3.3 Shoreline Setbacks, Site Management Areas & Chemigation (Pes 1000, 502.06)

3.3 Shoreline Setbacks, Site Management Areas & Chemigation (Pes 1000, 502.06)

Chapter Pes 1000 is titled Restrictions on the Use of Pesticides to Protect Ground and Surface Waters. It is short, and every sentence in it is testable.

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Pes 1001.01 - the 25-foot shoreline setback

No residential property owner, private applicator, or commercial applicator shall apply pesticides to ground, turf, or established vegetation within the following distances of the reference line of those waters not covered by RSA 483-B The Comprehensive Shoreland Protection Act: (a) Within 25 feet as it pertains to surface waters; and (b) Beyond 25 feet in such a manner or by such methods that would result in the presence of pesticides within 25 feet of the reference line of any surface waters.

Three things to notice.

First, who it binds. This is one of the few New Hampshire pesticide rules that reaches residential property owners, not just licensees. A homeowner spraying a lawn that runs to a brook is inside this rule.

Second, which waters. The 25-foot setback applies to surface waters not covered by RSA 483-B. Waters that are protected shorelands under RSA 483-B are governed by that act, whose waterfront buffer is the 50 feet nearest the reference line (RSA 483-B:9 V(a)(1)). So the practical picture is: 50-foot waterfront buffer under the Shoreland Water Quality Protection Act; 25-foot pesticide setback under Pes 1001 for everything else.

Third, paragraph (b) closes the drift loophole. Standing 30 feet back and spraying toward the water is still a violation, because the test is where the pesticide ends up, not where the applicator stood. That makes nozzle selection, boom height, and wind direction part of compliance, not just good practice.

Pes 1001.02 - the four exceptions

The 25-foot restriction does not apply to:

1. Pesticide applications inside structures, provided there is no soil contact or soil incorporation;
2. Termite control applications, provided the applicator holds a special permit issued under the Pes 502.04 procedures;
3. applications subject to prior Division approval through a special permit where distances from surface water are determined case by case; and
4. vegetation control along the embankments of sewage lagoons at wastewater treatment facilities.

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Pes 1002 - site management areas

When pesticides turn up in water, New Hampshire has a mechanism short of outright prohibition.

Pes 1002.01 defines a site management area as a pesticide use, handling, storage, or distribution area connected to a ground or surface water source where pesticides are detected and where all three conditions exist:

• there are activities controlled by RSA 430:28-50 and Pes 100-1100;
• the site has a history of use of the contaminant pesticide within the last 5 years by private applicators, commercial applicators, or other persons; and
• the Division has determined that supplementary restrictions beyond the label and beyond Pes 100-1100 are necessary to minimize or prevent further contamination.

Pes 1002.02 defines potentially responsible parties as the landowner or anyone applying, handling, storing, or distributing the detected pesticides in the connected area.

Pes 1002.03 sets the investigation trigger: detection of a pesticide in at least 2 samples taken at different times from a groundwater or surface water sampling point. Importantly, an area where pesticide use has produced contamination that violates state ambient groundwater quality standards is not designated a site management area - it is regulated under RSA 485:3 and Env-Wm 1403 instead.

Pes 1002.04 requires the Division to report findings on water quality, potential source areas, potential receptors, a summary of use and handling at each potentially responsible site, and a discussion of whether the contamination resulted from label-consistent use, misuse, or accident.

Pes 1002.05 establishes a six-member site management area committee: a division of public health representative who is also a Board member; a DES representative with a chemistry background who is also a Board member; a second DES representative; a USDA Natural Resources Conservation Service representative; the director of the Division of Pesticide Control; and the coordinator of the state pesticide management plan for the protection of groundwater.

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Pes 502.06 - chemigation

Chemigation is applying pesticide through an irrigation system. Because the system is physically connected to a water source, it is the single highest-risk point-source pathway in agriculture, and the rule is prescriptive.

General requirements

• No pesticide may be applied through an irrigation or chemigation system unless the system complies with Pes 502.06.
• The method must comply with the state plumbing code and Env-Ws 364 "Backflow Prevention".
• No pesticide may be injected in a manner inconsistent with label directions.
• Every system must be properly calibrated to apply at the labeled rate.
• Every component must be resistant to corrosion, puncture, and cracking, and every component that may contact pesticide or pesticide-bearing water must be chemically compatible with every pesticide used.

The four required anti-pollution devices

+------------------------------------------------------------------+
|  CHEMIGATION SAFETY TRAIN (Pes 502.06(f))                        |
+------------------------------------------------------------------+
|  1. BACKFLOW PREVENTER  between the water supply and the point    |
|     of chemical injection, per Env-Ws 364.04(e)                   |
|  2. AUTOMATIC LOW PRESSURE DRAIN on the bottom side and lowest    |
|     point of the irrigation line between the irrigation pump and  |
|     the water supply line check valve; level; not extending past  |
|     the inside bottom surface of the pipe; positioned so drained  |
|     liquid flows AWAY from any wellhead or surface water          |
|  3. INTERLOCK between the irrigation pump and the chemical        |
|     injection unit, so injection stops if the irrigation pump     |
|     stops                                                         |
|  4. CHECK VALVE on the chemical injection line, to stop water     |
|     flowing from the irrigation system back into the chemical     |
|     supply                                                        |
+------------------------------------------------------------------+

Chemigation container setbacks

Pesticide containers used to hold product for injection:

• may not be located within 400 feet of gravel packed public water supply wells or 250 feet of other public supply wells - the same distances as Pes 502.05; and
• must be located at least 75 feet horizontally from a private water supply well or the high water mark of surface water, unless the total amount of pesticide at the site is 5 gallons or less of liquid or 50 pounds or less of non-liquid and secondary containment is provided.

That secondary containment must be located so its outside edge is at least 10 feet from any water supply, including a wellhead or surface waters or tributaries used for public water supply; be constructed of materials compatible with the pesticide; and be capable of containing 110 percent of the volume of the pesticide container.

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Worked example

A greenhouse and field vegetable operation wants to inject a labeled fungicide through drip irrigation. The mixing station sits 60 feet from the farm's own drilled well and about 300 feet from a brook.

• The mixing station is within 75 feet of a private water supply well, so it violates Pes 502.06(f)(6) unless the total pesticide on site is held to 5 gallons of liquid or 50 pounds of dry and secondary containment is installed.
• That containment must sit at least 10 feet from the wellhead and hold 110 percent of the container volume.
• The system needs all four devices: backflow preventer upstream of injection, automatic low pressure drain draining away from the well, pump interlock, and injection line check valve.
• Mixing and loading are separately governed by Pes 805.01, which forbids mixing or loading within 75 feet of surface water or private wells - with the same 5-gallon/50-pound plus containment exemption for chemigation under Pes 805.02(a).
• If a state inspector later finds the fungicide in two well samples taken at different times, the farm could be investigated for designation as a site management area under Pes 1002.