of expertise so it is entirely possible I am mistaken so I have limited myself to the presentation of facts and direct quotes from the > 1,000 pages of reports and appendices. This is just an informational exchange to raise my concerns with you and the Board about possible risk.
The Toll Brothers site is in Zone 2 of two wells (Thomas and Harter Wellfields). These two wellfields provide >65% of the water for State College each day. The aforementioned tracer studies (November 2005 and December 2006, Ref 3) showed that a tracer dye (Sulphorhodamine B) released into Slab Cabin run upstream of well 11 (Thomas Wellfield) and 25 (Harter Wellfield) entered the wells in 5 days. Concentrations were different with higher levels in well 25 compared to Well 11 (82 ppb/day vs 1 ppb/day), implying different degrees of connection. Another dye (Fluorescein) released in a dry tributary (Musser Gap) feeding into Slab Cabin showed the dye arrived in Wells 11 and 25 between days 20 and 28 at similar concentrations (0.76 ppb/day and 0.56 ppb/day). Interestingly the dye was detected in Slab Cabin Run after 13 days at a concentration of 1 ppb/day. This according to the author of the report (Dave Yoxtheimer, Ref 2, Ref 3) highlights a complex subsurface flow captured in the above quote.
As a geologist you know that the reason for such interconnectedness is the karst and epikarst nature of the dolomite bedrock in our valley. Although this topography is well known, a repeated counter argument I have heard was that it is not a cause for concern as there is plenty of soil that would filter out any contaminants long before it reaches the wells.
To assess this, CMT Labs did the infiltration studies on the Toll Brothers site (Ref 4, Ref 5). These are discussed in the June 5, 2015 Final Stormwater Report (6). The site is dolomite rock with very shallow Hagerstown and Opequon soils. The 5.5 acres proposed to house the stormwater detention basin is on top of an exciting swale over a fracture zone. The area has extensive sinkholes. In preparing two reports on the infiltration studies CMT Labs had to do conventional and non-conventional infiltration tests because the soil was so shallow. It was necessary to also explore the capacity of the bedrock, which is very close to the surface and consists of fully exposed rock in some areas. The subsoils have “excellent structure/macropore abundance” but their “close proximity..to permeable bedrock” (Ref 4, p. 982) means the soil may not function as the filters such a site requires. That is, the stormwater may pass through the shallow soils into the sub-surface. As outlined above, the existance of a subsurface Slab Cabin Run connected to the wells means any pollutants from the site would also travel into the wells.
The two CMT reports are not confident in their assessment of the safety of this site and while they did not undertake a formal risk analysis, it is interesting how the report in 2013 (Ref 4) shifted from a safety recommendation of 2.0-2.5 to 3.0 in 2014 (Ref 5)
The reports raised a red flag about compaction. As you know (but perhaps the others cc’d here do not) the ability of soil to filter pollutants rests on the amount of natural holes it contains. Applying pressure to soil results in compaction which reduces its ability to act as a filter. In the first report, CMT Labs advocated that heavy equipment not be used during and after construction of the storm water capture basin. “All heavy equipment should be prohibited from operating or travelling over the infiltration pit” (Ref 4, p. 983)
Both reports (Ref 4, p. 984, Ref 5, p. 1041) expressed concern regarding the amount of mowing because of the compaction that could occur. Correct planting is needed but the timing of that and the first water to pond in the basin was a concern raised in the second report since there could be a “development of a restrictive layer” reducing infiltration capacity (Ref 5, p. 1041).
Taken together the soil analysis highlights a narrow layer, close to the bedrock that is liable to lose its filtration capacity, implying it is perhaps not the ideal location for a basin.
Soil is a natural filter and we can certainly use artificial filters if the soil is not sufficient. Engineering solutions such as a separation filtration are possible but the issue is that these “are prone to clogging over time, and may require long term maintenance. These issues should be discussed with appropriate municipal officials” (Ref 4, p. 982).
I have seen no plans for such maintenance or had evidence that these discussions with Ferguson Township occurred.
So far I have discussed the highly connected nature of the water and the insecurity expressed on the role that the shallow soils at the site can play in filtering the pollutants.
A major issue of course is that a sinkhole opens.
The CMT report states that the karst rock and its permeable bedrock mean “significant subsidence and sinkhole activity could occur” (Ref 4, p. 982).
Farming is the historic land use and it
“does not significantly increase the potential for sinkholes to form on this tract. The significant grading, landscape alteration, increase in impervious surfaces, and channeling of stormwater involved with this project [Cottages] does increase the risk of sinkhole formation and therefore does increase the potential to degrade ground water quality.” October 31, 2014 letter from Aqualith Technologies, LLC, (Author: David Yoxtheimer, now Penn State Extension).
“A sinkhole represents a direct conduit in to the aquifer which in turn could have direct adverse impacts on regional drinking water quality if significant volumes of surface runoff are channeled into a sinkhole. Based on the recent site walkover with the project engineers on October 23, 2014, and the site inspection by PA-DEP personnel (Kipp Starks, December 3, 2013) there are sinkholes in proximity to the project and therefore they do represent a risk. (October 31, 2014 letter from Aqualith Technologies, LLC, (Author: David Yoxtheimer, now Penn State Extension).
The 2014 CMT Lab report states:
“In terms of risk management, we do not believe there is an effective method for elimination of sinkholes in karst infiltration areas…and the risk is inherent” (Ref 5, p. 1034)
With such a large impervious surface planned at this site there exists the potential for marked changes in the pH to more acidic water in the runoff, accelerating erosion of the dolomite rock leading to sinkholes. I am certainly happy to provide references to other case studies where sinkholes formed under basins.
I am neither a hydrogeologist nor a geologist. I am an ecologist. But my reading of the available reports leads me to conclude that we do not have sufficient evidence to state that the placement of this development so close to the major wells is not without risk. The question for us, Penn State, is how much risk are we willing to accept?
My interest is protecting the mission of our University and the noble aims laid out in our strategic plan to be good stewards.
You may have heard that the Supreme Court of PA recently established (June 20) a broad interpretation of the Environmental Rights Amendment (Article 1, section 27) to the State Constitution, cementing in place the Commonwealth’s role as trustees for public natural resources. The Constitutional amendment states:
Pennsylvania’s public natural resources are the common property of all the people, including generations yet to come. As trustee of these resources, the Commonwealth shall conserve and maintain them for the benefit of all the people. The people have a right to clean air, pure water, and to the preservation of the natural, scenic, historic and esthetic values of the environment.
This Supreme Court of PA ruling sets aside 40 years of more restrictive interpretations. This is important here because the water in these wells is a common resource. We, as a Land Grant, have embraced the Environmental Rights Amendment, which we quote in our strategic plan.
I would also draw your attention the Community Bill of Rights adopted by Ferguson Township which states:
“Right to Pure Water. All residents, natural communities and ecosystems in Ferguson Township possess a fundamental and inalienable right to sustainably access, use, consume, and preserve water drawn from natural water cycles that provide pure water necessary to sustain life within the Township.” Section 1.05
Finally, were Toll Brothers plan to be put forward today it would not be compliant with the current stormwater management plan. I have heard the argument that their plan went above and beyond what was required and thus is safe. I have seen no evidence of this and would point out that if they submitted the same plan today it would not be compliant with regulations in place to protect water.
I do not know if we (Penn State) can reasonably state that in selling this land we have no responsibility should the wells get contaminated. But perhaps it is best to observe the precautionary principle and find an alternative solution.
Last Saturday I drove around for 3 hours with a local developer and it is clear there are many sites near the University which we could sell to Toll Brothers. I am happy to provide maps highlighting where these are.
In conclusion, it is my view that proceeding with the sale to Toll Brothers represents a risk to the University. This is certainly in terms of our reputation in this community but may be a broader risk as we are the State’s Land Grant and have responsibility to be stewards of our natural resources.
I am happy to serve you or the Board in any way I can as we navigate this issue.
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