HomeMy WebLinkAbout2.00 ISDS Informationa
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LOS AMIGOS RANCH PUD
INDTVIDUAL WASTEWATER
TREATMENT SYSTEMS
GROUND WATER IMPACT
Prepared By:
Resource Engineering, lnc.
909 Colorado Avenue
Glenwood Springs CO 81601
(9701945-6777
April 6, 1998
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FIEi SOUFICE
ENGi!NEEFIING
Mr. Michaet Erion, PE
Wright Watelr Engineers
PO Box 219
Glenwood Springs CO 81602
rNC
Apri! 6, 1998
BE: Los Amigos Ranch PUD Individual Wastewater Treatment System lmpacts
Dear Michael:
This letter is provided pursuant to the Garfield County Planning and Zoning Commission
condition of approval for the Los Amigos Ranch PUD, Filings 6-10 which states:
'That prior to the approval of the Board of County Commissioners of the
Prelir,ninary Plan for Los Amigos Filings 6-1O, the applicant shall develop
a groundwater quality monitoring plan and mitigation plan, or in the
alternative, develop a new proposal that eliminates the need for a
monitoring and mitigation plan, to be reviewed and recommended for
approval by the County's consulting engineer.'
The proposal outlined in this letter is based on additional literature review, technical
information and knowledge of the groundwater quality in the vicinity of County Road
114 and Hrary 82. The additional information has enabled us to refine our opinion of
the impacts to groundwater resulting from the proposed 168 lndividua! wastewater
treatment srfstems in LosAmigos Ranch PUD Filings 6-1O. The information has also
enabled us to present a pro-active plan for technologically advanced individual
wastewater treatment systems for Los Amigos. The opinion and plan presented herein
supercedes our'opinion expressed in the Resource Engineering, lnc. letter to Mr. Greg
Boecker dated February 28, 1998 (attached).
SUMMARY OF OPINION
It is the opinion of Resource Engineering, lnc. that there is no risk of groundwater
contaminationr as a result of properly designed, installed and maintained individual
sewage treatment systems in Los Amigos Ranch. There is a possibility that the nitrate
level in the groundwater down gradient of Los Amigos Ranch in the vicinity of County
Road 1 14 and Hwy 82 will increase slightly as a result of the individual sewage
treatment s'ystems. We have calculated that nitrate levels may increase by a factor
ranging fronn 0.16 mg/titer to 0.60 mg/liter. This compares to existing groundwater
nitrate levels in the County Road 114 - Hwy 82 vicinity ranging from O.O mgfliter to
3.5 mg/liter. The possible increased nitrate levels will not result an groundwater
lGroundwater contamination for purposes of this opinion is defined as an increase in
the nitrate le'vel of the groundwater underlying Los Amigos Ranch and surrounding properties
to a level above the drinking water standard of 10 mg/liter as established by the Colorado
Department of Public Health and Environment and the U.S. Environmental Protection Agency.
Consulting Engineens and Hydnologists
SO9 Coionado Avenue I Glenwood Spnings, CO A1 601 I t97O) 945-A777 a Fax [37O] 945-1137
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Mr. Michael Erion, PE
Wright Water Engineers
Page No. 2
contamination.
April 6, 1998
This opinion is been based on; 1 ) the information outlined in our letter of FebruarY 28,
1gg7 to Mr. Greg Boecker which is inctuded here by reference, 2) a study entitled
Methodotogy of Predict Nitrogen Loading from Conventional Gravity On-Site WW.
Treatment Sysfems by Thomas Long (attached) and 3) a study entitled Mountain
Residential Development Minimum Well Protective Distances Well Water AualitY bY
Ford, Schott and Keefe (also attached).
The opinion presented here is based on available hydrogeologic information. Actua!
conditions may vary from conditions conctuded herein. Further investigation of the
hydrogeologic conditions is beyond the scope of this document and in our opinion is
not warranted for this investigation.
The opinion is also based on the use of technologically advanced, properly designed,
installed and maintained individual wastewater treatment systems in Los Amigos.
Recommended system requirements are included later in this letter'
SITE DESCRIPTION, GEOLOGTC SETTING AND GROUNDWATER OCCURRENCE
The site description, geologic setting and groundwater occurrence in the Los Amigos
Ranch pUD vicinity *ere discussed in detail in the February 28 letter. No additional
information is provided here and the reader is referred to that letter for this background
information.
BASELINE WATER OUALITY
Water quality data from wells was obtained to determine the baseline groundwater
nitrate concentrations in the area, both up gradient and down gradient from Los
Amigos Ranch PUD. Water quality data was obtained from the Colorado Department
of puUtic Health and Environment, water Ouality Control Division (WOCD) for the wells
serving the existing Los Amigos Ranch development, Colorado Mountain College and
for four public water systemi in the County Road 114 - Hwy 82 vicinity. ln addition
to these public records a field nitrate sample was obtained on March 3, 1998 from the
collins Drilling co. well (permit #46017-F) located north of the intersection of county
Road 1 14 and Highway 82. The Spring Valley wells are indicative of the water quality
up gradient from Los Amigos Ranch and the Coltins well and the public water system
welis are indicative of the water quality below the Los Amigos Ranch'
The Colorado Mountain College and Los Amigos wells are located fairly close to each
other near the south end of the Spring Vatley. The Colorado Mountain College well
reported nitrate concentrations ranging from 0.1 8 mg per liter to 1 .1 7 mg I liter. The
a ::i:iFESOUtrCElllrr-lrrrE N G I N: = - N t; 'r a
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Mr. Michael Erion, PE
Wright Water Engineers
Page No. 3
April 6, 1998
nearby well serving Los Amigos Ranch reported nitrate concentrations ranging from
0.00 mg /liter to O.77 mg / liter. These levels are well below the drinking water
standards of 10 mg / liter.
The Coltins Drilling Co. wel! was field tested using a Hach color disk nitrate test kit
with a zero to 50 mg / liter range. A sample was obtained from a hose bib afer
a[owing the water to run for approximately 3O seconds. The test indicated that no
nitrates were present. The coltins well is topographically the highest well in the
vicinity of the intersection of County Road 114 with Hwy 82. lt is possible.that
grorni*"ter from wells nearer the river woutd exhibit some nitrates as a result of local
up gradient Individual wastewater treatment systems.
Water quality results for the welts serving the Mid Valley Mart (Hue-Mart), Mountain
Meadows Mobile Home Park, the Sopris Restaurant and H Lazy F Mobile Home Park
are attached. Nitrate levets vary from well to well and from sample period to sample
period. The highest reported level is 3.56 mg/iter at Mid Valley Mart and the lowest
irport"d reading is 0.00 mg/liter at Sopris Restaurant. The average measurement is
1 .14 mg/liter2.
All the water quality data reviewed indicates that the nitrate level in the groundwater
in the vicinity of Los Amigos Ranch is far below the drinking water standard of 1O.O
mg/liter.
LOS AMIGOS RANCH INDTVIDUAL WASTEWATER TREATMENT SYSTEM IMPACTS
A mass balance analysis was conducted to determine the impact of Los Amigos Ranch
pUD individual wastewater treatment systems on groundwater in the vicinity of County
Road 114 and Hwy 82 using reasonable engineering assumptions. The approach was
the same as that used outlined in our February 28, 1998 letter to Greg Boecker but
utilized additional research information on the fate of nitrogen from individual on-site
systems3. The calculations, atong with the assumptions used are included in
Attachment A to this letter.
Based on the results of the mass balance it is the opinion of Resource Engineering, lnc.
that individuat sewage treatment systems in Los Amigos Ranch will not cause
groundwater contamination as defined earlier in this letter. This opinion takes into
account the anticipated wastewater loading rates together with the geologic setting
2Based on the average of the highest and lowest measurement for each public water
system. See Attachment A.
3See Attachment C.
!!!i!trESoutrcEI!!'TE N G L N E E F I N G I N C
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Mr. Michael Erion, PE
Wright Water Engineers
Page No. 4
Apri! 6, 1998
and groundwater conditions described above and the existing water quality in the
County Road 114 - Hwy 82 vicinity.
The calculated increase in nitrate concentrations inthe County Road 114' Hwy 82
vicinity that may occur as a result of Los Amigos Ranch PUD individual wastewater
treatment systems ranges from a low of 0.1 6 mg/liter to a high of 0.60 mg/liter. This
may result in groundwater nitrate levets in the County Road 1 14 - Hwy 82 vicinity
ranging from 0.1 6 mg/liter to 4.1 6 mg/titer. These levels are well below the drinking
water standards set by the EPA and the Colorado Department of Public Health and
Environment.
tNDtVtDUAL WASTEWATER SYSTEM CRITERIA
The opinion of that Los Amigos Ranch individual wastewater treatment systems will
not cause groundwater contamination as defined in this letter is based, in part, on
utilization of properly designed, properly constructed and properly maintained individual
wastewater treatment systems. tn order to ensure this, Los Amigos Ranch Partnership
will implement design standards and a management plan for individual wastewater
treatment systems. These include:
1) Use of septic tank effluent fitters. These eliminate the deposition of nitrogen
rich bio-solids from septic tanks to leaching fields.
2l Use of leach field dosing systems. Dosing systems, by intermittently
discharging slugs of efftuent to the leach field, promote even distribution of
effluent throughout the leach field. This eliminates the consistently saturated
zones commonly found in "traditiona!' septic tank leach field systems. Dosing
also promotes the cyclical aerobic / anaerobic conditions needed for the
nitrification - denitrification process.
3) Annual individual wastewater system inspections performed under the authority
of the homeowners association. These inspections will ensure proper system
maintenance and identify failing systems so repairs can be made.
A proposed Los Amigos Ranch Design Standards and Management Plan is included as
Attachment B.
IMPACT OF PROPOSED DESTGN STANDARDS ON CONSUMPTTVE WATER USE
Los Amigos Ranch PUD is afforded a lega! water supply under the Basalt Water
Conservancy District's water rights plan for augmentation decreed in Case No.
87CW155. ln the plan for augmentation the decreed consumptive use rate for
o ::!!!RESOURCE!llt II'IIIENGINEERINGNC
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ti'ry ot rnG'lj'\\\\r:-
Mr. Michael Erion, PE
Wright Water Engineers
Page No. 5
April 6, 1998
individual wastewater treatment systems using leach fields is 15% of the in-house
demand. The system recommendations presented herein are consistent with the
decree. The consumptive water use in the proposed individual wastewater treatment
systems will be no different than in "traditional" ISDS systems contemplated in the
decree.
CONCLUSIONS
Additional information obtained since our tetter of February 28, 1998 to Mr. Greg
Boecker, together with a commitment to construct high quality individual wastewater
systems results in the conclusion that the Los Amigos Ranch PUD will not adversely
impact groundwater quality.
lf you have any questions regarding this please feel free to contact me.
Sincerely,
RESOURCE ENGINEERING, INC.
John M. Currier, PE
Water Resources Engineer
JMC/imc
File 7 07 '1 .0 tt" 7o7uor tmisorno2.wpd
attachments: Attachment A: Calculations
Attachment B: Los Amigos Ranch Design Standards and Management
Plan.
Attachment C: Methodoloov to Predict Nitrooen Loadino from
cffin-site ww rreat*ent suste.s
Attachment D: Mountain Residential Develooment Minimum Well
Proffi Distarces welt wate, ouatitn
Attachment E: CDPH&E drinking water test results
Attachment F: Resource Engineering, lnc. letter of FebruarY 28,1998
to Mr. Greg Boecker.
Mr. Greg Boecker
Mr. Dean Gordon
Larry Green, Esq.
:::!!EESOUtrCEallllTIIIIE N G N E E E i N G N
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D ErERM r NAillTI $,?H: A.- L.AD I N G
FROM 168 INDIVIDUAL SEWAGE TREATMENT SYSTEMS
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Determination of Nitrogen Loading
from 168 lndividual Sewage Treatment Systems,
Los Amigos Ranch P.U.D., Filings 6 ' 10
1. Total Nitrogen Loading to Drain Field
. Tota! Nitrogen into septic tanks: 36 - 94 mg/litr
. Total Nitrogen out of septic tanks: 26 -76 mg/lit2
. Note: These concentrations are based on an hydraulic loading rate of
37.4 gallon/day/capita and 2.5 persons per household3. Higher per
capita water usage would result in lower total nitrogen concentration
as the sources of nitrogen loading would remain fairly constant.
2. Nitrogen Reduction in Drain Fields
. The soils in the Los Amigos P.U.D. are generally fine grained clays
and silts (CL and ML soils) overlying sandy silty gravels (GM-GP soils)a
o A drain field in fine grained soils should remove 7Oo/o of the total
nitrogen load in the septic tank effluents.
. For this analysis it is conservatively assumed that 50% of the total
nitrogen load in the septic tank effluent will be removed in the drain
field.
tThomas Long, 1995, Methodoloov to Predict Nitrooen Loadino from Conv. GraviW
On-Site WW Treatment Svstems, Pg. 281.
2lbid, pg. 281
3lbid, pg. 281
aHepworth-Pawlak Geotechnical, lnc., February 14, 1997, Preliminarv Geotechnical
Studv. Prooosed Residential Develooment, Los Amioos Ranch P'U,D.' Countv Road 114,
Garfield Counw. Colorado.
sThomas Long, 1995, Methodoloov to Predict Nitrooen Loadino from Conv. GraviW
on-Site@, Pg.283.
April 1,1998 -1- AttachmentA-calculations
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Determination of Nitrogen Loading
from 168 lndividual Sewage Treatment Systems,
Los Amigos Ranch P.U.D., Filings 6 - 1O
. Total Nitrogen Discharged beneath drain fields
1. Low
2. High
,aL w1 \(ff)(roa.\= Tz/,13. Mean
/-3n^-1 r *s Zbps
= l,: 1'z
Note: Remember these are based on an hydraulic loading rate of
37.4 gpcd. At higher hydraulic loading rates the
concentrations would be lower.
3. Nitrate Loading to Groundwater by Mass Balance Approach
. The calculations will be done two ways:
1. 37.4 gpcd X 2.67 persons per residenceo
2. 100 gpcd X 2.67 persons per residence with a proportional
reduction in total nitrogen concentration.
6The Thomas Long report used an EPA derived 2.5 persons per residence. The Eaqle
Area Communiw Plan, November, 1995, RNL Design, Clarion and Associates and John
Humpheries Associates determined that there were 2.67 persons per residence in the Town of
Eagle and surrounding planning area. This higher number is used here.
April 1, 1998 -2- Attachment A - Calculations
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Determination of Nitrogen Loading
from 168 lndividua! Sewage Treatment Systems,
Los Amigos Ranch P.U.D., Filings 6 - 10
Precipitation lnfiltration Attenuation
1. Method 1.
1. Average leach field loading over 1,7OO acre P.U.D.
2. Total nitrogen concentration after precipitation dilution
assuming precipitation infiltration as outlined in Feb. 28,
1998 letter from Resource Engineering, lnc. to Greg
Boecker.
1. Low end drain field effluent of 13 mg /lit.
(,. 3
o.Q7 v*i
-'.Lit
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2. High end drain field effluent of 38 mg/lit.
2.54r*7
April 1, 1998 _2_Attachment A - Calculations
y','t
/' )(T)=\lr o0 bar<o. /3 21 't/frl
/3 *u1 1
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Determination of Nitrogen Loading
from 168 lndividual Sewage Treatment Systems,
Los Amigos Ranch P.U.D., Filings 6' 10
Method 2.
1. Average leach field loading over 1,7O0 acre P.U.D.
(I
)=
a
/a a Jf ")_L"
2. High end of range
f- gb F1
-/ o't
//.? b>fr(:9'*3lt '*
3. Total nitrogen concentration after precipitation dilution
assuming precipitation infiltration as outlined in Feb. 28,
1998 letter from Resource Engineering, lnc. to Greg
Boecker.
1. Low end drain field effluent of 4.86 mg/lit
/. 9ftr, + o'3{12r^:
O IAL r'-c
----'9;\,
/ lOo qa.,/(ffirWX,Bun:*r/#"kfut*,
1;" Fcrc'\ /+ I - o' ?s?s 'L/'r,.\ ./ \ rf ' / :
2. Total nitrogen strength in drain field effluent.
1. Low end of range
3?- ,( 1P.J
/r, lPcJ
3a-'/ 10u)
April 1, 1998 -4-Attachment A - Calculations
(r . 8-{ ,^Frz.,f\10.0 n-.7\ -l 0.3{?4YWll'ljTf )'L - L-zi? )_
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Determination of Nitrogen Loading
from 168 lndividual Sewage Treatment Systems,
Los Amigos Ranch P.U.D., Filings 6 - 10
2. High end drain field effluent of
)"('3y'7e xW)
14.2 mgflit
2- Zg t*?
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as outlined in Feb.
, lnc. to Gregt* 3 /na\
/iao
Method 1.
1. Low end groundwater loading of 0.87 mg/lit.
/?
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Lz /? r" \(A;r) * (/ e{r* n s.rrz)r: f.#)= C'q4'*X
2- tZ,& * 1-Of r'.' t- o' /iZ7 tL
2. High end groundwater loading ot 2.54 mg/lit.
/- 6{ r* r 2.3{?at*
fz. /ZtL+1'9{r''5 't o't=DrL)/:(o
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-5-April 1, 1998 Attachment A - Calculations
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Determination of Nitrogen Loading
from 168 lndividual Sewage Treatment Systems,
Los Amigos Ranch P.U.D., Filings 6 - 10
3. Method 2.
1 . Low end groundwater loading of O.782 mg/lit.
2.tz 17 - /- g{rL t o'1Sn3t,-
2. High end groundwater loading of 2-28 mg/it
O- 8? ,*T
--..
-'( -t
(q 'ztL)(ff)" u 0{"*t 0'2!ft'*YtTif I
/ Z-/2 t,*\ t. o n*? o (/. 9{ t * )(0:u nl\ ' '-L,7 )\77"
/'t*r
/J2.t?tL + /,?{tn t o' 3{L16tu
Nitrogen loading to groundwater without Los Amigos ISDS systems. This
inctudes only teakage from Spring Valley and precipitation infiltration from
Los Amigos.
9? ^-t
-/,t-
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Z.r?tL L /.9{r',-
lncrease in groundwater nitrogen loading as a result of Los Amigos ISDS.
t. Lo - fZ.-r' /1€ : b .
-- ), €3 t( l*L
-/.:t
-O,{3?p?--0,3{bry7-'"-a
z.llt</ 2rH4Et
1, 1 998
0,si1 ry.+, /.3#
77+,(.; t
lTqr*Ltd
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April Attachment A - Calculations *
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Determination of Nitrogen Loading
from 168 lndividual Sewage Treatment Systems,
Los Amigos Ranch P.U.D., Filings 6 - 10
6. Nitrate Concentrations in public water system drinking supplies located in
the vicinity of County Road 114 and Hwy 82.
. Mid Valley Mart, lnc.
1. Low: 1.50 mg/lit
2. High: 3.56 mg/lit
. Mountain Meadows
1. Low: 0.90 mg/lit
2. High: 1.83 mg/lit
o HLazyFMHP
1. Low: Not Detected
2. High: 1.29 mg/lit
o Sopris Restaurant
1. Low: O.0O mg/lit
. Well Permit #046017-F (Collins Drilling, Co. Not a public water
system. Analysis with Hach color disk on March 3, 1998)
1. Low: not detected
. Average of 8 samples listed above: 1.14 mg/lit
7. lncreased nitrate concentrations in vicinity of County Road 114 and Hwy 82
as a result of Los Amigos ISDS assuming that presently 50% of the
groundwater flow comes from the direction of Los Amigos and 50% comes
from other sources.
o Determination of nitrate concentration in "other sources"
= l-14 *1fl,t
X- = /-?(A '*f
-L;t
April 1, 1998 -7- AttachmentA - Calculations
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Determination of Nitrogen Loading
from 168 lndividual Sewage Treatment Systems,
Los Amigos Ranch P.U.D., Filings 6 - 10
Determination of range of increased nitrate level resulting from Los
Amigos ISDS.
1. Low range (GW loading from Los Amigos = 0.89 mg/lit)
a
L?:Lz. tzt /- e f ) r o- 3{ Ll 9-
= /-3o ,w1
l;t
= 1.74 mgilit)
/ -? qo)
2. High Range (GW loading from Los Amigos
(z.rz * /- 9{+ c-/ iz':t{t'tr) n ("-t?+/ 0
^(
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Lz I (2. t2? /- e{) + r'- t 32?
Change in nitrate concentration as a result of Los Ami$os ISDS
1. Low Range
/.i ry- //r/
@- "'t
High Range
/ 7::? -.> t./l 0. bo '*a
ffi--
r-+d-
/it
-8-
: /-7zf ry
4'--
c. /b ^,-5
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April 1, 1998 Attachment A - Calculations
8.
Determination of Nitrogen Loading
from 168 tndividual Sewage Treatment Systems,
Los Amigos Ranch P.U.D., Filings 6 - 10
Conclusions
o Recommendations
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ISDS systems in Los Amigos P.U.D. may increase nitrate levels in
groundwater in the vicinity of County Road 1 14 and Hwy 82 between
0.16 mg/lit and 0.60 mg/lit.
Existing groundwater nitrate levels in the vicinity of County Road 1 14
and Hwy 82 range from 0.0 mg/lit to 3.56 mg/lit. These are well
below the drinking water standards established by the EPA and the
State of Colorado.
Properly designed and maintained tSDS systems in Los Amigos P.U.D.
wilt result in no drinkino water contaminant concerns in the vicinity of
County Road 1 14 and Hwy 82 or elsewhere along the Roaring Fork
River.
High quality ISDS systems should be required.
1.
2.
3.
Trench construction for leach fields is preferable over bed
construction.
Septic tank efftuent filters should be required.
Leach field dosing systems from septic tanks should be
required (as opposed to continuous feed from septic tanks).
1.
2.
3.
An ISDS management plan should implemented.
Operated under the authority of the homeowners association.
Annual inspections required.
lnspections made individuals trained in the operation of lsDS
systems.
-9-April 1, 1998 Attachment A - Calculations
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ATTACHMENT C
METHODOLOGY TO PREDICT NITROGEN
LOADING FROM CONV. GRAVITY
ON-SITE WW TREATMENT SYSTEMS
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Methodology to Predict Nitrogen
Loading from Conv. Gravity
On-Site WW Treatment SYstems
WWBLREl4
Thomas Long
1 995
This product is funded by the United States Environmental Protection
. Agency. The contents of this product do not necessarily reflect the
views and policies of the Environmental Protection Agency, nor does
the mention of trade names or commercial products constitute
endorsement or recommendation for use.
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Methodology to Predict Nitrogen Loading
from
On-site Sewage Treatment Systems
Tom Long (1)
Backeround
This docr:ment is intended 1s improve r:nderstanding of nitogga 6ensfsrmations that occur as
wa.stewater is zubjected to on-site sew€e treament It describes factors that affect removal
which wtll heip designers and operators Euximize performance. it aiso provides a method to
esrimate total nitroggn lssriing that utiiizes soil characteristics and site descriptions described
on q?ical permit appiications. This information can improve the accuracy of gror:ndwater
impact predicrion.
On-site svsrems provide wasewater treamert for approximately one third of the population in
$y-35hington State. These s-vsrenrs originated by necessiry in rural areas. and continue to
provide Eeatment f61 many sparsel-"- deveioped and r:nincorporated areas that tend to be
iocated in areas where groundwater is adversely affected by agricuinrrat activiry. lu areas of
higher population densiry. use of la*n fenilizers and other contaminants compor.rnd the
difficuitv of determining gror:nd'*'arer impact. In iight of these problems, rather than base
performance expectations on gror.nciwarer snrdies, this investigation appiies niuogen
mee^surements from vadose soil beneath Eeatment s-ystems, gslrrmn snrdies, and soil fiiter
s.vsterns.
Understanding the Septic Tank
Process Desciotion
Sewage of varying stength is carried by water saturated with free oxygen &om the dwelling
directly into a septic tank Se*'age flow is interminent, and cyciic in direct response to water
consumption patterns of dweiling inhabitanu. The septic tank is designed to provide neariy
ideal plug flow quiescent settling conditions for approximxely 7 to 9 days.
During this time, materials with specific gravities both heavier and lighter than water are
removed from the wasre sEeam by physical separation. Lighter materials. such as paper and
grease, are retained by a baffle wall to create a scum layer. Settleabie solids, which include
grit and organic material, drop to tbe bottom of the chamber and are digested by anaerobic
mesophilic bacteria Most anaerobic digestion activity occurs at the top of the sludge as it
accumulates, so active gas production does not cause sludge turaover. This phenomenon has
been ideotified by limnetic studies in lakes with no seasonal variation. The accr:muiated scum
layer, and anaerobic digested sludge is periodically drawn from the tank for ultimate disposal
as septage biosolids.
Since domestic sewage tavels very little distance before entering the tanl! incoming flow is
ofteu saturated with dissolved ox,vgen depending upon its temperanre. This keeps the liquid
fraction of the tank coutents freslf which Promotes settling. Since Eany bacteria adhere to
particulate matter that seule to the bottom, minimal nricrobial activity occurs in the upper
Liquid portion- (J) Tbonas Loag 269Westaltcr Meaegeurcnt SPccidist
lYrshinglou Satc Depertncut of Eceltha
Septic Tank Removal and Immobilization of Nilroq.e'.n
Septic tanks are onen perceived as u pr=ffi-*liule of removing niuogen' It has been
assumed that these sy$eEs merely convert all nirrogen 16 amrnsaia However' evalnation of
national s rvey a"t',rai*,ed that s"Plc tanks remove a significant portiotr of D'itrogeu from
the domestic \r'aste sEre2rn. An e>censrve data survey was conducted by the U'S'
Environmenoi pror..-J* Agency to derermine r,vpicar roading parartrerers for wase treatment
design. Resr:ls reponed by the "ry.I in EPA-600/2'2'78-173 are significant to this
ravesrigarion since ,i. t.p,ia provrded septic 1,nk inlluent and effluent total nirogen
concenuarions. The data indicate tuat toral nirogea i:rfluent couceutratiotr ranges betweeu 36
to 94 mg,rl-, and the efflueut concenration t ngei between 26 to 76 ,'g,!T'' Calculating
niuogen removar *i"g *ri, ,i"rmation re"eaii that rpical sepic talks retrlove berween 24%
alraigw of total ninogen from the appiied *'aste strean'
Process Desciotion
Microbial li6fiims are in-srru,,enral in uearing septic tank effluent Biofilms thrive uncier
eirher aerobic or anaerobic conditions in a wi-ci: rauge of environsreots (Auciic i984)' The
cl.clic uan'e of domesric \*'arer consumption esrabiishes alternating aerobic-anoxic conditions
i<nown to encourag. G. go*ru of facuitative bacteria capabre of sr:rviving either conditioo
(Anther:nis* 1gg7. So.rJ, 1gg1. pell 1991). Biofiims bave been rescarcbed e>censiveil'and
numerous preciiction eqr:arions are available to estimate activir,r- r:nder variotls conditions
(charackii; 19g2. iiarris 1970. Mo* eqr:adons arc a firnction of ex.oon[. arce- temperature'
pH. fio*.rare. and zubrate availabiiir,"*. ide:J conditions for biofii:a forrnation is zero to
lentie fiuid flou' ,*rth a ncb subsrate (Charackiis 1973).
Fuli niu-ificarion occurs u,hen the portion of nirifier biomass rtrean cell rcsidence time
(MCRT) "ppro*n.ili ,o 30 dayi (Fiartiey 1985). Full nirificatioD, nsc€sssr-v for zubsequent
denirificatior:, *iti contbue if a-srfficieniponion 9f the biomass i5 maintaiaed within an
aerobic environmeoiGpe B7n. Deniaifier population growtb is much faster than niriirers,
so time required to reach stea.dy stare is li'oi,"d 6 nitrifier growrh dyoamics. optimum
pr:rifving efficieocy i, oft+lj aftcr about 6 weeks of opcration, but bactlria cootinue to
increase in n,mber for anothcr 3-7 weeks before reaching ecoiogical steady state conditions'
(Pell 1991)
The soil Eeatment process, and performance is equivaleut to tbat for:nd in sand filters and
packed bed bioirlm-rea.stors co--only uscd by &e wasrcwarcr indusry @ouwer 1987)'
variations in species dsminan66 througbout tht sysrem rcflect the diffmnt physical
environments and zubsrrares which *J* @ell lggl). A-E enumerarion of organisms
conducted by the virginia warer Resources Cester found oitifiers ou tbe gravel surfaces in
the disributioo sy$cm, and repongd thur the highes denitrificr population was found at the
gravevsoil iot.rr*" @"g.o rger;. This is to be expected sincabiofri:ns on the gravel
surfaces *. .o*riy Jxposea to armospheric orygen- Thosc u tbe soil interface asd below
are zubject.a to at.Ltioi aerobidanoxic elnronmeurs, thrs e'couragilg the prcdominance
of facultatir. uiorrils iyLr*a selection. Facultative microbial activity resrlting from
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altenrating periods of flooding and drying has been fonnd to remove 30Yo of appiied nirogen
(Lance 1977). Reducing hydraulic loading rate down from 50 to l0 cm/day increased
nirogen losses from l0% to 80% (Gilbe:t 1979).
Distribution Svstem
The liquid fraction or effiueut passing from the septic tank contains sr:spended organic soiids,
facultative bacteria and dissolved salts. Bacterial respiration causes lowlr (anoxic) or depieted
(anaerobic) dissolved oxygen conceutation (Grady 1975). The effiuetrr flows to a subsr:rface
perforated pipe-work distribution s,vstem within tenches back-filled with gravel to create a
ventilated void. Upon reaching perforations, effluent intermittently flows over gravel in the
void space- Bacteria in the effluent muitiply upon contact with attachmeut surfaces and creare
liefilms (Audic 1984). Microorga''isms, organic debris, and polysaccharides accrrmuiare ar
the interface surface. forming a nanral fiiter called a biomat withh 2l days (Okubo 1983,
Nilsson 1990). Microslraining by this "fllter skin" removes over 90Yo oi the BOD. and
suspended soiids. Over 99Yo of the bacteria are also removed (Ellis 1987)- The biomar
restricts percolation, cansing temporary ponding with each hydraulic dose period (llourion
1987). Each dosing episode must wet rhe entire biomat, which acts iike a sponge rescins on a
Porous surface; it mr:st be completely satr:rated before releasing liquid (Gardner 1968).
Berween dosing episodes, effluent seeps through the biomat until the layer is ,gain exposed.
thr:s complering a cycle.
Before ox-vgen can be r:sed for celluiar respiration by microbes, ir musr be dissolved inro
Iiquid films s:(pssed to the aorosphere. The atmospheric orygen supply to the void soace
resuits from direct continuiry throug! a pipe ven! and ind.irectly throug! 6 inches of soii
cover. To reach soil regions beiow the infiltrative surface, ox,vgen must pass throush much
more soil voiume since it Inust travel from either side of ttre uench s.vstern. Gas tansfer to
passive iiquid surfaces is reiatively inefficient. Therefore, dr.ring "ponrling" periods. nurients
are available but microorga''isms mu.st compete for limited zubsrate ox,vgen. The situarion
aiters during periods when moist biofilm sr:rfaces axe exposed to the atmosphere. Even
though oxygen transfer improves, microorganiil[s must then compete for subsrate nutrients.
Unsaruraftd Zone
After passing through the clogging layer at the infilnative surface, atmospheric oxygen is
agai! available to zupply necessary metaboiism requirements. System aesig! requiris that
eftluent flow through at least three feet of unsaturated soil called the vadose zone before
reaching groundwater. hdividuai soil particles.in the vadose zone become coated with
biofiim called "micro-sites" since they exhibit all the characteristics of uormal biofiLns, but oD
a smaller scale (SanreriDski 1986, Revesbech eL al. 1989). The bacterial cells produce
gelatinor:s entacellular polysaccharides on the sand particles and as a consequence. reduce the
pore volrrme by about 0.1 -0.7o/o. This increases contact time benveen the water and the
surface of the sand particles, and resticts oxygen tansfer @etl l99l). Not only is oxygetr
transfer to organi565 within each biofiim resticted, but void space sanrration dr:ring -""sflow episodes intermittently limits dissoived oxygen to the entire biomass (Rituann 1983).
This establishes conditions tbat are conducive to biological denitrification
Liquid movement through uDsaturated soil is much slower thnn &ysugh an equivalent
saturated soil. This extended tavel time assures contaminant atrition Bacterial atridon
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occurs as decreasing carbohy&ue availability forces ruore conpetitiou, and bacrcna fall preyto grazier organisms tbat prifer consisteut aerobic conditions. ru. uoitu."t.a vadose regionalso removes volatile zubiunces &om the efflueut In accordao." *itn-gl laws. voiatilegases are displaced &om solution bv gases generated during nicrobiai Jiboiis. Thephysical turbuience of flow cascad"ing or., !rrti.l. surfaces assists the rate of traosfer moreeffectively than lulfle aeradon (lvlulter i98l). As nirogen gas and volatile gas€s aresripped from solution' the;r eveurnaliy pass from the soii-srudce iuto the Losplere.
Fiucrr:adng water tables are cond.ucive to biologicai denirification (l.lilsson lgg0). Thiscondition is often recognized in fine texn:red, soils and uear wetland areas. However. ifcompiete nirification is uot aszured qrfrhin the soil process, groundwarer may becomecont'min2ted by ammonia or carbouaceous co,lpo,nds.
---' E v-$'r$'w' ur
nlptqstcdl Nttrlflca
Nirification is the formadon of No2 and No3 from reduced N by obligate chemoiirhou.ooiricbacteria which use inorganic niuogen compounds ro supply tneir energy=;;. 6;-j;;""'"'compor:nds including carbon dioxide (Co2) are rrsed for ceiluiar q^ui.ri, reactions bur aorenergy producing reactions- Dissolved ox-vgm serves as a terninai eiecton accepror dr:ringthe reaction' The rwo major genem of bactiria responsibie are .vl'rzoso monas aod, Nirrobacrer@rock 1988)' Ni,osomorrd,s use the energy derived from rhe oxidation sf ammsnia rllH4) ronirirc OIo2)' The MnoDacter are then able to deive eaerry by reducing nirire rlio2):onirate C{o3) for cellular qmthesis. Both of these nirifiers prer'er a pH above 6. Sincenirification consu'roes aikaliniry as hydrogen ions are reieasecl rhe pH drops slighriy. If :heenvironment is too acidic for Nitrosimonas and, Nirrobacter. heterorophic'niu-rfrers such asfungi that prefer lower pH wiil preciominate. As long as carbon, and d]ssolved, orygen areavailabie' aidfication will .ooG,r., though not as erTertiveiy. in rpicai on-site s.vsrems.o4vgen availabiliry is the subsrate ,ort .fr."ting nirifrer activiry.
-'
Biologicai denitrificatioo is th. t"duction of oirogea oxides to a giiseous form b;z facultariveanaerobic bacteria tbat r:se molecular oxygen as a rerurirul ."."p,i, 1lr til;*nce of freeoxygen' For denitificltion to occur, the bacteria ruu$ be avaiiable, wirh thc prescuce ofelecuon donors in the.fornr of orgaaic carbon, hydrogen or reduced suifu. The proponioo ofbacteria with deniri$q-"+."iri raoges benreen 0.j and Looyo, with the highest perceilages .found at steady stag Pgit f ief ;. Total organic carbon co--only considered the limitingsubsuare for denitrification in the nnsan:rated zone. has been detectra
"t a.ptts 2 feet belowthe infiiu'ative nrrface.in coarsc grained *ilr fii"r-- igqrl. They m*st also be inconditions of limited SYly.a orryg.o with a source of oiuogen oxides *.n ., No3, No2,No' or N2o' The deniui@s orgrli.." use Noi errr, p-aucing No2, then svitch to No2as No3 becomes limited., Since 6e reduction of nitrire (No2) is believed to involve niuor:sacid' decomposition is favored under increasingly acid conditions. Acid conditions occur oEclay and organic Eurtter srrfaces which can beless rhan gg averagc;;; soil pH. ThepH at particle surfaces, 41d ,slirhin the biofilm is lower than that measrned in &e buik flowsince alkaiiaity concentation is depressed by nirification (Sarerinski 19g6).
Denitification not only occnrs is aneelslic soil condirious but in well aerated soit cond.itionsas anaerobic microsites develop when respiratioa rates exceed orygen aim:sion tbrough fig
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soii. This phenornenotr h:s ls€s observed ia packed fiircr reactors and aerobic soils. It is
responsible for up to 4lYo airogen removal from siow sand filten rearing second ,v effluent
(Ellis 1985). Sand filters teating prinary effiuent average 60% nitogeu removal (Mancei).
Micro-site activiry is aiso credited u'ith over 35% nirogeu rcmoval beoeath eonvenrional
s,v$elDs (R.iner and Eastburn 1988). Nan:ral denirification losses raogrng froa25o/o to 35%
occur in pasrr-ral soii seaings that could be considered equivaient rc conditions found i! manv
home lawns (Hauck 1971). Finer grained soils achieve grearcr denirification due to zubsu.are
exPosure to larger biofiLm sr.rrface area per unit volume and resricrcd dralDage through
smaller pore spaces thar sauare readily @otrma 1975, otis and Boyle 1976).
All the components necessary for effi.cient denifficatiou are present in the soil coiuma-
How'ever, in some profiles spadai separation bewreen the oirifving zoBe and potential
denirit-ving components is more pronor:nced (Peil i991). ln these siruadons, denitrificadon is
Iower. This sitnation occurs if the organic materiai is degraded. 3sd ammsnia is oxidized
raoidly r.1,'ithin the top 10 cm of the soil horizon- Once the cariron is fuIiy oddized anci no
regions of limils6 oqvgen availabiiiry exist then there is linie chance for nirogen reduction.
This situation wouid describe the aerobic conditions rl,.ithin deep, venr coarse grained soiis.
Factorc A-ffectine Consistent Biolosicdl Nitroeen Removal
Technical simpliciq' and domestic loading characteriscics favor a consisrent niuogen reraoval
performance by on-site sy$eros. in the activared siucige Drocess borh the waflewarer
composition and rhe forced aerobic environment dkect bacteriai evoiution toward a few
speciaiists. The iniiitration s-)-sten consrinrtes a urore variabie enl.ironment therefoJg ssatains
a more diverse popuiation, including several species capable of performing rhe same
processes. if toxic conciitions caused a soecies to bc eliminate{ rhis diveniry aiiows the
degrading capaciry of the rcrneining orgenism5 ro compensap ior tle ioss. ln the same
siruadon, efrectiveness of an activateci slucige piant wouid most iikely 'oe eliminatei Peil
1991). However. the inriitrarive sr/stem mr:st be propcrly designed, ilstalled and operareC io
minimizs the possibiliw of zubjecting the bacterial colony ro arivere conciitiors.
En'riron-o:ental conditions that affect nirogen removal performance are discr:ssed in detaii
below.
(1) Nutrient availabilitv
Since the wastes originate from a singie domestic source, subsratc nutrients are avaiiable in
relatively predictable qr:antities and cycies. Normal dwelling occupancy or lifesr.vle shanges
cause gradual changes to nurrient Isading.
However, a nuEient overload episode to the soil s.vstem can be car:sed by septic siudge
overfl.ow if tank pumping is aegiected or the sedimeatation process is short-circuited. A
combination of nurient-rich substrate and insufficient orygen will etrcourage filamentous
microbiai growth (Wiliiams 1989, Tanaka 1985, Okubo ig8:l This is duelo narurai selection
since the filamentor:s shape exposes a larger cell wall sr:rface area to the limircd o4vgen
zubmate. Under persistent conditions, filameurs and polysaccharide bridging benreen soil
particles eventually retard all water Eovemeut Once the hydraulic load lxceeds the
percolation rate, sewage either backs up into the dwelling, or effiueut appcars at the gror:nd
sr:rface. Sr:rfacing sewage potentially risks public health through parhogen cotrtact Rourine
pumPing Progr:uns can reduce the potential for tank faiirue. Proper design should aiways
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accurately ztsscss futr:re sewage strengrb aod plan accordingiy'
fl"TTrTTfl:i to accept and retrarsmir hear a[ows for efrective bufrering of remperanue
variadons in rhe effluent before it ,.u"Ltt the soil absorptiou syste.' Seasonai temperarure
changes speed "p *Jrfors,, dswn Uiotoglcai activiry in upper soii horizons' Propell' desig::eci
domesric s,v$ems are not expected to bI adverseiy affectxi by teEcDerature'
fl.lii:H: risk of bacterial desiccation si-oce rhe *-$em is instailed beiow the soii suriace-
Hydrauiicloadis"or-arypredictablefollowiaganinrcrmirtetrtorcvclicPanern;hor'r'ever'
coD$ant hydrauiic flow dus to leaicy pir:mbing f'rnrres' or excessive water use can cle3te a
constantly ponded .mr.o, sinradon in the ciiiribuuon void (Okr:bo 1983)' This can eiiminate
inrerminent oxygm tra:rsfer to nitrifiers withilx &e disrrbution Sy$eB' Since bioiogcai
denirificatiooira"p.oa.otuponnitrifieractiviry't)-$emnerforrrl:"-:lt*trtt
Flomeowuer education regarding poteodai effec6 of excsss w'ater cons:mption cag ?rolnote
s.vstem longeviry and consistent performance'
(4) or-vgen . --.-:-: -^--i-;inn .uinrp
=
Ntost of rhe ciissoived ox.vgen is consumed by microb.iai respiration irefore efrluent tt:::::^l'
subsr:rface soil s.vstem. Condnuor.rs subscrare o'eraboiism is deperdert upon o6/get Eansie:
ro effluent'as it passes through,n. q'"t- (Siegnst i98s)' orys:111':-"ili.5;iatei:-
alTects bioiogicai p.".r..t ia .- te identifred by s1s:ni51s enrrnerauon in var:'olls
treal[teot process regions. As dissoiveri ox,vgee'oeccmes depierecl denirifrer species 'eccme
predomin:''r ir moieiuia, oxygen is avaiiabL-@egea 199I)' It sands io resson "hen"jrat
under cons13nt hydrauiic flow regimes the mrnryilg species must esabiish upsu'e"m oI
denitrifier organisms. However, .ooo^iiy.i*rii"-ao* does not exist in most of the on-sire
s,v$ems. In these regions, facuitative spe"itt t"ttye *te seiection process ciue to tbelr
caoabiiir.v ro me,ubo1-;" either dissoive<i or moiecuiar oryge' acccrd'ing- to the stress io *'hica
they are subjected- ln biofilms thar form in aerobic condidons' cienrrifrer species beccme
physicallyseiefiedinthefiimbcuealhthenirifrers(Suznd1985).
The amor:nr of dissolved ox,vgetr $ar can be enuailed in waEr is a firnction of temperilnue
and qr:antity of gascs already **6J in soiution The ox,vgen mesfer rale to rxzter is
affected by the a'ouil of t,rbuient ;e appiial Trubuience dispiaces encained gases
consrantly by exposing the liquid oofr". io thi amospirere' Gas cransfer is rescricted by
sarurated o, .o-!*G *ilr. ^ origlnai sy$em design and iutaltation can asstrrc thar gas
transfer is not restricted, but proper "pt''io" p'otJti*tt mr:st be followed to inst'e that
physical conditions do oot deteriorate'
sJI*. wa$ewater and scptic tank effiuent pH is relarivery consranl. Nitrificadon reduces
alkalinity slightly, but not outside the favorabi. *g" for facultative oiqoorganisoas'
However, if d;;;;"ii.-rrrag, digesriou Ersr stage voratile acid production exceeds
second stage methane generatio" - G=r.p.i-Jorr it ii possible-fgr a septic tank to nsor''"
If this occurs, ""ffi;d:.'.,Ioffiiilnt
pit can becom" o'idi". whiie some facuitative frm* in
the disrriburi., ;;;i";;conaitioas as low as pH 4, rapid and wide pH fluctuations are
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not conducive to nirifier popuiation srabiiiry. This sirr:ation can deveiop in a septic tank as a
resuit of excess organic lesding, or if toxic conditions are introduced which affect the baiance
benneen first and cecond stase anaerobic digestion @PA 1976). The first siruatiou causes
rapid first stage bacrerial growtb- incapabie of being matched by second stage digesion. The
second siruation resuits from microbial mortalir.v that causes undigesed organis material to
buiid up. Since the volatiie acid formers reestabiish first, and much faser than the secoud
srage. volatile acid concenrration rises rapidly as if excess organic ioadi:lg occurred. Acid
condirions are trot expected to occur in normai domestic septic s.vstems since toxic zubstances
are not ordinarilv dis-oosed in domesric se\,r'age. However, sink garbage disposals can possibll'
cause extreme organig i6ariing especiaily dr:ring home canning operations, therefore their r:se
should be discor:raged.
Other Nitrogen Convercion Processes Occurring In Soil
Porentiai nirogen removal can also occur dr:ring soii rearnent potentially tbrough Processes
other than bioiogical niriJication,'denirificarion. These processes and assr:med reiadonship
to on-site s.vstems is describeci belo'*';
(l) Immobilization
Soii microorganisms that conven inelsanis niuogen to the organic state couid retaia some
nirogen by uptake wirhin the biomass. If sufficient orgenis carbon is avaiiabie as an energ,v--
source. some uiuoeen is immobilized wifiin the cells. However. the iow carbon to airogen
ratio in septic eflluenr limia niuogen rercntion so excess nitrogen is released from the cells as
NH4. This process piays a minor roie in niuogen removal for on-site s.vstems.
(2) Mineralization
Minerelization of NH4 by adsorption onto clay, and./or organis parricles is a fi:nction of soii
pH. Acid soiis favor adsorption onto clay, and aikaline conditious favor adsorption onto
organic particles. This is limired by ions that are competing for available adsorption sites.
Research by Ho et.al 1991, recorded 45oh removal of apptied nitogen from primary effluent
in coarse sands amended with 30% red mud, a bauxite ref:ning rcsidue. Removal was
amibuted to increased cation sxghangc capacitv tbat increased amm6fis6 adsorption. The
adsorbed ammonium was then nitifred and denitrified during alternate flooding and dqving
cycles.
(3) Volatilization
Ammonia voiatiiization depends upon pH and temperanue of the soiution. NH4 volatilizes to
NH3 as a function of pH. Formation of NH3 increases with higher pH (7 to 9). Higher
temperanre aiso promores rapid volatiiization. The rate of volatilization is hampered by the
distance NH3 gas must Eavel before being lost to the aurosphere. The oitrification Process
consumes alkalinity, therefore conventional on-site slstems are unlikely to raise the pH
zuffrcieutiy to cause volatilization. This is uot considered a major removal Eechanism.
However, this may be a factor to be corsidered in waruq highiy alkaline soil regions.
(4) Chemical Decomposition
Chemical decomposition of nitrite (NO2) can occur abiotically through a reaction with organic
matter to forsr gaseous nitogen. This can occur where Nitrosomonas produce NO2 faSer
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than Mno bacrer can converr NO2 to NO3. This could occur if a high pH (9) caused the
release of ammonia rhrough volatilization since Nitrobacter are very scnsitive to the toxic
nanre of free NH3. A hi-gh conceusatioo of NO3 favors NO2 accusrulation and its
subsequent reaction wirh organic mateial, bur this removai 6sshrni56 is probably negiigibie
in on-iite s.v$ems since the oppornrnir,v for voiatilization is low'
(5) Plant Uptake
irt*t up,rte of niuogen, or g'anspiration, can occur if nitification occtus high enough in tbe
soil profiie to be reacheci by piant roots. Significant plant uptake was demonsrated rsrng
Common Bennuda gftIss over Prolorype on-iit" s.vstems- Up to 460/o o-f the applied niuogen
(19a kg Nrha) ** ,-.-oued by opt^i. from on-site systegs over slowiy permeable soiis
igro;; l9i8i. The erfective uptake was attributed to pond,ing which kept nitratg within the
root zore. This phenometron is expected to occur in areas with fluctr:ating high water tabies'
or high ciay contenr. Nurient uptake and storage by hardwoods in wetlands appears to be
insignificant (Ehrenfeid 1 986).
Wtriie vegetation at narr:raily occr:rring densities on sandy soil does not have significant efrec:
on waler qualiry, augmenting appropriate uaturai vegetarion with zuppiemenury ree olanrings
can reiuce nitogen movelpent to grogndwater from septic systems in sand-v soii (Ehrenteici
1987). To efrectiveiy renove niuogen, they mr:st bave deep taProots an-d be planted'*ithin 3
feet of the diribution renches. Nirogen upake by pine ranges from 45_ to 56 kg )i hatp
whiie uprake by oak ranges from 55 ,o Og LL N ha'yr. Vegearion h *9 range lan<i cioes aot
demonscarc rapid nurieit upake unless moi-mre is aiso avaiiabie with the nutrienrs'
therefore, piants mu$ be near the renches to be effective. Brukhardt (1993)'
Once niuogen reaches grorxrd'*'arer, vegetation is capabie of remediaring relatively high
nirogen concegEario*. R.r"archers "i th" Grear Plain<-Rocky Mor:ntain-Hazardotts
Substances Reseerch Ceuter (HSRC) have confirmed thar vegetation, specifically popiar rees
(popuirs spp.) can prevetrr herbicides, pesticides anci feniiizers from contamiffItitrg sr:rl'ace
and gror:ndwater. At au agilcuitural t& site on an Iowa farm. a 3-year old poplar Top lb:at
were pianted berween a strean and a comfieid reciuced nitrate-nitrogen levels in leachate from
fenilized fields. Niuarc contetrt in groundwater at a point beseeu the field and a
downgradent sEealn was reduced frJm 150 mgll- dowu to 8 mg/L' Nitate was fi:rther
reduced, to 3 mg/L ar the strean bank Poplar rees were choseo because they take up soluble '
inorganic nitogen and ammooir:m-nitrog"o,troogh their roots, covert nirates into protein and
niuo-gen gas. en"t five growing ,"rro*, the average ree conrains 33 g of organic niuogeu
in itsstem. (Warer Enviro''ment TechnologT June 1994)
(Q Evaporation
If effiueut containing nitrate evaporates in the vadose zone before reaching groundwater,
nicare salts are formed. Since nitate is o,egatively charged, it combines with positively
charged ions also in soiution. Commonly ivailable positively charged ions are us:aiiy
caicigm, magnesir:m, oI potassillm. Upoo evaporarion, the salt becomes geologicail.V $ea
and persists ,:ntil soi .oirorr" again reaches 100% saturation and can re-mobilize the nitrate'
This sinration can only occur in iegional climatic senings where evapo-traDspiration-potendai
exceeds annual rainfall, and artificial recharge by irrigation is not being practiced (J'S' Dept'
of Agriculttue 1969J. i,lo aitogen is expected to reach the gror:ndwater under these
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coaciitions. These regions are identifiable on maps as sait or atkaline prone soils. They can
also be identified by iocal veqetation thar has adapted to survival in these resions. The
characterisd. ,.n.o.ion wili i. *.ro;i1*i.;;t;;phn.i","i*". a.ir.i*, a-=rrn.
roieranr).
Physicai soil moisnue mea.flrement becomes increasingiy d.ifficuit with depth. but the salt
accumuiarion resuiting from periodic evaporation episodes is more easiiy identified (Geyer
1992). Chemicai saits form at a soii texrurai chanle point within the vadose zotre. Salt
accumuiation occurs at these poinrs when mauix forcis in fine materiai overcome tbe
grariutioaai influence iong enougfi for evaporation to occur (-r.S. Dept. of Agriculture 1969).
This condiriou is identifiabie in arid regions not under irrigarion as seasonaiil' perched w'ater
thar evaporares dr:ring dry peiods.
C o nventional Effl uent D istrib utio n Syst em p erformance
For man;- vears. it was assr:meci rhat no niuogen was removed above or *irhin the biomar-
and ihar once airificarion occurreci q,'irhin the unsaturated zone beneath the inrlltrarive
surface. insuf;icient carbon 'was a'aiiable for denirificarion.
Howe"'er. not cuil' have niujfr::g sJgani5ms have been detected in the aerobic voici zone. but
enumerarion mrciies rDegen i991) found that the iargest concenradon of facuiradve
orgarrisms accumulareci wirhin ihe biomar If nitificarion is not occurring either upsrream. or
l'tuitaneousiy' at this region, then they would not be nanraily seiected. This r*'ould account
for some nirifrcatioo and deairificatiou. The exposure area of effluent to slirne or biomass
ia this area is expected ,o 6s limired in comparison to that of the micro-sites in the
unsanrrated zone, so most of rhe bioiogicai process is expected to occur below the infiiu'adve
surface.
Potentiai nitrificadon and denirification in the unsarr:rated zone is d.ependent upon periods of
restricted gas E:nsfss. Orygen rnusr move through the void space beween grai::s of
unsarurated soil to reach each micro-sire during periods when bulk flow is not occr::ring.
Logic then lea.is to the conclusion that biologilat aeniUncation potential is related to the size
aad disribution of soil particles. A fine grained soil wiil have small voids betwr-n pa:ticies.
This will also be fouad in soiis with a higb uniformiry coefficieat (mi:rnre of sizes). These
soils will tend to stay sanrrated longer during bulk flow periods, thr.rs restricting gas flow.
Untfgra:" coarse grained soii below an infiltation zone pronotes a region with a potential for
rapid niuogen oxidation. After the carbohydrate suppll is exhar:sted, biologicai dlenitrificadon
is less likely unless additional carbon becomes avaiiaUte "downsteam" in a separate anoxic
spatiai region.
An estimated 40% to 50Yo of the total nirogen is removed by conventional on-site syst€Es
(Laak 1986). Before accepting estimates however, this investigation bas anempted. to confirrr
them with fieid measiuement and to identify situations which carse variatiou.
o
IIe 277
a
a
a
a
The most accurate evaluation compares infiuent with effluent data collected from confiner
flow poinrs (influent & effluenr). This is possible for the septic tank and sand fiiters sinc
flow is easiiy ac:essible. Interminenr sand fiiters have ccnciilisns 5imilar to hycirauiic ioa
and soil beneath on-site s-v$ems. If one is to assume that performance of the soii beiow .
on-site s.vsten is comparable to a sand fiiter, 40o/o n 60% otai niaogen couid be remove,
from the effluent by soil reametrt (rVfancl 1991).
Field measr:rements beneath the soii of a convenrionai s-vstem are much harcier to conciuc:
and hydrologic groundrvarer snrdies are afrected by nr:nerous factors that compiicare ciara
evaluation. To minimize the factors associarcd with gror:ndwater sn:ciies. this eval:adon
concentated on nitogen mea.$rements coilected in ',tre vadose resion benearh the in-frlu'a.
surface of acdve on-sire Eearment s-vsterns. The data was conveneC to total niuogen for
evaluation. This was necsssarJ' because nirogen exists ia several moiecuiar forms. Daia
from snrdies that measureC nitrogen in all ia tbrms at various depths beiow s.vstems is
presented beiow. Unaccounted nirogen iosses are assumed to be the resuit of bioiogicai
processes since mineralizarion is expected to be minor. J[g data indicates thar soii u,earrr
rprnnvps henveen 1i0l^ tn 1000/n nf the qfrfrlied nirngen
Nitrogen Removal Measurements in SoiI Beneath
Conventional Eflluent Distribution On-Site Sewage Tregnnent Systems
M. Dege.'. R Reneau Jr.. C. Hagedom- D. lfarcina
Virginia Water Resources Research Ceater (1991)
Measurements'*ere based on lirous oxicie sxxmission from 'he soii :o :he atrnos^c
This data indicares a 17Yo nitrogen reiuction aner passing through -15 trcnes of sc
below the infilrative surface.
o
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..
)
DEPTH
(Beneath infilnative surface)
0 inches
15 Inches
30 lnches
45 lnches
TN t'me4(erqm dr.' soil)
lback grounci subtracled)
346
39
116
i84
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278
o
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o
o
o
o
o
o
;a
o
a
K.M. Shermae D.L. Anderson
Fiorida Deparurent of Health
A1"res & .{ssoc. 1991
lvleasrued volarile slsanig compouncis and conventionai paramercrs
-b-v
coilecting soii
sarnple cores from bJneath *d *ii"..nt to active on-site s,v$en infiitrative zurfaces'
Ail VOC was complereiy re,or.d b.for. or immediateiy after pTTgt througb the
infiitralive sgrface. Toul organic carbon was Ineasured down to 2 feet below the
infrifative sr:rface. Toal ninogen daa ha-< been adjnsted bv subtracting the
concenuation measured in borel adjacent the d'is.oosal area This dau indicates that rhe
on-site s.vsrem not only esabiished cond.itions rhat removed ati nitrogen appiied ro the
on-site ,-u*.- uur ato reduced nitrogeu leaching from the soil surface'
DEPTH
Eeneath infilu'arive surface)
0 inches
2.1 Lnches
-18 Inches
TN (me^(eism drv soil)
@ackgror:nd zubtracted)
195
7
-3
Soil samples r;'ere ccileclei sex'eath 18 at-graie soii absor-orion rystems in Wisconsi:i'
.L\'erage s-vstem age 1.9 vears (.range 0'i -Z'-t years) measr:nni TT:f:."-
and cnionie'
-{.,,eraqe niUogen ccncenUadon 5le3-sureci at 18 sites are preSenreci below' lilS
inciicares a 37oh oirroe.o reciucrion after passing through '12 inches of soil'
nl (ms/Keigl drv soil)
(backgror:nd zubracted)
81
39
t1
51
DEPTI{
(B eneath i.nfiltrative surface)
0 - 6 lnches
12 - 18 Inches
24 - 30 lnches
36 - 12 inches
279
Alternativc SYstem Pedonunce
A range of alteraative Jeatment devices are avaiiabie for site conditions that are ,ns*itabie for
convendonal sy-srcnrs. Before . pro.L, *-d.rri.. is ailowed for r:sc in Washington' it is
evalrrated ior pedorrnznce, anci desigl guideiines m,sr be estabiished- Trearroent performanc:
mr:sr eqr:al or surPass expecurio* fI Iouventionai oq-site SyStelI,'' A-o uivantage of many
alternative s,v$e's or", .oor.ooori-ry".rt it 9. reiarive ease by wirich efflueut "etrd of
pipe,' qr.raliry cao be monitored. Hoo.rer, a disadvarrage for many altenative systems is
increased maintenance and operadon requireuents' Docunented ninogen rcmoval
performance is avaiiable for some aiternative s,v$e,s. .{dditionai evaiuauoo is necessarJ' to
conJirm performansg glaims, but the foilowing esrimares are a r:sefrri pianrung tooi'
Nitrogen Removal Performance Erpectations for
Alteruative On'site Sewage Systems
SYSTEM
Black Water llolding TaDk &
Gre;r Water Subsurface hfiitradon
Non-Wuer Carriage Toiies
Individual Extesded Aeration
ma*a*iExterdedAeration'*tthCyciedAeration
NimfrcarioryDenrrrfr cation Tickling Fiiter
Pear Fiiter
Ruck Sysrem
Iute:micent Sand Fiiter
Recirculating Sanci Fiiter
Recucuiarini S*A Filter with Aracrobic Filter
Recircuiarr-ua Sand Filter wirh Anacrobic Fiiter - Carircn
Recircuiatiai S-a Fiiter and Rock Storage Fiiter
Mound
Mor.rnd with Wetland
At-Grade EEiueut Distribution
Sources:
Ayres Associales (i991)
Degen M.B. (1991)
LaaK R (1981)
Loudorl T.L, (1985)
Pell, M. (i991)
Rorhberg. M. (1993)
REMOVAL
60 - 90 91o
50 - 90 0,/o
1< - :< c/^
50 - 800,6
J5 - 50 0,6
-:0 - 90 9/o
10 - i0 0,/o
40 - 60 9/o
70-80%
- 70 9/o
55 -i00 Yo
- i0 9/o
45 - 85 9/o
90 o/o
13 -i00 9/o
280
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Nitrogen Loading To On-Site Systems From Domestic Sources
I{vciraulic Loadine
The h1'&auiic ioading from a ciomesdc resid.ence is interminent and preciictable. The cyclic
ioaciing panern is d.irictly reiareci to the nr:mber and lifesqvle of the occuPants being served by
rhe s1,srem. The US Eulironmental Prorection Agency conducted ercensive surveys and
sruciies ro determine *'aslewarer srengrh and qurntiw. The averase ciaiiy flo'*'load from a
domesdc ciwelling reponeci b.'- rhe ensui-ng cioc::ment EPA-600/2 -2-78'173 is 170
iirervciavrcapita i;2.+ gallons/cia;-ucaoirat. The flow rate varies tbroughour a 24 hor:r peiod
from zero ro a maxinr:m quanury ciepencient upon the number of flxnrres capable of
simuitaleous use. Flo'*'reiuction cie',ices can reduce loading by approximateiy 10%-
Demo$aoir.ic data Washinmon Srate
The poouiation trends for Washingron Srare are suryeved and pubiished b;- the Washingron
State Offi.ce of Financial llanagernent 3.,'e.v- 10 years. The average nrrmber of resicients per
occupieci dweiiing in Washingron is f.-< persons per unit. The number of resicients per unit
compareci to the past re'rea1s a siigirt bur sready decline.
ii',,'drauiic loaciins Wasirinston State
Calcuiadons combimn-e rhise der:ograpiric satisrics. and nationai w'atelrse ciara indicate that
:he averase :otal ciaii.r- hycrauiic ioaci to an on-site wasrewater s-v$em is'll5 iitervday (94
gaiionsci..av). Since .Jre s,.,--sren is connec:ei iirec{y to '.he dweiliag by te buiiciing sewer. iI
i5o, ,..i.r"*' to adci any iafluence due lo inJlow or in-friuation for a prooe:iy ciesiened
instailadon.
Niaoeen loadine from a nnicai dweiline
Niuogen i:as been iciendfied as 'ire major gror.rndwatsl gsalaminant in teatei efrluent from
on-siie sv$ems. Therefore ir i.s aecessary io estimate the a-ount generarei by dwellings, and
derermine how much ma.v.' remain after on-site treatment.
A sun'ey by the U.S. Environmental Plotection Agency was conducted and reponed as
-
documenr EPA-600/2-2-78-17-". The ercensive sampiing population r:sed for this snrdy has
been rhe basis for waste trearrne[r engi-neering design for many years. Since dara was &awn
from a iarge population, the sratiscics are signi.ircant. This snrdy indicates that qpical septic-
tank inlluent ioncenration ratrges from 36 to 94 mg TNiI.. and after removing approximateiy
24 - 28%. the septic tank effluent requiring soil treatnent ranges from 26 to 76 mg TN/L-
Muhipiyi::g the average septic effluent concentration by average domestic consumption
provides an estimated mass loading to the soil treatment s,Ystem....
(170 L/day/capira) * (26 mgL efrluent TND = a.a gnldayicapita
(170 Lldaylcapita) i (76 mglL efrluent TIrI) = 12.9 gr.ldaylcapita-
Therefore, the average mass tesrling to the soil teatnent systen fttnges between 4.4 aad l2-9
gmldaylcapirz- Assuming that the national per capita loading rate is also indicative of
Washingron State residen-ts, this can be used to calculate loading from an average domestic
dweUing by applyrng census dara The average residential occupatrcy according to the Office
281
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of Financial Managelnent is 2-5 persons per dweliing'
(:-5 p"rrooi p.,-J*"ffi"gl ' ( 4'+ gmuday/capiP) = 11'0 gmidav
(3.5penonsperdweiling).(12.9--em,,day/capita)=31..3gmidav
In sr:rnmary, the total mass nitrogen load to treaEreil Processes downsreasr of the septic tank
for r.vpicai domestic dwellings in Wasfrington Sate is ixpected to range between 11 and 32'3
gw6y. Tbe mid point of tiis range is approximare1y 77gramsldav of total uitrogen'
EstimatingNitrogenLoadtoGroundwaterAfterTreatment
sepric iank efriuent niEogen loading :o ihe soil reatmeDt Process from a rypicai domesric
source is based upon an average a*.rGo..up*ty of l'5 people' anci nal3nal Y:],9*
for warer coosrmption- and ccoceoratioi. Mass aiaogen load reouiring soii ueament ls
er.pec:ei ro range i"ri*o i 1 and ,;.r;; .f ]?q-ar*ogto pti duy' The mrci poilt of 'lus
range is 2i grams of total nitrogeu e.i t, Th. brqT olo-og.o loading wouid normaily oe
associated with the rse of devices such as garbage grinders'
Biological denirif,cation ciurilg conveaional soii treatment is expected to remove 23o/o to
709/ooithenitrogenfromtheseptictankefrluent.Deairification."iitremovemoreniuogen
as efriuent passes tt'ough frner grain"a ,oii, rhan the **., grained soils as descibed beiow'
ffi erformanceisexpecredin.T+i,T:::t:-Y.:'"H::::f.""rJiTt'
These soiis promote rapid carbon -J oiiogen oxiclation in the upper soii region beneath rhe
bjiltrative surface leaving linle car[iGi-p"i*.a ae*rirrcation if anoxic conditions and a
sourcs of carbon establish below the disposat coB?oneil such as higb- or fluctuadng waler
tut.r. improved removal perforoance is expected'
11 grams/day with 23% removal = 8'5 gransi&y TN
32.3 grams/day with 23o'/o tesovai = 24'9 granslday TN
(Mid Poitrt is -i7 ganJdaY TNt
ffil restrict gas ransfer during bulk liquid lgy p"dods promoting
bioiogical a.-oin*,ion, improvin-g niuogen reduction to about 40%'
1I gramEday with 407o removal = 6'6 granslday TN
32 grams/day with 40% removal = l9'2 $afrslday TN
Mid Point is -13 gramVdaY of TN;
o
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O
i
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a
Fine Grained Sands
Gas ransfer is resricted longer after bul]i flow periods in fine grained soii improriag rhe
potential for bioiogical denirification.
11 gramVday with 60% removal = 1.4 grams/day T),i
32.3 gramvday with 600Z removal = 12.9 gams/day T){
(Mid point is - 8.5 grams/'day TI.i)
Silt or Clav Soils
Soils with very high r:niformiry coeficients or rhose that coutain silt or clay fi:rther res6ci
gas transfgr. and psrain nurienrs higher in the soii horizon. This is conciucive lo
denitrificadon and improved uprake b.".- pianrs.
1l gramvday ,;r;it}r 70% removal : 3.3 samVday TN
32.3 gramvday with 70% removal = 9.7 grams'day TN
@Iid point is - 6.5 gramVday INr)
Arid Regions
In an arid climadc regions where recharse is less rhan Eans-oirarion. a-uci arrificiai reclarse is
not pracdceC, evaporarion will keep uirogen iom being ransponei to rhe _grounciw'are:.
These regions are identifiable on soii maps as sair or alkaline-prone are3s. Thev can :.lso :e
idenrifieci b1' the presencs of naturai vegeadon ihat are adapteci io extemeif iow raiffail
condirions. Where evapo-transpirarion exceeds recharge, especiariy in deep soris. iirde if an;-
applied nirogen may leach to the gror:ndwater by becoming fixed geologicalll' as nirare sairs.
(The salt could take any of several forms such as caicium nirare. socijum nirare. potassium
niuate depending upon the source of positive ions.
lYitroeen Loss bv Vesetative Uotake
Woody vegeEtion with deep tap roots are not expected ro dramaticiy improve riuogea
removal performaace in coarse soiis unless they are pianted as a zupplemeil ro narive
vegetation and are within three feet of the disu'ibution tenches. However. uptake by rees in
fine grained soil or high water table regions can be significant. The nutrieut uorake rare is
also dependent upon type and age of Eees. Nurrient uptake by grass is aiso more significant
in fiae grained soil and high water table aree- To obtain a net loss of niuogen b:, piant
uptakehowever,vegetativegrourthshouldbeharvested. Araddirional 46Yoto 100%of the
applied nirogea could be lost by vegetative uptake. Significant vegetarive niuogen uprake is
most likely in areas with fine gained soii combined with shailow groundwaterq,,ithin reach of
grass roots. A shal'low flucnnting perched waler table is not only condusive to rapid
biological denitrificatiort but if within reach of roots wiil promote vegetativ. ,pt k.. Arter
the vegetation dies on the ground sr:rface, stored nitrogen experiencer nigl losses to the
aunosphere dr:ring decomposition.
283
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2U
o
a
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o
o
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e
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a
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285
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Hanley, KJ. (1985) Operatine the Activaled Sludee Prcc6s. Bnsbane' Australia-
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( I 976).
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ATTACHMENT D
MOUNTAIN RESIDENTIAL DEVELOPMENT
MINIMUM WELL PROTECTIVE DISTANCES
WELL WATER OUALITY
o
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I Mountqin Residentiol Development
Minimum Well Protective Distonces
Well Woter Quolity
Karl L. Ford, Julla H. Schott, and Thomas J. Keele, Ph.D-
Abstrrcl
The purpose of thls sludy wos to identify focbrs importanl to wellwoler
contaminition associoted with onsite wastewoler dbposal syslems. The study
sire is o mountainous porlion of Jelferson County, west of Denver, Colo.
Conlominolion of well waters was indicoted by concentration of nilrates ond
colilorm boclerio in excess oJ the Environmental Proteclion Agency's drinking
waier standords. Slalislical onalysb of lhe wellwater dala in this study indicate
that a well prolective distance oI INIt. has o probabilily of nitrale'nitrogen
conlaminaiion oJ 21.870; whereas, o 20O !t. dbtonce has a probability ol
nit ru t e-n it rog,en con I am ina I ion of 9.4 Vo.
Most local environmental hcalth
agencies regulate the siting and instal-
lation of onsite wastewater disposal
systems. Unless properly located and
installed, these sYstems maY be a
source of coliform or pathogenic
microorganisms and toxic products
such as nitrates. In order to prevent
contamination of water supplies and
the creation of health hazards, these
agencies may emPloY regulatorY
measures such as control of well con-
struction, subdivision lot size, well
depth, and horizontal well protective
distance requirements. These distance
rcquirements normally specify the
minimum distancc from the well to all
wastewaler disposal systems. A study
was made to evaluate the relative im-
portance of these faclors with respect
to well lvater contamination.
Journol oJ Environmentol Heslth, V. 13 (3)
t30- I 3t.
Karl L. Ford, Hcalth Scicnc.e Dcpartment,
California Stltc Univcrsity, Nonhridgc,
CA 9t330: Julia H. Schott. Jcfferson
County Health Dcpt., 26O S. Kipling. Lakc-
wood. CO 80226; end Thomas J. Xccfc,
Ph.D.. lnrtitutc of R.urel Environmcntal
Hcalth. Colorado Strtc Univcrsity. Sprucc
Hall, Ft. Collins, CO EOJ23.
r30
j
I
The Study Arer
The study arca, approximatelY 300
squarc miles in size, includes most of
the mountainous area of Jcfferson
County, Colorado. Much of the area,
which lies within commuting distance
of the Denver metropolitan area, has
experienced rapid growth; the popu-
lation of the area doubled from l96O
to 1970 and is increasing at approxi-
mately the same rate of growth. Of
the approximately 20,(n0 ycar-round
residents of the study area, nearlY
12,000 are using individual wells and
onsitc wastewater disposal systems
(6).
Metamorphic rocks and granite in-
trusions comprise most of thc bcd-
rock, and the rock contains numerous
faults and fractures. Fractured bcd-
rock constitulcs the principle aquifcr
in the mountains. The porosity of thc
aquifer is low and water availability is
correspondingly low with yields of I
gpm common Cr). Sand snd gravel
deposits occur in the valleys and form
the second most important source of
groundwater in the arca. The dluvial
wells are characterized by highcr
storage capacity and more stable
water levels than wetls drilled in bcd-
rock.
Journal of Environmental Health
[tE*rvED
tlAR 2 0 rssu
RESOI.reEl,El}CEmrel $€.
Soils throughout the study area are
quite thin (superficial), normally re-
flecting an averag,e topsoil depth of
12 lo 24 inches, and are underlain
with decomposcd bedrock of varying
density and thickness; this interme-
diate zone from soil to bcdrock
ranges from 0 to over 20 feet. Most
soils in the study area are not suitable
for convcntional soil absorption
waslewaler disposal systems. Not
only are the soils too thin, but thc
fracture zones allow rapid movement
of the wastewater effluenl. Under
continuing pressure for development,
Jefferson County has allowed subsur-
face sand filters and ripped base
disposal fields that have been in-
stalled in accordance with the design
of a profcssional engineer.
Methodology
Wellwater samples were collected
as an indicator of thc quality of the
groundwater bcing used for human
consumption. Thc 164 wells utilizcd
in the study werc nol selected at ran-
dom. The wcllwater samples were
taken by the staff of the Jefferson
County Health Department from
wells subjected to a sanitary survey
during the years 1975-1977. On thc
basis of sanitary surveys, prcvious
Vol.43, No. 3
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o
samplcs, or omer complaints, some
of thc wclls wcrc known or suspected
to be contaminatcd. Despite this,
only 20.7olc of thc wclls sclcctcd for
the study actually cxcccdcd the
Environmental Protcction Agency's
(EPA) standards of l0 mgll for
NOrN (3).
The wclls werc samplcd and ana-
lyzcd for coliform bactcria and
NOI-N in accordancc with the APHA
Standard Methods for the Examina-
tion of Water and Wastewater (2). A
sanitary survcy was conducted for
cach well in order to identify possible
sourccs of contamination. Since wcll
construction was thought to be an im-
portant factor influencing coliform
contamination, the survey included a
well inspection. The following criteria
wcrc utilized to classify wells of un-
approved construction (5, 9):
l. lack of a watertight sanitary
seal;
2. pit installation;
3. dug well or spring; and
4. inadequate formation seal.
Also investigated were site factors
thought to be related to contamina-
tion:
l. well dcpth;
2. wcll protective distance;
3. geology (some data collected);
and
4. lot size.
Domestic livestock was initially con-
sidered a factor contributing to the
(rccurrence of contamination but, on
the basis of the sanitary suryeys, wns
eliminated as a source of contamina-
tion in most instances.
Well Construction ond Deprh
Based on the abovc crileria, wells
wcre classified as eithcr approved or
unapprovcd construction. Coliforms
wcre found in unapproved wclls more
frcquently than approved wclls, but
nitrates wcre found cqually in ap-
proved and unapproved wells Cfablel). Wcll construction was not found
to bc statistically related in nirrate
contamination. Coliform contamina-
tion was found equally in shallow,
unapproved wells as in deepdrillcd,
unapproved wells. Coliform contami-
nation was not found to be rclated to
lot size or distancc.
Novembcr./Decembcr. I 980
Teblo i
Comprrlron ol colllorm rnd nllrrio (NOri{ conl.mln.tlon
lound ln rpprorod end unepprorad con.ltuclad r.l!a.
Well
Conat uctlon
tT WellsWith
Colilorms
t6 Wells
NO|-N>lorng/1
Xlto..N
Concenkation
Approvecl
Unapproved
17.6
23.7
r0.8
20.3
4.00
1.70
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Trblo 2
Ptrcrnl of remplcd rollr orcoedlnC th. nllrrtlnltrog.n rlrndrrd
tor rlx rolldl.trnca eroupa.
Distance
Group
(Feot)
Number
Sampled Wells
Mean
CXstanco
(Feet)
Number of
Contaminaled Wells(el Plb)
sEo
61-SO
91-120
121-150
151-210
< 210
11.2
77.7
r03.3
r 35.4
195.5
430.8
40.0 - .40625.9 - 1 .O5120.9 - 1.331r4.3 -1.79110.7 -2.1227.7 -2.369
1 37.1 20.7 - 1.343
l') Fo'r these purposes, a woll was considered contaminated it lho nitro9en-nit.ale lsvel (NOI-N)
Gxceeded the standard ol 1O mg/lit6r.
lbl P denotes ttte percentage ol wolls oxceeding the siandard o, I O mg/liler.
lclLP denoles tre looit tsanslorm ol P. LP-log. (P/(lOO-P)).
25
27
43
2A
2A
t3
to
7I
4
3
t
164
Prolective Distance
Whereas coliforms werc not cx-
pressly associated with the well pro-
tective distance, the nitrate concen-
trations were. In order to examine the
relationship betwecn welldistance
and nitrate-nitrogen concentration,
the wells were categorized both by
well distance (six groups as shown in
Table 2) and by contamination or
noncontamination. A well was coded
as contaminated if the nitrate-nitro-
gen level exceeded the health standard
of lO mgll. As seen in Table 2, the
pcrcentage of wclls exceeding the
nitrate-nitrogen standard decrcases
sharply with increasing wcll distance.A wcighted rcgression analysis
showcd a highly significant quadratic
relationship between the logit trans-
formation of thc pcrcentage of con-
taminated wells and the distance of
thc well from the nearcst wastewater
disposal system. The percentage vari-
ation explained by this regression
analysis 6.e., R') was 98.590. A plot
of the predictive equation for the per-
centsge of contaminated wclls, along
with an approximatcgl9o confidencc
band and the observed pcrcentage of
contaminated wells, is givcn in Figure
l. C-alculated values of the cstimated
pcrccntage of wells exceeding the
nitratc-nitrogen standard are given in
Journal of Environmental Hcalth
Table 3 for selected well distances.
For example, lhe estimated percent-
age of contaminated wells with a well
distance of 200 feet is 9.490 with an
approximate 9590 confidence interval
of 8.2 to l0.E9o.
Whereas the correlation betwecn
nitrate-nitrogen and well distance was
statistically significant, the consider-
able variation of nitrate-nitrogen
levels within the well distance cate-
gories indicated the potential for
other explanatory sources of varia-
tion. The effects of other variables,
such as well depth and lot size, on
nitrate-nitrogen levels were statistical-
ly investigated via multiple regression
analysis. However, the addition of
these other variables did not con-
tributc significantly to explaining the
variation in the nitrate-nitrogen
levels.
Geologlr
The subsurface geology of a given
site was a factor that was bcyond the
scope of the study to properly evalu-
ate. Some secondary data werc com-
piled from USGS geological maps
and other sources. Well logs wcrc
considered a potentially valuable
source of geological data for furtherinvestigation. -lo
t3l
Overall
o
(Feetl
frbb !
Fogronlon ..llm.l.3 ol lh. p.rc.nl (P) ol rollr orcrcdlng'10 mglt XOrll ol rrlor.
rlong wllh C5% conrldonco lnlrrulr, tor roloclod r.lldl.hnc. (O).
Approximale 95%
Conlidence lntorval lor P
56.1
35.8
21.8
13.1
9.1
7.2
6.3
6.2
6.9
4.7
12.3
reason that coliform contamination
was found cqually in shallow, unap-
provcd wclls as in dccpdrilled, unap-
provcd wclls is that surface contami-
nation-bearing coliforms may still
cnter the wcll head of a poorly pro-
tccted well and flow down thc casing
into the wcll. For these rcasons, the
oocurrence of coliforms in wellwaters
may bc considercd I bctter indicator
of impropcr well construction than of
groundwater contamination.
Since the nitratc-nitrogen may be
8n indicator of wastewater ccrn-
tamination, it is important to con-
sider how it is formed. Nitrate-nitro-
gen is formed from the nitrogenous
waslcs in percolating efflucnt undcr
aerobic conditions, but unlike other
effluent products, nitrates are water
soluble and are not effectively re-
moved by soil filtration. Consequent-
ly, nitrates tend to accumulate in the
aquifer. Since the presence of nitrates
was found to bc statistically unrelated
to wcll construction, nitrates may be
a better indicator of well water con-
tamination from wastewaicr disposal
systems than arc coliforms.
Lot size, as relatcd to well water
contamination, is an important con-
sideration for land use planning. In
fact, since the relative spacing of wcll
o
50
100
150
200
250
300
350
aoo
450
500
62.1
32.4
19.3
12.O
8.2
8^3
5.4
5.3
6.O
7.6
to.8
69.8
39.3
24.1
15.6
10.8
8.3
7.2
7.O
7.5
to.o
't4.o
It
IIi
t
t,
I:
t
It
Discusslon
The well protective distance (and
indirectty lot size) does not entirely
explain or predict contamination,
probably due to the geologic variable.
Hofstra and Hall (4) emphasized not
only the importance of wcll construc-
tion but also stressed the significance
of geologic factors in explaining the
occurrence of contamination in well
watcrs. Geologic factors arc difficult
to deal with in mountainous cnviron-
menls due to the variation in the
depth to bedrock, fracture direction,
speciFrc yield of the aquifer, Btrd
other factors thal defy easy generali-
zation. Geological considerations
may also explain coliform contamina-
tion when well construction is ade-
quate. Waltz (8) and Allcn (l) have
shown that the fractures in crystalline
bcdrock are not effective in filtering
the bacteria associated with waste-
waler effluent. They have also shown
that the orientation of thc rock frac-
tures does influence thc dircction and
travel path of the contaminants.
These studies confirm that simply
locating the wcll ropographically
abovc the wastewater does not pro-
vide any assurances that leachficld
effluent will not flow into the wcll.
ln regard to well construction, onet
Flguro I
Pbl ol atllm.lcd P.rc.ntago P ol rcllr arcocdlng lO mg llOr-l{ por lltrr relcr er r luncllon
ol dl.trnc. D lrom lho n.rrott r.3lcwrlor otllutnt, rlong wlth rpprorlmrtr e 516 conlldoncobrnd rnd.call.rptol ol obroryod p.rccnt g.t.
P
t0
65
t0
a5
a0
t5
t0
25
20
t6
t0
6
oo TtRERIFEFtRSPtsEPE?GtGaGaNc1cratlttrr!?ta6
t32 Journal of Environmenral Health Vol. 43, No. 3
o
o
o
o
o
o
o
+.
Ot
Or
O-.
tt
and disposal syslems largely dctcr-
mincs thc lot sizc requircments, lot
sizc is closcly rclated to the minimum
protcctive distance rcguircments.
When nitratc conccntrations for thc
study arca werc spotflapped, the
localitics of extensive nitrate contami-
nation were seen to be associated with
incrcased housing density. In particu-
lar, zones of nitrate contamination
greater than l0 mgll were found lo
be associated with housing densities
grcater than one dwclling unit per
acre and with well protectivc dis-
tances of 100 feet or less.
Statistical analysis of the study
data indicates that, for similar moun-
tainous terrain, residential develop-
ments which provide for a well pro-
tective distance ofonly l0O fcet facc a
21.89o probability of exceeding the
NOr-N health standard; whereas, the
probability with a well prolective dis-
tance of 200 feet is 9.490. Thus, a
minimum protective distance of 200
feet is more reasonable than 100 fcet
in preventing nitrate health hazards in
well water supplies. A 200-foot mini-
mum protective distance requircs
two-acre minimum lot sizes and with
adverse lopography and full subdivi-
sion development, cvcn two acrcs
may be inadequate to maintain 200-
foot minimum protective distances.
Evidence of contamination suggests
that water quality and health hazards
may prove to be more significant
limitations on mountain residential
development than merely water
quantity.
Rclcrcnccri
l. Allen, J., end S. M, Morrison (t9?3)
Bacterial movcmcnl through fractured
bcdrock. Ground l*'oter ll:6-10.
2. Amcrican Public Hcalth Association,
Amcrican Watcr Works Association end
The Watcr Pollution Control Fcdcration.
eds. (1976). Srondord Methods tor the
Exominolion o/ l,l'oter and Wostewoter,
Washington, D.C.
3. Environmental Protection Agcncy (t975).
Notionol lnterim Primory Drinking Woter
Regulotions, EPA publication l5'10/9-7G
003, 5-?.
4. Hostre, T. rnd D. A. Hall ll975l, Gcologi-
col Control oJ Supply and Quolity ot
Water ln the Mountainous Port ol Jdler-
son Counly, Denver, Colorodo, Colorado
Gcological Survcy. Bullctin 36:43:14.
5. Jones. E. (1974), Eveluating wcll con-
riruction. J. Envircn. Hcalth 36:556-5&.
6. Jctfenon Counry Plonning hpnmcm
(1976), Mountoin Arto fupulation Eli-
moles.
7. Snow, T. (1972), Mounloin groundwatcr
supplies, Thc Mountoin Gaologisl, l0:19-u.
November/Dccembcr, I 980
t. Wrttz, ,. P. (t972), Mcthods of Seologic
cvaluation of pollution potential !t moun'
rain homoitcs, Ground Wotcr 10:1247.
9. Whitscll, W. t. ud G. D. Hutchison
(19?3), Scvcn dangcr signals for individual
urtcr rupply. Tronsoclions ol ,hc ASAE
t6.
Stored Petroleum
Vapors Regulated
EPA rcgulations io Prevent vapors
from petroleum storage tanks went
into effcct with publication in the
April 4, 1980 Federal Register. They
affect tanks on which construction
was begun after May 18, 1978, that
have storage capacity Srcaler than
40,000 Sallons and that contain
petroleum liquids with a vapor pres-
sure grealcr than 1.5 Pounds Per
squarc inch. Exempted are those used
at drilling sites to store crude oil or
natural gas, but only if theY have a
storage capacity less than 420,000
Ballons.
The regulations arc issued under
authority of Scction I I I of the Clean
Air Act protecting the public hcalth
or welfare. They require the use of
improved emission control technolo-
gy for storag,e tanks cquiPPed wilh
external floating roofs. They rcquirc
two scals and minimizing thc gaps be'
tween seals and tank walls. As an
alternative to floating roofs, tank
owners may install a vapor rocover)
process or any othcr system thal
reduces VOC emissions to the samt
degree as the roofs.
Radiation Book Out
Effluent and Environmenta
Rodiation Surteillonce is a new pub
lication of the American Society fo-
Testing and Materids, the outcomr
of the July .1978 Johnson Confcrcnce
It includes 30 papers that reviev
methodologies, data and interpreta
tions obtained from the monitorin6
of cffluents from thc environmentl
surrounding nuclear facilities. Thr
text specifically addresses the tech
niques used in measuring the radio
active effluent from facilities usint
nuclear materials and monitoring tht
environment in order to delermin(
the impact of these materials or
people and the environment. For in-
formation, contact ASTM Sale:
Service Dept., 1916 Race St., Phila-
delphia, PA 19103.
o
.iiJ
.! -i
Journd of Environmentd Health
MINIMUM HORIZONTAL
OF A SEWAGE DISPOSAL
APPENDIX B
DTSTANCES IN FEET BETWEEN COMPONENT
SYSTEM AND PERTINENT GROUND FEATURES -
L-ia
lil tL,tzFJ{p-ul ?
IE=tuAYdaDltLoEu'zo9oE=
=o_<Itri(n/)o-
F,-)l
(ro
FJl
r>icEi(L
I
I
I
I
!
(f
,J =z^Yfi EE!trJ ; !l ---t 1go>(L(oF-
3E?tt
ErEBS-FrcaccO
EEf;=ilH
Er,gF;;(,oJ.tr<<(otuZ>O-<col(/)tLF
(ro
z.OoFz<o(fL
d-z9o
da-rs
OJo.@
>Fu)aoouJ ul
==
2*- gskfi
E:E
trH2-."6
u-r(,F
?EE>aao>rD<(r)<
aL(!
ul(,
(L
ulula
WELLS, SPRINGS,
SUCTION LINES
50 50 200 (A) (B)60 1oo (B)(A)(B)200
POTABLE WATER
SUPPLY LINES
10 10 25 10 25 50
CISTERNS 25 10 25 25 25 25
DWELLING OR
OCCUPIED BUILDING
5 15 20 15 20 20
PROPERTY LINES 10 10 10 10 10 25
SUBSOIL DRAINS 10 (c)10 25 10 25 25
LAKE, WATER
COURSE, STREAM
50 (c)25 50 25 50 50
DRY GULCH 10 (c)10 25 10 25 25
Note:
A.
When a geological or other conditions warrant, greater dislance may be required.
Distance separalions belween 100 and 200 feel may be permitted if adequate geologic data,
meeting the Boards' guidelines is submitled and approved. When geologically appropriate distance
reductions shall affect components on lhe proposed building sile ralher lhan components on
adiacent developed sites.
Add I f eet additional r.listance for each '100 gallons per day design f low over 1000 gallons per day.
Crossings may be permitterl wlrere pipelines are conslrucled of sufficienl strenglh to contain flows
under presstlre.
73
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O
ATTACHMENT E
COLORADO DEPARTMENT OF PUBLIC HEALTH AND ENVIRONMENT
o
o
Report Date: 10/23/97
Contact: KirSerting, Chuck
Contact Phone: (970)915'7481
Operator: CoreY, Chuck
of,6rator Phone: (970)945-7481
Resident Poputation: 220
Xon-Transient PoPutation: 0
Transient PoPutation: 400
service Connections: 133
r***i******* souRcE INFORI,IATION
se_id srcnm src
OOl tl01 ret t #1
002 tl02 ret t #2
county: Garfiel'd
Active Status: Active
Activation Date: 0/
Systern Begin Date: Ol
System TYPe: Cotm"nitY
. Systern Source fype: Ground l'later
OPen Year Around
***t***********i*t**lt****
Disinfection Haiver ? No
Bacts Required: 1
Bact Cycte: llonthtY
Nitrate Schedute: 2rd Quarter
Chemicat Schedute Group: 1
Inorganic Schedute: Znd Quarter
Radiotogicat Schedute: 2nd Quarter
organic Schedute: chaffee/Lautenberg
na
scDIUH SE-ID-'| sE-lD-z sE-lD-3 sE-lD-4 SE-ID-5
17 001
1tt 001
15.4 002
COLORADO DEPARII,IENT OF PUBLIC HEALTH AND ENVIRONI{ENT
Corpliance llonitoring and Data t{anagefilent Unit - t''ocD
Note: cofiputer data is atrays sr.rbject to error. lf data appears unusual or questionabte,
ptease confirm the vatidity xith the Drinking tJater Section at (305) 692-3500-
UATER OUALITY DATA FOR ID 123170 Cotorado,4ountain Cot Iege
3000 C R 114 - SPring vattey
Gtenlood Springs, CO 81601o
o
a
o
o
o
a
o
o
se-rec-type se-code avait sanpoint selter-id totatdepth aquifer
s G P .F. 320
SGP.T.260
0'l/02/97 r m
01/?1/97 r m
0?/18/97 r m
03/04/97 r m
03/17197 r m
OLIO||97 r m
04/22/97 r m
05/06/97 r m
05127197 s m
06/02197 r m
06/24/97 S m
07/01197 r m
07/15/97 r m
08105197 r m
08119/97 r m
09/08/97 r m
09/?2197 r m
10106/97 r m
**t****************** RECEIIT BACTER I OLOG I CAL **********tt*t*****i*****
***s=safe ***** u=Unsafe ***** N=lnvalid**t*
sadp-date type testmeth quantity tcjres fepres invatid
2s
1s
1s
1s
1s
1s
'l s
lX T
1s
1]l s C
1s
1s
1s
1s
1s
1s
1s
1s
***tt*t**t*** ORIGINAL INORGANICS ******t***t*****t*tltttli*t
t***** att resutts and l{CLs expressed in mg/t or pFn r*t*tt*
tr l,lcLs are 0.05 2 0.005 0.1 4.0 na 0.002
SA}IPLEDATE ARSEilIC BARIUH CADI4II'I{ CHRCI{IUI{ FLUORIDE LEAD I{ERCURY
o7/2gt870.0000.0000.000000.00000.1600.00000.00000
ogtlTtso o.o0o 0.100 o.ooo00 o.oooo o-300 0.0000 0'00000
o8to7tg5 o.ooo o.o2 o.oooo 0.ooo 0-26 0.000 0'0000
0.05 na
SELE}IIUI.I SI LVER
0.000 0.0000
0.000 0.0000
0.000 NT
a
**********itii )lEu lxoRGANIC PARAI,IETERS r*****t*t******t***
*ttt** atl resutts expressed in ,g/t or pgn *i'ttt*tt*t***
*t*t******tt** TESTtIIG BEGAII JAll l, 1993 ***it**t*ti*******
** HCLs are 0.005 0-OO4 0.2 0.1 na 0'002
O SAHPLEDAIE ANIII,IO}IY BERYLLIUI't CYANIDE }IICKEL SULFATE IHALLIUI'I CO}IPOStTED SE-ID-1 SE-ID-2 SE-ID-3 SE-ID-4 SE-ID-5
08/07/95 0.000 0.000 0-000 0.002 75 o.ooo . F. 002
****!t****t*t***t** ll I TRATE/ll I TR I TE t**t*****t****t**t***
**t*t* atl resutts expressed in,ng/|, or pFn t*t******tt*
** llcLs are 10.0 1.0 10-0
sanptedate nitrate-n nitrite-n no3-no2-n se-id-l se-id-2 se-id-3 se-id-4 se-id-5
o7t2gt87 0.96 llT 001
og/17 tgl o.7o llr 001
o6to8tg4 1.17 BDL 1 -17 oo2
o8to7tg5 0.65 0.00 0-65 002
o6t26tg6 0.18 0.00 0.18 002
o6/04t97 0.56 O.O0 0.56 002
*****************tr LEAD/COPPER TAP IIONITORING DATA ****t***t**
*r*i* levets are 90th percentile tevels expressed in m971 *****
beg-corpt i erd-corpt i pb-g0th cu-90th
07tol/93 12t31/93 0.006 0.57
01/01/94 05t30t94 0.007 1.16
01t01/95 1?/31195
01/01t96 12t31196 0.006 0.64
01to1t97 12131197
****it**l********* RAD I OLOG I CAL **t****t*'**iit*i**t*it**
**** a[[ results expressed in pCi/t, except Ts in rng/[ **r*
PLANTNUTIBR SAI,IPLEDATE SAI'ITYPE ALPHA ADJ-ALPHA BETA RA226
o
o
O
o
o
o
a
1 01 /14/tt6 G
rJ02 06108194
rJ02 06/04/97
ptantnunbr Ptantname
1 Coto l'lnt. Cot tege
8.0 6.0
3.9 uT 4.1
4NT4
0.0 0.00
llT
)lT
RA228 RA226-228 URANIUI,I IS RADON-222
0.00 0.00 0.0 610
}IT ilT }IT 592 NT
NT NT NT 380 NT
**********t****t** coRRosIvlIY ****t**t*****tl*t*****t**l
***** atl units are rg/t except Langtier, Pfl, ald tenp *t**
sanptedate tangtier tot-al,k ca-hard ph tds r'ater-terp chtoride sutfate
ogt'.|/go Is ?76 &-1 8-14 Is 20c
*** There ras no trihatomethane data found, Required for com.rnity systefirs serving 10,000 or npre only' ***
Phase Mcrs *t*****t****t**t*Note: tnctuded as part of Phase IIlV organics as of'l/1193'
Refer to fite for information on detects'
sanpl,edate detected
12/13/90 [o voc's detected.
O ******!r***r**fi REGULATED PHASE I/lllv oRGAlllcs **tr**rtt****'r
Sources: 002 Og/O7tg3 Carposited: I Hith: 123670 *r* There Here no regul'ated detects in this salmte' tt*
Sources:002 06t17t97 CorPosited: F *** There rere no regutated detects in this sarpte' ***
o
a
*.*t******t**r* UIIREGULATED PHASE I,/l I/V ORGA)'Itcs *************t*i,lote: Detections of Trihatornethanes are not printed'
Sources:002 O9/O7tg3 CorPosited: T rith: 123670
lilonitoring is required. No stardards have been set'
** There r.ere no unregutated detects in this sanpte' ***
o Sources:002
Naphthalene = 0.6
06/17/97 conPosited: F
o
********i*** CHECK SAI4PLE TRACKING IIIFO !r*******tt****
Parameter: NaPhthatene 91-20-3 2218
Source:002 U02 tlett
check sanpte letter date: 07108197
Originat sanpte date; 06t17t97 Resutt: 0.5 uglt
ltCL Viotation Estabtished ? ll
uas presence of contaminant confirnred ? ll
Check 1 resutt: <0.5
Check 2 resutt: <0.5
us/ t
ugl t
07/24/97
09/02/97
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*il************i*** VIOLATIONS - ( Bact and Tur.bidity ) ***************
BEG-coi{PLIEND-col.lPLIvIoL-TYPECoNTAI,IINATREQSAI{PLESvALID-SAI
02/01/94 02t28/94 23 3100 1
************* cHEl,tIcAL VIOLAIIOIIS *********rtt******
beg-conpt i end-corpt i viot-type contaminat reqsanptes vaI id-sam
01/01/93 12/31193 03 1040 1
i*************t** ENFORCET{ENT ACTIO}lS for cHEitS t*tt***t**i
**** SFJ = viotation letter - SoX = noH in corptiance ****
enf_date epa-code tyP€-tetr corrnents
06/08/94 sox
*** There Here no state monitoring viotations found' ***
*r* There are no outstanding enforcemnt orders. *r*
Ptease Note:NT = Not Tested
ND = None Detected
BDL = Betor Detection Limit
< synsol for tess than
na = Hot Appticabte
I,ICL-VIOLAT ENF-DATE TYPE-LETR EPA-COE
04/?1/94 1 sFJ
mt-viotat enf-date type-tetr epa-code detete
0.oo0ooooo 03/06/95 1 so6
RESULT
resu I t
0.00000000
GU = ground Hater
Sl, = surface rater
cHrIStJ = ground xaten under the inftuence of surface rater
l4CL = rnxirn"m contaminant levet
VOC = votatile organic chemicaI
STJTR = surface Hater treatfi€nt rute
o
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Report Date: 10/23197
contact: Lestie, Scott u274
Contact Phone: (970)945-91?1
operator: Lestie, Scott u274
clperator Phone: (970)945-6059
Resident PoPutation: 88
Non-Transient PoPutation: 0
'l'ransient PoPutation: 0
Service Connections: 48
county: Garfietd
Active Status: Active
Activation Date: Ol
System Begin Date: 0l
System Type: Cotm.mitY
System Source TYPe: Ground Llater
open Year Arourd
Disinfection Uaiver ? Io
Bacts Required: 1
Bact Cycte: l,lonthtY
Nitrate Schedute: 1st Quarter
Chemicat Schedule GrouP: 3
Inorganic Schedute: 1st Quarter
Radiotogicat Schedute: 1st Quarter
Organic Schedul'e: Routine - 4 Quarters
coLoRADoDEPARTI.IE}IToFPUBLtcHEALTHANDENVIRoN].|ENT
Conptiance llonitoring arrd Data l{anagernent Unit - UOCD
Note: Cofip{.tter data is atrays subject to error. If data aPP€ars unusual or questionabte,
please confirm the vatidity r.ith the Drinking trater section at (305) 692-3500.
IJAIER OUALITY DATA FOR ID 123485 Red Canyon llC
ATTH: EPC - Scott Lestie
PO Box 493
SnorilBss, C0 81654
****r******* souRcE INFORITATION *******t**********t******t
se_id srcntm src se_rec_type se_code avait sanpoint setl,er-id totatdePth aquifer
OO1 !,01 tJel'l,#l s G P 'F' 150
002 l,O2 rett #2 (fire erprgency onty) S G E 'F' 300
003 GtlTPOl Red canyon LITP P T P 'T'
ii*r******t*t*i***** REcEllT BAcTER I OLOG I CAL *l**tti*****t**t***tt****
*** S = Safe t**** U = UnSafe ***rt* N = InVa[id *t**
sanp-date type testmeth quantity tcJcres fe3res invalid
01/27197 r m
0?/25/97 r m
03/27/97 r m
01/29/97 r m
05/?8/97 r m
06/26/97 r m
07/23197 r m
08/26197 r m
09/30/97 r m
1s
1s
1s
1s
1s
1s
1s
1s
1s
**r***i****t* ORTGINAL INORGANICS *t****i**r****i*ttt********
t****t att resutts and l{CLs expressed in mg/l' or ppn *******
a ** }lCLs are 0.05 2 0.005 0 - 1 4.0 na 0.002
SAHPLEDATE ARSE}IIC BARIUI{ CADilIUil CHRO'IIUI'I FLUORIDE LEAD }IERCURY
07/22t85 O.OOO O.OOO O.O0OO0 O.oooo 0-200 0-0000 0.00000
og/15t8g o.0oo 0.020 o.ooo0o o.oooo 0.180 0.0050 0'00000
03T24/94 BDL BDL BDL BDL 0 .3? 0.007 BDL
o3t31tg7 o.oo0 o.oo o.oooo o.0oo o-22 0.000 0.0000
o
*****t***t**** llEll INoRGAillc PARATIETERS tt*ttt***t*******tt
t***** alt resutts expressed in mg./t or Ppn trtt***t*****trt
i*tt********** TESTIIIG BEGAII JAI 1, 1993 !t*tttt**t*t!t**tt**
** l{CLs are 0.006 0-004 0.2 0.1 na 0'002
O sAxpLEDATE AllTtltolly BERvLLIIIt cyAlttDE lllcKEL SULFATE IHALLI$I c$lPoslTED sE-lD-1 sE-lD-z SE-ID-3 sE-ID-/r sE-lD-s
0.05 na
SELE}IIUI4 SILVER
0.000 0.0000
0.000 0.0000
0.003 NT
0.000 uT
na
soolull sE_lD_1 SE_
11 001
11 001
15.3 001
12.9 003
ID 2 SE-ID-3 SE-ID-4 SE-ID-:
o
01/24194 BDL BDL
03t31/97 0.000 0.000
o?/?2t85 0.00 llr
o9/15t89 0.26 llT
03/18/93 0.026 0.00 NT
03t21t91 0.02 BDL 0-02
o3/09t95 0.06 0.00 0.06
o:3/?7t96 O.Tt 0.02 0.79
03t31t97 0.08 0.00 0.08
BDL BDL 23
0.000 0.000 ?1
BDL
0 .000
001
001
001
001
003
003
003
o.o 0.0 9.0 0-00
3.5 1.7 4.1 0.10
6 Nr <8 tlT
.F.
.F.
001
003
o ::::::..:ii-:"":i:" ":il::i-l:-il;, ":'*"
*::::::::::::
** l{CLs are '10.0 1.0 10.0
sanptedate nitrate-n nitrite-n no3-noZ-n se-id-1 se-id-2 se-id-5 se-id-4 se-id-5
o
*r*****r*********** LEAD/COPPER IAP I'loltIToRlllc DATA *tt*tt*i***
*!r*** tevets are 90th Percentite tevets expressed in lg71 ****t
beg-coopl, i end-conpt i Pb-9Oth cu-9Oth
a7tO1t93 12t31/93 0.007 0.16
g1/o1/94 06t30/94 0.008 0.08
01/o't/95 12t31195 o.oo5 0-35
01t01t97 1?13',v97
*i***t****t****t*t RAD I OLOG I CAL t**trttlt*tt****t**tt***it*
**** a[[ resutts expressed in PCi/t, excePt Ts in mg/[ *r**
PLA}ITNUI{BR SAI,IPLEDAIE SAI{TYPE ALPHA ADJ-ALPHA BETA P'A226 RA228 RA226-228 URAXIUI'I rS RAD0I-222
o.o0 0.00 0.0 550
0.oo 0.00 1.7 0
NT }IT NT 450 NT
1 03/?7/87 c
1 03127/91 tl
GHTPo1 03/27/96
rr*t****t***at**** coRRoslvlTY tt***t****tr****tttt**t*tt
$ii* atl units are nr9/t except Langtier, pH, and tenp **r*
sanptedate tangtier tot-atk ca-hard ph tds Hater-teilP chtoride sutfate
ogtls/8s -.107 257 50.5 7-6 559 49 t
** There Has no trihatornethane data found. Required for comrunity systems serving 10,000 or more onty' *r*
*****************t Phase t VOCrS **t****t******it*llote: tnctuded as part of Phase Illv organics as of 111193'
Refer to fi l,e for infornntion on detects'
ptantntnbr Ptantname
1 Auburn Ridge-Los Amigos
sarptedate detected
O3tO6l91 llo voc's detected.
Sources: 005 003 O6l26tg5 Conposited: T rith: 123155
2,4,-D = 0.8
****rr*r**rt*.* UNREGULATED PHASE I/lllv oRGAIIICS *t**trtiitt**i*Note: Detections of Irihatomethanes are not printed'
l,lonitoring is required. llo standards have been set'
*** There rere no unregutated detects in this sanpte' ***
Sources:003 O3lZTt95 CorPosited: F
o
Sources: 003 003 Corposi ted: T rith: 123155 *** There rere no unregutated detects in this sanpte- ***
o
o
l.
*t*t***rt*fi cHEcK sAl{PLE IRACKTNG IIFO *****tr****tt**
Pararneter: 2,4,0 94'75-7 2105
O Source: 003 GttTOl llater Ptant (retts #1 ard #2)
Check sarpte letter date: 09111/95
originat sanpte date. 06126t95 Resutt: 0'8 uglt
l,lCL Violation Establ ished ? il
llas presence of contaminant confirmed ? !l
Check 1 resutt: BDL
Check 2 resutt: BDL
us/ I'
us/ t
03t28/97
06/27 /97
******************* vloLATIoNs - ( Bact ard Turbidity ) !r***t*****t*i**
BEG-CO,IPLIEND-COIPLTVIOL-TYPECONTAI'IIXATREOSAI{PLESVALID-SAH
1o/o1t8s 1ol31l8g 02 3o0o 0 0
*** There Here no chemicat viotations found' r**
*** There Here no additionat chemical enforcement actions found' ***
*** There raere no state monitoring viotations found' ***
*** There are no outstarding enforcement orders' ti*
Ptease Note:NT = Not Tested
ND = Xone Detected
BDL = Betox Detection Limit
< synbot for less than
na = llot Appticabte
GL, = grouM xater
sll = surface rater
GtJulstl = ground rater under the inftuence of surface xater
HCL = maxim'rn contaminant [eve[
VoC = votatite organic chemical
St,lIR = surface Hater treatment rute
RESULT
4.00000000
I.ICL-VtOLAT ENF-DATE
1.00000000 0?/05/90
TYPE-LETR EPA-COE
1AE
o
o
RePort Date: 03/'19/98
contact: Livingston, LYnn
Contact Phone: (970)915-9393
Operator: Livingston, LYnn
Operator P6s6g; (970)945-7337
Resident PoPutation:0
Non-Transient PoPutation: 10
Transient PoP.rtation: 60
Service Connections: 5
***r*t****** souRcE INFoRI.|ATION
se_id srcnun src
OOl tl01 xet t #1
evE$
o
coLoRADoDEPARTI.{ENToFPUBLIcHEALTHANDE}lvlRoNi,|ENT
Conptiance l.onitoring ard Oata l4anagerEnt Unit - lJocD
Note: Corqruter data is atrays subject to error. If data aPpears unusuat or
ptease confirm the vatidity rith the Drinking l,later Program at (303)
I,'ATER AUALITY DATA FOR ID 223359 llid Vat Iey l{art, Inc.
6818 Hxy 82
GIenwood Springs, C0 81601
county: Garfietd
Activestatus: tnactive
Activation Date: 07/96
System Begin Date: 0/
System Type: Transient Non-Cofirrunity
System Source TYPe: Ground ['Jater
Open Date: 01/01
cl.ose Date: 12l31
* * ***** ** * *t **1 I tt*** *****
Disinfection tJaiver ? No
Bacts Required: 1
Bact Cycte: l'lonthtY
Nitrate Schedute: 1st ouarter
se-rec-type se-code avaiI sanpoint setter-id totatdepth aquifer
SGP.T.
**r There ras no recent bacteriotogical' data fourrd. *r*'
*** There xas no inorganic data found. Not required for transient non-cofirunity systems- ***
*** There ras no inorganic data found for the ner parameters. Not required for transient non-corrnunity systems'
******************* N I TRATE /N I TR I TE *********************
****** atl resutts expressed in mg/|, or pgn i*i*********
** llCLs are 10.0 1.0 10.0
sanptedate nitrate-n nitrite-n no3-noZ-n se-id-1 se-id-2 se-id-3 se-id-4 se-id-5
01/27/95 1.50
01/23/96 3.56
0.00 1 .50
0.00 3.56
*r* There uas no Iead/copper tap nnnitoring data {ound. Not required for transient non-cofirunity systems'
*** There ras no radiotogicat data found. Not required for transient non-cofirunity systems- ***
*** There Has no corrosivity data fouM. ***
*** There uas no trihalornethane data found. Required for conm.rnity systems serving 10,000 or more onty' ***
*** rhere Has no phase t VOc data found. Not required for transient non-cormunity systems. ***
There ras no regutated organics data found. Not required for transient non-cormunity systems' *t*
fhere nas no unregutated organics data fourd. llot required for transient non-coflrunity systems' ***
ri* There Here no chemicat check sanpte tracking records found' ***
*tt*******t******** vlolATloNs - ( Bact and Turbidity ) ***r*****t***r*
BEG-CS{PLI E}TD-COI.IPLI VIOL-TYPE COilTAI'IINAT REASAilPLES VALIO-SA}I RESULT
001
001
flA( l ll \uso
nEs$JFcE
ElslNiERllp
tllc
I,ICL VIOLAT ENF DATE TYPE-LETR EPA-COOE
07tO1/91 09/30/91
0?t01/96 02/29196
05/01/96 05t31/96
3100
31 00
31 00
nitrate ftm 1993
nitrate ftm 1994
?3
?3
23
1
1
1
0
0
0
0 - 00000000
resu I t
0.00000000
0.00000000
o.o0ooo000 11/20/91 1
03/29/96 1
06/2r/96 2
0.00000000 03/06/95 1
o.oooooooo 03/06/95 1
JE
SFJ
SFJ
o
o
*r*********** cHEt{lcAL vIoLATIONS ***********t******
beg-cornpt i end-corpt i viol,-tyPe contaminat reqsanptes vaI id-sam
o't/o1tg3 12t31/93 03 1040 1 o
01/01/94 1?/31/94 03 1040
**********i*r*r** ENFORCEIIENT ACTIONS for CHEHS **t******t*
**** SFJ = viotation letter - SoX = nor in corptiance ****
enf-date epa-code type-tetr coilnents
nc l.-vi o l, at enf -date type-l et r epa-code de t ete
SIA
SIA
01/27/95 sor
01t27/95 sor
*** There rere no state monitoring viotations found'
*r* There are no outstarding enforcement orders' *t*
a Please Note:l,lT = Not Tested
llD = llone Detected
BDL = Betor Detection Limit
< syr$ol for less than
na = Not Appticabte
GLI = ground Hater
Sll = surface Hater
GLn ISll = ground Hater urder the inftuence of surface vater
l,lCL = maxim.rn contaminant leveI
voc = votatite organic chemical
Sl,lTR = surface Hater treatment rute
o
o
o
o
o
a
o
o
o
o
a
o
a
a
o
o
a
Report Date: 03/19/98
Contact: Hamer, l'lari tYn
contact Phone: (970)876-5768/
Operator: Reed, l'li tton
operator Phone: (970)858-7Uz
Resident PoPr.rtation: 'l 15
ilon-Transient PoPUtation: 0
Transient PoPltation: 0
Service Connections: 31
r***i******* s0uRcE It'lFoRl.lATION
se_id srcnun src
001 tl01 llet t
COLORADODEPARTI,IENTOTPUBLICHEALTHANDENVIRO}'II'IENT
Corptiance l{onitoring and Data l'lanagement Unit - tJoCD
Note: corputer data is atrays subject to error. If data apPears unusuat or questionaP+9' .\jl ,'...j.
prease confirm the varidity rith the Drinkins l,ater Prosra* ". <sost frffiu},
' \, e*''D)
UATER ouALrry DATA FoR rD 123518 Iilil",;,H:T:* w I\h( l.'3
'$l'J
195 Honevsuckte cir
^rocEgltcIINEEfltS$Srruita, co 8tsz1
BEF$FC
county: Garfietd
Active Status: Active
Activation Date: 0/
System Begin Date: 0/
System TYPe: CotmlnitY
Systern Source Type: Ground tJater
OPen Year Arourd
** r ***t***** t*t***tt* * ***t
Disinfection llaiver ? No
Bacts Required: 1
Bact Cycte: ilonthtY
Nitrate Schedute: 3rd Quarten
Chemicat Schedute GrouP: 3
Inorganic Schedute: 3rd Quarter
Radiotogicat Schedute: 3rd ouarter
Organic Schedute: Routine - 4 Quanters
se-rec-type se-code avait sanpoint setl^er-id totaldepth aquifer
s G P 'I' 140 Roaring Fork
****tl**************** RECEIIT BACTER I OLOG I CAL **tt*********************
***g=g6fg ***** U=UnSafe ***** N=lnVatid**r*
sanp-date tyPe testmeth quantity tcjres feSres invaIid
1s
1s
1s
1s
1s
1s
1s
1s
1s
1s
1s
1s
1s
1s
1s
01/06/97 r m
02/03/97 r m
03/05/97 r m
04/07/97 r m
05/05197 r m
0611'1197 r m
07/07/97 r m
08/04/97 r m
09/08197 r m
10/08/97 r m
11104/97 r m
12101197 r m
01/05198 r m
02/02198 r m
03/09198 r m
***i***i***** oRIGINAL IIIORGAIIICS **************tt*****t**t**
****** atl resutts and l{CLs expressed in mg/t or Pgn **t****
** lilcLs are 0.05 2 0.005 0 . 1 1-0 na 0.002
SAIiPLEDATE ARSENIC EARIUl,l CADl,llUl,l cHROtitlult FLUORIDE LEAD t'lERcuRY
o o5tz}/86 o.ooo 0.000 o-oooo0 o.oooo 0.250 0'0000 0'00000
o8to7t8g0.oooo.ooo0.ooo7o0.00oo0.4600'00300'00000
osto4tgz 0.000 o.06 o.ooo2 0.004 o-26 0'001 0'00000
08/10/94 BDL BDL BDL BDL 0.36 O.OO9 BDL
0.05 na
SELENIU}I SILVER
0.000 0.0000
0.002 0.0000
0.001 0.0000
0.002 llT
0.000 )rT
na
SOO IUI,I SE-ID-
25 001
18 001
?9.2 001
16.8 001
17.4 001
1 SE-ID-2 SE-ID-3 SE-ID-4 SE-ID-:
a
o9to3tg7 0.ooo o.ooo o.oooo 0-000 0-32 0'000 0'0000
a
o
o
o
a
a
o
riiril**r*lli* llEll INoRGANIC PARAI,IETERS t****tt*t*l*t***t**
*tt*** atI resutts expressed in ots/t or Ptln *tttri*ltr****
******t***ttr* TESTING BEGAN JAN 1, 1995 ***tt**ttttt***i**
** llcLs are 0-006 O.OO4 0.2 0.1 na 0'002
SAI,IPLEDATE ANTIIIONY BERYLLIUI'I CYA}IIDE IIICKEL SULFATE THALLIUI'I COTIPOSITED SE-ID-1 SE-ID-2 SE_ID-3 SE-ID-4 SE-ID-5
08/10191 BDL BDL
09/03/97 0.00
BOL }IT 371 . O BDL .F. 001
o.ooo o.ooo 333 0.000 .F. 001
********i***t****** N I TRATE/tl I TR I TE t****fi******r*******
*r**** att resutts expressed in ,g/t or pgn *tt*it******
*r ilcls are 10.0 1.0 10 .0
sanptedate nitrate-n nitrite-n no3-no2-n se-id-1 se-id-2 se-id-3 se-id-4 se-id-5
05tz}tffi 0.00
08t07/89 0.90
05/04/92 1.75
08t10t94 1.06
ogt'.t0/94 1.06
07/24t95 1.84
11/20/96 1.83
09/08/97 0.65
lrr 001
1.06 001
1.06 001
001
001
001
NT
NT
001
001
0. 001
0.00
0 .00
0.00
0.00
0 .00
1.84
1 .83
0.65
******************* LEAD,/COPPER TAP I,IONITORING DATA ***********
***** levets are 90th percentil'e I'evets expressed in mg/[ *****
beg-coryl.i end-colpti pb-gOth cu-90th
07/01/93 12/31/93 0.000 o.01
01/01/94 06130/94 0.001 0.02
01to|t95 1213'.t195 0.00'l 0.81
01to1/97 12/31/97 0.005 0.01
o1/01/00 12/31100
ii**************** RAD I OLOG I CAL **********t*****t********
r*** atl resutts expressed in pci/t, excePt TS in mg/[ r***
PLANTNU}IBR SAI,TPLEDATE SA}ITYPE ALPHA ADJ-ALPHA BETA RA226
1 04/061u 0.0 0.0
1 02 t15189 G 0.0 0.0
u01 1',1/21/95 HS )lT
!101 09/24196 HS NT
0.0 0 .00
0.0 0.00
HS <1
HS <1
RA228 RA??6-228 URANIU'.I TS
0.00 0.00 3.0 0
0.00 0.00 3.0 1460
NT NT <2 930
lur NT 2 1000
RADOIJ-222
NT
NT
***** atI units are mg/[ excePt Langtier,
sanptedate Iangtier tot-atk ca-hard ph
08/09/89 -.?18 278 538 6.8
pH, ard teoP ****
tds xater-tefiP chtoride sutfate
1050 53 F
a
a
*** There ras no trihalomethane data found. Required for conmlnity systems serving 10,000 or more onty. ***
***************t** Phase MC t S ************t****
ptantnirbr ptantname sanptedate detected
1 l4ountain lleadors Traiter Park 02/'11/91 )lo vocrs detected'
*************** REGULATED PHASE l/lllV oRGANtCS r*i**r*********
Note: Inctuded as part of Phase IIlV organics as of 1/1/93'
Refer to fil,e for information on detects'
Sources:001 09127193 CanPosited: T rith: 123188 r** There Here no regutated detects in this sanpte. ***
o
o *** There Here no regutated detects in this sanpte' *tt
Sources: 001 03/20/95 Curposited: F
o
o
a
o Sources:
i*fi**r*r***r** UNREGULATED pHAsE I/lllv oRGANIcS ***tr*ii***t*** Note:
Og/27tg3 conposited: T rith: 125188
Detections of Trihatomethanes are not printed'
l{onitoring is required. }lo standards have been set'
r** There Here no unregutated detects in this safipte' *rt
Corlposi ted: F i*i There rere no unregutated detects in this sanpte'
Sources: 001
o
*** There raere no chemical check saflpte tracking records found' r*r
*r* There Here no bacteriotogicaI or turbidity viotations found' ***
r***rr******* cHEtllcAL vIoLATIONS *t*******t********
beg-corpt i end-corpt i vi ol,-type contami nat reqsanptes va I i d-sam
olt}l/g3 12131t93 03 1O4O 1 0
**t******t***fi*i ENFORCEIIEIII ACTIONS fOr GHEHS ****tf**i**
**** SFJ = viotation tetter - SOX = nor in cooptiance t***
enf-date epa-code type-letr cofinents
08/10/91 sox
*********** STATE titQNIIORING VTOLATIONS t**i***t********t*
reqsa[ptes vatid-sarn enf-date tyPe-tetr epa-code
resu t t
0 .00000000
ncl.-viotat enf-date type-tetr epa-code detete
o.oooooooo 03/06/95 1 so6
beg-conpt i end-corpt i vi ol-type contami nat
07/01/97 1?/31/97 03 1038 1 0 12/?2/97 9FJ
a *** There are no outstarding enforcement orders' *tt
Ptease Note:llT = Not Tested
NO = llone Detected
BDL = BetoH Detection Limit
< sylbot for less than
na = Not Appticabte
GIJ = ground xater
sLl = surfsce Later
Gl.JutSt = ground xater under the inftuence of surface xater
HCL = maxim.rn contaminant levet
VoC = votatite organic chemicaI
STJTR = surface rater treatment rute
a
o
o
o
t
o
a
o
a
a
o
se_
P
s
s
s
Report Date: 03/19/98
Contact: Evens, Jon 1st
Contact Phone: (970)963-3140
Operator: Evans, Jon zrd
op€rator Phone: (970)625-2559
Resident PoPrlLation: 250
llon-Transient PoPutation: 0
Transient Pogltation: 0
Service Connections: 93
coLoRADoDEPARII,IENToFPUBLIcHEALTHANDENVIRoIIIIENT
Corptiance l'lonitoring ard Data l4anagement Unit - tJoCD
Note: Collputer dat6 is atrays subject to error' If data apPears unusual or
ptease confirm the validity rith the Drinking l,rater Program at (503) 6l
HATER AUALITY DATA FOR ID 123333 H Lazy F ,{HP
ATTN: John Evans
412 East 4th St
Rifte, Co 81550
county: Garfietd
Active Status: Active
Activation Date: Ol
System Begin Date: 0/
System TYPe: CoflrunitY
System Source fYPe: Ground l''ater
OPen Year Around
**************ttt***t**i**
nAI( d 3 ulo
nEsoncrEItctt€B|8
ttE'
Disinfection l,Jaiver ? No
Bacts Required: 1
Bact Cycte: l{onthtY
Nitrate Schedute: 1st Quarter
Chemical, Schedute GrouP: 2
tnorganic Schedute: 1st Quarter
Radiotogicat Schedute: 1st ouarter
organic Schedute: Chaffee/Lautenberg
na
soolul,l SE-ID-1 SE-IO-z SE-ID-5 SE-ID-4 SE-ID-5
11 001
21 001
4 001
9 001
t*i*******t*
se_id srcntm
001 Ink0l
002 1,01
003 u02
004 rJ05
SOURCE INFORITATIO}I
src
Tank
Hel, t #1
rel, l. #2
vett fj
rec-type se-code avail, sanPoint setter-id totatdePth aquifer
P .T.
P .F. 80
P .F. 80
Z .F. 80
o
G
G
G
01/15/97 r m
OZtZS/gl r m
03/25/97 r m
04115/97 r m
04/24/97 r m
05/27197 r m
06/24/97 r m
07/?8/97 r m
08/14/97 r m
09/29197 r m
101?9197 r m
11118/97 r m
12/16197 r m
01/19/98 r m
02/24/98 r m
*t*t********t****t*** REcEllT BACTERIOLOGICAL *****r***t*t*r****i**t***
***s=g6fE ***** U=UnSafe ***** N=lnVatid****
sanp-date tyPe testmeth quantity tcJrres fepres invatid
1s
1s
1s
1s
1s
1s
1s
1s
1s
1s
1s
1s
1s
1s
1s
*********t*** oRIGIIIAL IIIoRGANICS ttttt**t****tlt****t*t*t***
****** atl resutts and tlcLs expressed in mg/t or Pptn *******
r* HCLs are 0.05 2 0.005 0-1 4.0 na 0.002
SA}IPLEDATEARSENICBARlUt.tcADt,lIUt,|cHRol,lIUl,|TLUoRIDELEADHERCURY
12t18tr o.oo0 o.o0o o.o0ooo 0.0000 0'300 0'0061 0'00000
o5tr/,t88 O.OOO O.0OO O.OOOOO O.O0OO O'240 0'0050 0'00000
o8tz2t8g o.ooo 0.390 o.ooooo o.0ooo o'580 0'0000 0'00000
os/o;tg? 0.000 o.o4 o-ooo3 0.003 o'24 0'001 0'00000
0.05 na
SELENIUI,I SI LVER
0.000 0.0000
0.000 0.0000
0.000 0.0000
0.000 0.0000
o
04/15/93 0.002
08/10t94 0.000
01/?5/95 BDL
02t06/96 0.000
0.06 0.0000 0.000
0.00 0.0000 0.002
BDL 0.000/t BDL
0.00 0.0000 0.000
o.o0o 0.00000 0.002
0.007 0.0000 0.000
BDL BDL BOL
0.ooo 0.0000 0.000
0.24
0.33
0.14
0.39
NT
NT
NT
ltT
7 .7 001
7.6 001
16.0 001
8.4 001
o
o
*********tl*** NEt, INORGANIC PARAiIETERS **t*t*rt*t*********
****** att resutts exPressd in mg/t or Ppm **r*t*****i***
*i************ TESTING BEGAN JAN 1, 1993 **li*tt**t*******t
** l,lcLs are 0.006 O.OO4 0.2 0.1 na 0'002
SAMPLEDATE ANTI}IO}IY BERYLLIUT'I CYANIDE NICKEL SULFATE THALLIUI'I CO'IPOSITED SE-ID-1 SE-ID-z SE-ID-3 SE-ID-4 SE_ID-5
04/15/93 O.OOO 0.ooo 0.000 0.000 314 0.000 't'
o8/1}tg4 0.ooo o.o0o 0.000 0.000 165 0.000 'F'
01/25/95 BDL BDL BDL BDL 333 BDL . F.
02t06/96 0.000 0.000 NT 0.002 158 0.000 . F.
*****r************* N I TRATE/N I TR I IE ******tti************
****** atl resutts expressed in mg/t or pFn r*t*********
** llCLs are 10.0 1.0 10 .0
sanptedate nitrate-n nitrite-n no5-noz-n se-id-1 se-id-2 se-id-5 se-id-4 se-id-5
001
001
001
001
1?/18/U 0.00
05/04/8 0.00
08t22/89 0.70
05t04/92 0.408
04/15/93 NT
02/23/94 1.29
08/10/91 0.42
01/25/95 0.31
02/05/96 0.17
01/09/97 0.21
llT 001
NT OO1
NT OO1
lur 001
NT OOl
1.29 001
0.42 001
0.31 001
0.17 001
0.21 001
0.0 0.0
0.0 2.2
1NI
0.003
NT
BDL
0.00
BDt
0.00
0.00
**r*************i*t LEAD/COPPER TAP I,IOIIITORING DAIA t******t***
***** tevets are g0th percentite levets expressed in rE/t *****
beg-carpti end-corpLi pb-90th cu-gOth
07to1/s3 12t31/9t 0.003 0.02
01/01/94 06t30/94 o.ooo o.03
01lo1t95 1?/31/95 o.ooo 0.23
01to1/96 12/31t96 o-01o 0.53
01/01/99 12/31/99
****************** RAD I OLOG I CAL t*********i*t*ti*********
*i** atl resutts expressed in pCi/t, excePt TS in mg71 ****
PLANT}IUI,IBR SAI,IPLEDATE SAMTYPE ALPHA ADJ-ALPHA BETA RA2Z6 RA228 RA2?6_?28 URANIUI,I TS RADON-222
o.oo 0.00 0.0 0
0.00 0.00 2.2 590
NT NT NT Z9O ilT
1 09/04/85
1 05/14190 G
Ink0l 01/?4/95
0.0 0.00
0.0 0.20
1 llT
***t*******tt***** coRRoslvlTY ***tt******tt*************
***** att units are mg/t except Langtier, pH, and teql ****
sanptedate tangtier tot-atk ca-hard ph tds Hater-tenp chtoride sutfate
o8t24t8g -.810 ?32 251 7.0 544 55 F
*** There ras no trihatomethane data fourd. Required for conm.rnity systems serving 10,000 or more onty' ***
*****r************ Phase I vocts ****t*****i***t**Note: lnctuded as Part of Phase lllv organics as of 111/93'
a Refer to fite fon information on detects'
ptantnulbr Ptantname
1 HLAZYFI4HP
sanpl.edate detected
02/11/91 )lo voc's detected.
o **r******r***** REGULATED PHASE I,/lllv oRGAlllcs ***************
Sources: 001 09t27/g3 CorPosited: T rith: 123'19 r** There Here no regutated detects in this sanpte' ***
Sources:001 10t?2/97 Conposited: F *** There Here no regutated detects in this sanpte' ***
o
r*ti*********t* UNREGULATED PHASE I/l I/V ORGANICS ************i**Note: Detections of Trihatonrethanes are not printed'
Sources:001 Og/27/93 corposited: T rith: 123519
l{onitoring is required. ilo standands have been set'
*** There Here no unregutated detects in this sanpte' **i
10/?2/97 Corposi ted: F *** There Here no unregutated detects in this sarpte' *il
a
o
a
o
a
o
o
o
o
o
o
Sources:001
o
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*tr********* cHECK SAMPLE DATA *i**r*i******ii*r*tt*****r
SE-ID SRCNUM SAI,IPLEDATE PARA}TETER PARA-RE SLT
OO1 Tnk0l O1/24t95 Tetrachtoroethyl,ene <0'5
il********** CHECK SMPLE TRACKIIIG INFO *t*ri***t*t***t
Parameter: Tetrachtoroethytene 127'18-4 2987
Source: 001 InkOl H Lazy F llHP xater tank
Check sanpte Ietter date: 01/20/95
Originat sarpte datez 09/27/93 Resutt: BDL ug/t
l4CL Viotation Estabtished ? N
lras presence of contaminant confirmed ? I
Check 1 resutt: <0.5 uslt 01 /24/95
*r*Theret.erenobacteriotogicaIorturbidityviotationsfound.i**
ir* 16u1" rere no chemicat viotations found. r**
*** There rere no additionat chemicat enforcement actions found' ***
**r There Here no state monitoring viotations found' *i*
*** There are no outstarding enforcement orders' **
Ptease Note:NT = Not Tested
ND = tlone Detected
BDL = Betor Detection Limit
< spbol for less than
na = Not Appticabte
Gll = ground Hater
Sll = surface rater
GtJuISu = ground Hater uMer the inf tuence of
l,lCL = maxirr.rn contaminant [eve[
VoC = votatite organic chemical
SIITR = surface xater treatment rute
surface uater
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Report Date: 03/19/98
Contact: !Jigger, Kurt
contact Phone: (970)915-7771 / <ll,
operator: tligger, Kurt
Operator Phone: (970)945'5824/ <H)
Resident PoP,utation: 1
llon-Transient PoPutation: 0
Transient PoPutation: 88
Service Connections: 1
************ souRcE INFORI,IATION
se_id srcnun src
OO'l t,01 llet L
o
COLORADODEPARTIIE}ITOFPUBLICHEALTHANDENVIRONI'IE}IT
Conptiance t{onitoring and Data Nanagement Unit - UQCD
Note: Coflputer data is alxays subject to error. If data appears unusuaI or questionabte'
prease conrirm the vatiditv Hith the Drinkins r''later Prosram at (303)'lmtUt,if(l$
r,rATER ouALIrY DATA FoR ID 223718 -
;:ilt;;T:*""^t rlA( z 3 1ug0
P0 Box 1985
Gtenrood SPrings, Co 81601
county: Garfietd
Active Status: Active
Activation Date: Ol
System Begin Date: 0/
System f ype: Transient ilon-Cofiruni ty
System Source TYPe: Ground [Jater
OPen Date: 01/01
Ctose Date: 12l31
**** ** * t*** ***************
se-rec-type se-code avait sarnpoint setl'er-id totatdepth aquifer
s G P .T. 98
RESOUBCE EN T.IEEFI}{G IT€.
Disinfection Uaiver ? No
Bacts Required: 1
Bact cycte: t'lonthtY
Nitrate Schedule: 1st Quarter
t***************t**** RECENT BACTERIOLOGTCAL *************************
r**S=Safe ***** U=UnSafe t*tt* N=tnVatid****
sanp-date type testmeth quantity tcjres fejres invatid
1s
1s
1s
1s
1U
1U
1s
'l s
4s
1s
1s
1s
1s
1s
1s
1s
1s
01/08/97 r m
02/05/97 r m
03/04/97 r m
01/03/97 r m
05114197 r m
05/?8/97 A m
06/2?/97 r m
06123/97 r m
06/24197 r m
07116197 r m
08/27197 r m
09126/97 r m
10/1r/97 r m
11127/97 r m
12108197 r m
01114/98 r m
02101/98 r m
*** There Has no inorganic data found. llot required for transient non-cofimJnity systefils- *r*
*** There ras no inorganic data found for the neH parameters. l'lot required for transient non-cofirunity systems'
*******rr**r***r*** N I TRATE,/N I TR I TE *l**t******t*t*******
****** atl resutts expressed in mg/t or Pgn ***tt*******
** llCLs are 10.0 1.0 10.0
saoptedate nitrate-n nitrite-n no3-no2-n se-id-l se-id-2 se-id-3 se-id-/' se-id-5
06t15187 0.00 NT llT 001
a
o
03/0?'l)4 NT
03/08/94 l{T
01/24196 NT
NT
llT
NT
<0 .5
BDL
<0.5
001
001
001
o
*r* There ras no tead/copper tap rcnitoring data found. xot required for transient non-comrunity systecs' r**
il* There Has no radiotogicat dsta found. t{ot required for transient non-coflrunity systems' ***
*** fhere Has no corrosivity data found. *fi
*r* There ras no trihatonethane data fourd. Required for corm.lnity systems serving 10,000 or more onty' ***
*r* There Has no phase I VOC data found. )lot required for transient non-coflrunity systems' ***
*** There tas no regutated organics data fotl,d. llot required for transient non-coflrunity systems' **i
r** There Has no unregutated organics data fourd. ilot required for transient non-com.rnity systems' ***
*** rhere Here no chemicat check sarpl.e tracking records found. *r*
*****r**r*********r VIOLATIONS - ( Bact and Turbidity ) *ri***********i
8EG-COI4PLIE}ID-COI,IPLIVIOL-TYPECONTA}II}IATREOSAI4PLESVALID-SAI'IRESULTI'ICL-VIOLATENF-DATETYPE-LETR
o1/01t92 O6lSOlgZ 23 31OO 1 o 0'oooooooo o'ooooo000 08/10/92 1
1Ltl1tg2 121311s2 23 31OO 1 o o'oooooooo 0'00000000 0?/03/93 Z
o1to1t91 O3t31ts4 23 5100 1 o 05t01191 1
,loto1tgi12l31/g42331oo1oo.ooooooo0o.ooo0o00001/27/952
10101/96 1Ll31ls6 ?3 31OO 1 o 11/25/96 1
o5to't/97 O5t3'.t/s7 21 31OO 06117/97 t4
o5to1tg7 O5t31tg7 22 3too 06/17/97 n
********t**** cHEtllcAL vloLATIOllS *******t****i*****
beg-conpti end-conpti viot-type contaminat reqsanpl,es vatid-sam resutt mct-viotat enf-date tyPe-l'etr
o1/011g312/31tg303104010o.ooooooooo.oo00000003/06/951
o1to1ts5 12/31/s5 03 1038 1 0 01103/96
***i*******i***** EllFoRcEttENT ACTIOIIS for cHEils *****r****t
**** SFJ = violation letter - SoX = nol in conptiance ****
enf-date epa-cde type-tetr comnents
03/08/94 SoX
01/24/96 sor nitrate/nitrite ftm 1995
EPA-COOE
SFJ
SFJ
SFJ
SFJ
SFJ
SFJ
SFJ
epa_code det
s06
SFJ
*** There Here no state monitoring viotations found'
*** There are no outstanding enforceflEnt orders' ***
Ptease Note: llT = Not Tested
llo = ilone Detected
BDL = Betor Detection Limit
< sYnbot for tess than
na = Not APPIicabte
Gl,, = ground Hater
Su = surface Hater
Gllt lstl = ground tater urder the inftuence of surface Hater
llCL = maxim'm contaminant levet
VoC = votatile organic chemical
SIITR = surface Hater treatment rute
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ATTACHMENT F
FEBRUARY 28, 1998 LETTER FROM
RESOURCE ENGINEERING, INC.
O &IIEII'IIllTalaITIII,IIEI
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FIES,JUFIGE
ENGINEEFIING
Los Amigos Ranch PartnershiP
c/o Greg Boecker, Ranch Manager
2929 CountY Road 1 14
Glenwood Springs, CO 81601
RE: Los Amigos Ranch ISDS lmpacts
INtr
February 28, 1998
Dear Greg:
This letter summarizes an opinion of the potential impacts to the regional groundwater
regime by ISDS systems proposed for Los Amigos Ranch Filings 6 - 10.
SUMMARY OF OPINION
It is the opinion of Resource Engineering, lnc. that the risk of groundwater
contaminationr as a result of the proposed ISDS systems is remote. There is a
probability that the nitrate level in the groundwater under and adjacent to Los Amigos
hanch will slightly increase as a result of the ISDS systems. However, unless existing
nitrate levels are already approaching drinking water limits the probability of the
incremental flow from Los Amigos Ranch increasing nitrate to a level of concern is
slight.
This opinion is been based on; 1) review of the proposed development including
location and density of the development, 2) review of a Preliminarv Geotechnical Studv.
drfirid Court, Cotorrdo, prepared by Hepworth-Pawlak Geotechnical, lnc. and dated
F"Ur*rV 14, 1997, 3) review of Sorino Vallev Water Resources and Water Riohts,
prepared by Wright Water Engineers, May 'l 977, 4l review of the Colorado Division of
Water Resources water well data base, 5) verbal communication with Mr' Wayne
S,helton and Mr. Bodie Collins, water well drillers both familiar with the area, 6) verbal
consuttation with Mr. Edward O. Church, PE of E.O. Church, lnc., Engineers and
Geologists and 7) professional knowledge of the area.
The opinion presented here is based on a limited amount of hydrogeologic information.
Actual conditions may vary from conditions concluded herein. Specific determination
of the hydrogeologic conditions is beyond the scope of this document and would
require extensive and costly field investigations.
O
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o lGroundwater contamination for purposes of this opinion is defined as an increase in the
nitrate level of the groundwater underlying Los Amigos Ranch and surrounding propertles to a level
;";; the drinking water standard oi tO mgltiteris establisheci by the Colorado Department of
Healtn and Environment and the U.S. Environmental Protection Agency.
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Los Amigos Ranch PartnershiP
cio Greg Boecker, Ranch Manager
Page 2
SITE DESCRIPTION
February 28, 1998
Los Amigos Ranch is located approximately 5 miles south of Glenwood Springs as
shown on Figure 1. Filings 6 -10 will consist of 164 single family lots on 503.575
acres (3.07 acres / lot) and 4 rural residential lots of 223.556 acres. lncluding open
space and roads there is a total of 1,703.058 acres in the development. The density
The proposed development is located on a rolling upland approximately 800 to 1,000
feet above the Roaring Fork River to the west. Spring Valley is located to the east of
the development. Vegetation on the site is predominantly sage and pinyon-juniper with
grass understorY.
GEOLOGIC SETTING
The near surface formation at Los Amigos Ranch P.U.D. is geologically recent basalt
flows. Beneath the basalt lies the Maroon Sandstone formation or, near the south edge
of the property the Eagle Valley Evaporite formation. A general geologic cross section
shown in Figure 2. The Maroon Formation dips steeply away from the Roaring Fork
River valtey. To the east of the site lies Spring Valley formed of alluvial / lacustrine
(lake) deposits overlying the Maroon Formation. The formations underlying the property
are described in detail in the February 14, 1gg7 Hepworth-Pawlak Geotechnical, lnc.
rep ort.
GROUNDWATER OCCURRENCE
Groundwater occurrence in the vicinity of Los Amigos Ranch is quite complex. The
depth to groundwater and the ability to develop groundwater varies dramatically over
a short distance. Three distinct areas, each with differing groundwater conditions
exist. These are 1) the upland area where the majority of the Los Amigos P.U.D. will
be located, 2) Spring Valley and 3) the Roaring Fork Valley' Each of these areas is
discussed below.
Los Amigos Ranch Area
The geologic setting of Los Amigos Ranch and the area to the north is basalt flows over
tn" u-"rt"riy dipping Maroon formation. Numerous dry wells have been attempted to
the north of Los Amigos Ranch ranging from 3OO to 8OO feet deep' That is, no water
table was encountered. These *"il= lenerally penetrate through the Basalt and into
in" tVtrroon Formation. Depth to groundwater in the Los Amigos Ranch development
area may generally range from 3OO feet to 600 feet or more as shown on Figure 2'
ifr"ru dry wells indicate that the basalt and Maroon formations are fractured' allowing
them to drain readilY.
o !!!::EFqnt JPCEatltallLUUuaaaltttlrr
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Los Amigos Ranch PartnershiP
c/o Greg Boecker, Ranch Manager
Page 3
February 28, 1998
There is one reported well in the Los Amigos Ranch development area that encountered
water. This well is reportedly 1OO feet deep, with a static water level of 60 feet and
produced 4 gallons per minute. lt is our opinion that this well encountered a localized
perched ,quif.r condition that exists because of relatively permeable basalt overlying
a localized area of less permeable Maroon Formation. Based on our knowledge of the
area we believe it unlikely that this well could sustain 4 gpm indefinitely. The present
,un"g".unt of Los Amigos Ranch has no knowledge of this wells existence and it is
not in use.
Spring ValleY Area
Spring Valley to the east of Los Amigos is relatively flat valley characterized by
ailuviit/lare deposits as much as 3oo feet thick or more. Presumably the valley is
underlain by Maroon Formation dipping easterly. The Spring Valley area is recharged
uf runott from the east. Several springs and Landis Creek on the east side of the valley
feed the aquifer. There are no known sources feeding Spring Valley from the west.
The static water level in Spring Valley ranges from 100 + feet in the south end of the
valley to the ground surface in the north end of the valley. lnvestigators in the past
(Wright WateiEngineers) have opined that Spring Valley effectively fills and spills down
h-"a
-Cunyon Creek at the north end of the valtey during runoff . Once runoff is over,
and the ievel drains below the natural outlet into Red Canyon Creek, the valley is
effectivety kept full by the major recharge area to the east - northeast'
High capacity wells have been constructed in the alluvium in the south end of Spring
Vu'it.V. These include wells for Colorado Mountain College and Los Amigos Ran:h'
These wells are generally between 200 and 3OO feet deep with static water level
O.pin, ranging from 76 feet to 2OO feet. Further north in Spring Valley low capacity
shallow wells have been constructed.
Shallow wells in Spring Valley contrast with deep dry holes just west of Spring Valley'
iigur"r 1 and 2 show the proximity of producing wells in Spring Valley and deep, c:'y
tries immediately to the west. From this we have concluded that the groundwater
Jo". no* flow from the Los Amigos Ranch development area towards Spring Valley.
in" nyOr"ulic gradient suggests that groundwater moves to the west from Spring
Vutt"y'to*ardsihe Roaring Fork River. ihu gradient indicates that groundwater "leaks"
from the edges and bottom of Spring Valley and into the adjacent and underlying basalt
and Maroon formations.
Roaring Fork River ValleY
Numerous wells have been constructed to support development in the vicinity of
CornaV Road 114 and highway 82. To the south of County Road 114 these wells
o rrl..----rrr-rr-C:::::HE=l.-ur-it-L-rlraalaala
Los Amigos Ranch Partnership
do Greg Boecker, Ranch Manager
Page 4
February 28, 1998
generally penetrate alluvial / colluvial material and extend to the contact with the Eagle
Valley Evaporite. There is a very thin saturated zone on top to the evaporite from
which these welts produce. These wells appear to be recharged from limited runoff
from the Evaporite hillslopes to the east, Cattle Creek and irrigation return flows. lt is
our opinion that there is limited, if any, hydraulic connection between these wells and
the Los Amigos develoPment area.
To the north of County Road 114 in the vicinity of the Highway 82 intersection there
are three types of wells: 1) Roaring Fork River alluvial wells that are generally shallow
and immediatety adjacent to the river and draw water directly from the river, 2) wells
in the Eagle Valley Evaporite ranging from 1OO to 2OO feet deep producing low
quantities of poor quality water and 3) wells in the Maroon Formation adjacent to the
dvaporite. Near the contact between the Evaporite and the Maroon it is possible to
have one well in the Evaporate and another well in the Maroon only a few hundred feet
apart. Generally the wells in the Maroon yield slightly higher quantities of water
primarily due to fractures in the formation. Water quality in the Maroon is poor due to
its proximity to the Evaporite.
The water level in these Maroon and Evaporite wells is generally slightly above the river
level (Figure 2) indicating there is some recharge from the sources other than the river.
It is likely that a significant amount of recharge can be attributed to the nearby
Glenwood Ditch and irrigation to the south although there may be a component from
Spring Valley and the Los Amigos Ranch development area'
BASELINE WATER OUALITY
A limited amount of water quality data from wells was obtained to determine the
baseline groundwater nitrate concentrations in the area. Water quality data was
obtained from the Colorado Department of Health and Environment, Water Quality
Control Division (WOCD) for the wells serving the existing Los Amigos Ranch
development and Colorado Mountain College. These wells are fairly close to each cthc:
near the south end of the Spring Valley. A field nitrate sample was obtained on March
3, 1gg8 from the'Collins Drilling Co. well (Permit #46017-F) located north of the
intersection of County Road 1 14 and Highway 82. The Spring Valley wells : ,:
indicative of the water quality above Los Amigos Ranch and the Collins well is
indicative of the water quality below the Los Amigos Ranch'
The Colorado Mountain College well reported nitrate concentrations rahging from O.1 8
mg per liter to 1.17 mg / liter. The nearby well serving Los Amigos Ranch reported
nitrate concentrations ranging from O.OO mg /literto O.77 mgi liter. These levels are
well below the drinking water standards of 'lO mg / liter'
:::::EEqr-rt rE-EalaaallLUUUlrUrtaataaaatt
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c/o Greg Boecker, Ranch Manager
Page 5
February 28, 1998
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The Collins Drilling Co. well was field tested using a Hach color disk nitrate test kit with
azero to 50 mg / liter range. A sample was obtained from a hose bib afer allowing the
water to run for approximately 30 seconds. The test indicated that no nitrates were
present.
The Collins well is topographically the highest well in the vicinity of the intersection of
County Road 1 14 with Hwy 82. lt is possible that groundwater from wells nearer the
river would exhibit some nitrates as a result of local up gradient ISDS systems.
LOS AMIGOS RANGH ISDS IMPACT
It is the opinion of Resource Engineering, lnc. that ISDS systems in Los Amigos Ranch
are not likely to cause groundwater contamination as previously defined. This opinion
is based on the anticipated wastewater loading rates together with the geologic setting
and groundwater conditions described above.
ISDS Loading Rate
To estimate the potential impact of the ISDS systems a mass balance calculation was
conducted to determine the attenuation of nitrate in the groundwater. The analysis
was conservatively done, including only the recharge from within the 1,700 acre
footprint of the Los Amigos Ranch development area.
a
Based on an ISDS loading rate of 3OO gallons per day per ISDS the average annual
loading of 168 units in the 17OO acre development is 0.4 inches per year. This
compares to an average annual precipitation rate oI 17.7 inches per year in the
Glenwood area'
lf is assumed that 1.85 inches of annual precipitation is deep percolated2, having a
nitrate level of O.O mg/liter and that is combined with O.4 inches of ISDS effluent
having a nitrate concentration of 40 mg / liter3 the resulting nitrate concentration
entering the groundwater will be 7.1 mg / liter. This is less than the drinking water
standards.
This analysis does not include the additional attenuation that will occur as a result of
recharge that takes place from off the Los Amigos Ranch property. We believe that a
significant amount of recharge is occurring as groundwater leaks out of the Spring
2 17.7 inches annualprecipitation less 14 inches assumed ET less 50% of the remaining
3.7 inches lost to surface runoff results in 1.85 inches of deep percolation.
3 From personal communication with Edward O. Church PE cf E.O. Church, lnc., Consulting
Engineers and Geologists, Denver Colorado.
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c/o Greg Boecker, Ranch Manager
Page 6
February 28, 1998
Valley aquifer. This component of groundwater flow under the Los Amigos Ranch
property is likely much greater than the precipitation recharge component. Assuming
that 3OO acre feet of water, having a nitrate concentration of 1 mg / liter leaks from
the Spring Valley aquifer each year and flows under the Los Amigos Ranch property,
the nitrate concentration estimated above would be further reduced to 4.1 mg / liter.
Geologic Setting (Depth to Groundwater)
Groundwater in the Los Amigos Ranch development area ranges from a minimum of
100 feet to as much as 800 feet based on well data. Typically groundwater depth
appears to be more than 300 feet over most or all of the Los Amigos Ranch property.
Because of this depth the effluent plumes from ISDS systems are expected to disperse
and reach the groundwater in a fairly uniform pattern. lt is improbable that
concentrated effluent will reach the groundwater that could result in a localized area
of anomolously high nitrate levels.
CONCLUSIONS
The geology, layout of the proposed development and regional groundwater
characteristics indicate that it is highly unlikely that the Los Amigos Ranch ISDS
systems will contaminate the regional groundwater. The density of the development.
approximately 10.1 acres per ISDS system, ensures that the groundwater loading from
ISDS systems is low. The great depth to groundwater over the site ensures dispersion
of the effluent plumes prior to intercepting the groundwater. Finally, recharge from
Spring Valley aquifer to the east helps to reduce nitrate concentrations by adding
mixing flows to the ISDS effluent.
SincerelY:
RESOURCE ENGINEERING, INC.
,/-, n-
/ohn M. Currier, PE
Water Resources Engineer
JMC/jmc
File filslosamigos.wpd
Attachments
Mr. Dean Gordon, w/attachments
Mr. Ed Church, w/attachments
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CC:
!i::iFESCUtrCEtatlttaita
Resource Engineering, lnc.
909 Colorado Avenue
GLET.I\AIOOD SPRINGSi COLORADO 81601' (970) 94s.6777
SHEET NO.
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