Matt Naud, the city of Ann Arbor's environmental coordinator, points to his home on a 3D map of the Pall-Gelman 1,4 dioxane plume. The map was constructed by Roger Rayle, a leader of Scio Residents for Safe Water, who brought it to the March 30 public meeting about a new consent judgment related to the plume. (Photos by the writer.)

Mitch Adelman, a supervisor with the Michigan Dept. of Environmental Quality’s remediation division, began the March 30 meeting by acknowledging the crowd’s reaction to the new agreement, which was issued earlier in the month without opportunity for public input. “I don’t expect anything I say or do tonight to alleviate your anger or frustration,” he said.

But Adelman noted that if a company like Pall – which owns the former Gelman Sciences site – proposes a remediation plan that complies with state law, “we’re obligated to accept it.”

For nearly three hours, Adelman and Sybil Kolon, MDEQ’s project manager for the Pall site, gave an update and answered questions about the new consent judgment, the history of the cleanup, and what residents might expect in the coming years. They were challenged throughout the evening by people who’ve been following this situation closely – most notably by Roger Rayle, a leader of Scio Residents for Safe Water and member of the county’s Coalition for Action on Remediation of Dioxane (CARD). Rayle has been tracking the dioxane plume for many years, and presented his own graphical renderings of data to the group.

The meeting was attended by several elected officials: Ann Arbor city councilmembers Stephen Rapundalo (Ward 2) and Mike Anglin (Ward 5); Ann Arbor Township supervisor Mike Moran; county commissioner Yousef Rabhi (District 11); and Sarah Curmi, chief of staff for state Sen. Rebekah Warren, whose district covers a large portion of Washtenaw County, including Ann Arbor and Scio Township, where the plume is concentrated.

1,4 Dioxane Plume: 40+ Years

In the 1960s, Gelman Sciences – a firm founded by Charles Gelman that manufactured medical filters and other microfiltration products – began pumping industrial wastewater into holding lagoons behind its factory at 600 Wagner Road in Scio Township. Some of those wastewater releases were permitted by the state. Contaminated groundwater leeched into underground aquifers, and by 1985, tests showed some local residential wells were contaminated with 1,4-dioxane, a substance that’s considered a carcinogen.

In 1988, the state filed a lawsuit against the company to force a cleanup. A consent judgment in the case was issued in 1992 by the Washtenaw County Circuit Court, setting out terms for handling the cleanup. The consent judgment has previously been amended twice – in 1996 and 1999. In addition, the court has issued several other cleanup-related orders, including a 2005 order prohibiting groundwater use in certain areas affected by the dioxane plume. The city of Ann Arbor filed a separate lawsuit in 2004, which was settled.

Building 1 at the Pall Corp. facility in Scio Township. No manufacturing is done now at the former Gelman Sciences plant, but a water treatment facility is located on the site to remediate 1,4 dioxane groundwater contamination.

Meanwhile, in 1997 Gelman Sciences was sold to Pall Corp., a conglomerate headquartered in East Hills, N.Y. – the local operation became part of a subsidiary, Pall Life Sciences. In 2007, Pall closed the manufacturing plant on Wagner Road, where the contamination originated. However, a groundwater treatment facility continues to operate there, as part of the court-ordered cleanup effort that’s directed by the state Dept. of Environmental Quality.

In late 2008, Pall asked to revise terms of the consent judgment. A proposal was brought forward by the company in 2009 – in May of that year, the state held a public meeting to discuss the proposal. That was the last time the state has held a public meeting on the topic, until the March 30, 2011 meeting at Abbot Elementary.

The MDEQ rejected Pall’s proposal in June of 2009. But later that year, Washtenaw County Circuit Court judge Donald Shelton ordered the two parties to work together and present a proposal for a third amendment to the consent judgment.

There was no opportunity for public input during the period when Pall, MDEQ and the court were discussing possible changes to the consent judgment, and those discussions were not held in public. Roger Rayle, a Scio Township resident and leader of Scio Residents for Safe Water, has been speaking out against this process for months. Rayle, who is also a member of the county’s Coalition for Action on Remediation of Dioxane (CARD), alerted county commissioners about the situation at their Feb. 3, 2011 working session. At the time, he told commissioners, “If it doesn’t involve your district now, it will.”

In early March of 2011, Shelton ordered a change in the terms of the consent judgment, including some aspects that had previously been rejected by the state. [.pdf file of March 2011 amendment to the Pall-Gelman consent judgment. Additional related documents are available on the CARD website. The MDEQ also maintains a website specifically for information related to the Pall-Gelman site.]

Pall Consent Judgment

Much of the March 30, 2011 meeting was spent providing background on cleanup efforts and describing elements of the amended consent judgment.

Mitch Adelman of the Michigan Dept. of Environmental Quality’s remediation division told the crowd that the basis for making amendments to the consent judgment stems from Part 201, Section 2a of the state’s Natural Resources & Environmental Protection Act (NREPA). The relevant part of Section 2a states:

(3) Notwithstanding subsection (1), upon request of a person implementing response activity, the department shall approve changes in a plan for response activity to be consistent with sections 20118 and 20120a.

What this means, Adelman said, is that the MDEQ is required to approve changes to legal agreements that meet the requirements of Part 201, as amended. When the MDEQ rejected Pall’s proposed changes in 2009, he said, the company went to court to get it approved, claiming that its plan met state requirements. Adelman said the court has made several rulings in connection with this particular cleanup effort, and “frankly, some of the rulings haven’t been favorable to us.”

The MDEQ had rejected the plan in 2009 for several reasons, Adelman said. The proposal lacked an adequate monitoring plan and contingency plan for dealing with the plume’s possible spread, and there was uncertainty about both the plume’s migration pathways and its current location.

The state’s primary concerns related to protecting of Barton Pond – where the city of Ann Arbor gets 80% of its drinking water – as well as protecting nearby residential wells. There was also the potential that dioxane standards might be changed. Adelman said there’s information from the U.S. Environmental Protection Agency (EPA) that might result in lowering the state’s current standard of allowing up to 85 parts per billion (ppb) of 1,4 dioxane in drinking water – which in turn could result in a stricter cleanup requirement. [By way of comparison, when the local 1,4 dioxane contamination was first discovered in the 1980s, the acceptable level in Michigan was just 3 ppb.]

Other concerns cited by Adelman were: the general protection of public health, safety, welfare and the environment; the proposal’s enforceability; and financial assurance from the company that they’d be able to carry out the cleanup to completion.

Adelman and Sybil Kolon, MDEQ’s project manager for the Pall site, described some of the changes made in the amended consent judgment. They include:

Map of expanded prohibition zone, where residents are prevented from drinking well water that might be contaminated by 1,4 dioxane. The green line indicates the previous area in which residents are prohibited from drinking well water. The red dotted line indicates the expanded zone. (Links to larger image.)

• Expansion of the so-called “prohibition zone.” This is an area where higher levels of 1,4 dioxane are allowed – up to 2,799 ppb – and where property owners are banned from using wells for drinking water. Because property owners in the zone can’t use their wells, they are required to hook up to the city water and sewer system, if they aren’t already connected. Pall covers only part of that expense. The zone is expanded to the north of the current boundary into the Evergreen subdivision area in Ann Arbor. [.pdf of expanded prohibition zone]
• Negotiation of deed restrictions on properties in certain areas outside the prohibition zone, in locations where 1,4 dioxane has been detected. The deed restrictions, to be negotiated between Pall and the property owners, would prevent the use of well water on those properties.
• Installation of additional groundwater monitoring wells by Pall to define and monitor the plume.
• A reduced rate of groundwater extraction by Pall at several locations, but with continued treatment and discharge to the Honey Creek tributary. The groundwater extraction can be terminated with MDEQ approval. Five active extraction wells east of Wagner Road will be decreasing their extraction rate from 500 gallons per minute (gpm) to 300 gpm. Twelve extraction wells west of Wagner will decrease their rate from 675 gpm to about 400 gpm.
• Continued monitoring by Pall of groundwater contaminated with 1,4-dioxane that exceeds the generic residential cleanup criterion of 85 parts per billion, until Pall can demonstrate the remaining groundwater contamination does not pose an unacceptable risk to human health, safety, welfare or the environment, now or in the future. There are 120 monitoring wells west of Wagner Road – of those, 88 are tested annually, 19 are tested semi-annually, and 13 are tested quarterly. East of Wagner, 107 monitoring wells are in place – 23 tested annually, 23 tested semi-annually, 53 tested quarterly, and 8 tested monthly. [.pdf map of monitoring well locations]

The previous consent judgment required full cleanup.

Dioxane Plume: Q&A

Over the course of the three-hour meeting, residents who attended asked a range of questions about the contamination and cleanup. Here’s a summary of the Q&A.

What’s the process of identifying wells that need to be “plugged” in the prohibition zone?

Kolon explained that some homes that are now a part of the city, located west of Maple Road, were originally in Scio Township – in the past they were not hooked up to city water. Subdivisions were platted in the 1920s, with homes built in the 1930s. Pall will survey those properties, she said, to check if wells are still in use. It won’t be a forced inspection, she added – they hope people will voluntarily allow the inspections, which Kolon said she would oversee. If property owners in the prohibition zone know of other wells that haven’t yet been plugged, they should come forward. She conceded that the process hasn’t gone as smoothly as they would have liked.

Who pays for wells to be plugged and homes hooked up to city water and sewer?

Kolon said it’s the state’s position that Pall should pay. But the company has asserted that if a well hasn’t been used for a certain period of time, it shouldn’t be their responsibility to plug it. The state will nevertheless ask Pall to pay for plugging all wells, Kolon said. “We hope we won’t have to go to court about that.”

A resident noted that Pall is paying only to hook up homes to city water service – the property owners have to pay for sewer hookup. “So what kind of deal is that?” he asked. “Sounds like Pall’s got us by the balls.” [The properties would also be annexed to the city of Ann Arbor, which means that property owners would pay Ann Arbor taxes – higher than taxes in the township.]

Kolon replied that at some point, those homeowners would have to hook up to the city’s water and sewer system anyway. State law requires that Pall pay only for the water service hookup.

Who’s monitoring the Pall-Gelman site to ensure they aren’t continuing to contaminate the water?

The company stopped using 1,4 dioxane in 1986, Kolon said. Now, there’s no manufacturing at all at that location.

What’s the status of monitoring the plume’s possible migration north, to Barton Pond?

Kolon said the MDEQ believes there will be adequate monitoring wells in place to detect possible migration. If monitoring wells to the north detect water with more than 20 parts per billion of 1,4 dioxane, then the company must investigate the situation, and possibly conduct a feasibility study to determine how to address the contamination.

A crowd gathers at Abbot Elementary School for a March 30, 2011 public meeting on the Pall 1,4 dioxane plume.

When a resident questioned the wisdom of having the company that’s responsible for the contamination also be responsible for monitoring it, Adelman said the MDEQ is overseeing the monitoring process. In the past, when split samples have been analyzed by both the company and the state, the results have matched up, he said. In response to another question, Adelman said there’s been no evidence that Pall has hidden results from a certain monitoring well.

Vince Caruso, a member of the county’s Coalition for Action on Remediation of Dioxane (CARD), said that they’ve discussed at CARD meetings the fact that there are competing analyses of the direction of water flow toward Barton Pond. A Michigan State University study leads them to believe the flow could move to Barton Pond – and if it moves too far, it may be too hard to contain, he said. Caruso also was concerned about contaminated groundwater getting into the basements of homes.

Adelman said the state shares that concern about Barton Pond – that’s why there’s a monitoring plan and wells in place, he said. Caruso indicated that it’s not reassuring to see the prohibition zone extended to the north.

Mike Gebhard, an environmental analyst with Washtenaw County, pointed out that not enough is known about the area’s geology to determine how the plume might spread. Originally it was thought that a protective layer of clay would prevent the plume from spreading east, but that didn’t stop the migration of contaminated groundwater.

Gebhard also noted that the monitoring wells on the northern boundary of the prohibition zone are – at their closest – 1,000 feet apart from each other, and sometimes much farther apart than that. It’s not a tight monitoring network, he said. He also observed that there’s no contingency plan in place if cleanup efforts fail and migration of 1,4 dioxane continues to Barton Pond.

How are residents notified that their homes are in the prohibition zone?

Over 4,000 parcels are located in the original prohibition zone, and neither Pall nor the state were required to contact each residence individually, Kolon said. The same is true for the roughly 400 parcels in the expanded zone. Notices about public meetings are published, but there are no direct mailings to residents.

How are deed restrictions on properties handled?

Deed restrictions, which would prohibit the use of wells for drinking water, will be negotiated between Pall and the property owner, Kolon said. The MDEQ is not involved. If a property owner doesn’t agree to Pall’s offer, it’s possible that the company could take the property owner to court to mandate a deed restriction.

How much 1,4 dioxane is in the plume?

State officials said it’s difficult to say how much wastewater was released over the years, and how much 1,4 dioxane remains underground, or where exactly it’s located. The amount of acceptable levels of 1,4 dioxane has also changed – when the contaminant was first discovered in local drinking water, the state’s criterion for acceptable levels was 3 parts per billion (ppb). That level has been raised to 85 ppb. A much greater geographic area contains 1,4 dioxane in levels below 85 ppb, but the state can’t require Pall to remediate those lower levels. And in the prohibition zone, up to 2,799 ppb is allowed. There are currently pockets where levels are higher levels than that – in the 3,000 ppb range. Those areas are being remediated.

What’s the difference between mass removal and full cleanup?

Full cleanup means decreasing the level of 1,4 dioxane to 85 ppb, Adelman said. For mass removal, there’s no strict standard, he said – Pall will continue to extract contaminated water, treat it, then reinject it into the ground or into the Honey Creek tributary. In the prohibition zone, up to 2,799 ppb of 1,4 dioxane is allowed in the groundwater. Over time, concentration levels have decreased in many areas, Adelman noted.

He clarified that “mass” refers to actual 1,4 dioxane. Kolon added that to date, 64,000 pounds of 1,4 dioxane have been removed from groundwater.

How much 1,4 dioxane remains underground, and how will Pall or the state determine when cleanup is complete?

When asked how much 1,4 dioxane is left, Kolon said they don’t know. Adelman noted that Pall has already removed more 1,4 dioxane than they originally predicted was underground.

There are 17 active extraction wells, from which Pall is removing contaminated water, treating it and reinjecting it into the ground or into a Honey Creek tributary. All extracted water is treated using ozone and hydrogen peroxide to destroy most of the dioxane, according to Kolon. The water that’s discharged to the Honey Creek tributary contains a monthly average of 7 ppb. Extraction wells are tested monthly. However, despite the extraction, the plumes are as big as they were roughly 15 years ago. And under the amended consent judgment, the amount of extraction will decrease.

Pall has cleaned up a lot, Kolon said, but a lot has migrated – “it moves wherever the groundwater takes it.” At some point, though, Pall will determine that they’ve removed enough 1,4 dioxane so that the plume won’t expand, and they’ll ask the state for permission to stop. If the state grants that permission, Kolon said, Pall would still be required to continue long-term monitoring for at least 10 years, and probably longer.

What happens if your property is outside the prohibition zone, but you have water with over 85 ppb?

Adelman said the county wouldn’t permit you to drill a well under those circumstances. “So those people are screwed,” the resident replied.

Why didn’t the state refuse to negotiate a new plan with Pall?

Adelman said that if they had denied the plan again, Pall would have asked the court to force the state to adopt it – and the company could have won. It was the collective opinion of MDEQ staff and a representative from the attorney general’s office, he said, that the court could impose something worse than what the state could negotiate. What they got isn’t perfect, he added, but it’s better than it might have been.

In the worst-case scenario, when will the contamination reach the Huron River?

Mike Gebhard, an environmental analyst with Washtenaw County, calculated that it could take 10-15 years or less. He said there aren’t enough monitoring wells in place at this point to get an accurate picture of where the flow is headed, and how fast.

What happens if Pall goes out of business?

Until this latest amendment to the consent judgment, there were no provisions for that possibility, Kolon said. Now, the state is getting a corporate guarantee from Pall, based on a five-year projection of their costs to operate the cleanup. Pall is doing quite well, she noted, but if things change and the company goes out of business, the state would get funds to run the cleanup. [In early March 2011, Pall reported a 52% increase in second-quarter earnings to $75.7 million, and a 15% jump in revenues to $645.2 million.]

What happens if the state reevaluates and lowers the current acceptable level of 1,4 dioxane, which is set at 85 parts per billion?

Adelman said the new consent judgment has a provision that allows the state to reopen that issue. If lower standards are put in place – when the 1,4 dioxane was originally discovered in this area, the state limit was 3 ppb – then the MDEQ could petition the court to require Pall to clean up groundwater to that new level, Adelman said. However, there’s no guarantee the court would agree to that change.

Could Pall ever be required to install equipment in the city of Ann Arbor’s water treatment plant that would remediate 1,4 dioxane?

Kolon said there have been some discussions of that possibility in the past. Adelman added that the state hasn’t pushed for it because it might be interpreted as accepting a scenario in which the city’s water source at Barton Pond gets contaminated.

As a taxpayer, why should I be happy about this?

Adelman said they weren’t saying that people should be happy. The state had to approve a proposal that complied with the law, he said. “Should you be happy? If I were you, I don’t think I would be.” He said he wasn’t going to try to sugarcoat the changes, but that it was the best they could do, given the constraints.

General Public Commentary

In addition to asking questions, several residents who attended the March 30 meeting leveled criticisms against the company, the court and the state, especially related to the process of amending the consent judgment.

Roger Rayle, a Scio Township resident who's been tracking how the state is overseeing Pall's 1,4 dioxane plume cleanup for many years, videotaped the March 30, 2011 public meeting held by MDEQ staff at Abbot Elementary School.

Roger Rayle, who videotaped the meeting, noted that the last public meeting was held in 2009. Based in part on public input from that meeting, Pall’s proposal was rejected by the state. But this time, he said, public input has been ignored. The county’s Coalition for Action on Remediation of Dioxane (CARD) meets regularly – those meetings are open to the public – but their input has been ignored as well, Rayle said. Now, without public process, much of Pall’s proposal has been codified. He said he wasn’t blaming Adelman or Kolon personally, but they are agents of the state. The outcome is not good for the state of Michigan, and that’s not good for protecting the Great Lakes, which contain 20% of the world’s fresh water.

Rayle said the fact that Judge Shelton didn’t see all the facts related to the plume is a problem. “It’s not that the foxes are in charge of the henhouse,” he said. “The foxes are architects of the henhouse.”

Pat Ryan, an Ann Arbor resident, told the group that everyone should know how important it is for the community to be vigilant about this situation. Citizens need to be talking to state officials as often as the company does, she said. She noted that Washtenaw County isn’t at the vanguard of regulatory deterioration – “we’re just joining the rest of the state.”

Yousef Rabhi – a county commissioner who represents District 11, an area covering southeast Ann Arbor – told Adelman and Kolon that at the end of the day, they worked for the public. He said it’s incumbent on citizens to elect people at the state level who’ll represent their interests when it comes to issues like environmental protection. Rabhi, who is the county board’s liaison to CARD, urged people to contact their current state officials – it’s important to hold them accountable. When he noted that he didn’t think his district was affected by the plume, someone in the crowd shouted out, “It will be!”

Coda: April 5 CARD Meeting

Rabhi also was among a much smaller group who attended the most recent meeting of the Coalition for Action on Remediation of Dioxane (CARD), held on Tuesday, April 5. CARD is a coalition of citizens and local governments – including the county – that’s focused on addressing the 1,4 dioxane problems.

An April 5, 2011 meeting of the Coalition for Action on Remediation of Dioxane (CARD). Clockwise from left: Sybil Kolon, project manager with the Michigan Dept. of Environmental Quality; Washtenaw County commissioner Yousef Rabhi; Ann Arbor Township supervisor Mike Moran; Mike Gebhard, Washtenaw County environmental analyst; Vince Caruso of the Allen Creek Watershed project; Matt Naud, city of Ann Arbor environmental coordinator; and Gordon Bigelow, Ann Arbor resident. Obscured from view is Roger Rayle, a leader of Scio Residents for Safe Water, and Rita Caruso, who serves on the Ann Arbor environmental commission.

This was the first meeting since news that the amended consent judgment had been signed, though members had known it was in the works. Kolon also attended, and many of the questions posed by CARD members dealt specifically with terms of the amended agreement. Some people at the meeting expressed a certain amount of resignation that, since it was a done deal, there’s very little room for input. Mike Moran, Ann Arbor Township supervisor, noted that nearly every item that’s stipulated in the consent judgment also allows for the possibility of dispute resolution – that means whenever Pall wants to change the terms, they can make that request to the court.

Mike Gebhard, an environmental analyst with the county who led the CARD meeting, opened the discussion by saying they hoped to ask questions of Kolon about the consent judgment and its interpretation, and to get a sense of “where we fit in.”

The Chronicle was unable to stay for the entire April 5 CARD meeting. In a phone interview the next day, Matt Naud – the city of Ann Arbor’s environmental coordinator – said the meeting primarily offered CARD members a chance to ask questions about the consent judgment, since MDEQ staff hadn’t previously been able to talk about the agreement while it was being negotiated. He said Rabhi had suggested that CARD compile a list of all the issues they would like to see addressed, if given the opportunity. That’s an action item they’ll pursue.

For example, in 2009 a consultant hired by the city of Ann Arbor proposed putting two additional wells on the north boundary of the prohibition zone, to provide data that could help determine where the plume is flowing. Those wells aren’t required as part of the consent judgement.

Naud noted that historically, another challenge has been that Pall has greater resources on its side, including well-paid attorneys, while the state relies on MDEQ and the attorney general’s office. At the April 5 meeting, some members discussed the fact that the attorney general’s staff hasn’t been well-prepared when in court to argue for tighter regulation of the cleanup.

CARD plans to continue to meet. MDEQ staff and CARD’s technical group are tentatively scheduled to meet next on April 27 at 9 a.m. at the Washtenaw County Western Service Center, 705 N. Zeeb Rd. Check CARD’s website for confirmation of the meeting date and time.

Argo Dam headrace closure. Without the metal plate, water would flow from left to right (bottom to top) in the photograph. The greenish metal plate is wedged into the concrete slot in shim-like fashion. The slot continues along to the bottom of the channel. (Photo by the writer).

The city of Ann Arbor and the Michigan Department of Environmental Quality have moved towards resolving a dispute about what needs to be done to address problems with the earthen embankment next to Argo Dam. Late this summer, the MDEQ had issued an order to the city to close off the flow to the headrace and dewater it by Nov. 1. That order was based on concerns about the structural integrity of the earthen berm dating back several years.

The city had retained the law firm Bodman, LLP on the matter, and filed a contested case with the MDEQ, asking for a 90-day stay on the MDEQ’s order, which includes a stoppage of flow in the headrace, and its dewatering.

The order also includes other points, among them a need for the city to make a decision on the dam-in/dam-out question. Whether to keep Argo Dam in place or remove it has been the focus of community-wide conversation on that topic, which has taken place with great intensity over the last nine months, but which has a years-long history.

The MDEQ agreed to the city’s request for a stay on all elements of its order except for shutting the water flow to the headrace. The city has now complied with the MDEQ’s order to close the headrace.

To the left of the green metal plate is the pond-side water level. To the right is the headrace side. The photograph, from the perspective looking down into the headrace gate, was taken about an hour after installation, and shows that the water level in the headrace is dropping. (Photo by the writer.)

Installation of the Plate

Responsibility for the dam at the city falls to Sumedh Bahl, the unit manager for the city’s water treatment plant. In a phone conversation with The Chronicle, he reported that earlier today around 10 a.m., city workers wedged a metal plate into a concrete slot to stop the flow of water to the headrace.

By the time The Chronicle arrived on the scene, around an hour later, the difference in water levels between the pond side of the plate and the headrace side was already visually apparent. The headrace level looked about two inches lower than the pond level.

Asked for details on the installation of the steel plate, Bahl said that it wasn’t the first time it had been installed – city staff practice that sort of thing on a regular basis. The plate itself was given a fresh coat of paint a few weeks ago in preparation for installation. The color change from orange to green was not aesthetically driven, he said. It just needed a new coat of paint to protect against rust.

Although the water level in the headrace is projected to drop a few feet over the next few days as a result of the outflow near the canoe portage, some water will remain. Removal of that additional water is what the MDEQ’s order to “dewater” affects – and the city now has a 90-day stay on that order.

MDEQ, City of Ann Arbor: Towards Resolution?

Speaking by phone to The Chronicle this morning, Byron Lane, head of dam safety for the MDEQ, said that the city of Ann Arbor’s rationale for requesting the 90-day stay and the MDEQ’s decision to grant it was based on the possibility of gathering additional data on the stability of the earthen berm. The city has hired the firm Stantec to install three piezometers at different points along the berm to measure water pressures inside the earthen structure.

The most recent public action taken by city council was consideration of a resolution brought at its Oct. 19 meeting to perform the maintenance on the earthen berm that the MDEQ has asked the city to complete.  That resolution was ultimately tabled, due in part to confusion about whether the intent of the resolution was to decide the dam-in/dam-out question, as well as have the maintenance performed.

Because it was understood by many to reflect a decision on dam-in/dam-out, the resolution was criticized for being introduced without a formal public hearing by the city council. Although there had been formal hearings by the park advisory commission, the environmental commission, as well as various public meetings and a council work session on the topic, there has not been a formal public hearing by the city council itself – something that city staff and community members had a working understanding would happen before a final dam-in/dam-out decision.

Based on city council deliberations at that their Oct. 19 meeting, there is a lack of enthusiasm for legal action as a preferred means of interacting with the MDEQ, and an interest in taking the measures necessary to satisfy the MDEQ’s concerns. But an item on the council’s upcoming Nov. 5 meeting agenda asks for approval of a contract with Bodman for $38,000 for work related to the MDEQ’s safety order.

Based on comments made by Christopher Taylor (Ward 3) at the Oct. 19 meeting, the tabled resolution from the Oct. 19 meeting could come back before council as a single resolution. That resolution would be to de-table the original resolution, amend it with more precise language making clear its intent, postpone it to a date certain, and hold a related public hearing on that date.

[The most recent earlier Chronicle coverage: "Finally a Dam Decision on Argo?" and "Still No Dam Decision"]

Likely point of closure for the millrace (also known as the headrace or canal) at Argo Dam. (Photo by the writer.)

As part of an intro to an interview with the chair of the Ann Arbor Park Advisory Commission, Scott Rosencrans, which The Chronicle published on Aug. 25, we reported that a letter from the Michigan Department of Environmental Quality had been sent to the city of Ann Arbor. The MDEQ letter included an order to close the millrace at Argo Dam.

The communication from the state agency didn’t come out of the blue – it was a reply to a request sent to MDEQ by the city of Ann Arbor asking for an extension to a July 31, 2009 deadline for action on Argo Dam.

With the text of both letters now available, we take a look at those communications, after briefly considering some historical context. That context dates back to a 2004 letter from the MDEQ about toe drains in the earthen berm next to the dam, and includes formation of a study committee, a public engagement process that extended over most of the first half of this year, recommendations from the city’s Park Advisory Commission and Environmental Commission, and a city council work session.

A key date from the most recent MDEQ letter is Nov. 1, 2009, by which time it has ordered the city of Ann Arbor to close off and drain the millrace. But it leaves both the dam-in and dam-out options available to the city. On a dam-in scenario, the MDEQ wants the toe drains in the earthen berm repaired by Dec. 31, 2010. On a dam-out scenario, the MDEQ wants the removal completed by December 2012. Either way, the city is supposed to have its study of options completed by April 30, 2010.

Based on a Tuesday phone conversation with Matt Naud, the city’s environmental coordinator, one possible timeline for next steps would have the city council conducting a mid-September work session on the topic, with clear direction coming at the council’s second meeting in September. Whatever that direction from council is, said Naud, it’s going to start costing money to implement the next steps – on the order of five-figure dollar amounts at least.

Background

The following timeline is not meant to be exhaustive, but does convey at least that the issue with the toe drains in the earthen berm (headrace embankment) adjacent to Argo Dam has been of concern to the MDEQ for a long time and that the city of Ann Arbor’s response has unfolded in the form of a task force, public engagement, and consideration by city commissions and the city council.

The two basic scenarios under consideration are these: (i) Dam-out – find an alternative venue for the rowers who use Argo Pond and remove Argo Dam, or (ii) Dam-in – repair the toe drains in the earthen berm adjacent to the dam and develop a program for maintenance of Argo Pond.

• 2001 Inspection report from MDEQ notes problem with toe drains in earthen embankment.
• Nov. 18, 2004 A letter from the MDEQ references the 2001 inspection report that first pointed out problems with toe drains: “The inspection report for the Argo Dam identifies problems that may threaten its safety. Specifically, the toe drains along the downstream side of the raceway canal embankment are failing. The toe drain failure is complicated by the dense growth of trees and brush on the raceway embankment and by the inability to block the flow of water into the raceway during an emergency. The toe drain system should be repaired immediately, and a means of blocking flow into the raceway canal should be devised as soon as possible.”
• March 2006 The city’s Environmental Commission creates the Huron River and Impoundment Management Plan (HRIMP) committee
• Sept. 12, 2007 The assessment of the dam’s condition and recommendations in the dam safety report includes: “The principal spillway and main embankment of the Argo Dam are in good condition. However, the headrace embankment is in poor condition. The dam has adequate spillway capacity to pass the design flood. The following recommended actions are listed by priority. (1.) Submit a copy of the contingency plan to block off flow from the millrace by February 29, 2008. (2.) Remove overhanging and dead trees from the headrace embankment by July 31, 2008. …”
• Dec. 26, 2007 A letter from the DEQ includes the following: “The headrace embankment of the Argo Dam is in poor condition, and the toe drains are not totally functional. This has been described in past reports, and you have received a permit to perform repairs to the toe drain system. It is our understanding that this work has not been done yet, and discussion is ongoing regarding the future disposition of the dam.”
• March 24, 2008 A letter from the DEQ includes the following: “One of the recommendations of this report was that a contingency plan be developed to rapidly shut off flow to the headrace in the event of concerns over the headrace. You provide this contingency plan to this office in your letter of February 21, 2008. The contingency plan lacks detail on how an actual or impending failure of the headrace embankment would be determined. … [P]lease be reminded that this headrace contingency plan is intended to be a short term plan to alleviate potential impacts caused by a headrace embankment failure. It does not address the significant structural concerns with the headrace embankment.”
• January-February 2009 City staff conduct a series of public meetings. [Chronicle coverage of a public meeting at Forsythe Middle School.]
• April 28, 2009 The final version of HRIMP report is finished. Key conclusion: “The decision at the Argo area comes down to one of community preference. Both options will require significant investment of capital and operation and maintenance dollars in addition to staff time.”
• May 19, 2009 The city’s Park Advisory Commission recommends on a narrow 1-vote margin to retain the Argo Dam. [Chronicle coverage of PAC Argo Dam discussion.]
• May 28, 2009 The city’s Environmental Commission recommends removal of the dam. [Chronicle coverage of EC Argo Dam discussion.]
• June 15, 2009 At a work session conducted by the city council, the apparent consensus was that staff should be directed to identify questions that would need to be studied for dam-in and dam-out scenarios and to ask DEQ for additional time.
• July 16, 2009 Ann Arbor sends a letter to MDEQ outlining specific areas of study for the dam-in and dam-out options, and asks for an extension of the deadline until April 2010.
• Aug. 6, 2009 MDEQ sends a letter in reply granting the extension, but ordering the closure and dewatering of the headrace.

Additional Chronicle coverage: “Huron River of Data” and “Dam Questions Dominate Caucus.”

City’s Letter: July 16, 2009

Discussion at the city council’s June work session reflected the fact that from this point forward, the city would need to start spending money – either for additional study or to implement a solution. And money spent on additional study could be allocated most efficiently by electing to explore primarily either a dam-in or a dam-out solution. Otherwise put, continuing to consider both alternatives equally would not be as cost-efficient as making at least a preliminary decision one way or the other.

So in the city’s response to the DEQ, specific relevant areas of further study were identified for dam-in and dam-out scenarios. In some cases there’s overlap. For example, both scenarios see detailed bathymetry as helpful. But on a dam-in scenario, the idea of that analysis is to create a baseline model for future sedimentation modeling; on a dam-out scenario, the idea of the bathymetry includes a model of the shape of the new river channel after dam removal.

From the city’s July 16, 2009 letter to the DEQ, here’s a list of the dam-in areas of study:

Dam-In Areas for Further Study

Sediment analysis – The City plans to undertake a sediment study to determine the extent of sediment and estimate future sediment management costs if the impoundment is preserved.

Detailed Bathymetry – The City plans to undertake a detailed bathymetric analysis of the impoundment to create a baseline model of the impoundment for future sedimentation monitoring.

Hydropower Options – The Veterans Administration is evaluating reintroduction of hydropower at one or more Ann Arbor dam(s) and we would like time to see how their interest develops and whether this interest and investment affects the decision by City Council.

Environmental Consequences of Impoundment Preservation – The city plans to review the available data and obtain new data in key areas to create a baseline for monitoring the impoundment effects on river water quality and ecosystem services.

Economic Consequences of Impoundment Preservation – From these studies, the city will estimate long-term dam maintenance costs and develop cost-sharing plans.

Outside Funding Sources – City staff will evaluate alternate funding sources for rebuilding the millrace to remove the canoe portage. Due to current economic conditions, any decision will be based on our ability to leverage outside resources so identifying viable outside funding sources is critical to any City Council decision. Recent federal support for the Great Lakes is a $400 million opportunity that we need to evaluate.

River Flow Evaluations – Variations in flow at the USGS gauge at Wall Street are of concern to MDNR and the city is evaluating mechanisms to reduce the variability from Barton and Argo to better meet run-of-the-river conditions.

From the city’s July 16, 2009 letter to the MDEQ, these are the dam-out areas of study:

Dam-Out Areas for Further Study

Sediment analysis – The city plans to undertake a sediment study to determine the extent of sediment affected by dam removal and estimate sediment management costs as part of this analysis.

Detailed Bathymetry – The City plans to undertake a detailed bathymetric analysis of the impoundment to answer several questions including the shape of the new river channel.

Detailed HEC-RAS model – The city plans to use the detailed bathymetry to develop a detailed HEC-RAS model to answer several outstanding questions including how the floodplain may change.

Rowing – Because the rowing community is most adversely affected by dam removal, City staff will be evaluating two alternative rowing venues to determine if they are viable sites for rowing. We believe that it will take some time to work out the details at one or more sites.

Environmental Consequences of Dam Removal – The city plans to review the available data and obtain new data in key areas to better understand the changes in river water quality and ecosystem services.

Economic Consequences of Dam Removal – Develop more detailed economic analysis of dam removal including new recreation opportunities and costs and reallocation of existing funding to other projects.

Outside Funding Sources – City staff will evaluate alternate funding sources for dam removal. Due to current economic conditions, any decision will be based on our ability to leverage outside resources so identifying viable outside funding sources is critical to any City Council decision. Recent federal support for the Great Lakes is a $400 million opportunity that we need to evaluate.

River Flow Evaluations – Variations in flow at the USGS gauge at Wall Street are of concern to MDNR and the city is evaluating mechanisms to reduce the variability from Barton and Argo to better meet run-of-the-river conditions.

MDEQ’s Letter: August 6, 2009

In the letter from MDEQ, dated August 6, 2009, the state agency orders the city of Ann Arbor to do the following:

1. On or before November 1, 2009, completely shut off the flow from the impoundment to the headrace and dewater the headrace. The headrace shall remain dewatered until the headrace embankment deficiencies have been corrected in a manner approved by the LWMD or the dam has been removed. The City shall continue to monitor the seepage emanating from the embankment at least monthly and notify this office if it worsens or is found to transport solids. This monitoring may be discontinued upon approval by this office, if the seepage ceases upon dewatering of the headrace.
2. On or before April 30, 2010, complete an evaluation of the options to address the deficiencies of the headrace embankment of the dam.
3. If the decision is made to keep the dam in place, all work to correct the headrace embankment deficiencies in a manner approved by the LWMD must be completed by December 31, 2010.
4. If the decision is made to remove the dam, the removal shall be completed by December 31, 2012. The City shall complete all necessary engineering design work for the removal and submit and application for the removal to this department by February 1, 2011.
5. The City shall submit reports on its progress to comply with this order annually by August 15 of each year until the deficiencies with the headrace embankment have been corrected.

The Nov. 1 deadline for closing the millrace (headrace) comes after the last date indicated on the city of Ann Arbor’s website for canoe rental from the city’s liveries, which is Sunday, Oct. 25, 2009. Through what little remains of this season, then, there might be little impact on the revenues about which Scott Rosencrans had expressed concern in his Aug. 20 interview.

Based on The Chronicle’s telephone conversation with Naud, closing off the millrace is fairly straightforward – a metal plate gets slid into place. But draining the millrace – or “dewatering” it, in the parlance of the MDEQ – is something that’s somewhat more complex, Naud said. The fact that the resulting empty millrace could pose a potential hazard to the public was, said Naud, “not a new thought.” Naud characterized how to deal with that – possibly through fencing it off – as a still-outstanding question. If a decision were made to fence it off, Naud said, it’d be a straightforward matter to calculate how much fencing was required and to price it out.

Naud sketched out one possible timeline for decision-making that would start the city in one direction or the other – at least in terms of what study options were pursued – on the dam-in dam-out question. That sketch would see the city council conduct a work session in mid-September on the dam question. Then at their second September meeting (Sept. 21) they might give some clear direction, say in the form of a resolution authorizing an expenditure.

If the city council does take up the topic of the dam at a September work session, it will need to add the dam to a joint work session already planned with the city’s planning commission to discuss zoning revisions (A2D2). At the city council’s last meeting, the idea of adding a discussion of council rules and ethics to the work session’s agenda was rejected.

Millrace at Argo Dam looking downstream from the point where the millrace allows canoeists to exit Argo Pond. (Photo by the writer.)

View from east to west. Canoeists currently paddle down the millrace from the right, and take their boats out of the water and down the steps indicated by the sign at the left. (Photo by the writer.)