HomeMy WebLinkAboutAg Chemicals in Ground Water REPORT ON THE OCCURRENCE AND MOVEMENT
OF AGRICULTURAL CHEMICALS IN GROUNDWATER:
NORTH FORK OF SUFFOLK COUNTY
SUFFOLK COUNTY DEPARTMENT OF HEALTH SERVICES
DAVID HARRIS, M,D,, H,P,H,
COHHISSIONER
H, W, DAVIDS, P,E,
DIRECTOR, DIVISION OF ENVIRONMENTAL HEALTH
PREPARED BY:
BUREAU OF WATER RESOURCES
JOSEPH H. BAIER, P.E., CHIEF
SY F. ROBBINS, HYDROGEOLOGIST
AUGUST, 1982
RECEIVED
JUN 3 1987
~old Tm Olerk
II.
III.
IV.
Ve
VI.
VII.
VIII.
IX.
Table of Contents
Summary .
Introduction
Background
Hydrogeology A. General
B. North Fork Transect
C. Cutchogue and Mattituck Hot Spots .
Groundwater Hydrology A. General
B. North Fork Transect
C. Cutchogue and Mattituck Hot Spots
Chloride A. General
B. North Fork Transect
C. Cutchogue and Mattituck Hot Spots
Nitrate A. General
B. North Fork Transect
C. Cutchogue and Mattituck Hot Spots
Aldicarb A. General
B. North Fork Transect
C. Cutchogue and MattitUck
Hot Spots .
Dichloropropane A. General
B. North Fork Transect .
C. Cutchogue and Mattituck Hot Spots .
Monitoring Program
Findings, Conclusions, A. Findings
B. Conclusions
C. Recommendations
and Recommendations
Bibliography
Page
1
22
25
29
31
31
34
38
41
41
46
49
49
54
56
58
62
62
65
66
68
68
69
7O
i
List of Appendices
App. A - Water Quality Data Summary:
App. B - Water Quality Data Sununary:
App. C - Water Quality Data Summary:
App. D - Velocity Field Calculations:
North Fork Transect
Cutchogue Hot Spot
Mattituck Hot Spot
North Fork Transect
App. E - Agricultural Well Pumpage: North Fork Transect
App. F - Discussion of Chloride Data: North Fork Transect
App. G - Well Construction Data
App. H - SCDH$ Chemical Analysis Forms
2-1
3-1
3-2
3-3
3-4
3-5
3-6
3-7
3-8
4-1
4-2
4-3
4-4
5-1
5-2
5-3
5-4
6-1
6-2
6-3
6-4
List of Figures
East End Study Areas
Farmland: Riverhead and Southold Towns
Shallow Groundwater Monitoring Well Network:
East End .
Aldicarb Sampling Results: Town of Riverhead
Aldicarb Sampling Results: Town of Southold
Study Areas: North Fork
Well Locations: Cutchogue Hot Spot
Well Locations: Mattituck Hot Spot
Well Locations: North Fork Transect
Page
5
9
14
15
16
18
19
20
Geologic Cross Section and Salt-Water Interface:
North Fork . 24
Geologic Test Hole Locations: North Fork Transect 26
Hydrogeologic Cross Section: North Fork Transect 27
Geologic Cross Section: North Fork Transect Area 28
Water Table and Groundwater Flow Directions:
North Fork . 32
Groundwater Flow Pattern: North Fork Transect 33
Groundwater Flow Pattern: Cutchogue Hot Spot 35
Groundwater Flow Pattern: Mattituck Hot Spot 37
Chloride: North Fork 40
Chloride: North Fork Transect 42
Chloride: Cutchogue Hot Spot 43
Chloride: Mattituck Hot Spot ...... 44
ii
7-1
7-2
7-3
7-4
8-1
8-2
8-3
9-1
9-2
D-1
E-1
F-1
List of Figures (cont'd)
Nitrate: North Fork 48
Nitrate: North Fork Transect 50
Nitrate: Cutchogue Hot Spot . 51
Nitrate: Mattituck Hot Spot . 53
Aldicarb: North Fork Transect . 57
Aldicarb: Cutchogue Hot Spot 59
Aldicarb: Mattituck Hot Spot 61
Dichloropropane: North Fork Transect
Dichloropropane Treated Fields: North Fork
Transect
63
64
Groundwater Flow Paths: North Fork Transect . D-5
Agricultural Wells: North Fork Transect E-2
Chloride Concentrations: North Fork Transect F-2
3-1
4-1
6-1
7-1
D-1
D-2
D-3
D-4
List of Tables
Aldicarb Survey Results: North Fork
Major Hydrogeologic Units: North Fork
Chloride Concentrations: North Fork
Nitrate Concentrations: North Fork
12
23
39
47
Head Measurements: North Fork Transect D-4
Vertical Velocities: North Fork Transect D-6
Horizontal Velocities: North Fork Transect D-6
Approximate Residence Times: North Fork Transect. D-8
LIRPB -
mg/1 -
MSL -
NYSDOH -
ppb -
ppm -
SCDEC -
SCDHS -
USDA -
USEPA -
USGS -
USPHS -
List of Abbreviations
fire well
Long Island Regional Planning Board
milligrams per liter
mean sea level
New York State Department of Health
parts per billion
parts per million
Suffolk County Department of Environmental. Control
Suffolk County Department of Health Services
United States Department of Agriculture
United States Environmental Protection Agency
United States Geological Survey
United States Public Health Service
iii
I. Summary
Since 1979, over 1,400 private wells in the Towns of
Southold and Riverhead have been found to be contaminated with
the insecticide aldicarb. Other wells have been found to con-
tain the agricultural fertilizer nitrate and the insecticide
dichloropropane. In response to this problem, the Suffolk
County Department of Health Services, under contract to the
New York State Health Department, drilled a series of geologic
test holes and monitoring wells along a north-south transect
near Cutchogue, and at two aldicarb "hot spots" in East
Cutchogue and Mattituck. The objectives of this study were
to assess the movement of aldicarb, nitrate, and dichloro-
propane within the North Fork's shallow groundwater aquifer,
and to identify the hydrogeologic processes that affect their
movement.
The analysis of data collected during this and previous
studies on the North Fork indicates that:
1) The amount of fresh groundwater available east of
Mattituck is limited by the presence of salty groundwater at
the coastlines and a thick clay layer only 100 ft. (or less)
below the water table.
2) The residence times of recharged precipitation within
the groundwater aquifer increase with increasing distance
from shore; near the center of the North Fork, residence times
approach 150 years.
3) The conservative agricultural chemicals nitrate and
(potassium) chloride, wkich have been in long-term use, are
pervasive within the aquifer below and downgradient of farm
fields.
4) Aldicarb contamination is presently limited to the
upper 30-40 ft. of aquifer except in the central recharge por-
tion of the North Fork, where it has been detected near the
bottom of the aquifer (100 ft. below the water table).
5) The pumping of agricultural irrigation wells has
probably accelerated the downward movement of nitrate and di-
chloropropane contamination.
These findings imply that:
1) Aldicarb, if conservative in groundwater, will even-
tually contaminate most of the North Fork aquifer, even though
additional inputs have ceased; concentrations will probably
approach or exceed the 7 ppb drinking water guideline.
2) If the above is true, it will take over 100 years for
the groundwater system to purge itself of aldicarb, and recourse
to deeper private wells to avoid aldicarb contamination will be
only a temporary solution to water supply problems.
3) If aldicarb is not conservative, as preliminary bench
tests performed by Union Carbide indicate, the material may
hydrolyze before reaching the deeper portions of the aquifer.
Based on these findings and conclusions, it is recommended
that:
l) Surveillance of private wells should continue in order
to protect the consumer and to track pollution in the upper
- 2
portions of the aquifer; sample analysis should be expanded to
include other agricultural chemicals.
2) A surveillance network that includes agricultural
wells and deep monitoring wells should be established to
monitor contaminant movement in the deeper portions of the
aquifer, and a sampling program at farm fields should be con-
ducted to determine the soil storage, leaching rate, and
degradation rate of aldicarb.
3) Planning and engineering studies should continue in
order to reduce future contaminant loadings and to find viable
alternatives for supplying North Fork residents with safe
drinking water.
- 3
II. Introduction
The residents of Suffolk County's North Fork rely solely
on groundwater for their supply of drinking water (Figure 2-1).
In recent years there has been increasing concern about the
contamination of this resource by agricultural chemicals (fer-
tilizers, insecticides, herbicides, fungicides). This concern
has led to the establishment of an observation well network by
SCDHS to obtain general water quality data, and a massive
sampling program by SCDHS and Union Carbide to identify com-
munity and private wells contaminated with the pesticide aldicarb.
The NYSDOH and SCDHS entered into a contractual agreement
in April, 1981 to obtain detailed water quality information at
selected locations on the East End, including three on the
North Fork (Figure 2-1). The objective was to more precisely
identify the overall horizontal and vertical distribution of
aldicarb, nitrate, and dichloropropane, and to assess the hydro-
geologic processes that control groundwater movement and may
affect the quality of the groundwater resource in the future.
This report presents the data collected on the North Fork
of Suffolk County by the SCDHS under the NYSDOH contract which,
along with data from previous studies and ongoing monitoring
programs, are used to evaluate the general hydrogeologic and
water quality situation. Groundwater management implications
are then assessed.
- 4 -
- 5 -
The major findings, conclusions, and recommendations of
the study are presented in Section I; a general description of
the problem and the methods used to address it are presented
in Section III, "Background." Sections IV and V describe the
geologic factors affecting the North Fork's groundwater resource,
and the directions and rates of groundwater flow; Sections VI
through IX present an analysis of data collected during the
study on chloride, nitrate, aldicarb, and dichloropropane,
respectively. A discussion of monitoring needs is presented
in Section X.
- 6 -
III. Background
Agriculture has been a major industry on the North Fork for
over 200 years. Although much farmland has been lost to develop-
ment in recent years, the Towns of Riverhead and Southold still
have over 26,000 acres under cultivation, which represents over
36 percent of their combined land area (Figure 3-1). Various
crops have been grown on the East End, but potatoes have tradi-
tionally been the major cash crop, with about 24,000 acres under
cultivation county-wide in 1979 (Pacenka and Porter, 1981).
North Fork soils are particularly well suited to potato culti-
vation, and with the addition of fertilizers such as nitrate
and potassium, produce large yields.
The practice of fertilization began in the early nineteenth
century, when fish were incorporated into the soil; manure was
also used, and by the 1870s, commercially prepared fertilizers
became available (Talmage, 1977). In 1929, a survey of Long
Island potato farms conducted by Cornell University found that
the annual average rate of commercial fertilizer application
to potato fields was 100 pounds of nitrogen per acre; over half
the farmers surveyed were also applying manure at an average
rate of 7.7 tons per acre per year as an additional nitrogen
source (Underwood, 1933). These fertilization practices led
to widespread nitrate contamination of the North Fork's shallow
groundwater aquifer, and prompted the establishment of a SCDHS
shallow monitoring well network to track the spread of nitrate
pollution (Figure 3-2).
- 7 -
J
z
- 9 -
The potato plant is susceptible to a number of pests, most
notably the golden nematode, which attacks the roots, and the
Colorado potato beetle, which eats the leaves. Since the early
1950s, pesticides containing 1,2 dichloropropane have been ap-
plied to fields infested with golden nematodes, particularly
those fields quarantined by the USDA. In 1974, the carbamate
pesticide aldicarb (trademark TEMIK, Union Carbide Corp.) was
registered for use on potatoes, and the USEPA accepted an
application rate of 3 pounds of active aldicarb per acre to
control the potato beetle (Guerrera, 1981). Aldicarb was to
be applied at the time of planting with the seed, where it
would be taken up by the roots and distributed throughout the
plant; it would then act as a systemic poison when the plant
is eaten by the beetles. Studies at the time of registration
(1974) implied that aldicarb would break down in the soil and
would not leach to groundwater.
In 1975, New York state approved the use of
five pounds per acre for control of the golden
nematode. In 1977, USEPA amended the aldicarb
federal label to allow the use of five pounds
per acre in Long Island, N.Y., only. In June
1978, New York state approved the use of post-
emergence side-dress application of two pounds
of active aldicarb per acre in addition to the
five pounds applied at planting. The USEPA
countermanded New York state's recommendation
until it was conclusively shown that aldicarb
residues in potatoes were less than the
established Food and Drug Administration tol-
erance of 1 mg/L (ppm). These data were
procured in 1978, and New York state rein-
stituted the postemergence side-dress
application in May 1979. (Guerrera, 1981).
- 10 -
Aldicarb was used by a large number of North Fork potato
farmers in 1975, and was almost universally used in the next
few years. Concerns about the leaching potential of aldicarb
were expressed by the Cooperative Extensive Service as early
as mid-1976, but no analyses were performed on groundwater
samples until August, 1979. At that time, the manufacturer,
Union Carbide, which alone had the laboratory capability for
detecting aldicarb, informed the USEPA that analyses of shallow
well samples located within potato fields were contaminated
with aldicarb's toxic breakdown products
and aldicarb sulfone.
Between August, 1979 and mid-March,
aldicarb sulfoxide
1980, the Suffolk
County Department of Health Services collected approximately
270 samples from shallow wells in areas near potato farms;
these were analyzed by Union Carbide, and almost one-third
showed aldicarb contamination. At the same time (December,
1979) Commissioner Harris of the SCDHS requested that the state
reduce the allowable application rate, especially the rate at
time of planting. Just two months later (February, 1980),
Union Carbide asked the USEPA to revoke its approval of aldicarb
on Long Island; this was done almost immediately, and aldicarb
has been unavailable for use on Long Island since that time.
The SCDHS continued its surveillance efforts during 1980.
From April through June, nearly 8,000 private wells in potato
farming areas were sampled; again, Union Carbide provided the
laboratory support (Table 3-1). Of 2,161 wells sampled in the
- 11 -
TABLE 3-1
ALDICARB SURVEY RESULTS: NORTH FORK
Town of Riverhead
Community~ % of Wells None Detected <7 ppb
Aquebogue 261 167 (64%
Calverton 464 322 (69%
Jamesport 227 144 (64%
Laurel* 299 108 (36%
Manorville** 76 65 (86%]
Riverhead*** 604 451 (75%
Wading River 230 208 (90%
Total 2,161 1,465 (68%)
>7 ppb
44 (17%) 50 (19%)
85 (18%) 57 (12%)
23 (10%) 60 (26%)
63 (21%) 128 (43%)
10 (13%) 1 (1%)
102 (17%) 51 (8%)
18 (8%) 4 (2%)
345 (16%) 351 (16%)
Town of Sout/%old
Community
% of Wells
None Detected
Cutchogue 579 415 (72%
East Marion 153 145 (95%
Greenport 45 39 (87%
Mattituck 984 742 (75%
New Suffolk 125 97 (78%
Orient 335 290 (87%
Peconic 225 160 (71%
Southold 714 539 (76%1
Total 3,160 2,427 (76%)
<7 ppb >7 ppb
70 (12%) 94 (16%)
3 (2%) 5 (3%)
1 (2%) 5 (11%)
121 (12%) 121 (12%)
13 (10%) 15 (12%)
27 (8%) 18 (5%)
34 (15%) 31 (14%)
105 (15%) 70 (10%)
374 (12%) 359 (11%)
%Mailing address.
*Includes some residents of Southold Town.
**Includes portions of Brookhaven.
***Includes Northville.
From: J. Baier and D. Moran, 1981, pp. 19 and 21.
- 12
Town of Riverhead, 32 percent showed contamination by aldicarb,
with 16 percent exceeding the NYSDOH guideline of 7 ppb. In
Southold Township, 23 percent of the 3,160 wells sampled showed
aldicarb contamination, with i1 percent exceeding the NYSDOH
guideline. The 1980 survey found that, in general, the shal-
lower the well and the shorter the distance to a potato field,
the greater the concentration of aldicarb (Baier and Moran,
1981).
The current study is an outgrowth of these previous
efforts. In particular, the SCDHS and NYSDOH were interested
in improving their knowledge of how nitrate, aldicarb, and
other contaminants move through the North Fork's aquifer. This
required the collection of data in the vertical as well as
horizontal direction. The existing SCDHS monitoring network
(Figure 3-2) was designed to measure the spread of pollution
only near the top of the aquifer, and the data from private
well sampling did not provide sufficient vertical coverage,
nor were the screen depths indicated for private wells con-
sidered accurate. Therefore, a new series of geologic test
holes and observation wells were drilled for this study.
The study areas examined during the current program were
selected on the basis of the results of the 1980 aldicarb survey,
which were mapped by computer (see Figures 3-3 and 3-4). Two
"hot spot" areas near the shore were selected--Cutchogue and
Mattituck (Figures 3-4 and 3-5). Monitoring wells at these
areas were drilled to a depth of 40-50 feet below the water
table at Cutchogue, and 40-70 feet below the water table at
- 13 -
O'lOH~,no$
C~'¢3H~3AI~
N3^'~H>IOOMI~
- 14
-/
- Z5 -
- 16 -
Mattituck; after a well was pumped and sampled, the casing and
screen were withdrawn at 10-foot intervals, where additional
samples were taken. In this way, a vertical profile of water
quality at each site was determined. The wells were generally
left in place at their last setting just below the water table
to provide water level information and follow-up water samples
(Figures 3-6 and 3-7).
In addition, wells were installed along a northwest-
southeast transect across the North Fork at Cutchogue (Figures
3-4, 3-5, and 3-8). This area was selected because it was
flanked on both sides 'by farm fields and provided easy access
to the drilling rig. Three geologic test holes were drilled
along the transect, and core samples were taken to determine the
local geology. Monitoring wells were installed in pairs; each
well was drilled to near the bottom of the aquifer, then one
well was withdrawn at 20-foot intervals and sampled to provide
a profile of water quality. The final settings, with one well
screened near the bottom of the aquifer and one well screened
near the water table, provided water level information with
which to determine vertical hydraulic gradients.
The chemical analysis of chloride and nitrate was performed
1
for the study by the SCDHS lab using an auto-analyzer. Analyses
of 1,2 dichloropropane and a whole suite of other organic contami-
nants were performed by the SCDHS lab using a gas chromatograph.2
1. Nitrite and ammonia were also measured, but are not used
in this report. Field conductivities and depth to water (DTW)
are also indicated on the lab forms (see Appendix H).
2. See Appendix H. Only 1,2 dichloropropane (#405) results
are used in this report. Test results for'other contaminants
were almost always negative.
- 17
FIG. 3-6 WELL LOCATIONS: CUTCHOGUE HOT SPOT
- 18 -
· '~.~. ' / Shore
Acre~
Watervill'e
7106
/
7108
..~ F W3
'-~'$3336
'",~'~ 7~o=1
U
FIG. 3-7 WELL LOCATIONS: MATTITUCK HOT SPOT
- 19 -
FIG. 3-8 NELL LOCATIONS: NORTH FORK TRANSECT
- 20 -
Aldicarb analyses were performed by H2M Corp. of Melville, N.Y.,
which reported results as total aldicarb (aldicarb + aldicarb
sulfoxide + aldicarb sulfone).
- 21 -
IV. Hydrogeology
HYDROGEOLOGY - GENERAL
A number of reports have previously been published that
describe the geology of the North Fork and its
to water resources (Woodward-Clyde Consultants,
Corp., 1978; H2M Corp., 1970; Crandell, 1963).
relationship
1977; H2M
They describe
the sequence of stratigraphic units on the North Fork, which
is similar to that found on the main body of Long Island
(Table 4-1).
A longitudinal cross section of the North Fork was de-
veloped during the p~esent study using well logs of test holes
drilled during previous studies (e.g., H2M Corp., 1970) and
geologic interpretations provided by the U.S. Geological Survey.
The contact between upper glacial aquifer and Magothy aquifer
deposits was found to vary in depth from about -200 to -430
feet MSL (Figure 4-1). Although a thick clay layer was found
at a depth of -65 to -85 feet MSL in each of the test holes, it
does not appear to form the contact between the two aquifers,
as the Gardiners clay does on the south shore of the main body
of Long Island. It is not certain whether the clays encountered
are all part of a continuous layer that underlies the entire
North Fork, or whether they occur as isolated lenses.
Fresh groundwater under the North Fork is believed to
exist as a series of four separate, irregularly shaped lenses
(Figure 4-1). The position of the freshwater-saltwater inter-
face, however, has only been measured in a few places (Figure 4-1).
- 22 -
- 24 -
Those measurements that are available indicate that the depth
of the interface is somewhat greater than would be predicted
by the Ghyben-Herzberg relation, which states that the inter-
face will be located 40 feet below sea level for each foot of
elevation of the water table above sea level (Figure 4-1).
B. HYDROGEOLOGY - NORTH FORK TRANSECT
Three geologic test holes were drilled
study along a northwest-southeast transect
for the NYSDOH
(Depot Lane) that
crosses the North Fork at Cutchogue, Town of Southold
$-71044,
and core
sand and
(wells
3
S-71170, and S-71279; Figure 4-2). Driller's logs
samples from these wells indicate a highly permeable
gravel formation that extends from land surface to a
depth of about -120 feet MSL (Figure 4-3). Beneath these
porous glacial deposits lies a clay layer that varies in thick-
ness from about 85 feet near the center of the fork, to about
200 feet, and possibly more, under the northern and southern
portions of the transect. Another sand and gravel layer, of
~nknown thickness, underlies the clay layer at the center of
the fork (see well S-71170, Figure 4-3). The stratigraphic
sequences of other test holes near the center of the fork show
a similar layering of clay and sand beds (see wells S-68831
and S-32390, Figures 4-2 and 4-4).4 The upper surface of the
3. The mud rotary method was used; a drag bit with an open
center was employed to facilitate the collection of core samples
with a split-barrel corer.
4. The apparent local dip of the beds, including the top
surface of the uppermost clay layer, is toward Depot Lane (see
Figure 4-4 and Appendix F).
- 25 -
H 0 L
'\
~ *,,~o,, ,=oo~o S~ 0 U T ~ H 0
FIG. 4-2 GEOLOGIC TEST HOLE LOCATIONS: NORTH FORK TRANSECT
- 26
v
DISTANCE FROM NORTH SHORE (1000 FT)
FIG. 4-3 HYDROGEOLOGIC CROSS SECTION: NORTH FORK TRANSECT
50-
-50 -
-200
-25(
-30(
~-~ CLAY, gray, with
~ c-~se sand and gravel
with grit a~nd gravel
SAND, fine to medium
brown, with grit and
small gravel
CLAY, solid and silty
brownish gray
CLAY, solid brown
brown, with grit,
gravel, some clay
No horizontal scale.
FIG. 4-4 GEOLOGIC CROSS SECTION: NORTH FORK TRANSECT AREA
- 28 -
clay layer in each of these test holes is found at an elevation
similar to that found throughout the region (compare Figures
4-1, 4-3, and 4-4).
Pore waters from core samples from the northern and
southern transect wells were analyzed for chloride; the results
indicated that the freshwater-saltwater interface occurs at
about -270 feet and -280 feet MSL, respectively (Figure 4-3).
These depths are much greater than would be predicted by the
Ghyben-Herzberg relation, and are probably due to the osmotic
effects of the low permeability clay.5 Cores from the center
well ($-71170) were not analyzed, but earlier tests from a
nearby well (S-32390) showed the interface to be at about -290
6
feet MSL (Figures 4-2 through 4-4). Thus, there may be some
fresh water below the clay layer (below -228 feet MSL) at well
$-71170, but the quantities would be extremely limited (if any)
and any attempts to pump this water would probably cause up-
coning of salt water from below as it did during tests at
well S-32390.7
C. HYDROGEOLOGY - CUTCHOGUE AND MATTITUCK HOT SPOTS
The deepest wells drilled at the Cutchogue and Mattituck
hot spots reached a depth of about -50 to -60 feet MSL.8
5. Although clay is very porous and holds a large volume
of water, its. low permeability makes this water unavailable
for water supply purposes.
6. H2M, 1970, Vol. II, p. 269.
7. Ibid.
8. These wells were drilled with a hollow-stem auger.
- 29 -
The driller's logs for these wells indicated that the shallow
subsurface geology consists almost entirely of sands deposited
as glacial outwash; a few thin (~1 foot thick) clay lenses were
also encountered just below the surface. No major confining
beds or other significant hydrogeologic features were discovered.
The freshwater-saltwater interface was found right at the shore-
line in both areas.
- 3O
V. Groundwater Hydrolo~
A. GROUNDWATER HYDROLOGY - GENERAL
The direction of groundwater flow on the North Fork can be
determined from maps of the water table (Figure 5-1). Ground-
water elevations are highest near the center of the fork (~4 ft.)
and lowest near the shorelihe. Flow is perpendicular to the
water-table elevation contour lines, moving outward from a cen-
tral groundwater divide toward either shoreline (Figure 5-1).
The rate of flow depends on the magnitude of the hydraulic
gradient (slope of the water table) and on the hydraulic con-
ductivity (permeability) of the material.
B. GROUNDWATER HYDROLOGY - NORTH FORK TRANSECT
Water-table elevations were measured at transect wells
during the five months October, 1981 to February, 1982 (see
Appendix D, Figure D-4). Water levels of 4-5 feet MSL were
found along the central groundwater divide. On either side
of the divide the water table slopes gently seaward; within
1,000 feet of the shoreline the water table starts to slope
more steeply, dropping from about 2 feet MSL to sea level it-
self right at the shoreline (Figure 5-2). Temporally, the
water levels increased from October to February, with the
greatest increases near the divide (~2 feet) and the smallest
increases near the shorelines (~½ foot).
- 31 -
- 32
- 33 -
Subsurface flow patterns for the transect were determined
using five-month average water-level values for each shallow
and deep well (Figure 5-2). Near the central groundwater divide,
flow was found to be vertical, with velocities of approximately
0.1 ft/day.9 The major portion of the transect was found to be
dominated by horizontal flow, with calculated velocities on the
order of .2 to .4 ft/day; some downward recharge also occurs in
these areas. Within 1/4 mile of the shorelines, the vertical
component of flow is upward as groundwater is influenced by the
boundary effects of the saltwater interface and is discharged
via seepage and underflow to surface waters.
The above results imply that water percolating through the
soil and reaching the water table near the center of the fork
will take 100 years or more to complete its movement through
the aquifer before being discharged to surface waters. Water
recharged to areas with shallow, horizontal flow will have
residence times ranging up to about 30 years (see Appendix D).
C. GROUNDWATER HYDROLOGY - CUTCHOGUE AND MATTITUCK HOT SPOTS
The direction of groundwater flow in the area of the
Cutchogue hot spot is determined by the slope of the water
table, which generally follows the slope of the land surface
down toward East Creek (Figure 5-3). Because of the sharp
drop-off of the water table in this area, horizontal flow
9. See Appendix D for a discussion of the groundwater
velocity calculations.
- 34 -
· Data po:Lnt (feet above mean sea leve~)
( ) Horizontal velocity (ft/day)
.I
2.7&;
.. I, ii-
:. i. I ' ' .I..!
' '1':!.!
II
East
Cutchogue
I I 1
I I
FIG.
5-3 GROUNDWATER FLOW PATTERN: CUTCXOGUE HOT SPOT
- 35 -
velocities are relatively higk (on the order of 1.0 to 1.5 ft/
day, see Figure 5-3).10 Clusters of wells at various depths
were installed only recently (February, 1982); thus, the records
of head (water level) measurements at these wells are not long
enough to calculate vertical velocities. It is expected that
vertical velocities will be fairly small, with a small downward
component near the surface of the water table (indicating local
recharge) and an upward gradient at depth (reflecting regional
flow patterns).
The direction of groundwater flow at the Mattituck hot
spot is influenced greatly by Long Creek, which extends north-
northeast from Mattituck Creek (see Figure 5-4). The slope of
the water table increases rapidly near the creek; flow is
11
primarily horizontal, with velocities ranging 1-2 ft/day.
10. This velocity was calculated for the area between the
2.0. foot water-table elevation contour at the farm field and
East Creek using the methodology outlined in Appendix D.
11. Paired wells (piezometers) were not installed at the
Mattituck hot spot, so vertical gradients could not be measured;
they are assumed to be small. Horizontal velocities were cal-
culated for the area between the 2.5 foot water-table contour
and the creek using the methodology outlined in Appendix D.
- 36 -
I)
$°71087
sd~?~oss
F.If. 8
('T)
I
I ,.v. ,
I
S-53336 ~.
(2)
1..-.-
3.0
2.5
I .I
i
( ) horizontal velocity (ft/day)
m mWater table elevations (average of monthly data 10/81-5/82).
Elevation dat~ is mean sea le~.
feet
5~o
l~OO
FIG. 5-4 GROUNDWATER FLOW PATTERN: MATTITUCK HOT SPOT
- 37 -
VI. Chloride
A. CHLORIDE - GENERAL
Although chloride contamination of groundwater is generally
not a public health concern, it was of interest in this study
because of chloride's extremely conservative nature in the
groundwater environment; it can thus provide insight into the
probable movement of other conservative chemicals applied to
farm fields. Chloride concentrations on the North Fork have
been examined in a number of previous reports (H2M Corp., 1974;
Woodward-Clyde Consultants, 1977). These studies and data from
SCDHS files on private wells indicate that chloride levels in
the upper glacial aquifer on the North Fork range from natural
background levels (less than 20 ppm) to over 250 ppm (Table 6-1,
Figure 6-1). Most of the values, however, are well below the
USPHS drinking water standard of 250 ppm (Table 6-1).
The sources of chloride contamination include rainwater,
agricultural fertilizers, cesspool leachate, and road runoff
(road salt). Chloride levels in rainwater generally average
less than 5 ppm; sea spray during severe storms may raise
chloride levels significantly. Agricultural chemicals, par-
ticularly potassium chloride, is probably the major source,
contaminating water at about 30 ppm.12 Cesspool leachate is
a minor source on the North Fork, as is saltwater intrusion
(both lateral and upward).
12. Potassium chloride applied at the normal rate of 286
lbs/acre/yr (150 lbs K/acre/yr) will produce an average con-
centration in recharge of 30 mg/liter, assuming a recharge rate
of 20 inches/year.
- 38 -
TABLE 6-1
+
CHLORIDE CONCENTRAIIONS: NORIH FORK
~,.~,,un.J.t'~. ! of ~11~ 0-10 10-20 20-100 100-250
J~juebogue 132 13 (10%) 45 (34%) 62 (47%) 6
Calv~'to~ 99 48 (48%) 27 (27%) 21 (21%) 3 (3%}
J~To. rt ?8 9 (12%) 28 (36%) 39 (50%) 0 (0%)
Manor~le* 121 86 (71%) 24 (20%) 11 (9%) 0 (0%)
~Lv~rb~** 254 96 (38%) 63 (25%) 91 (36%) 3 (1%)
W~n~ Ri%~-r 173 42'(24%} '96 (55%) 33 {19%} '2 (1%)
Total 857 294 (34%) 283 (33%) 257 (30%) 14 (2%).
To~n of 'Southold
{2c,~,,unlt~,~ # of Wells 0-10 10-20 200100 100-250
Cutchogue 227 4 (2%) 47 (21%) 162 (71%) 8 (4%)
East }~rion 69 3 (4%) 22 (32%) 38 (55%) 4 (6%)
Qreenport 74 3 (4%) 13 (18%) 53 (72%} 4 (5%)
Laure~ 49 2 (4%) 11 (22%) 31 (63%) 2 (4%)
Mattituck 287 17 (6%) 103 (36%) 160 (56%) 5 (2%)
New Suffolk 25 i (4%) S (20%) 17 (68%) 2 (8%)
O~ient ~8 3 (3%) 24 (24%) 66 (6?%) 3 (3%)
_Peo~___/c 46 2 (4%) 13 (28%) 26 (5?%) 5 (11%)
Southold 335 16 (5%) 96 (29%) 209 (62%.} 8 (2%)
~ 1,210 51 (4%) 334 (28%) 762 (63%) 41 (3%)
*Includes portions of F~ookha~.
**Includes Northville.
+Concentrations in ~. (rog/liter). Percentages are for the ~munity (~ow).
fr~n SCIT~S Drinking ~a~er ~pply Sectic~ files ¢~ private we_lls.
>250
C5%)
C0%)
(3%)
(0%)
(0%)
(0})
(1%)
>250
6 (3%)
2 (3%)
I (1%)
3 (6%)
.2 (1%)
0 (0%)
2 (2%)
0 (0%)
6 (2%)
22 (2%)
- 39 -
- 40 -
B. CHLORIDE - NORTH FORK TRANSECT
Chloride levels along the transect generally range from
20 ppm to 60 ppm, which is considerably higher than natural
levels (below 20 ppm) found in the upper glacial aquifer
(Figure 6-2). Significantly elevated chloride levels are
found throughout the aquifer.13 Elevated chloride levels
appear to have a good correlation with elevated nitrate values,
which implies that agricultural fertilizers are the major
source of chloride ions in the groundwater. It appears that
the entire upper aquifer has been impacted by the extensive
farming activity taking place above, and that agricultural
well pumpage may have accelerated the movement of contaminants
through the aquifer (see Appendix E). The data also suggest
that any widely used conservative agricultural chemical is
also likely to be found throughout the aquifer after some time.
C. CHLORIDE - CUTCHOGUE AND MATTITUCK HOT SPOTS
Chloride levels at the Cutchogue hot spot show the same
range of elevated values as is observed throughout the North
Fork (Figure 6-3). The entire area appears to be impacted,
including the groundwater at depth. The freshwater-saltwater
interface is shown to be located right adjacent to the shore-
line (Figure 6-3).
Chloride data for wells at the Mattituck hot spot are
presented in Figure 6-4. The two wells nearest the creek
(S-71087 and F.W. 9) show saltwater intrusion at shallow depth.
13. For a further discussion of chloride data, see
Appendix F.
- 41 -
7 7
(J,~) NO I J~'~/A~¥I~
0
0
42 -
- 43 -
10-19 2,100 -- 54 -- ~90 37 33 25 ....
50-59 X~O ........ 49 ........
FIO. 6-4 CHLORIDE: ~AIIIIUC[ HOI SPOT
- 44 -
Ail wells show elevated chloride levels; wells S-71088 and
S-71089 are highly contaminated, with levels up to 220 ppm.
The source of chloride in these upland wells is probably the
farm field located immediately upgradient.
- 45 -
VII. Nitrate
A. NITRATE - GENERAL
Nitrate levels on the North Fork are significantly elevated
from what are considered natural background levels (0.1-1.0 ppm,
see Table 7-1). Large areas are affected, and concentrations
often approach or exceed the USPHS and USEPA drinking water
standard of 10 ppm (10 mg/1, see Table 7-1 and Figure 7-1).
The extent and movement of nitrate in the upper portions
of the aquifer have been monitored by SCDHS with its monitoring
well network (see Figure 3-2). Data from these wells and pri-
vate wells were used to map impacted areas (Figure 7-1). The
severity of the problem is also reflected in a recent SCDHS
s~rvey of 600 private wells located within about 2,500 feet of
farmland, which found that about 25 percent exceeded the nitrate
standard.14
The primary source of nitrates to groundwater is agricul-
tural fertilizers. Nitrogen fertilizers applied to potato
fields at a typical rate of 200 lbs/acre/year will produce an
average concentration in recharged water of 16 ppm.15 Cesspool
leachate and lawn fertilizers may be more significant sources
in residential areas of the North Fork.
14. Dennis Moran, SCDH$ Drinking Water Supply Section,
personal communication 3/24/82.
15. This assumes a plant uptake rate of 125 lbs/acre/year,
and a recharge rate of 20 inches/year.
46 -
TABLE 7-1
NITRATE CONCENTRATIONS: NORTH FORK
C~.unit}, # of Wells 0-5 5-7.5 7.5-10 >10
A:ju~:x:~jue 11,6 54 (47%) 25 (22%) 15 (13%) 22 {19%)
Calvertcm 59 36 (61%) 8 (14%) 5 (8%) 10 (17%)
,.Tames~oort 76 51 (67%) 13 (17%) 4 (5%) 8 (11%)
Yanorville* 67 55 (82%) 2 (3%) 5 (7%) 5 (7%)
Ri..,~r~,-l** 179 88 (49%) 21 (12%) 27 (15%) 43 (24%)
~,,~ir~ River 142 88 (62%) 33 (23%) 9 (6%) 12 (8%)
Total 639 372 (58%) 102 (16%) 65 (10%) lO0 (16%)
·own of Soutbolcl
~'-,.,unity # of wells 0-5 5-7.5 7.5-10 >10
Cutchogue 210 92 (44%) 47 (22%) 33 (16%) 38 (18%)
~ast Mari~n 67 45 (67%) 12 (18%) 4 (6%) 6 (9%)
~ 72 44 (61%) 14 (19%) 7 (10%) 7 (10%)
Laurel 49 17 (35%) 12 (24%) 9 (18%) 11 (22%)
Mattituck 264 130 (49%) 46 (17%) 38 (14%) 50 (19%)
New Suffolk 25 18 (72%) 4 (16%) 3 (12%) 0 (0%)
Orient 98 52 (53%) 21 (21%) 7 (7%) 18 (18%)
Peccxtic 40 18 (45%) 9 (22%} 3 (8%) 10 (25%)
Sout~ld 296 159 (54%) 40 (14%) 45 (15%) 52 (18%)
Total 1,121 575 (51%) 205 (18%) 149 (13%) 192 (17%)
*Includes portions of B~okhave~.
**Includes Northville.
+Cor~entrations in p~ (mtTliter). t~rc~ntag~s ar~ for t/~ ~u,,,unity (~w). ~ata
taken from ~ Drinking Nater Supply S~=ctic~ files c~ private wells for which a
specific value is recorded. (Values reported as less than ~ nutS' ~_r are not
in=lu~d. )
- 47 -
B. NITRATE - NORTH FORK TRANSECT
The range of nitrate values along the transect is similar
to that found in other areas impacted by agricultural fertil-
izers (Figure 7-2). The entire transect is affected, including
groundwater at depth. There appears to be a good correlation
between nitrate levels and chloride levels, thus supporting the
conclusion that agricultural fertilizers are the primary source
(see Appendix A and Section VI. B). The fact that neither ni-
trate nor chloride concentrations decrease significantly with
16
depth implies that little dilution is taking place. This is
not surprising, since most of the land surface near the tran-
sect is covered by farm fields; thus, little uncontaminated
water is being recharged with which contaminated water can mix.
Also, the effects of longitudinal dispersion are made insig-
nificant by the long-term, continuous use of these fertilizers.
C. NITRATE - CUTCHOGUE AND MATTITUCK HOT SPOTS
The profile of nitrate levels for the Cutchogue hot spot
shows that most samples were near or exceeded the USPHS drink-
ing water standard of 10 ppm (Figure 7-3). Since this area is
one of shallow recharge and horizontal flow, elevated nitrate
levels at depth (i.e., below -30 ft. MSL) are probably due to
contamination originating further upgradient (to the north)
that is carried by regional flow patterns (which in this area
have an upward component). High nitrate values are also found
16. See also Figure 6-2. It also implies that both are
truly conservative (i.e., do not decay, react, absorb, or adsorb).
- 49 -
(J, cI)
- 50 -
o
o
o
0
- 51 -
within the zone of diffusion along the saltwater interface
(well S-71188, Figure 7-3).
Nitrate levels at the Mattituck hot spot are also sig-
nificantly alevated, even at depth (Figure 7-4). Again, this
probably represents the effects of agricultural pollution from
nearby fields being recharged from above, and pollution from
distant fields being carried upward by vertical regional flow
(discharge).
- 52 -
S.71088
F,V. l&
;-71090
S-71089
So71091
S-7]087
'F.V. 9
F.~. 8
I
i
40-49 7.3 -- 0.7 2.2 1.9 8.1 -- 9.7 ....
FIG. 7-4 NITRATE:
MATTITUCK HOT SPOT
- 53 -
VIII. Aldicarb
known is
the soil
material
1981).
A. ALDICARB - GENERAL
The estimated average application rate for aldicarb during
the years it was in use was about 5 lbs/acre/year. A small per-
centage (<20 percent) of the aldicarb applied to potato fields
is thought to be assimilated by the plant. The remainder is be-
lieved to leach downward through the soil column, where an
unknown percentage is decomposed by microbial action. Also un-
the percentage of aldicarb retained (adsorbed) within
column below the root zone, and how susceptible this
is to leaching at some future time (Pacenka and Porter,
These uncertainties make it difficult to estimate the per-
centage of aldicarb applied to a given field that will reach
the water table. INTERA Environmental Consultants, Inc., in
their 1980 report to the USEPA, were best able to reproduce
field-study data collected at Wickham Farm, Cutchogue, when a
value of 20 percent was used in their computer simulations
(INTERA, 1980). Using this 20-percent figure and a 5 lbs/acre/
year application rate, a simple mass balance predicts a re-
sultant concentration of 220 ppb at the water table below the
farm field; this concentration is very similar to those found
17
at Demarest Farm, Orient, during a SCDHS testing program.
17. The mass balance assumes that the leaching aldicarb is
uniformly mixed with 20 inches of rainfall recharge per year.
Demarest Farm data are from a Union Carbide memo (2/26/81) on
SCDHS samples collected under the Emergency Use Program (EUP).
- 54 -
The fate'of aldicarb within the aquifer (saturated zone)
is also largely unknown. In the INTERA study at Wickham Farm,
the best computer simulation fit of water quality data from
the saturated zone was achieved with an infinite half-life when
a 20-percent leaching rate to the water table was assumed
(INTERA, 1980).18 Recent laboratory studies by Union Carbide
on the hydrolysis of aldicarb indicated that the half-life of
aldicarb and its toxic breakdown products would probably be
only 2-3 years for Long Island groundwater conditions.19 To
date, no long-term field data records have been available with
which to determine trends in aldicarb concentrations. If the
Union Carbide estimate of a 2-3 year half-life is accurate,
however, it would take groundwater polluted at 220 ppb (see
above) from 10-15 years to reach the 7 ppb level (assuming no
biological degradation within the saturated zone). On the
other hand, if aldicarb proves to be conservative in ground-
water, no degradation will occur, and concentrations will be
reduced only slightly by mechanical dispersion as the ground-
water slowly moves through the aquifer.
18. A "half-life" is the time required for a substance to
degrade to a mass which is 50 percent of the original mass.
The "half-life" concept is usually associated with first-order
decay processes, in which the rate of decay at any time is
directly proportional to the amount left.
19. Unpublished data, Union Carbide. The half-life of
aldicarb, aldicarb sulfoxide, and aldicarb sulfone in sterile
water at various pH and temperature values were determined.
- 55 -
B. ALDICARB - NORTH FORK TRANSECT
The results of aldicarb analyses for the eight profile
wells constructed during the NYSDOH study are presented in
Figure 8-1. Also shown are results from private wells along
20
the transect for which information on screen depth was known.
Aldicarb contamination was found at shallow depths (less
than 40 feet below the water table) on the northern and southern
portions of the transect, and at depth (up to 100 feet below the
water table) near the center of the transect. Since aldicarb
was first used in 1976, only five years ago, it is not surpris-
ing that contamination at depth is presently limited to the
central portion of the fork where vertical movement is greatest.21
Because aldicarb was applied almost universally to potato
fields, if it proves to be conservative within the saturated
zone, it can be expected to spread throughout the entire aquifer
22
in farming areas, just as nitrate and chloride have done already.
The length of time it takes before a particular portion of the
aquifer becomes affected will depend upon its location; agricul-
23
rural well pumpage may accelerate contaminant movement locally.
Concentrations at depth will be less than those presently
found in the shallow portions of the aquifer due to mechanical
20. Depth information on private wells was provided by the
owners and may not be too reliable; for example, according to
the information provided, three of the private wells would be
screened above the water table (Figure 8-1).
21. See Section V and Appendix D.
22. See Sections VI and VII.
23. See Appendices D and E, and Section IX, B.
- 56 -
- 57 -
dispersion; this process, however, will probably reduce con-
centrations by less than an order of magnitude, so that most
of the aquifer will experience peak concentrations approaching
or exceeding the 7 ppb level.24 Levels will begin to decline
at any point within the aquifer as the main "slug" of aldicarb
contamination passes by. The length of time that a particular
point (i.e., well) will be contaminated with aldicarb will de-
pend on a number of factors, including the length of time
aldicarb continues to be leached out of the soil column, and
the amount of dispersion that has occurred during travel
through the aquifero25 Because groundwater moves so slowly
on the North Fork, it will probably take over 100 years for
the entire aquifer to purge itself of aldicarb.26
C. ALDICARB - CUTCHOGUE AND MATTITUCK HOT SPOTS
Aldicarb concentrations at the Cutchogue hot spot are
presented in Figure 8-2. The data are from three profile
wells installed by SCDHS during the study, two fire wells,
and six private wells along Harbor Lane for which depth in-
formation was known. Aldicarb contamination appears to be
24. This conclusion is based on the evaluation of chloride
and nitrate data for deeper portions of the aquifer collected
during this study.
25. The amount of dispersion will depend on the ground-
water velocity and the distance the "slug" has traveled.
26. This assumes that aldicarb will not decay or be de-
graded within the saturated zone during this period of time.
Mechanical dispersion would cause aldicarb residence times to
exceed those calculated in Appendix D for the groundwater
itself.
- 58 -
- $9 -
limited to the upper 30 feet of the aquifer in this shallow
flow region.27 Contamination in fire well 23 probably origi-
nates in fields to the north. In time, contamination from the
north can also be expected to affect water at depth (below
30 feet) below the rest of the hot spot.
Aldicarb contamination at the Mattituck hot spot also
appears to be limited to the upper 30 feet of the aquifer
(Figure 8-3). Well defined aldicarb plumes appear to extend
from upland farms downgradient to Long Creek. Again, deeper
portions of the aquifer will probably be affected in time as
a result of lateral and upward regional flow.
27. The presence of aldicarb at depth within the zone of
diffusion (well S-71188) is somewhat surprising; however, the
flow field within the zone of diffusion can be quite complex.
- 60 ~
S-7~087
F.if. 9
14,
S-71089
7.I~. 8
I
I
3
FIG. 8-3 ALDICARB: MATTITUCK HOT SPOT
- 61 -
IX. Dichloropropane
A. DICHLOROPROPANE - GENERAL
Pesticides containing 1,2 dichloropropane have been used
since the early 1950s on North Fork fields that were quaran-
28
tined by the USDA because of golden nematode infestation.
The SCDHS began regular testing for the compound in 1980. Thus
far, groundwater contamination has been found in only a few
agricultural communities.
In Cutchogue, dichloropropane was found in 17 of 33 wells;
two approached or exceeded the NYSDOH standard of 50 ppb on two
29
successive samplings. In Mattituck, 2 of 9 samples were con-
taminated at levels of 10-15 ppb. One well of 16 in Southold
was contaminated, with a concentration of 49 ppb.
B. DICHLOROPROPANE - NORTH FORK TRANSECT
The results of analyses for dichloropropane at the eight
profile wells and at a number of private wells in the northern
portion of the transect are presented in Figure 9-1; the years
that pesticides containing dichloropropane were applied to
fields along the transect are indicated on Figure 9-2. Fields
on the northern portion of the transect were treated as long
ago as 1951; this, however, does not fully explain the presence
28. The compound is also used in industrial processes, and
has been found in groundwater in non-agricultural areas. Pesti-
cides containing 1,2 dichloropropane include DD, Vorlex, Vidden
D, and Telone (small percentage, mostly 1,3 dichloropropene).
29. The state standard is 50 ppb for any single organic
contaminant in drinking water.
62 -
7 T
63 -
1971
FIG. 9-2 DICHLOROPROPANE
TREATED FIELDS:
NORTH FORK TRANSECT
- 64 -
of dichloropropane at depths down to -60 ft. MSL north of Oregon
Road, where the water is much older than 30 years.30 It is
most likely that large agricultural wells and the collective
effect of small private wells have caused an accelerated down-
31
ward migration of contamination. This same mechanism is also
likely to affect aldicarb contamination.
The absence of dichloropropane from samples taken from the
southern portion of the transect does not necessarily mean that
this portion of the aquifer is free from contamination. Unlike
aldicarb, dichloropropane was not universally applied, and it
is likely that the profile wells installed during this study
did not intercept the contamination plume of a treated field
(Figure 9-2). Nevertheless, wells downgradient (south) of
treated fields; e.g., the well at the Cutchogue School, will
probably be impacted within a few years.
C. DICHLOROPROPANE - CUTCHOGUE AND MATTITUCK HOT SPOTS
None of the samples taken at the Cutchogue and Mattituck
hot spots showed dichloropropane contamination (see Appendices
B and C). A check of USDA records for fields within a half-
mile upgradient of the hot spots found that none had been
quarantined, and, presumably, none had been treated with pesti-
cides containing dichloropropane.
30. See Section V and Appendix D.
31. Large agricultural wells are located near well S-71282
and between wells S-71285 and S-71283 (see Appendix E). About
15 houses and a motel are located north of well S-71286.
- 65 -
X. Monitorin~ Pro~ram
Contamination of the North Fork's groundwater by agricul-
tural chemicals will persist well into the next century, even
if agricultural practices are modified so as to prevent further
leaching of these chemicals. The potential threat to public
health will also persist, not just from nitrates, aldicarb, and
dichloropropane, but from numerous other chemicals.
Future monitoring efforts should be carried out at three
different levels. First, surveillance of private wells for
nitrate, aldicarb, and other agricultural chemicals should
continue. Sampling schedules should continue to be based on
the distance to farm fields, with houses closest to and down-
gradient of fields receiving the highest priority. Data from
private well surveillance will not only serve to protect the
public health, but will also provide a good data base with
which to track the large-scale movement of agricultural chemi-
cals through the upper portions of the aquifer.
Second, an ongoing monitoring effort should also be
initiated to track the vertical and horizontal movement of
contamination through the deeper portions of the aquifer.
Additional wells at intermediate depths should be added to
the paired wells now in place along the North Fork transect;
additional wells should be installed to provide more complete
spatial coverage. Frequent sampling should be conducted at
these wells (e.g., bi-weekly) to develop a sufficient data
66 -
base on which to do statistical evaluations; without these
evaluations, the representativeness of individual sample
analyses cannot be determined, nor can the health risks be
accurately assessed. On a regional scale, contamination in
the deeper portions of the aquifer should be tracked by making
use of selected agricultural wells, supplemented by additional
observation wells; priority should be given to areas considered
as potential water supply well fields.
The third level of monitoring effort should be made at
selected farm fields that were treated with aldicarb; these
fields should represent a number of conditions, including soil
type (clay content) and depth to groundwater. Continuous
sampling should be conducted at these sites to determine the
amount of aldicarb still tied up in the soil column (if any)
and the leaching rate to groundwater. Monitoring of shallow
groundwater directly below the field and immediately down-
gradient should be conducted on a continuing basis to establish
the statistical variability and, most important, to identify
trends and determine the degradation rate (half-life).
- 67 -
XI. Findings, Conclusions, and Recommendations
A. FINDINGS
1) The amount of fresh groundwater available east of
Mattituck is limited by the presence of salty groundwater at
the coastlines and a thick clay layer only 100 feet (or less)
below the water table.
2) The residence times of recharged precipitation within
the groundwater aquifer increase with increasing distance from
shore; near the center of the North Fork, residence times ap-
proach 150 years.
3) The conservative agricultural chemicals nitrate and
(potassium) chloride, which have been in long-term use, are
pervasive within the aquifer below and downgradient of farm
fields.
4) Aldicarb contamination is presently limited to the
upper 30-40 feet of aquifer except in the central recharge
portion of the North Fork, where it has been detected near
the bottom of the aquifer (100 feet below the water table).
5) The pumping of agricultural irrigation wells has
probably accelerated the downward movement of nitrate and di-
chloropropane contamination.
B. CONCLUSIONS
These findings imply that:
1) Aldicarb, if it proves to be conservative in ground-
water, will eventually contaminate most of the North Fork
- 68 -
aquifer, even though additional inputs have ceased; concentra-
tions will probably approach or exceed the 7 ppb drinking water
guideline.
2) If the above is true, it will take over 100 years for
the groundwater system to purge itself of aldicarb, and recourse
to deeper'private wells to avoid aldicarb contamination is only
a temporary solution to water supply problems.
C. RECOMMENDATIONS
1) Surveillance of private wells should continue in order
to protect the consumer and to track pollution in the upper por-
tions of the aquifer; sample analysis should be expanded to
include other agricultural chemicals.
2) A surveillance network that includes agricultural wells
and deep monitoring wells should be established to monitor con-
taminant movement in the deeper portions of the aquifer; and a
sampling program at farm fields should be conducted to determine
the soil storage, leaching rate, and degradation rate of aldicarb.
3) Planning and engineering studies should continue in
order to reduce future contaminant loadings and to find viable
alternatives for supplying North Fork residents with safe
drinking water.
- 69 -
Bibliography
Baier, Joseph and Dennis Moran. 1981. "Status Report on
Aldicarb Contamination of Groundwater as of September
1981." Suffolk County Department of Health Services.
Hauppauge, New York.
Crandell, H. C. 1963. "Geology and Ground-Water Resources
of the Town of Southold, Suffolk County, New York."
USGS Water Supply Paper 1619-GG.
Franke, O. L. and Philip Cohen. 1972. "Regional Rates of
Ground-Water Movement on Long Island, New York." USGS
Prof. Paper 800-C.
Geraghty & Miller, Inc. 1977. "Hydrologic Impact Caused by
Proposed Dewatering on the Long Island Lighting Company
Tract, Jamesport, New York." Syosset, New York. (Un-
published Consultant's Report). March 1977.
Guerrera, August A. 1981. "Chemical Contamination of Aquifers
on Long Island, New York." Journal AWWA 73(4), April 1981.
Hoffman, John F. 1961. "Hydrology of the Shallow Ground-Water
Reservoir of the Town of Southold, Suffolk County, Long
Island, New York." State of New York Water and Resources
Commission, Bulletin GW-45.
H2M Corp. 1970. "Comprehensive Public Water Supply Study:
Suffolk County, New York." CPWS-24, Volumes I, II and III.
Melville, New York.
H2M Corp. 1974. "Water Quality Study in the Town of Southold."
Melville, New York.
H2M Corp. 1978. "Section 201 - Wastewater Facility Plan of
the Mainland Portion of the Town of Southold." Prepared
for the Town of Southold and Incorporated Village of
Greenport. (Unpublished Draft Consultant's Report).
August 1978.
INTERA Environmental Consultants, Inc. 1980.
Simulation of Aldicarb Behavior on Long
rated Flow and Ground-Water Transport."
USEPA. December 1980.
"Mathematical
Island: Unsatu-
Prepared for the
Jensen, H. M. and Julian Soren. 1971. "Hydrogeologic Data
from Selected Wells and Test Holes in Suffolk County,
Long Island, New York." Published by SCDEC.
- 70 -
Bibliography (continued)
Malcolm Pirnie Engineers. 1967. "Town of Southold, Suffolk
County, New York: Investigation of Water Resources."
White Plains, New York.
McClymonds, N. B. and O. L. Franke. 1972.
Properties of Long Island's Aquifers."
627-E.
"Water-Transmitting
USGS Prof. Paper
Pacenka, Steven and Keith S. Porter. 1981. "Working Paper:
Assessment of the Environmental Fate of the Potato Pesti-
cide, Aldicarb, in Soi~ and Ground Water: Eastern Long
Island, New York." Water Resources Program, Center for
Environmental Research, Cornell University, Ithaca, New
York.
Soren, Julian. 1977. "Ground-Water Quality Near the Water
Table in Suffolk County, Long Island, New York." Long
Island Water Resources Bulletin LIWR-8. Prepared by the
USGS for the SCDEC.
Talmage, A. N. 1977. "The Growth of Agriculture in Riverhead
Town, Suffolk County, New York." Riverhead, New York.
Suffolk County Historical Society.
Underwood, F. L. 1933. "Costs and Returns in Producing
Potatoes in New York in 1929." Cornell University Agri-
cultural Experiment Station. Ithaca, New York.
Woodward-Clyde Consultants. 1977. "Assessment of Geohydro-
logic Conditions: North Fork and Shelter Island, Long
Island, New York." Prepared for the LIRPB. Hauppauge,
New York. April 1977.
- 71 -
APPENDIX A
WATER QUALITY DA?A SUMMARY: NORTH FORK TRANSECT
Sa~l~ De.ch*
Well % (T~t~ Sampled) Ckloride (~cm) Nitrate (~) Aldicarb
1,2 DJ. chlo~'opane
S--71286 (8./28/81)
20 42 6.5 <1.0 <2
40 40 3.9 <1.0 <2
60 47 5.4 <1.0 <2
80 42 5.3 <1.0 6
90 540 3.5 <1.0 4
100 18,000 1.0 <1.0 <2
S-71285 (9/4/81)
20 22 6.9 40 <2
40 34 7.1 ~1.0
60 31 .5.2 <1.0 15
80 27 2.4 <1.0 <2
100 28 3.0 <1.0 <2
(9,/10/Sl)
20 54 10.0 84
40 48 6.9 <1.0
60 48 9.3 <1.0
80 47 8.0 <] .0
100 18 0.2 <l.n
5-71283
5-71282
(8/25/81)
25 51 7.5 <1.0 .~2
45 56 8.6 <1.0 5
65 64 11.0 <1.0 16
90 57 8.9 (1.0 13
5-7~
(7/13/81)
30 8 0.3 <1.0
50 15 0.8 <1.0
70 11 O.S 1.0
90 11 0.6 <1.0
110 460 4.7 <1.0
5-71280
(8/].9/81)
10 29 11.0 18.o ,~2
30 26 7.6 <1.0 <2
50 34 13.0 4.0 <2
?0 27 9.0 3.0 <2
90 20 4.5 <1.0 <2
110 12 2.4 1.0 < 2
5-7~78
(8/4/81)
X0 34 7.6 <2
30 10 8.2 <1.0 <2
50 14 4.2 < 1.0 "~ 2
70 22 6.0 <1.0 <2
90 27 6.0 <1.0 <2
115 27 5.2 <1.0 <2
130 9 0.2 < 1.0 < 2
A-1
APPENDIX A
(cont'd)
Sable De,ch*
~ell # (Date Sailed) (~],oride
S-7~276 (7/27/8X)
? X4
27 23
37 22
4'7 16
S-'71275'* (7/21/81)
15 74
35 320
45 5,600
55 9,800
65 11,000
75 12,000
S-71274'* (7/22/81)
25 37
5-71045** (6/24/8].)
20 -
40 -
60 -
80 -
100 -
120 -
8,7 <1.0 <2
6.1 <1.0 <2
6.2 <1o0 <2
7.8 5
30.0 <1.0
1.2 <1.0
.OS <1.0
.03 <1.0
.03 <1.0
5.9 15.0
<1.0
5.0
<1.0
<1.0
<1.0
A-2
APPENDIX B
WATER QUALITY DATA SUMMARY: CUTCHOGUE HOT SPOT
we.11 !
5-71188
Sable
(Oa~.e Sailed) C'~lo=i~e (p;:~ Nitra~ (pp~) .~.lc~carb
(7/2L'81)
5 2,200 6.7 5.0
15 170 1.3.0 <1.0
25 1,000 8.5 6.0
35 16,000 8.5 6.0
45 3,600 8.3 5.0
55 LO,OhO 1.0 <1.0
1,2 Dichlozopropane (ppb)
<2
<2
<2
<2
<2
<2
5-71187 (7/22/81)
11 16 4.7 17.0 <2
21 38 12.0 53.0 < 2
31 49 1~.0 3.0 < 2
41 38 ]3..0 <1.0 <2
51 23 7.4 <1.0 <2
5-71186
(7/33/81)
7 33 8.7 20.0 <2
17 46 8.2 22.0 <2
27 32 9.3 l.O <!
37 30 9.0 <1.0 <2
5-71190 (7/27/81)
10 45 16.0 43.0 < 2
20 50 11.0 3.0 <2
30 52 5.8 47.0 <2
40 24 8.4 <1.0 <2
50 22 8.2 <1.0 <2
5-72268 (a) (2/3/82)
5 9.1 1.9 <1.0 <2
S-72269 (a) (2/3/82)
20 40 11.0 20.0 <2
S-72270 (a) (2/4/82)
40 44 12.0 <i.0 <2
S-72266{b) (2/8/82)
7 44 7.9 - <2
S-72267 (b) (2/8/8:~
27 34 8.1 - <2
5-72264 (a) (2/2/82)
10 2~ 7.1 3.0 <2
5-72265 (¢) (2/2/82)
30 25 8.2 <l.O <2
Fire ~ '=116'* (11/16/81)
4 38 13.0 40.0 < 2
Fire ~-ll 123'* (11/16/81)
4 29 7.0 9.0 <2
*A~p=u~mate depth of to9 of 2 foot screen, in feet
**Top of 20 foot screen, i~ feet below MSL.
(a) - ~djacent to well S-71187.
(b) - ~djacent to well S-71186.
(c) - Adjacent to w~ll S-71190.
APPENDIX C
WATER QUALITY DATA SUMMARY: MATTITUCK HOT SPOT
Sample r=w: '~*
(D~ts Sampled (~.loride (~m~) Nitrate (~) Aldicarb (ppb) 1,2 D£chlozopro~ane (ppb)
S-71087
(7/13/81)
13 2,100 0.1 < 1.0 <2
23 1,400 2.6 < 1.0 <2
33 150 5.9 < 1.0 <2
43 200 7.3 < 1.0 <2
53 110 8.0 < 1.0 <2
~71~8
(7/1~/81)
2 38 3.4 <1.0 <2
12 54 7.5 < 1.0 < 2
22 190 2.0 <1.0 <2
32 59 0.5 <1.0 <2
42 51 0.? < 1.0 < 2
~71~9
(7/15/81)
3 150 1.S <1.0 < 2
13 190 1.6 <1.0 < 2
23 220 1.5 <1.0 < 2
33 32 2.9 < 1.0 < 2
43 27 1.9 <1.0 < 2
S-71090
(7/7/81)
2 38 8.5 59.0 <2
12 37 10.0 37.0 <2
22 35 7.0 <1.0 <2
12 42 6.7 <1.0 < 2
42 48 8.1 <1.0 <2
52 49 11.0 <1.0 <2
62 45 8.4 <1.0 <2
(7/10/8!)
8 33 12.0 102.0 < 2
18 25 10.0 65.0 < 2
28 21 11.0 32.0 -
38 23 8.7 1.0 < 2
48 29 9.7 < 1.0 < 2
~ We. ll J3** (1L/4/81)
4
46 7.3 < 1.0 < 2
~ Well. J14**(ll/&/81)
13
33 13.0 25.0 < 2
~ Well IS** (11/4/81)
44
19 2.2 <1.0
FLce~,le11 19'* (11/4/81)
i 18,000
0.2 <2
*Ap~ox~ate depth of top of 2 foot screen, in feet be/ow ~L.
*'*~'~ of 20 foot scr~m, in feet below ~L.
C-1
APPENDIX D
VELOCITY FIELD CALCULATIONS: NORTH FORK TRANSECT
A. Average Linear Velocity
The velocity field for the Depot Lane transect was deter-
mined using Darcy's law, which states:
v ='K ~1
where,
v = specific discharge (volumetric flux per area)
(ft/day);
K = hydraulic conductivity (ft/day); and,
hydraulic (head) gradient along length 1 (dimension-
less).
The average linear velocity ~ can then be defined
v K ~h
where,
as:
n = the volumetric porosity of the medium (dimensionless).
B. Horizontal Hydraulic Conductivity
For the purposes of this analysis, the upper sand and
gravel aquifer in the area of the transect is assumed to be
homogeneous (see Figure 4-3). Measured and estimated hori-
zontal hydraulic conductivities for the upper glacial aquifer
along the north shore of eastern Suffolk and the North Fork vary:
Approximate
Avg. Value
(ft/day)
425
200
Method
pump test
specific
capacity
Location
Jamesport
North Central
Suffolk Co.
Reference
Geraghty & Miller,
1977, p. 27.
McClymonds & Franke,
1972, p. E 15.
D-1
For this analysis, korizontal hydraulic conductivity (Kh)
of 300 ft/day was used. (This value is close to the average
value of 270 ft/day estimated by the USGS for the upper glacial
aquifer, see Franke and Cohen, 1972, p. C271).
C. Anisotropy
Estimated values of anisotropy (ratio between vertical
and horizontal hydraulic conductivity) for the upper glacial
aquifer also vary. The general rule-of-thumb used by the
USGS is 1:10 (Franke and Cohen, 1972, p. C271). On the North
Fork, however, there appears to be an absence of significant
layering in the upper glacial aquifer deposits that would re-
sult in large differences between vertical and horizontal
hydraulic conductivity (Julian Soren, USGS, personal communica-
tion on 1-21-82). Pump tests at Jar~esport have indicated that
the water-table aquifer in the glacial outwash deposits is
highly isotropic on the site, with a ratio of about 1:5 (Geraghty
& Miller, 1977, p. 27). A value of 1:5 was used in this analysis.
D. Vertical Hydraulic Conductivity
Using a value of Kh = 300 ft/day and an anisotropy of 1:5,
the vertical hydraulic conductivity Kv used in this analysis
was 60 ft/day.
E. Porosity
The computed porosity of upper glacial aquifer materials
at Jamesport ranged from 30-50 percent (Geraghty & Miller, 1975,
p. 18). A typical porosity range for glacial till is 25-45
percent; fine sand ranges 40-50 percent; and coarse sand ranges
D-2
25-35 percent. A value of 35 percent was used for this analysis,
since the material is fine to coarse sand with grit and gravel
(see Figure 4-3).
F. Head Measurements
Monthly head measurements were made at each well along
the transect using a steel tape. Measurements for the period
October, 1981 to February, 1982 are presented in Table D-1.
These values were then plotted on a cross-sectional map along
the transect, and contour lines were drawn (see Figure D-i).
G. Vertical Flow
Using the equation presented in Section A and the data
tabulated in Table D-l, the vertical components of flow were
calculated for each paired set of wells (see Table D-2).
Average head values (elevations) for the water table were
then determined from average measurements in shallow wells
(see Table D-i) and were adjusted, where necessary, to -10
MSL using the gradients from Table D-2. Vertical flow com-
ponents and water-table elevations were then plotted on
Figure D-1.
ft.
H. Horizontal Flow
Using the equation presented in Section A and the water-
table elevations plotted on Figure D-l, the horizontal veloci-
ties near the top of the aquifer were calculated (see Table
D-3). Representative values were then plotted on Figure D-l,
and additional values at depth were calculated using the
equipotential lines. As can be seen in Figure D-l, horizontal
velocities increase toward the shoreline and decrease with depth.
D-3
- (.r**.,T)
D-5
TABLE D-2
VERTICAL VELOCITIES: NORIH FORK TRANSECT
From To
Well % Well
S-71286 S-71287
S-71283 S-71284
S-71171 S-71191
S-71280 S-71281
S-71278 S-71289
S-71276 S-71277
6O
* v=
** actual
Ah (ft) A1 (ft) Ah/A1
-.02 55 3.6 x 10-4
0 70 0
+.05 80 6.2 x 10-4
+.02** 75 2.0 x 10-4
+.02 85 2.4 x 10-4
-.05 40 1.2 x 10-3
ft/day Ah
.35 (~-~),positive downward.
value used .015, see Table A-1.
(ft/day)
-.06
0
+.11
+.03
+.04
-.21
HORIZONTAL
TABLE D-3
VELOCITIES: NORTH
FORK TRANSECT
From To
Well # Well % Ah (ft) A1 (ft) Ah/Al*
S-71286 S-71285 +.52 1250 4.2 x 10-4
S-71285 S-71283 +.34 1000 3.4 x 10-4
S-71283 S-71282 +.57 2500 2.3 x 10-4
S-71282 S-71171 +.33 2500 1.3 x 10-4
S-71171 S-71280 -.16 2000 0.8 x 10-5
S-71280 S-71278 -.84 3000 2.8 x 10-4
S-71278 S-71276 -1.22 2500 4.9 x 10-4
(ft/day)**
+.36
+.29
+.20
+.11
-.07
-.24
-.42
* slope of water
300 ft/day
** ~ = .35
table between wells assumed
Ah
~A--f~, positive northward.
to be linear.
D-6
I. Residence Time (Time of Travel)
Residence times for six representative flow paths through
tke aquifer were calculated (see Figure D-1 and Table D-4).
The time of travel appears to vary proportionally with the
square of the distance from shore.* Residence times of 100
years and more were found for water recharged near the center
of the fork, although the time required to reach depth is only
about 3 years. Water recharged above areas with primarily
horizontal flow have residence times of up to 30 years. All
these values are approximate; given the various uncertainties
in the analysis, these values are probably accurate to within
±25 percent.
*The constant of proportionality is about 1.8 when distance
from shore is measured in thousands of feet, and time is measured
in years.
D-7
D-8
APPENDIX E
AGRICULTURAL WELL PUMPAGE: NORTH FORK TRANSECT
Five large agricultural wells lie within 500 ft. of the
transect (Figure E-l). They range in size from 300 gallons per
minute (gpm) to 600 gpm.
over 31 ft. (Figure E-i).
these well screens in the
Screen lengths vary from 15 ft. to
The effect of partial penetration of
100+ ft. thick aquifer is to produce
vertical head gradients and flow patterns near the well. While
it is not possible to precisely calculate the vertical velocities
produced by an individual well, the effect of well pumpage can
be inferred from water quality on the transect. For example, the
movement of dichloropropane to depths up to -80 ft. MSL near well
S-71282 (see Figure 9-1) was probably accelerated by the pumping
of agricultural well 8134 (Figure E-l); similarly, contamination
in well S-71285 (see Figure 9-1) at depths up to -60 ft. MSL is
probably related to the pumping of agricultural well 8135
(Figure E-l). It is also implied that pumping of these and other
wells will accelerate the downward movement of aldicarb.
The radius of influence of a 500 gpm well is calculated as
about a mile using the formula of C. E. Jacob:
R = ~ 2.25 Tt S
where,
R = radius of influence (ft.),
T = transmissivity (ft /day) = 30,000,
E-1
APPENDIX E
(cont'd)
t = number of days = 60, and
S = storage coefficient = .15.
Drawdowns of the water table, however, are less than 1 ft. at a
distance of 1000 ft., and 5 ft. right at the well. These values
were calculated using the Dupuit-Forchheimer equation:
z Q R½
sr = hO - (hO - ~ in F)
where,
r
= drawdown at a distance r from the center of a pumping
well (ft.),
ho = height of the water table before pumping .(ft.) = 100,
Q = discharge of pumping well (gallons/day) = 720,000,
K = hydraulic conductivity of the aquifer (gallons/ftZ/day)
2,250,
R = radius of influence (ft.) = 5196, and
r = distance from the center of a pumping well (ft.).
The effect on the local water budget of a 500 gpm well is to use
(although not necessarily consumptively) the annual recharge
(20 inches) to the area within a 1,050-foot radius of the well.
E-3
APPENDIX F
DISCUSSION OF CHLORIDE DATA: NORTH FORK TRANSECT
Figure 5-2 (reproduced as Figure F-l) shows that the
freshwater-saltwater interface along the north shore above the
clay is a sharp boundary; chloride levels increase from 42 to
540 ppm in just 10 feet, and then increase to 18,000 ppm in
another 10 feet. The interface above the clay appears to
closely follow the Ghyben-Herzberg relation; the water level
in well S-71286 is about 2.1 feet MSL (Figure D-l), while the
interface is found approximately 40 times as deep (-85 feet
MSL). The position of the interface on the south (Cutchogue
Harbor) is inferred from data for well S-71276.
The chloride (and nitrate) values at well S-71171 appear
to be close to natural background levels, except at the level
just above the clay layer (see Figures F-1 and 7-2). This
well is located at a recharge basin that drains County Route
27 (Middle Road) and receives runoff from agricultural fields
(primarily during early spring, when the ground is frozen).
Since the basin is located at the top of the groundwater di-
vide, flow is essentially vertical, and the well is probably
sampling only recharged runoff, which appears to be of better
quality when compared to water that leaches through active
farm fields. Data for well S-71171 should not be interpreted
as implying that the central portion of the fork has escaped
the impacts of agricultural chemicals.
F-1
/
~ /
/
/
I
I
I
T
The anomalous chloride (and nitrate) values for well
S-71171 just above the clay layer may indicate the presence of
a leachate plume originating at the Southold Town landfill lo-
cated 2,000 feet to the north (see Figure 3-4). Previous drill-
ing at the landfill has indicated that the clay layer is at a
higher elevation than at the sump (sea Figure 4-4)i Landfill
leackate, which is denser than surrounding waters, may be
travelling down the slope of the clay layer, even though this
direction is somewhat against the regional gradient of ground-
water flow. This hypothesis is supported by sampling results
for wells downgradient of the landfill, which have not shown
leachate contamination.
F-3
APPENDIX G
WELL CONSTRUCTION DATA
S-71286 PtofLle
S-71285 Profile
S-71283 Pzofile
S-71282 P:ofile
S-71171 P~ofile
8-71280
8-71278 Profile
S-71276 Pzofile
8-71275 Profile
S-71045 Profile
S-71287 C~servation
S-71284 Observation
S-71191 Observation
S-71281 O~rvatic~
8-71289 Cbsezvatiaa
S-71277 Observation
S-71044 Geologic
S-71170 ~ologic
S-?1279 GeologY=
8/31/81
9/4/81
9/10/81
8/25/81
7/13/81
8/19/81
7/30/81
7/27/81
7120181
6/24/81
9/1/81
9/11/81
7/16/81
8/21/81
8/14/81
7/22/81
9/2a/81
7/8/81
e~4/8~
S-71186 ~:o~11e 7/30/81
~-71187 ProfLle 7~81
~7~88 ~f~e 7~0/81
~7~90 ~e 7~3/81
S-722~ ~ ~/82
~72265 ~t~n ~/82
~72266 ' ~ 2/8/82
S-72267 ~t~ 2/2/82
~722~ ~t;~ 2/3/82
S-72269 ~ 2/3/82
S-72270 .~ 2/4/82
~71~7 ~file 7~3~1
~71~8 ~e 7~6/81
S-71~9 ~f~e 7~/81
~71090 ~f~e 7/6/81
S-71091 ~e 7~/81
20-24
19-23
19-23
7-11
28-30
12-14
9-11
7-11
15-19
20-22
75-80
90-95
109-114
86-91
94-99
48-52
15-25
0-2
11-13
5-7
10-12
10-12
30-32
7-9
27-29
5-7
20-22
4O-42
3-5
2-4
1-3
2-4
0-2
+ Wells =~structed for t]~ NYS~ Study.
*Screen interval, in feet below ~L.
G-1
FIELD NO.
COl- BY
DATE COL.
TIME COL.
APPENDIX H
SCDHS CHEMICAL ANALYSIS
FORMS
NAME OR FIRM
ADDRE$~ OR LOCATION
fOINT OF COLLECTION
REMARKS/INSTRUCTIONS
ILABORATORY I
LAB NO.
(GROUNDWATER SECTION) TYPE SAMPLE
DATE REC'VD.
TiME REC'VD.
DATE COMPLETED
SUFFOLK COUNTY HEALTH SERVICES LABORATORY
CHEMICAL EXAMINATION OF WATER, SEWAGE, INDUSTRIAL WASTE
Observation Well
TEST RESULT
TEST RESULT TEST RESULT liter
=ONDUCT un-,ho ]( NITRATE-N COPPER
~H X NITRITE RON
%'EST RESULT ~ X AMMONIA-N MANGANESE
h. ALKALINITY TKN CHROMIUM
I'. ALKALINITY D-PO~l-P NICKEL ·
X =HLOR'IDE ZINC
FLUORIDE MAGNESIUM
:YANIOE TOT. SOL105 CALCIUM
;US. SOLIDS LEAD
SULFATE DISS. ~OLIDS CADMIUM
MBA~ SILVER
P..O.O. SODIUM
T.O.C. POTASSIUM
BARIUM
FIELD D.O.
FIELD TEMP
FIELD RH
~'~.eld A1ka. I X FIELD COND. umho X D.T.Wo
H-1
APP, ENDIX H
(cont'd)
Lab No. TO-
Field No.
Date
(Nime not In£tLals)
(Groundwater Section)
Received in Lab
Othe~
Date Com~feced
Ham
Lo~ation o~ well:
· oi~t o£ Co%lection
~e~arkst
SUFFOLK COUNTY DEPARTH£HT OF H£A/,TH SERVICES
D:It,~SZON OF HEDZCAL LEGAL ZNV~STZGAT[ONS & FORENSZC $CZENCE$
PUBLIC HEALTH LABORATORY
T~AC~ O]U3ANIC ANALYSIS OF
USGS/
SCDHS
(Temik
,Study) Owne~
Wel~ No'. S- Depth:
SEND RESULTS TO: Richard Markel., Health Services
225 Rabro Drive, Hauppauge
ft.
305
200
323
30O
324
321
304
294~ I
40S
310
303
293
311
302
Compound
Hethylene chi~ridm.
1,1 Dichloroeth&nu
T=ans Dicltloroe~.hyl~e ........
Chlozo£om ....
~,2 Dlchlu=oe~hane .......
~,1,1 Tri~hlo=oet~ane
Carbon Tet=achlorl~e.
I Bromo-2~Chloroethan~o
1,2 Dl¢~loro~=o~ane ......
1,1,2 T=i=hlo~oet~ylene ......
C~lo:o41b=omomethane. G .......
1,2 Dlbr~moet~ane..
2~Bromo-l-Chlozop~o~ane ......
CIs-Dlch[o=oe~h~[ene°..~
p-Xylene ........................
Xylene (a) ......................
£thylbenzene ....................
o-Chlorotoluene .................
m-Chlorotoluene
p-Chlorotolue~e .................
Chlorotoluen~ {$) ...............
m-Dlchlozobenzene ...............
Q-Dlchlo~obenzene ...............
.,2,4 Trimethylbenzene ..........
2,3 Di~hloroprope~e .............
1,1,~ Trichloroethane ...........
1,2,2,3 Tetrachlo~propane .......
~b
H-2