The NStar herbicide program to clear vegetation under transmission lines has brought a hidden expense behind our power supply to the fore. Chemicals are being sprayed– literally– in our backyards, from Bourne to Falmouth to Eastham. Towns are scrambling to complete GIS mapping of drinking water supplies and sensitive habitat in areas under these public rights-of-way– but time is running out.

Mutterings of discontent about NStar’s herbicide program erupted into a roar loud enough to reach US Rep. Delahunt in late March. But will NStar listen?

Power lines and trees cohabit at the Salt Pond Areas nature preserve off the bikepath

A powerful year…

For those who have not been following developments with NStar since the story broke last year, here’s a quick recap of events:

• In 2004, NStar embarked on a program to treat vegetation under utility lines with a mixture of herbicides. They have been using herbicides since 1984, but switched from mowing to spraying in Falmouth at this point.
• The utility company has a 5-year management plan, which it updates annually with detail about where it plans to spray, hand-prune, or touch up. This “yearly operational plan” (or YOP) is sent to towns each year, giving them 45 days to make comments.
• In summer 2009, Eastham residents called for a ban on the spraying of herbicides. Lower Cape residents volunteer to cut the vegetation themselves. Hearings with NStar reps lead to a temporary moratorium on spraying.
• January 2010: the Cape Cod Commission seeks a Cape-wide moratorium on herbicide use on rights-of-way, pending further study and better mapping of drinking water supplies and sensitive habitat.
• March 2010: Almost every Cape town sends a letter to the Department of Agricultural Resources in support of the Commission’s moratorium.  (Sandwich and Bourne do not; Mashpee has a 1982 ban on herbicide use; and Provincetown does not have any rights of way used by NStar.)
• March 26, 2010:  DAR approves a 30-day extension of the public comment period on NStar’s YOP.
• March 30, 2010: US Representative Bill Delahunt calls on the head of EPA to get more involved in regulating herbicides used by public utilities under transmission lines.

Paying the piper

It strikes me as odd that residents, otherwise known as customers, pay NStar to supply electricity, but are virtually ignored when they question the methods the company uses to safeguard the transmission lines.

NStar’s stated reason for using herbicides is that they are more effective than mechanical methods to ensure vegetation doesn’t interfere with the power supply. Company representatives cite federal law and national security, conjuring up the spectre of the 2003 blackout that swept the Northeast (allegedly caused by a fallen tree branch in Ohio).

But what about the effects of herbicides, some of which have been shown to have serious, adverse health effects?

He said, she said

NStar says the chemicals have been approved for sensitive areas by the EPA. It’s true. But some of the studies they cite in their operational plan are from the 1970′s. Some of the references cited by the DAR (the agency responsible for oversight) come from Monsanto company memos.

Concerned residents and the anti-pesticide group GreenCAPE question these studies, which test the active ingredient, but not the carrier agents in each product.  Further, the studies do not evaluate the effects of pesticides sprayed in combination with each other and with surfacants and wind retardants. They charge that the chemicals were not studied on the Cape, which has unique sandy, clay-filled soil and plenty of sensitive habitat.

NStar also says that the amounts of herbicide they plan spray over a large area are so minute that they really do not warrant concern.  Members of the Falmouth Board of Health (who shall remain nameless) have said they routinely spray larger quantities on their own lawns.

It’s a shame that our cultural obsession with trim green lawns comes second to our concern for environmental well-being. If the market is king, even those who limit their use of chemicals are susceptible to choices their neighbors decide to make.  But on a municipal level, because pesticides are cheap, easy to use, and don’t kill birds the way DDT did, does it mean we have to use them?

Ignorance is not bliss

Most people tend to think that anything the government approves is safe, because they have spent the money to study it and have developed regulations to protect us. But that is not always the case, especially with wiley chemicals. Because the herbicides that NStar contractors use are approved for “sensitive areas,” they are not subject to the provisions of the Massachusetts Wetlands Protection Act or local by-laws.

According to law, herbicides may be sprayed up to 25 feet from croplands or pastures. They may be applied as close as 50 feet from wells, and up to 10 feet from standing surface water. Herbicides may not be sprayed within 100 feet of a wetland or a public water supply.

The 30-comment period extension  provides a window of opportunity to get informed on the chemicals NStar plans to spray. It certainly won’t allow time for them to be studied, but will help us understand if they need to be studied further before being sprayed near water supplies and sensitive habitat.

The breakdown

In 2009, a combination of herbicides, wind retardants, and surfacants were backpack-sprayed by certified applicators under contract from NStar in Falmouth. These chemicals may also have been sprayed in other town, in some combination. Here’s the breakdown, based on information from GreenCAPE and its sources.

• Krenite S (Fosamine Ammonium): This chemical has a low pesticide movement rating, and spends an average half-life of 8 days in the soil.

• Accord SP (Glyphosate): This chemical is better known in its consumer product form, Round-Up. It moves very slowly in the soil, with an average soil half-life of 47 days. It is known to break down in the presence of water and sunlight, so it is preferred for use near water. However, glyphosate and its breakdown products were found in 50% of samples taken from 23 rivers across the country, in a 2007 USGS study. This product, unlike Round-Up or Rodeo, is pure glyphosate, with surfacants added separately.
• Escort XP (Metsulfuron-methyl): This herbicide has a high soil movement rating, and spends and average of 30 days in the soil. An Oregon State University study found that its mobility increases its potential to contaminate groundwater.
• Arsenal (Imazapyr isopropylamine) : An EPA incident report found that a mix of imazapyr, diuron, and metsulfuron methyl applied to a fence row was capable of causing a fish kill in a pond 60 feet away and a bird kill 85 feet away.
• Garlon 4 (Triclopyr ester): A 1999 USGS study of 10 urban watersheds near Seattle found this chemical, which has a low movement rating and average soil half-life of 46 days, in 90% of the sampled sites.

An osprey nest and a transmission tower represent possibilities for nature and modern convenience to co-exist

Well, there you have it.  Should we trust the studies that have found these chemicals to be safe, or err on the side of caution? Might there be another way to tackle vegetation while ensuring an interrupted power supply?

As I pass by the Salt Ponds Areas bird sanctuary on my way to work, this image makes me wonder if we wouldn’t do better by leaving the trees and plants to the rabbits and birds.