Archive for the ‘Herbicide’ Category

State Extends Restrictions Further Downstream

Wednesday, June 9th, 2010

Because the concentration of triclopyr tested at 0.015 ppm 0.9 miles downstream from the lake 24 hours after the chemical was applied, the Vermont Department of Environmental Conservation has extended the water use restrictions already in place an additional mile downstream on the Ompompanoosuc.  We will be notifying the abutting landowners and posting some more signs.

It should be noted that the concentration found which caused this late change was 0.015 ppm, which is well below the 0.075 ppm which is considered safe for drinking water.  The scientists at the State seem to be concerned that this is an early indication and that the downstream levels might rise.  We will be adding an additional testing location further downstream for the next round of testing.

~ ~ ~ ~ ~ ~ ~ ~ ~ ~

Here is a map that shows how far downstream the additional restriction will extend.  Note the darkened portion of the Ompompanoosuc.

Click for larger map

First Testing Results In

Wednesday, June 9th, 2010

On Thursday, June 3rd, 24 hours after we completed the chemical treatment of Lake Fairlee, we took nine water samples at designated locations around the lake and sent them to the lab for analysis. Because the lab will not start the 48 hour testing process on a Friday, the samples were submitted on Monday the 7th, and we just received the results today.

Click here for a larger image

Sample sites one through eight are located around the lake in representative areas that received treatment. Site nine is almost a mile downstream, where the creek that flows out of the lake runs into the Ompompanoosuc. (map)  The results (left column) range from .085 ppm to .930 ppm.  All but two of the results were .332 ppm or below.  No one has been able to explain just why two of the samples showed such high results, while the others were much lower.

The strength of the applied chemical was 1.5 ppm in the northeastern end of the lake, and 2.0 ppm in the southwestern.  For some reason the average concentration found by the tests was higher in the end of the lake in which the applied concentration was lower.   These are raw data and one can expect some variability in individual readings.  Nonetheless the concentration found at site #2 seems much higher than we were led to believe it should be, and out of line with the other samples.  We have asked the scientists with experience with these procedures for help understanding why there might be so much variation.

The immediate point of this testing is to let us know when we can lift the restriction on the use of lake water for drinking and preparing food.  The State will allow us to remove that restriction when the concentration at every location tested is below 75 ppb (which is .075 ppm).  We will keep you informed.

WARNING: Even when this restriction related to the treatment is lifted, we still do not think that drinking the water in the lake is safe, for a variety of other reasons.

Answering Every Concern

Saturday, June 5th, 2010

We are still receiving inquiries and complaints about our treatment of the lake this week.  One caller was clearly upset, having returned home to find that the treatment had already been done, and feeling that he had not had a say.  He is a resident of Thetford, and a regular user of the lake.  He had thought that there would be another hearing, or perhaps a town vote, before any action was taken.  I explained that the lake belongs to the State, which had the responsibility for the final decision to treat the lake. I told him that the lake association had acted because none of the three towns had wanted to be responsible for the treatment.

Part of his concern seemed to come from his belief that that triclopyr (the chemical we used) had been shown to cause harm to humans by the State of Washington.  I assured him that the State of Washington, or at least their Department of Ecology which is responsible for such things, had approved triclopyr for use in its water bodies.  I concluded that it seemed unlikely that they had also found any danger of harm to humans.

I did misinform him in one regard, however.  I asserted that I had put a link to Washington’s triclopyr information on this blog.  I correct that error now.  HERE is the relevant portion of their Environmental Impact Statement (EIS) for Permitted Use of Triclopyr.  It is a particularly comprehensive look at how triclopyr affects different plants, invertebrates, fish, birds, and animals.  Also how it behaves in soils, floods, surface water, and ground water.  I commend this resource to your attention.

On the other hand, we are receiving many more expressions of gratitude than criticisms.  More than a few have said “it’s about time.”

The Lake is Open for Fishing and Swimming

Friday, June 4th, 2010

Green tape on signs says "This Restriction has been Lifted" (click here)

In accordance with the terms of our permit, this morning we taped over three of the restrictive clauses on the warning signs around the lake.  The lake is now safe for all recreational uses, including swimming, boating, and fishing.  The lake water still may not be used for drinking or for food or drink preparation, nor for irrigation.  The other restrictions will be lifted when testing shows that the residual chemical has dissipated sufficiently.

The First Post-Treatment Water Tests

Thursday, June 3rd, 2010

Click for larger map

As required by our permit, 24 hours after the completion of the herbicide application we sampled the lakewater in eight locations around the lake and another downstream at the confluence of the outlet stream with the Ompompanoosuc River.  The locations were determined by the State, in consultation with Lycott Environmental. The water samples will be shipped to the SePRO lab for testing to determine the level of triclopyr in each.

The results of this test, and of others to come, will be used by the State to determine when the restrictions on our lake can be lifted.  The lake will be open for swimming, boating, and fishing tomorrow (Friday June 4th) but lake water may not be used for drinking and food preparation until the concentration of triclopyr is below 75 parts per billion.  (Does anybody really still drink from the lake?)  The results of this first test will be available next week, and will be published here.

~ ~ ~ ~ ~ ~ ~ ~ ~ ~

Four members of the Lake Association learned how to collect the samples properly.

Will explains the testing protocols

The water to be tested has to be collected from near the bottom of the lake, where the concentrations are highest.  At each of the sampling locations shown on the map the depth is indicated.  We learned how to get samples from the bottom four feet of water.

Skip lowers the Van Doren collector

Lycott provided a mechanical contrivance called a Van Doren collector to help in this task.  Sort of like a watertight animal trap, it can bring up a clean, uncontaminated sample from any predetermined depth.

Ridge retrieves a sample

The next sampling date will be determined after we receive the results of this first test.  Stay tuned.

Today is the Day!

Wednesday, June 2nd, 2010

The crew from Lycott Environmental arrived late Tuesday, about nine of them. They spent the night in camp tents provided by Camp Aloha Hive. More arrived early Wednesday, including two employees of SePRO, the company that manufactures Renovate OTF, the herbicide we are using.  In all there were thirteen people who would actually be handling the chemical.  Early Wednesday morning they began work.

Treatment Map

Weather later in the day promised to be fine, but thick fog blanketed the lake early.  Around dawn a small skiff was sent around the lake to place small orange buoys, using a GPS, to lay out the sections to be done in each batch.  Lycott had developed an elaborate plan that would efficiently use two boats to apply just the right concentrations in the areas of the lake where milfoil grows.  By about 7:30 am the whole crew was involved, setting up the boats and beginning to load the bags of herbicide.  Soon the airboat roared off toward the southwest end of the lake, and the pontoon boat puttered sedately to the north.

Throughout the day, the boats followed their intended courses, going back and forth in adjacent lines like a farmer tilling his field.  Each boat had a driver and one crew.  The drivers looked down most of the time, following the planned track on their GPS’s. Their helpers kept an eye outside the boat, and filled the hoppers with chemical from time to time.  Periodically they would return to one of the staging areas, where others loaded another half ton of chemical, in 40 pound bags.

We applied Renovate to about 130 acres of the lake, which is 450 acres in all.  The planned concentration was to be between 1.5 and 2.0 parts of herbicide per million parts of water.  Click on the map above right to see just where.

There were a few hiccups during the day, as can be expected.  The battery on one of the boats died, and a spreader became clogged.  A second airboat was put in service, and the spreader repaired. The pontoon boat was converted from liquid spreader to dry and back again.  Will Stevens of Lycott adjusted his game plan to meet changing conditions.  By 6:30 this evening the job was complete and the crew began packing up to go home.

~ ~ ~ ~ ~ ~ ~ ~ ~ ~

Setting up - preparing the HERD spreader on the front of the airboat

Some of the Renovate was dispersed using a machine that looks a lot like a lawn fertilizer spreader.  A rotating disk below a hopper of dry chemical flings a wide swath from the front of the airboat.

Loading the airboat in the morning fog

The Renovate was delivered in 40 lb. bags.  They were carried out on the dock and loaded by hand into the boats.  That is Will Stevens, the owner of Lycott, carrying the clipboard.

The airboat working near Middlebrook

Each boat had a crew of two.  Here the crewman prepares to pour another bag of herbicide into the hopper on the front of the boat.

The airboat coming back empty

The airboat has a Chevy V-8 with no muffler.  It makes an incredible amount of noise, but can really move across the water when it is not spreading.

The pontoon boat spreads the chemical in a liquid suspension

The dry chemical can also be dispersed mixed with water, with a device called an eductor.  This pumps a stream of lakewater through a venturi where it draws in the herbicide and the mixture is sprayed through two nozzles on the stern.  You can see the crewman replenishing the herbicide in the hopper.

The eductor at work

Here you can see the herbicide suspension spraying of the back of the boat.  Note the driver concentrating on his GPS.

~ ~ ~ ~ ~ ~ ~ ~ ~ ~

Our big day is over.   In 2 or 3 days the tops of the milfoil should begin showing distress.  In 4 to 6 weeks the milfoil should be visibly lying down.  We will conduct our first test of the concentration of the triclopyr 24 hours after the treatment, late on June 3rd.  The lake will reopen for swimming and recreation on Friday the 4th.  Now we wait.

Chemcal Treatment Permit Issued

Wednesday, May 26th, 2010

Today the Vermont Department of Environmental Conservation issued a permit which will allow us to treat the milfoil in Lake Fairlee with the herbicide triclopyr.  On initial reading the permit, which runs to 41 pages, appears to grant us substantially what we asked for.  As expected, it contemplates a five year program of milfoil control, which will involve mechanical as well as chemical methods.  We are authorized to conduct one spot/partial-lake treatment this year of up to 130 acres total.  This is slightly greater than the 120 acres that were identified in the survey conducted near the end of last season.

We are planning to treat the lake on Wednesday, June 2nd, beginning around 7:30am.  The application will be completed in one day, and the lake will be closed to all uses (including swimming, boating, fishing, etc.) for that day and the next. On Friday, June 4th, the lake will again be safe for these activities, and for domestic uses other than drinking and cooking. We expect that the lake water will be safe for cooking and drinking uses within about two weeks. We will be sampling the water for chemical testing regularly, as well as monitoring the milfoil, and will post the results here. Because the chemical we are using is toxic to grasses (and relatively benign for animals and other plants) it will not be safe to irrigate with lake water for most of the summer.

Here is the full text of the permit. LINK Happy reading.

No permit yet, but planning for June 2nd.

Friday, May 21st, 2010

We have recently learned that “the earliest that our permit could be signed is Monday” (May 24th) given the travel schedules of the people involved.

On the other hand, we have been encouraged to proceed with our planning.  The requisite chemicals have been ordered, and the warning signs will be printed, and we still expect to treat the lake beginning early on the morning of Wednesday June 2nd.  Hopefully the permit will be issued soon, and we will be given permission to do the treatment for which we have all planned.

Questions about well water

One downstream abutter expressed concern that the triclopyr we put in the lake could find its way into his well water. At our informational meetings last summer and fall we were reassured by the DEC scientists that contamination of well water is not an issue. We have asked for further authority in support of this.  Meanwhile, we offer this explanation from an informed LFA member:

If his well was properly installed  the casing should be driven into the bedrock. Water filtering through the rock to the base of the well could, conceivably be a decade after first falling on the surface. Moreover, it is a misconception to believe that just because you are located near the lake that the lake is feeding your well. The water at the bottom of our wells around here could, indeed probably, comes through sub-strata totally unrelated to the lake which, in the grand scheme of things, is but a temporary, glacially induced puddle resting, almost ephemerally, on top of a massive granitic and sandstone formation. In all the literature I have seen so far about tryclophyr none has mentioned the contamination of local wells or drinking water. If the tryclophyr could hang on for as long as it would take to reach the bottom of the well, the evidence is that at the concentrations that would filter through it might not be measurable.

Please check back to this blog for further news.

We still don’t have the permit, but . . .

Monday, May 17th, 2010

The Department of Environmental Conservation has not yet issued a permit for our lake’s herbicide treatment.  We are still planning to apply the chemical on June 2nd, and are moving quickly to complete the required notifications in time, trusting that the permit will indeed be granted.

Our situation is very frustrating.  We scurried and scrambled to complete the lengthy  application by the end of November last year. The application clearly indicated a treatment date in late May or early June.  We explained that an early date was required to accommodate the lifeguard trainings at the summer camps.  The State has had six months to act on our application.  Now we again have to rush to print and mail 120 certified return/receipt notification letters. We do not know what factors are complicit in the State’s late action, but we are convinced that the process could be improved.

The notification letters were all mailed this afternoon.  They are substantially as indicated in our most recent post.  They were certified mail, with the return receipt option.  We will collect the proof of receipt (green postcards) and check them off against our list of property owners.  By Thursday, May 27th, we have to send the state (1) a list of those abutters who acknowledged receipt of the notice, whether by green postcard or by email, and (2) photographs demonstrating that we have affixed a copy of the notice to the property of every other abutter.

NOTE: We will send this same notice by email to those for whom we have email addresses, and ask that you indicate that you have received it by return email.  This will help us get an early start on checking your name off the list.

We are having the required signs made, and will install them around the lake as required on May 30th.  Notices will be posted then in the three Towns’ Offices, and at Treasure Island beach.  Chemical application will begin around 7:30am on Wednesday June 2nd, rain or shine.

Permit about to be issued!

Friday, May 14th, 2010

We had been told to expect action on our herbicide permit application by today, May 14th.  Although the permit has not yet been issued, the DEC has sent us some of the notification information so that we can get started.  The permit will require that notice be delivered to owners of property abutting the lake and its outflow.

The following is the letter as proposed by the DEC.  Some of the information is clearly incorrect, and will be changed, for example the reference to Aquatic Control Technologies as the consultant/contractor rather than Lycott Environmental, Inc.  There is reference, too, to a “spot/partial lake treatment” which is not what we applied for, and to “the third year of a five year plan” which is also incorrect.  Because the letters have to be mailed fifteen days before the date of the herbicide application, they have to be done by next Tuesday,  May 18th, so we can expect to have more answers very soon.

Details will be posted here as we get them.

~ ~ ~ ~ ~ ~ ~ ~ ~ ~

Informational Notice and Map

The Lake Fairlee Association anticipates receipt of an Aquatic Nuisance Control Permit to Treat Portions of Lake Fairlee with the Aquatic Herbicide, Renovate OTF.

The Target Date for the Treatment Is [June 2nd, we hope], 2010.

The Exact Date Will Be Posted On Signs around the Lake
& at the Fairlee, Thetford and West Fairlee Town Offices.

Lake Water Use Restrictions

  • There shall be NO USE of Lake Fairlee and the outlet stream downstream to it’s confluence with the Ompompanoos River FOR ANY PURPOSE, including boating, fishing, swimming, domestic (household) use or irrigation, on the day of and the entire day after the treatment,
  • Swimming/wading, boating, fishing and domestic use (except drinking or for food or drink preparation) may resume the beginning of the second day following treatment.
  • Use of water from Lake Fairlee or the outlet stream downstream to it’s confluence with the Ompompanoos River for drinking or for food or drink preparation shall not resume until water sample analyses reveal that the active ingredient in Renovate OTF (triclopyr) is at or below 75 parts per billion by laboratory analysis.
  • Use of water from Lake Fairlee or the outlet stream downstream to it’s confluence with the Ompompanoos River for irrigation, including use for watering lawns, trees, shrubs or plants, shall not resume for 120 days or until water sample analyses reveal that triclopyr is at or below 1.0 part per billion by laboratory analysis, whichever comes first.

Bottled Water will be provided, if requested, to any person restricted from using their domestic water supply for drinking or in the preparation of food or drink.  Submit requests to:  Tracy (Skip) Brown, PO Box 102, Fairlee, VT 05045 or (802) ???-????

IF A RESIDENCE OR COTTAGE IS RENTED at any time after the treatment and before December 31, 2010, the property owner is responsible for informing all tenants of the treatment and the water use restrictions.

Issuance of an Aquatic Nuisance Control Permit with conditions is anticipated from the Vermont Department of Environmental Conservation (DEC) authorizing a spot/partial-lake treatment of Lake Fairlee with the herbicide Renovate OTF (active ingredient triclopyr). This treatment is the third year of a five year plan developed by the Lake Fairlee Association, with assistance from its consultant/contractor, Aquatic Control Technology, Inc. and approved by the DEC. The plan includes monitoring/surveillance of milfoil, hand pulling, suction harvesting and public education as well as partial/spot treatment with herbicide.

This notice serves to inform you that Lake Fairlee will be chemically treated with the USEPA and VT Dept. of Agriculture registered aquatic herbicide Renovate OTF (active ingredient triclopyr).  The target date for the treatment is [June 2, we hope] 2010, commencing at approximately 9AM. The exact date will be posted on signs around Lake Fairlee and at the Fairlee, Thetford and West Fairlee Town Offices. A map showing the treatment areas is attached. Please note the water use restrictions listed on the reverse apply to all of Lake Fairlee and to the outlet stream downstream to it’s confluence with the Ompompanoos River.

Prior to treatment, signs providing the date of treatment, warning of the water use restrictions and including a map of the treated and affected areas will be posted along the roadways in the vicinity of the Lake shoreline and the Outlet area affected by the treatment. Signs will also be posted at the Fairlee, Thetford and West Fairlee Town Offices and at access points where the public might enter or use the treated or affected areas.

The exact duration of the restrictions on using lake water for irrigation and for drinking and preparation of food and drink listed on the first page of this Notice is unknown but expected to be similar to last year. Water samples will be tested at intervals after the treatment to help determine when restrictions will be lifted.  Test results will be posted at the Fairlee, Thetford and West Fairlee Town Offices.  Do not act on these test results to make decisions about water use restrictions.  Restrictions will only be lifted by the DEC. Therefore, you must refer to the posted signs for information on the actual date that the water use restrictions will be lifted.

Please return the enclosed postcard to confirm you have received this notice. Your prompt reply will avoid the time and expense of an additional mailing or posting.  Thank you.

For Information:

Permittee                                       Co-Permittee
Lake Fairlee Association             Lycott Environmental Inc.
c/o Skip Brown                             Robert Wheaton
PO Box 102                                    600 Charlton Street
Fairlee, VT 05045                        Southbridge, MA 01550
802-33-4541                                 508-765-0101