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? z IT’S ALL ABOUT PREVENTION ! z 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? z More effective and cost-efficient than cleanup, treatment or drilling a new well – Currently 6 public water suppliers with nitrate removal systems—expensive alternative z z 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: z z 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 z 1996 Federal SDWA: Additional Amendments – Identify Source Water Protection Areas z z 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 z Work with the MN Dept. of Health – Provide technical assistance to public water suppliers where agricultural land use activities influence water quality z 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 z z 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: z z z 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 z 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. z 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 z Develop map identifying potential sources Components of a Wellhead Plan cont. z 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. z Define strategies for managing potential sources of contamination – 10 year implementation time frame z 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 z z z z z z z z z z z z 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.) z z z z z z z z z z z 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 z 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 z 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 z z z 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” z z z z z 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 z – Split application, side-dress, & fertigation – Polymer coated urea & N-Serve es r o f n o i t c c e r t i e u t S o o n s r b o i e t e P c R e t W d o a r g p e / r A h l te f l a o e w / . s t W u . p n e m . D e t . a t n s . a M ww d m . w 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 z 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 z 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. z z 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) z z 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 z z z z z z z 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 z 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) z 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 z z 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 z z z 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 z z z z z 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 z 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 z z 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 z z z 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