Wellhead Protection Plan Keeping Public Water Safe

Transcription

Wellhead Protection Plan Keeping Public Water Safe
 Institute of Ag Professionals
Proceedings of the
2005 Crop Pest Management Shortcourse
www.extension.umn.edu/AgProfessionals
Do not reproduce or redistribute without the written consent of author(s).
WELLHEAD PROTECTION:
“Keeping Public Water Safe”
Brian Williams
Minnesota Department of
Agriculture
507-665-6806
What is Wellhead Protection?
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IT’S ALL ABOUT
PREVENTION !
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Preventing contaminants that
can adversely affect human
health from entering a public
water supply and the aquifer
supplying water to the well(s)
WELLHEAD PROTECTION
A HISTORIC PERSPECTIVE
JAMESTOWN’S SOURCE WATER PROTECTION PROGRAM
THE PROCLAMATION
“There shall be no man or woman dare to wash any unclean
linen, wash clothes...nor rinse or make clean any kettle, pot
or pan, or any suchlike vessel within twenty feet of the old
well or new pump. Nor shall anyone aforesaid within less
than a quarter mile of the fort, dare to do the necessities of
nature, since by these unmanly, slothful, and loathsome
immodesties, the whole fort may be choked and poisoned.”
Governor Gage
1610
Why emphasize prevention?
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More effective and cost-efficient than cleanup, treatment or drilling a new well
– Currently 6 public water suppliers with nitrate
removal systems—expensive alternative
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Large community investment in public water
supply system
Protect public health from short-term or longterm effects from consuming contaminated
drinking water
Wellhead Protection (WHP) History:
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Mn. Dept. of Health—Source Water Protection Unit
administers Wellhead Protection Program
1986 Federal Safe Drinking Water Act (SDWA):
Amendments
– required States to develop WHP Program & Processes
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1996 Federal SDWA: Additional Amendments
– Identify Source Water Protection Areas
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1989 MN Groundwater Protection Act: Framework for
protection efforts, rules.
1997 MN WHP Rule Approved—requiring public
water suppliers to develop plans
MDA’s Role
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Work with the MN Dept. of Health
– Provide technical assistance to public water
suppliers where agricultural land use activities
influence water quality
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The Minnesota Department of Agriculture
(MDA) is the lead state agency for all aspects
of pesticide and fertilizer environmental and
regulatory functions. Mn. Stat. Ch. 18B & 18C
– A person may not store, handle, distribute, use, or
dispose of a fertilizer or pesticide in a manner that
that will cause unreasonable adverse effects on
the environment
Nitrogen Management Plan
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Minnesota Statute (1989). Chapter 326,
Article 6, Section 33, Subdivision, 2b gave
responsibility for the development of
recommendations on a nitrogen fertilizer
management plan for the prevention,
evaluation and mitigation of non-point source
occurrences of nitrogen fertilizer in waters of
the State.
The nitrogen fertilizer management plan must
include components promoting the
prevention, and developing appropriate
responses to, the detection of inorganic
nitrogen from fertilizer sources in ground or
surface water.
What is a public water supply
well?
zA
well that provides piped drinking
water for human use to 15 or more
service connections or to 25 or
more people for at least 60 days
per year
Public water supply wells include:
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Community water supply wells, (970)
Non-community non-transient wells (562)
– serve the same population on a regular
basis (schools, factories, hospitals, day
care centers)
Non-community transient wells (5978)
– serve a temporary or transient population
(churches, restaurants, parks,
campgrounds)
General Requirements of All Public
Water Suppliers
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200’ radius surrounding public water
supply
– Maintain isolation distances for
potential sources of contamination
– Monitor existing sources of
contamination that do not comply
– Implement protection measures for
potential contaminant sources
Components of a Wellhead
Protection Plan: Community &
Non-Community—Non Transient
z Appointing
a Wellhead Protection
Manager
z Appointing a Wellhead Protection
Planning group
z Determining the Wellhead Protection
Area WHPA (the area that will
contribute water to the well[s] in the
next ten years)
Wellhead Protection Area WHPA
Surface and subsurface area surrounding a
well that supplies water to the well
z Boundaries scientifically calculated
z
– Time of Travel—minimum of 10 years
– Flow Boundaries—geologic composition
– Daily Volume Pumped
– Groundwater Flow Field—direction & hydraulic
gradient
– Aquifer Transmissivity—ability of the aquifer to
yield water
Wellhead
Protection Area
(366 acres)
Drinking Water
Supply Management
Area (545 acres)
Components of a Wellhead Plan cont.
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Conducting an inventory of potential
contamination sources in the Wellhead
Protection Area
1.Transportation Corridors
2.Agricultural Land Uses
3.Commercial Land Uses
4.Residential Wells & Septics
5.Storm Water Run-off
6.Storage Tanks
7.Mining operations
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Develop map identifying potential sources
Components of a Wellhead Plan cont.
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Well vulnerability—An assessment of the
likelihood of contamination entering the well
based on:
– Unknown well construction
– Well water containing elevated nitrates,
pathogens, or other chemical compounds
– Well water containing traces of tritium
– Geological sensitivity
What does “vulnerability” mean
and how does it impact WHP
Plan development?
z Vulnerable: All land uses considered in the
development
(agriculture, turf, tanks, septics, wells, etc.)
z Moderately Vulnerable:
Other wells and tanks
z Nonvulnerable:
Only consider other wells
Vulnerable
Public
Water
Supply
Wells in
Minnesota
Photo courtesy
of MDH
Percent of
wells
exceeding 3
mg/L.
MDH County
Well Index
nitrate results
summarized by
agroecoregion.
Photo courtesy of Dr.
Dave Mulla
Components of a Wellhead Plan cont.
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Define strategies for managing potential
sources of contamination
– 10 year implementation time frame
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Develop a plan for an alternative water
supply in the event of contamination or
mechanical failure
(emergency plan)
Surface Drinking Water
Suppliers
How are they different from
groundwater systems?
Surface Water Based Community
Public Water Supply Systems
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Aurora (mine pit)
Beaver Bay L. Sup.)
Biwabik (mine pit)
Chisholm (mine pit)
Duluth (L. Sup.)
E. Grand Forks (Red Lake
River)
Ely (Burntside L.)
Eveleth (St. Mary’s L.)
Fairmont (Budd L.)
Fergus Falls (Otter Tail R.)
Grand Marais (L. Sup.)
Hoyt Lakes (Colby L.)
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Int’l Falls (Rainy R.)
Mankato (Blue Earth/Minn.
Rivers)
McKinley (mine Pit)
Minneapolis (Miss. R.)
Moorhead (Red River)
St. Cloud (Miss. R.)
St. Paul (Miss R.)
Silver Bay (L. Sup.)
Thief River Fls, (Red Lk. R)
Two Harbors (L Sup.)
Virginia (mine pit)
Source Water Assessments for Surface
Water Systems
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Source Water Assessments identify an “inner
emergency response area.”
– This areas reflects the time needed to receive
notification & shut down an intake to respond to an acute
health risk in the event of a spill or toxic release
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An “outer management area” is also delineated
– protects water users from long term or chronic health
effects related to contaminates at low levels in the
surface water.
All surface water systems are vulnerable!!!!!
7700 Square Miles
CITY OF MANKATO
Ranney Well 57’ Deep
76,500 Acres
36,500 Acres
GROUNDWATER UNDER
THE DIRECT INFLUENCE
OF SURFACE WATER
Source Water Assessments for Surface
Water Systems
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Only Source Water Assessments are required
by the Federal SDWA. Not protection plans.
Most surface water systems are developing
management plans to protect their water supply
and intakes to proactively protect and prevent
the need for additional “expensive” treatment
options.
St. Cloud, Minneapolis, and St. Paul have
obtained federal funds to complete a Source
Water Protection Plan for the Mississippi River.
(Little Falls to St. Anthony Falls)
What are some common
wellhead protection objectives?
Tools for implementation.
Common Wellhead Plan Objectives
“Promote voluntary adoption of Best Management Practices”
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Educational Activities & Demonstrations
Promote Nutrient Management Planning
Promote EQIP and other Conservation Practices
Promote Ag & Turf Best Management Practices
Other non-ag related activities
–
–
–
–
–
Well sealing
Septic systems
Storm Water Runoff
Storage Tanks
Mining Operations
Examples of WHP Actions Steps
z
Promoting alternative crops in most sensitive
areas.
– Perennial covers (CRP), alfalfa, sourghamsudangrass, small grains
– New varieties requiring less N—Altura potatoes
– Cover Crops—can absorb excess N
Nutrient/Manure management planning
z Irrigation--Low pressure & scheduling
z Nitrogen rate, timing, & stabilized N
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– Split application, side-dress, & fertigation
– Polymer coated urea & N-Serve
es
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Priority Concerns
Program
Program Sponsor
Interactive mapping program
z Ability
to view WHPA, DWSMA
boundaries on aerial map.
z Ability to view vulnerability & acres.
z Enable ag professionals, farmers &
others to identify land located within
sensitive areas.
Low
vulnerability
(586 acres)
High
vulnerability
(1639 acres)
Wellhead Protection
Case Studies
Edgerton—population 1050
– Elevated nitrate levels ≈22 ppm
z
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Installation of nitrate removal system in 2002
Construction costs of $368,000
– Shallow wells 21’ and 39’ depth
– Manure applications in close proximity to city wells
– Worked with farmer to change manure
applications in sensitive areas
– Converted 47 acres to CRP
– Nitrate levels dropped to ≈ 8 ppm raw water
Current Land Use in Edgerton DWSMA
Case Study:
St. Peter—population 10,358
Seven supply wells 130’ to 670’ deep
z Increasing nitrate levels in Jordan
aquifer
z City currently blends water from deeper
wells to meet drinking water standards
z Two tile drainage ditches drain to
course textured soils and infiltrate to
aquifer
z Protection area covers 4600 acres
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19
Fe 91
b
M -9 4
ay
Au -9 4
g
N o -9 4
v
J a - 94
n
A p - 95
rJ u 95
l
O -9 5
ct J a 95
n
A p - 96
rJ u 96
l
O -9 6
ct
J a - 96
nA p 97
rJ u 97
lO 97
ct J a 97
nJ u 98
n
M -9 8
ar
J u -9 9
n
Se -9 9
pD e 99
c
M -9 9
ar
J u -0 0
n
Se -0 0
p
D e - 00
c
M -0 0
ar
J u -0 1
nSe 0 1
p
D e - 01
c
M -0 1
ar
J u -0 2
nSe 0 2
p
D e - 02
c
M -0 2
ar
J u -0 3
nSe 0 3
p03
N itrate-N (m g /l)
Monthly Nitrate-Nitrogen Levels
City of St. Peter Drinking Water Wells
14
-2
Year
Well # 6 (Jordan)
Well # 9 (Jordan)
Jefferson (South Water Plant)
St. Julian (North Water Plant)
12
10
8
6
4
2
0
Supply
Wells
Infiltration
Pond
Tile Drainage
Ditches
St. Peter Case Study cont.
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N rates on large portion of protection area have
decreased 25 lbs. per acre past 2 years
Since 90’s ave. yields increased by ≈40-50 bu.
/acre Farmers haven’t increased nitrogen
applications significantly.
– 1996 MDA FANMAP Survey concluded farmers applying
on average 154#/ N (corn-soy rotation)
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Large dairy operation—increased alfalfa acres &
manure nutrient source.
City exploring upland treatment basins along with
storm water run-off—future developments
Case Study:
Perham—population 2559
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Five supply wells 95-120 feet deep
Deeper aquifers contain high levels of iron
Course textured soils
Irrigation
High nitrogen requiring crops-corn, potatoes,
edible beans
Nitrate levels sporadically reach safe drinking
water standards of 10 ppm
Protection area covers 11,500 acres
Perham Case Study cont.
z
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10 year private well monitoring program
Farming practice changes
–
–
–
–
Nutrient management planning
Altura potatoes—lower N requirement
Polymer coated urea v.s. multiple UAN app.
Cropping changes—alfalfa, sourgham
sudangrass, CRP
– City purchased land—converted grass cover
future development
z
Education & outreach
20.0
15.0
10.0
5.0
Sampling Dates
05
5\
3
\0
10
02
5\
0
\0
10
99
6\
97
9\
96
5\
94
9\
93
0.0
4\
N itrate-N Co n c.(m g /L)
Perham Voluntary Private well
Sampling 1993-2005
721 Samples
Nitrogen Suction Lysimeter Data near Perham
Potato 2000, Soy Beans 2001, Potato 2002, Alfalfa 2003, Alfalfa 2004
100.0
Linear (AVG.)
N itr a te N itr o g e n
P a r ts p e r M illio n
80.0
Soy Beans 2001 Altura
Potato 2002
60.0
40.0
20.0
0.0
Alfalfa 2003
Alfalfa 2004
Alfalfa 2005
Burbank
Potato
2000
5 /1
6
6 /2 /00
6 /0
8 /4 0
9 /2 /0 0
0 /0
5 /1 0
7 /25 /01
1 2 4 /01
/1 8
6 / 1 /0 1
9 /0
9 /4 2
5 /2 /0 2
0
6 /2 /03
6 /0
7 /3 3
1 0 1 /03
/2 4
6 /9/0 3
9 /1 /0 4
0 /0
4
6 /2
0 /0
8 /1 5
/0 5
-20.0
Sampling Dates
12
5/ /20
1 9 05
5/ /20
2 6 05
/2
6/ 0 0
2/ 5
2
6/ 00
9/ 5
6/ 2 0
16 05
6/ /20
2 3 05
6/ /20
3 0 05
/2
7/ 0 0
7/ 5
7/ 20
14 05
7/ /20
2 1 05
7/ /20
2 8 05
/2
8/ 0 0
4/ 5
8/ 200
11 5
8/ /20
1 8 05
8/ /20
2 5 05
/2
00
5
5/
Nitrate-N in Soil Solution (mg/L)
Nitrate Losses—Russet Burbank v.s.
Altura Potatoes Perham
40.0
35.0
30.0
25.0
20.0
15.0
10.0
5.0
0.0
Russet
Burbank
Altura
Community Water Suppliers Currently
Responding to Nitrate Problems
Park Rapids
Perham
Lincoln Pipestone
Rural Water System
Edgerton, Ellsworth,
Luverne, Adrian,
Fulda
Cold Spring
St. Peter
Hastings
City of Hastings Water Quality
Supply wells 300-400’ deep
z Well #3 Shut down summer of 2005
z
– Cyanizine (Bladex) levels exceeded safe
drinking water standards
– Nitrate levels neared safe drinking water
standards (10 ppm)
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4 test wells drilled in past 2 years
– 2 exceeded 10 ppm safe drinking water
standards—other 2 with elevated levels
City of Cold Spring Water Quality
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Well # 2 shut down sporadically due to high
nitrates
3 new wells drilled in late 90’s & early 00’s
– increasing nitrate levels—
– increased from 3 ppm to 6 ppm
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Very rapid recharge—Water moves 1/4 -1/2
mile per year in narrow bands
Increased pumping rate by city increases nitrate
concentration
Large number of individual septic systems in
recharge area
Agriculture Considerations
Knowledge of “where” WHP and Source
Water Protection Areas are
z Already working with producers—be
conscience of vulnerable protection areas.
z Willingness to promote & support a variety of
management tools and options
z Support Wellhead Protection efforts in your
community.
z
Agriculture Considerations
z
Wellhead Protection rely heavily on the
adoption and implementation of
“voluntary” BMP’s…..
z
Need Support & Involvement of
Agricultural Professionals……….
Thank-you
Brian Williams
507-665-6806
[email protected]
www.mda.state.mn.us/water/protection
Nutrient Management Initiative
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Eligible counties south-central N BMP area
Establish replicated strips comparing 2 rates of
nitrogen or phosphorus on farms
Enable farmers to compare current N & P
nutrient management practices to NRCS
nutrient guidelines
Provide educational information to assist
farmers with tailoring nutrient management
To assist NRCS in adjusting future nutrient
management guidance
Nutrient Management Initiative
No manure of alfalfa history for past 5 years
z Only high and very high testing
phosphorous fields are eligible
z Farmer must work with a Certified Crop
Adviser: demonstration set-up,
recommendations, recordkeeping, & harvest
z Preferably no course textured soils
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Nutrient Management Design
Corn-soybeans or corn-corn rotations
z Minimize variables—keep all cropping
practices identical except phosphorous or
nitrogen applications
z Field uniformity desired—soil variability
perpendicular to rows
z
Nutrient Management Design
Soil test prior to participation
z Two rates—replicated 3 times
z Nitrogen sites require 100-200’—check
with 0 N rate
z Strip size—minimum of 40’ wide by
minimum of 600’ long
z Harvest—1 combine swath per 40’
z Weigh wagon—future yield monitor??
z
Nitrogen Design
0 Rate Strip
100’-200’ X 1
swath width
NRCS Nutrient Guidelines
Normally Applied Application Rate
NRCS Nutrient Guidelines
Normally Applied Application Rate
NRCS Nutrient Guidelines
Normally Applied Application Rate
0 Rate Strip
100’-200’ X 1
swath width
Phosphorous Design
z
High testing phosphorus soils
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Soil test >16 ppm Bray &/or 12 ppm Olsen
Must keep N rate constant
NRCS Nutrient Guidelines
Normally Applied Application Rate
NRCS Nutrient Guidelines
Normally Applied Application Rate
NRCS Nutrient Guidelines
Normally Applied Application Rate
Data Submittal
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z
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Farmer works with CCA
Cropping information submitted by July 1st
– Farmer receives $200 & CCA receives
$200
Harvest information submitted by
December 1st
– Farmer receives $400 & CCA receives
$400
Data Review
z Farm
results used as a pool of data
z Farmers identity kept confidential
z Farm Business Management
review results and evaluate
economics
z Educational meetings to review
outcomes
Nutrient Management Initiative
Information
www.mda.state.mn.us/nmi
Program administered
through Rural Advantage
Fairmont, Minnesota
507-238-5449