WATER WELL CONSTRUCTION

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WATER WELL CONSTRUCTION

Statute: Part 127 – Water Supply and Sewer Systems Act 368, PA 1978, as corrected (Public Health Code) (MCLA 333.12701 – 12715) R 325.1601 – 325.1781 Part 1 – Well Construction Code Part 2 - Drilling Contractors' & Pump Installers' Registration Part 3 – Drilling Machines & Service Vehicles Part 4 - Dewatering Wells FIRST BECAME EFFECTIVE FEB. 14, 1967 LAST REVISION – EFFECTIVE APRIL 21, 1994 For open water supply wells - Apply Part 8, Act 399, PA 1976 notwithstanding Part 127, Public Health Code

U. S. Trade, Bureau of Census 1990 Detailed Housing Characteristics 1.12 million family unit wells in Michigan HIGHEST IN NATION!

PROPER WELL CONSTRUCTION MATERIALS SANITARY WELL COMPLETION PRACTICES TRAINED PROFESSIONAL WATER WELL CONTRACTORS COMPONENTS OF A SAFE & RELIABLE WATER WELL TARGET AQUIFER HAS AMPLE YIELD & SAFE WATER PROPER WATER SYSTEM MAINTENANCE SUFFICIENT SEPARATION FROM CONTAMINATION SOURCES ROUTINE MONITORING OF WATER QUALITY

DEFICIENT WELL HEAD (CRACKED WELL CAP OR OPEN VENT) OLD WELLS WITH CORRODED WELL CASING SHALLOW DEPTH (OR SHORT CASING IN BEDROCK) POOR CONSTRUCTION (UNSEALED ANNULUS OR DUG WELL) WELLS MOST VUNERABLE TO MICROBIAL CONTAMINATION FLOODING, BURIED WELL HEAD OR SUBMERGED IN WELL PIT SEWER LINE BREAK, SEWAGE OVERFLOW OR CROSS-CONNECTION TOO CLOSE TO SEPTIC SYSTEM, AGRIC. Spillover OR ABANDONED WELL

WATER WELL USE PUBLIC SUPPLY AGR. Water system INDUSTRIAL TEST WELL OTHER 2% HOUSEHOLD 98%

RADIUS OF INFLUENCE STATIC WATER LEVEL WATER TABLE DRAWDOWN CONE OF DEPRESSION PUMPING WATER LEVEL AQUIFER COMMON WATER WELL TERMS

Types of Water Wells DRILLED DRIVEN DUG

WATER WELL DESIGN Provide well that addresses issues of proprietor Obtain most elevated yield with insignificant drawdown (consistent w/aquifer abilities) Provide reasonable quality water (consumable and without turbidity for drinking water wells) Provide long administration life (25+ years) NEW: Minimize impacts on neighboring wells & aquatic situations

DRILLED WELLS Terminated in icy float (sand, rock) or bedrock Constructed with revolving, link apparatus, flying, empty bar or wood screw boring strategies 2 in. on the other hand bigger packaging (Domestic wells: 4 – 6 crawl width)

DRILLED WELLS Casing material: Steel or PVC plastic Installed by well penetrating temporary workers Much more normal than driven or burrowed wells Most are >50 ft. profound (avg. 125 ft.) MOST SANITARY WELL TYPE

WATER WELL DRILLING METHODS IN MICHIGAN LESS COMMON: MOST COMMON: CABLE TOOL 10% AUGER 2.5% ROTARY (Mud & Air) 84% JETTING 1% HOLLOW ROD 0.5% OTHER 2% EMERGING TECHNOLOGY DUAL TUBE ROTARY HORIZONTAL SONIC

Rotary Cable Tool

TABLE DRIVE ROTARY MUD HOSE MAST SWIVEL TABLE DRILL RODS MUD MIXER BENTONITE DRILLING FLUID DRILL BIT MUD PIT

TOP HEAD DRIVE ROTARY TOP HEAD DRIVE UNIT DERRICK OR MAST DRILLING MUD RETURN FLOW HOSE DRILL RODS

DRILLING RIG OPERATOR CHECKING DRILL CUTTINGS DRILLING FLUID EXITING BOREHOLE STRAINER DRILLING MUD TANK

DRILLER COMPLETING THE WATER WELL RECORD WATER WELL & PUMP RECORD DESCRIBES: WELL DEPTH CASING LENGTH GEOLOGIC MATERIALS PENETRATED STATIC WATER LEVEL PUMPING WATER LEVEL PUMPING RATE GROUTING MATERIALS WELL LOCATION PUMPING EQUIPMENT DRILLERS NAME DRILLING RIG OPERATOR

TYPICAL ROTARY WELL CONSTRUCTION SEQUENCE OVERSIZED BOREHOLE DRILLED 1 IDENTIFY AQUIFER 2 INSTALL CASING (& SCREEN) 3 YIELD TEST & WATER SAMPLING 6 WELL DEVELOPMENT 5 GROUT ANNULAR SPACE 4

Bentonite Drilling Fluid - Functions - REMOVAL OF DRILL CUTTINGS FROM BOREHOLE STABILIZE THE BOREHOLE COOL AND LUBRICATE DRILL BIT CONTROL FLUID LOSS TO GEOLOGIC FORMATIONS DROP DRILL CUTTINGS INTO MUD PIT FACILITATE COLLECTION OF GEOLOGIC DATA SUSPEND CUTTINGS WHEN DRILLING FLUID CIRCULATION STOPS

Temporary well top - introduced between well boring and pump connect

Sanitary well top (covering & self-depleting) Screened air vent on underside of well top Tight seal amongst top and packaging Electrical conductor Well packaging funnel

This bored well has a more seasoned style well top that does not seal firmly to the well packaging. Bugs and little creatures can enter the well and sully the drinking water. Tops of this outline are not worthy and ought to be supplanted.

DRILLED WELL COMPONENTS WELL CAP or SEAL BOREHOLE SCREENED WELL CASING GROUT PACKER SCREEN

DRILLED WELL COMPONENTS WELL CAP BEDROCK WELL BOREHOLE CASING GROUT OPEN HOLE IN BEDROCK AQUIFER NO CASING IN ROCK BOREHOLE

BOREHOLE MINIMUM 2 IN. Bigger THAN CASING IF GROUTING THRU CASING MINIMUM 2 7/8 IN. Bigger THAN CASING IF GROUTING WITH GROUT PIPE OUTSIDE CASING Vertical round exhausting to achieve aquifer (water bearing geologic material)

CASING Steel or plastic pipe introduced to keep borehole divider from falling Houses submersible pump or turbine bowls & drop pipe STANDARD LENGTHS STEEL 21 FT. PLASTIC 20 FT. Least 25 FT. Packaging LENGTH BELOW GRADE

WELL CAP or SEAL Mechanical gadget to counteract contaminants (counting creepy crawlies) from entering great packaging OVERLAPPING SEALED TIGHTLY TO CASING SCREENED AIR VENT TIGHT SEAL TO ELECTRICAL CONDUIT

Device that seals space between packaging & extended screen to keep sand out of well PACKER (Coupling with neoprene elastic spines)

Intake gadget to permit water to enter well and keep sand out Structural support of aquifer material Wire-wrapped screen most normal SCREEN

K - PACKER SCREEN BLANK WELL SCREEN

GROUT Impermeable bond or bentonite earth slurry put in annular space amongst borehole and packaging to: forestall well sullying keep up partition of aquifers protect artesian aquifers TOP VIEW CASING BOREHOLE

DOWNWARD LEAKAGE AROUND UNGROUTED CASING INFILTRATION FROM SURFACE CONTAMINANTS STATIC WATER LEVEL CONTAMINANT PLUME UNSEALED ANNULAR SPACE AROUND CASING DOWNWARD LEAKAGE UNCONFINED AQUIFER

UPWARD LEAKAGE AROUND UNGROUTED CASING (Artesian Condition) STATIC WATER LEVEL UNCONFINED AQUIFER CONFINING LAYER CONFINED AQUIFER UPWARD LEAKAGE

BENEFITS OF WELL GROUTING PREVENT CONTAMINANT MIGRATION FROM SURFACE (Keeps surface overflow from moving descending along well packaging) SEAL OFF POOR QUALITY AQUIFERS (Prevents blending of water from various aquifers) PRESERVE ARTESIAN AQUIFER PROPERTIES ADDED SEALING OF CASING JOINTS

WELL GROUTING MATERIALS TYPE COMPOSITION CHARACTERISTICS FLEXIBLE LOWER STRENGTH SEAL MAY SUBSIDE IN VADOSE ZONE MOST POPULAR DUE TO LOWER COST AND TARGETED MARKETING WASH-OUT UNDER ARTESIAN PRESSURE NO HEAT OF HYDRATION MORE WIDELY USED IN OIL FIELD THAN WATER WELLS HIGHER STRENGTH RIGID SEAL BEST CHOICE FOR BEDROCK WELLS & FLOWING WELLS HEAT OF HYDRATION & MICROANNULUS CONCERNS MORE PERMEABLE THAN NEAT CEMENT GROUT MORE DIFFICULT TO PUMP (ABRASIVE) GOOD CHOICE FOR LARGE DIAMETER WELLS BENTONITE SLURRY POWDERED BENTONITE & WATER GRANULAR BENTONITE, POLYMER & WATER NEAT CEMENT PORTLAND CEMENT & WATER CONCRETE GROUT PORTLAND CEMENT, SAND & WATER

GRANULAR BENTONITE POURED INTO MIX WATER PORTABLE GROUTING MACHINE (MIXER & PUMP) GROUT PIPE TO BOTTOM OF ANNULAR SPACE BENTONITE GROUT RETURN AT SURFACE (GELATIN – OATMEAL TEXTURE)

WELL GROUTING ROTARY VS. Link TOOL GROUT PIPE IN ANNULAR SPACE DRY GRANULAR BENTONITE POURED AROUND CASING WELL CASING IN OVERSIZED BOREHOLE GROUT FOLLOWS DRIVE SHOE AS CASING IS DRIVEN DEPTH OF GROUT TRAVEL IS UNCERTAIN LIMITED BY HIGH WATER TABLE GROUT PUMPED FROM BOTTOM

BEDROCK WELL DETAILS CASING PIPE SHALE TRAP OR SHALE PACKER GROUT PREVENTS GROUT SPILLAGE INTO BEDROCK BOREHOLE BETTER SEAL AT BEDROCK INTERFACE TOP OF BEDROCK BOREHOLE (SMALLER DIAMETER THAN CASING)

Groundwater Concerns in Karst Bedrock UNPLUGGED ABANDONED WELL SEWAGE SYSTEM AGRICULTURAL WASTE & RUNOFF SINKHOLE CONTAMINATED WATER SEEPS DOWNWARD THROUGH THIN SOIL LAYER INTO FRACTURES & CREVICES IN KARST BEDROCK SIGNIFICANT RAINFALL OVER SHALLOW CARBONATE BEDROCK CAN CAUSE: SURGE IN WATER LEVELS (Increases water driven weight) INCREASED SURFACE WATER-TO-GROUNDWATER INTERCHANGE FLUSHING OF TURBIDITY & ORGANIC MATTER INTO GROUNDWATER

PROPER WELL CONSTRUCTION IN KARST SURFACE GLACIAL DRIFT OVER BEDROCK CASING & GROUT EXTENDING THRU UPPER BEDROCK IF BEDROCK WITHIN 25 FT OF SURFACE: MINIMUM 25 FT OF CASING GROUTED WITH NEAT CEMENT – BENTONITE GROUT NOT PERMITTED TOP OF BEDROCK SEVERELY WEATHERED LIMESTONE BEDROCK FRACTURES & INTERCONNECTED SOLUTION CHANNELS SHALE UNCASED BOREHOLE IN BEDROCK LIMESTONE

POOR WELL CONSTRUCTION IN KARST SURFACE GLACIAL DRIFT OVER BEDROCK CASING & GROUT ONLY EXTEND INTO TOP OF BEDROCK EVEN THROUGH CASING & GROUTING EXTENDS 25 FT. SAFE WATER QUALITY CANNOT BE ASSURRED TOP OF BEDROCK SEVERELY WEATHERED LIMESTONE BEDROCK FRACTURES & INTERCONNECTED SOLUTION CHANNELS BECAUSE BOREHOLE BELOW CASING INTERCEPTS SHALLOW, FRACTURED BEDROCK… WELL IS VULNERABLE TO CONTAMINATION FROM SEPTIC SYSTEMS, LUSTs, AGRICULTURAL CHEMICALS & SURFACE WATER INFILTRATION SHALE SYMPTOMS – E.COLI OR SURFACE WATER INDICATORS PRESENT AND SUSCEPTIBLE TO TURBIDITY AFTER HEAVY RAINFALL UNCASED BOREHOLE IN BEDROCK LIMESTONE

WELL CASING DEPTH IN KARST GLACIAL DRIFT OVER BEDROCK SEVERELY WEATHERED LIMESTONE BEDROCK FRACTURE