United States
Environmental Protection
Agency
Office of
Emergency and
Remedial Response
EPA/ROD/R06-85,006
March 1985
ERft
Superfund
Record of Decision
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TECHNICAL REPORT DATA
(Please read Instructions on the reverse before completing)
1. REPORT NO. 12. 3. RECIPIENT'S ACCESSION NO.
EPA/ROD/R06-85/006
4. TITLE AND SUBTITLE 5. REPORT DATE
March 22, 1985
SUPERFUND RECORD OF DECISION 6. PERFORMING ORGANIZATION CODE
South valley, NM (IRM)
7. AUTHOR(S) 8. PERFORMING ORGANIZATION REPORT NO.
9. PERFORMING ORGANIZATION NAME AND ADDRESS 10. PROGRAM ELEMENT NO.
". CONTRACT/GRANT NO.
12. SPONSORING AGENCY NAME AND ADDRESS 13. TYPE OF REPORT AND PERIOD COVERED
Environmental Protection Final ROD Report
U.S. Agency 14. SPONSORING AGENCY CODE
401 M Street, S. W.
Washington, D.C. 20460 800/00
15. SUPPLEMENTARY NOTES
'.
16. ABSTRACT
The South Valley Site is located mostly in the inner valley of Albuquerque,
New Mexico. Industrial development in South Valley began in the 1950s. Early
industry included metal parts manufacturing. By the 1960s, organic chemicals
were being handled in the area. Presently, petroleum fuels and various other
organic chemicals are stored and handled within the area. South Valley has been
designated as the State's highest priority site for cleanup due to the presence
of potentially high concentrations of hazardous substances in the groundwater
near the city of San Jose's wellfield.
The selected remedial action includes installing a new water supply well to
replace the capacity of the contaminated well, San Jose No. 6. Total capital
cost for the selected remedial alternative is estimated to be $775,000 with O&M
costs approximately $12,000 per year.
17. KEY WORDS AND DOCUMENT ANAL YSIS
DESCRIPTORS b.IDENTIFIERS/OPEN ENDED TERMS C. COSA TI Field/Group
a.
Record of Decision
South Valley, NM (IRM)
Contaminated Media: gw
Key contaminants: VOCs
18. DIST, JUTION STATEMENT 19. SECURITY CLASS (Tlris Report) 21. NO. OF PAGES
None 38
20. SECURITY CLASS (Tlris page) 22. PRICE
~ None
EPA Form 2220-1 (Rev. 4-77)
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,)
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Title should indicate dearly and briefly the subject ~'overage of the report, and be disl'lay~'d promin~'ntly. S~,t snhtitll', if IIs~'d. in smalkr
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Include ZIP code,
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Indicate interim final, etr" and if applicable, dates covered.
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Enter information not included elsewhere but useful. such as:
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Include a brief (200 words or less) factual summary of the most signifkant information ,ontain~'d in Ih,' I"port. It Ih,. 1"1"'11 <'IlIIlains a
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Prepared in ,ooperation with, Translalion of. I'res,'lIll'lI .lll'OIlI~'I'l'''''l' ..r.
17. KEY WORDS AND DOCUMENT ANALYSIS
(a) DESCRIPTORS - Select from the Thesaurus of Engineerin~ and Sdentilk Terms the proper aulhmit.ed krllls Ihal identify Ihe major
concept of the research and are sufficiently specific and predse to be used as index entries for ,alalngrng.
(b) IDENTIFIERS AND OPEN-ENDED TERMS - Use identifiers for project nam~'s, code names, cljuipment designators, el,. Use 0PCII-
ended terms written in descriptor form for those subjects for which no descriptor exists.
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endeavor, or type of physical object. The application(s) will be cross.referenced with ,el'Ondary I il'lli/(irolll' "S\lgnmeJlI\ thai will rollo"
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~.
Record of Decision
Remedial Alternative Selection
SITE: South Valley, Albuquerque, N.M.
DOCUMENTS REVIEWED
I am basing my decision on the following documents describing the
analysis of cost effectiveness and environmental soundness of initial
remedial alternatives for the South Valley Superfund site:
- South Valley Focused Feasibility Study
- South Valley Focused Feasibility Study Amendment
- Summary of Remedial Alternative Selection
- Responsiveness Summary, including public comments
DESCRIPTION OF SELECTED REMEDY
A new water supply well is to be installed to replace the capacity of
the contaminated well San Jose No.6. The capacity of this well ;s
currently required to provide the South Valley service area with adequate
fire-protection water supply and to prevent possible contamination at
the tap.
DECLARATIONS
Consistent with the Comprehensive Environmental Response Compensation.
and Liability Act of 1980 (CERCLA), and the National Contingency Plan
(40 eFR Part 300), 1 have determined that the installation of a new water
supply well as an initial remedial measure at the South Valley Superfund
site is a cost effective, environmentally sound remedy and is necessary and
feasible for protection of public health, welfare, and the environment
from exposure or threat of exposure to a significant health or environ-
mental hazard. The State of New Mexico requested this measure and has
been consulted and agrees with the approved remedy. The action will
require future operation and maintenance activities to ensure the
continued effectiveness of the remedy. The City of Albuquerque has
agreed to accept all operation and maintenance costs for the operating
life of the well.
1 have also determined that the action being taken is appropriate when
balanced against the availability of Trust Fund monies for use at other
sites. This measure is consistent with any permanent remedy to prevent
or mitigate the migration of a release of hazardous substances into the
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- .'
i8
j
'J .
2
The EPA is currently performing additional remedial investigations/
feasibility studies to evaluate the extent of off-site contamination
and possible source control measures to remediate contamination at the -
South Valley site. If additional remedial actions are determined to be
necessary a ROD wil' be prepared for approval of the future remedial
action. .
cu~~~
Regional Administrator
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SUMMARY OF INITIAL REMEDIAL MEASURE ALTERNATIVE SELECTION
Albuquerque South Valley
--Ma rch, 1985
Site Location and Description
The South Valley Site, shown in Figures 1 and 2, is located mostly in the
inner valley of the Rio Grande River southwest of Albuquerque, New Mexico.
It has been designated as the State's highest priority site for cleanup
due to the presence of potentially high concentrations of hazardous
substances in groundwater near the City's San Jose wellfield.
Site History
Industrial development in the South Valley began in the 1950s. Early
industry included metal parts manufacturing. By the 1960s, organic
chemicals were being handled in the area. Presently, petroleum fuels and
various other organic chemicals are stored and handled within the area.
Although earlier problems with wells had been reported, groundwater contami-
nation was first suspected in 1978 when tastes and odors were noted in a
private well near facilities operated by a chemical distributing company.
Subsequent sampling showed certain volatile organics were present in two
municipal wells - San Jose No.6 (SJ-6) and San Jose No.3 (SJ-3). (See
Figure 2.) These wells were subsequently taken out of operation by the
City. SJ-6 was a very productive and economical source of potable water
for the City and also played a key role in providing sufficient fire
protection. The New Mexico Environmental Improvement Division conducted
a monitoring program (during 1980 through 1982), which indicated ground-
water contamination in South Valley may have a number of sources, including
several industrial operations located in close proximity to the contaminated
we 11 s .
In June 1982 the New Mexico Environmental Improvement Division stated that
the Albuquerque South Valley site is the State's number one priority Super-
fund site. The State requested the site be ranked for inclusion on the
National Priorities list (NPL), under the Comprehensive Environmental
Response, Compensation and liability Act (CERClA), 42U.S.C.~9601 et ~.,
also known as "Superfund." The site made the NPL which was publisned 1n
the Federal Register on December 30, 1982. On August 9, 1983, the Director
of the New Mexico Environmental Improvement Division requested that EPA
initiate Remedial Investigations and Feasibility Studies associated with
the South Valley Superfund site including the resolution of immediate
water supply problems resulting from the shut-down of the contaminated
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San Jose and Associated
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4
The Environmental Protection Agency (EPA) is currently conducting 2 stud-
ies in the Albuquerque South Valley area pursuant to Section 104 of CERCLA
and one study pursuant to Section 3013 of the Resource Conservation and
Recovery Act (RCRA). The EPA studies, which were requested by the Director
of the New Mexico Environmental Improvement Division (NMEID) are as
follows:
o Offsite Remedial Investigation (104 CERCLA)
o Source Control Remedial Investigation (3013 RCRA)
o Focused Feasibility Study (FFS) (104 CERCLA)
The purpose of the CERCLA offsite remedial investigation is to determine the
nature and extent of the contaminated groundwater at the South Valley
site and to gather necessary data to support a study of remedial measures
and to provide long-term monitoring of the contaminated groundwater
system. The objectives of the offsite investigation are:
o Determine the general extent of contamination at the site.
o Oetermine the direction and velocity of contaminant
migration (i.e., groundwater flow direction).
o
Determine the future environment/human health impacts
that may be caused by the contaminated aquifer.
o Develop a plan for a long-term monitoring well and testing
program to assess any long-term impacts on the aquifer.
This investigation is part of the overall effort to identify and control
groundwater contamination in the South Valley area. The offsite remedial
investigation and the FFS are being conducted independently but are
closely related, since SJ-6 draws its water from the same aquifer being
studied in the offsite Remedial Investigation. Phase I of this study is
scheduled to be completed in March 1985.
The primary goal of the source control remedial investigation is to iden-
tify the source or sources which have caused or have the potential for
causing the groundwater contamination at the South Valley site. This
investigation is being accomplished through the implementation of five
RCRA 3013 Orders and one CERCLA Consent Agreement (with the U.S. Air
Force) which were issued during the period of August to October 1984.
The information gathered during this study will eventually result in the
development of remedial measures needed to control releases or potential
releases from contaminant source(s). First phase remedial investigation
results are expected to be submitted for EPA review by June 1985.
The contamination and subsequent shut-down of well SJ-6 has had a drastic im-
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5
by officials representing the City of Albuquerque that water system reli-
ability and fire-protection water supplies were inauequate to serve the
needs of the South Valley service area as a result of the shut-down of
SJ-6. This concern was part of the impetus for the NMEID Director1s
request for EPA assistance filed August 9, 1983. In response to the
Director's request, a Focused Feasibility Study was conducted by EPA
contractor CH2M Hill to determine if an initial remedial measure (IRM) was
required to mitigate potential threats or endangerment to human health,
welfare, or the environment resulting from the shut-down of SJ-6. Appro-
priate remedial measures would be developed to rectify any adverse impacts
identified. The completion date (including public input) for the FFS
including an amendment was March 1985. This Record of Decision addresses
only the results of the FFS associated with initial remedial measures
which must be implemented at the South Valley site.
Current Site Status
A review of the existing data base indicated that samples were taken and
analyzed from private and municipal wells and from monitoring wells
installed by the New Mexico Environmental Improvement Division in and
near the South Valley site. The wells from which these samples were
taken varied in location, depth, and type of installation. Variations in
contaminant concentrations were observed among the wells that were sampled
and were also noted in wells that have been repeatedly sampled. Generally,
contaminants found have been volatile organic compounds. A more detailed
description of these sampling efforts and the results of the analyses are
presented in the Remedial Action Master Plan for the South Valley hazardous
waste site dated July 25, 1983.
The results of samples taken from SJ-6 thru February 1982 are presented
in Table 1. Although these data are limited, they indicate that detectable
levels of volatile organics existed in the wellwater. Also, one sample
analysis detected, but did not quantify, some base neutral compounds in
the wellwater.
In order to develop a strong statistical base within acceptable confidence
limits, additional sampling and analyses were deemed necessary. Therefore,
in April and May 1984, as part of the FFS, a 2 week continuous pump test
with daily sampling was performed on SJ-6. The results of the analyses
of these samples are shown in Table 1.
For the most part, samples collected during the FFS are consistent with
previously collected samples in the types and concentrations of contami-
nants. (See Table 1.) Although the limiting contaminant for air-stripping
treatment alternatives, 1, 2-dichloroethane, was not detected in these.
most recent samples, it should be noted that the two week pump test con-
ducted upon SJ-6 in 1984, during which the samples were taken, followed a
period of two years when the well had been shut down. It is possible that
the contaminant had not been fully drawn into the well's cone of influence
during the 1984 pump test and was, therefore, not detected in recent
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Tabl
ANALYTICAL RESULTS OF SOUTII VALLEY GFOUND",,,-tER SAMPLES FROM SAN JOSE WELL No. 6
!l!! !l.!!L!! !!I!! !!fl!l!! ....~ !L!!!!! !l!! ID18. !lli !lli ~
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-------
7
through 1982 can not be easily discounted. Two indpendent laboratories
detected 1,2-dichloroethane (which has a Recommended Maximum Contaminant
. ~evel (RMCL) of zero in drinking water) in well SJ-6 samples collecterl
on the same day. One of the laboratories has been audited by the EPA
since 1978 and has always p~rformed well. For these reasons, it was
assumed, when setting design criteria for certain treatment alternatives,
that 1,2-dichloroethane, may be present. .
Table 2 presents a summary of statistical information for the data which
were collected on SJ-6. The data in Table 1 show a possible downward
trend with time in contaminant concentrations during the first week of
the most recent sampling period. This trend, as opposed to random scatter,
is largely responsible for the standard deviations of these data. Currently,
there is no known explanation for this apparent trend. Samples collected
and analyzed during the second week of the 1984 pump test of SJ-6 demon-
strated consistency both with respect to types of contaminants identified
and the concentrations of contaminants detected.
Three of the four contaminants detected during the 1984 pump test of well
SJ-6, are suspected carcinogens. EPA RMCL's for these three contaminants
are zero (Table 3). Table 3 also summarizes the excess lifetime cancer
risk associated with ingestion of various carcinogenic contaminants. The
goal of most CERCLA remedial actions is to reduce potential carcinogen con-
taminant concentrations to between the 10-4 and 10-8 risk levels. A 10-6
excess lifetime cancer risk level is typically used. Contaminant concentra-
tions of three of the four primary compounds detected during the April/May
sampling effort exceed the 10-6 excess lifetime cancer risk levels shown
in Table 3 even if dilution by other wells in the San Jose Jose well field
is considered. Therefore, the water quality of SJ-6 would pose a threat to
public health if consumed prior to treatment. Most of the substances,
including the chlorinated ethanes, ethenes, and methanes, which have been
detected during the various analyses of SJ-6 well water to date, are
hazardous substances as defined in Section 101(14) of CERCLA.
The fact that SJ-6 had been taken out of service due to contamination
problems has had a serious impact upon the available fire-protection
water supply in the South Valley service area. Fire protection equipment
purchases and fire-protection strategy development have been based upon
the availability of three million gallons of reserve storage capacity.
Serious fire-protection water supply shortages occurred during the summer
of 1980 when water dedicated to fire-protection was utilized to satisfy
daily demands. Fortunately, no major fires occurred during these condi-
tions. Similarly severe water shortages did not occur during the period
1981 through 1984 due, almost certainly, to the fact that greater amounts
of precipitation were received during the summer months relative to 1980.
Statistics prepared by the Middle Rio Grande Council of Governments of New
Mexico indicate that population increases were projected for the South
Valley area during this same period of time. A year of similar dryness
to that of 1980 would not be unlikely, and it is anticipated that the mag-
nitude of fire-protection water supply shortfalls would be more severe
than the shortfalls experienced in 1980. If a major fire were to occur
in the South Valley area, public health would be threatened by the danger
of fire, as well as the posiblity that SJ-6 would be pressed into service
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Table 2
SUMMARY OF QUANTIFIED CONTAMINANT DATA FOR SAN JOSE WELL NO.6
~linK Prior to Focused Feasibility Study (6/80-2/82)
ontamlnant Samples with Standard
Volatile Organic Range Quantified Mean Deviation
Cont..inant (pg/L) Analyaes Data .!.1!8.ill (J,lg/L)
Methane
Dichloro NO-4 1 4 MIA
Trichloro NO-IO 2 6.5 5
Tetrachloro ND-1 1 1 MIA
Ethane
l,l-Dlchloro NO-lJ 6 8.1 3.6
l,2-Dichloro ND-4 2 2.5 2.1
l,l,l-Trichloro NO-I 1 1 N/A
Ethene
l,l-Dlchloro NO-11 8 9 2.1
l,2-Transdichloro NO-I 1 I MIA
Trichloro MD-21 1 10.4 5
Tetrachloro . ND-16 1 9.1 4.1
Notes:
NO . Not detected.
N/A - Not applicable.
DE/SVLY3/044
Conta.lnant
Range
(PIlL)
Sa8pllnK DurinK Focused Feasibility Study
(4/23/84-5/2/84)
Samples with
Quantified
Analyses Data
Standard
Deviation
(pg/L)
Mean
(J,lg/L)
11-11
2
11
10-16
10-12
5
3
12.4
10.61
o
2.3
1.15
Proposed
EPA
Standards
(pg/L)
o
o
200
o
o
o
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9
Table 3
WATER QUALITY STANDARDS CRITERIA AND DETECTION lIMITS
FOR CONTAMINANTS FOUND IN SAN JOSE WELL No.6
Contaminant
EPA
Recommended
Maximum
Contaminant
Levelsa
(ug/L)
Excess 10-6
Lifetime
Cancer Risk
(ug/L)C
NMWQCC
Regulations
Discharge Onto or
Below the Groundb
(ug/L)
VOLATILE ORGANICS
Benzene
Methylbenzene (Toluene)
Methane
Dichloro
Trichloro
Tetrachloro
o
0.68
10
15,000
o
10
Ethane
1,1-Dichloro
l,2-Dichloro
1,1,1-Trichloro
o
200
0.95
20
Ethene
l,1-Dichloro
1,2-Transdichloro
Trichloro
Tetrachloro
o
o
o
0.25
5
2.8
0.9
100
20
aFederal Register, June 12, 1984 page 24352.
bNew Mexico Water Quality Control Commission (NMWCC) Regulations, as
amended through September 20, 1982.
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10
Enforcement
Notice letters have been sent to all of the identified potentially respon-
sible parties (PRPs) for the site. The PRPs were offered the opportunity
to conduct Remedial Investigation/Feasibility Studies (RIFS) and the
remedy. An administrative order for conducting the RIFS was drafted and
presented to the PRPs, but all declined to enter on consent. EPA then
determined to pursue a three pronged strategy to accomplish remedial objec-
tives at the South Valley Site. As stated previously, those three approaches
were the off-site remedial investigation, source control invest'igations
under RCRA 3013, and the FFS which supports initial remedial measures (IRM).
EPA contractor CHZM Hill is in the process of conducting the offsite remed-
ial investigation. EPA has issued negotiated or unilateral administrative
orders for onsite Source Control investigations pursuant to RCRA ~3013.
These individual source control investigations for each PRP are to be
conducted and funded by the PRPs, and the results are to be integrated
with the results of the offsite remedial investigation.
An FFS and an amendment thereto have been performed by CHZM Hill to invest-
igate remedial alternatives which would mitigate the immediate endangerment
to public welfare posed by the shut-down of SJ-6. EPA has selected the
appropriate IRM from those alternatives evaluated in the FFS and plans
to contact the PRPs and offer them an opportunity to implement the IRM.
If the PRPs decline to implement the IRM and fund moneys are used, EPA
will take cost recovery actions to recover these expenditures.
Alternatives Evaluation
Background
The FFS and FFS Amendment, which are considered as part of the ROD, ad-
dress potential remedial action alternatives which will mitigate fire-
protection water supply shortfalls that have resulted from the shut-down
of contaminated well SJ-6, and prevent contaminated water from reaching
the tap.
This action is being conducted in conformance with the National Contingency
Plan (NCP) Part 300.68 as published in the Federal Register on July 16,
1982. Sufficient fire-protection water supply has not been available on
a reliable basis in the San Jose service area since well SJ-6 was taken
out of service due to contamination by hazardous substances. Part 300.68
(e)(l) of the NCP states:
"In some instances, initial remedial measures can and should
begin before final selection of an appropriate remedial action
if such measures are determined to be feasible and necessary
to limit exposure or threat of exposure to a significant health
or environmental hazard and if such measures are cost effective.
... The following factors should be used in determining whether
initial remedial measures are appropriate:
. . .
(iii) Contaminated drinking water at the tap. (Measures might
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11
. . .
(vi) Serious threat of fire or explosion or other threat to
public health or the environment...."
It should be noted as well that 40 CFR 300.65 (b)(2) provides that
provision for alternative water supplies is an acceptable action to
prevent or mitigate danger to public, health welfare, or the environment.
Further, Section 300.65(a) specifically spells out the threat of contamina-
tion of a drinking water supply, and fire and explosion, as dangers
which warrant immediate response action under 300.65(b). Although these
provisions govern immediate removal actions under CERCLA, and are not
rules governing remedial acHons such as initial remedial measures (IRM's),
the circumstances and rationale are similar since IRM's are generally
addressed in situations with a degree of immediacy. Additional support
for the implementation of IRM's in the circumstances of this case is
found in 40 CFR 300.70(d)(3) which spells out the "provision of new
wells in a new location or deeper wells" as a proper remedial method of
providing alternative water supplies.
The lack of sufficient fire-protection water supply due to the contam-
ination and subsequent shut down of SJ-6 satisfy the conditions for
initial remedial meassures set forth in Parts 300.68 of the NCP. If
Well SJ-6 were conceivably pressed into service to supplement the fire-
protection water supply during peak demand periods to counter possible
fire danger to the public health and welfare, then there is a likelihood
that contaminated water would flow to the taps of South Valley residents
and be consumed. Based upon the concentration of contaminants identified
in well SJ-6 and proportioning the flow capacity of SJ-6 to the total
San Jose well field capacity, it was determined that consumption of water
delivered to the tap would pose a threat to human health. As noted above,
contaminated drinking water at the tap satisfies the conditions for
conducting an immediate remedial measure set forth in Part 300.68 (e)(l)
(iii) of the NCP.
Alternatives Development
The alternatives which were developed in the FFS and FFS Amendment consi-
dered treating the water from the well, taking no action, replacing SJ-6
with a new well at another location, constructing additional storage
facilities and transferring excess capacity to the South Valley service
area from other parts of the Albuquerque water system. Listed below are
the treatment and nontreatment alternatives which were considered as poten-
tial remedial actions at SJ-6 prior to the initial screening:
o Treatment Alternatives
- Physical/Chemical
- Oxidation
- Air Stripping
- Activated Carbon Adsorption
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12
o
Nontreatment Alternatives
- No Action
- Reactivation of Existing Well
- New Well
- Rehabilitation of Aquifer
- Construction of Additional Storage Facilities
- Transfer of excess capacity from other parts of
water system
the Albuquerque
A complete description of the above alternatives can be found on pages 19
through 37 of the FFS and pages 4-1 through 4-14 of the FFS Amendment and
will not be discussed here.
The alternatives mentioned above were sUbjected to an initial screening
process aimed at reducing the number of alternatives to those that are
most suited to meeting the project objective. The criteria used for this
screening process are the following:
o Environmental Effectiveness. Alternatives must
not pose significant adverse environmental effects
and must contribute to the protection of the
public health and environment.
o Engineering Feasibility. Alternatives should
rely on proven technology and should be able to
be implemented effectively for this specific
project.
o Cost. Both capital and operation and maintenance
costs must be considered for each alternative.
An alternative which far exceeds the cost of other
alternatives evaluated without providing substantially
greater public health or environmental benefit should
be eliminated from further consideration.
Alternative Selection Summaries
The following short summaries explain the major reasons why an alternative
was eliminated or retained for further development:
Physical/Chemical Treatment - Physical/Chemical treatment was eliminated
because studies have shown that it would not be effective in removing the
volatile organic compounds found in SJ-6.
Oxidation - All of the developed oxidation processes were eliminated.
The two primary reasons for the elimination of these alternatives, are:
oxidation is not effective in removing the volatile organics and the
costs are very high.
Air ;tripPin~ - Air stripping by packed stripping towers was retained
for urther development. The cost for this alternative is moderate, and
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13
Steam Stripping - Steam stripping was eliminated because of the extremely
high energy costs that would be required, and because air stripping
accomplishes the same objective at a much lower cost.
Activated Carbon Treatment - The activated carbon adsorption alternative
was retained for further evaluation. Even though this alternative appears
relatively costly it has been proven very effective in removing the types
of organic compounds detected in SJ6. .
Synthetic Resin Adsorption - Synthetic resins were eliminated from further
consideration because of process uncertainties. Synthetic resins may
have some potential advantages over activated carbon, but little information
and experience are available on the effectiveness of removing the volatile
organic compounds found in SJ6.
No Action - If no action was chosen. the City of Albuquerque would continue
to serve the area of the South Valley with a less than adequate fire-
protection water supply. In addition. stand-by well capacity in the San
Jose well field has been determined to be inadequate. Occurence of a
major fire in the South Valley area during a period of peak demand would
result in an insufficient firefighting response and a serious threat to
human health. welfare, and the environment. Additionally. there is the
possibility that SJ-6 might be pressed into service to meet such an
emergency with a resulting endangerment of contaminated water at the tap.
Supplying water to the San Jose system with only the existing wells
(excluding SJ-6) would result in a system reliability, which is less than
that recommended in the City Master Plan.
Reactivation of Existing Well - This alternative consists of using SJ-6
without treating the water and operating it to maximize dilution from the
other wells supplying the system. Contaminant concentrations in well SJ-6
would pose a threat to human health if consumed. Therefore this alterna-
tive was eliminated.
New Well - The alternative for constructing a replacement well for SJ6
was retained for further evaluation. A new well would mitigate water
quality concerns. ~nd its cost appears comparable to several treatment
alternatives.
Rehabilitation of Aquifer - Rehabilitation of the aquifer by eliminating
the source or sources of contamination and removing the existing contaminants
is a very desirable long-term solution. Determining the nature and extent
of groundwater contamination. identifying the sources of contamination.
and sUbsequently mitigating the problems are goals of the Remedial
Investigation. Remedial Feasibility Study and Final Remedial Action to be
conducted during 1984-1987. Since aquifer rehabilitation cannot be
implemented in the short term to get SJ6 or its capacity back into service.
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14
Construction of Additional Storage Ca acit - This alternative consists
o e cons rue 10n 0 a 1tiona storage capacity in the Ridgecrest Trunk
such that a sufficient fire-protection water supply would be available
even during periods of peak demand. Based upon Albuquerque water system
records pertainig to the South Valley service area, an estimated 16 MG of
additional storage capacity would be required to overcome production
shortfalls experienced during the peak week in 1980 and still maintain
the necessary 3 MG fire-protection water supply. Due to growth which had
been projected to have occurred in the South Valley service area over the
past four years, even larger storage requirements would be anticipated
for another year having similar rainfall conditions to that of 1980. The
estimated present worth cost of providing an additional 16 MG of storage
in the Ridgecrest Trunk exceeds $3,000,000. This alternative was eliminated
since installation of a new well could just as effectively accomplish the
same objective but at a substantially lower cost. .
Inters stem Transfers of Excess Ca acit - This alternative considers the
poss 1 1ty 0 1vert ng excess capac ty from other regions of the Albuquer-
que water system to the South Valley service area. The availability of
excess capacity in the upstream zones of the Ridgecrest Trunk, which is
served by the San Jose well field, as well as excess capacity of other
trunk lines was investigated. Analysis of past water system records
indicate that upstream regions of the Ridgecrest trunk and trunk lines
adjacent to the Ridgecrest trunk possess no excess capacity and are, at
present, unable to produce an acceptable level of firm capacity (well
field capacity with the largest well out of service for stand-by). An
apparent excess water supply does appear to be present in the northern
Montgomery trunk. This apparent excess capacity could conceivably be
transmitted to the South Valley service area through an existing bypass
line. The apparent capacity of the Montgomery trunk is only superficial
in that peak demand does not exceed the capacity of all available units
operating simultaneously. An integral part of any water system design is
the provision of standby capacity to be employed in the event of system
c~ponent failure. Utilizing a reasonable assumption that the largest
well in a particular well field is dedicated to stand-by (as per the City
Master Plan), no true excess capacity is available in the Montgomery
Trunk. It would not be prudent to jeopardize the balanced water supply
network of the Montgomery trunk in order to counterbalance present fire
protection water supply shortages in the Ridgecrest trunk. This alterna-
tive was, therefore, eliminated.
Following the screening process, two treatment alternatives (activated
carbon and air stripping> and one nontreatment alternative (new well)
remained. These alternatives were developed in more detail which
included a discussion of the following factors:
o Description of each remedial action alternative;
o An assessment of its effectiveness in removing
contaminants found in SJ-6;
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15
o Environmental. safety. and institutional
considerations; and
o Cost (capital and operation/maintenance costs).
After the three remaining alternatives were developed addressing the
above factors. they were each evaluated using the following criteria:
Monetary Evaluation
o Cost - capital. operation/maintenance. salvage values
and present worth costs.
In regard to the operation and maintenance costs calculated for the air-
stripping and new well alternatives. two schemes were utilized. The
first scheme considered that the selected alternative would be operated
on a schedule similar to that of SJ-6 when the well was in service. No
wells in the San Jose field would be utilized preferentially over the
design life of the facility. Operating within this non-preferential
scheme allows cycling of the component wells so that mechanical wear is
evenly distributed among the components. The second operational scheme
considered that the selected alternative would be operated on a preferential
basis and would only be utilized to supply peak demands. Utilization of
this preferential operational scheme transfers the burden of mechanical
wear to the other component wells within the San-Jose field.
Estimated present worth costs for the air-stripping alternative using the
preferential operational scheme could be reduced 24 to 27 percent compared
to using the same alternative. and a non-preferential operational scheme.
Only a 6 to 7 percent present worth cost reduction would be realized if
the preferential operational strategy were utilized for the new well
alternative due to the fact that annual 0 & M costs associated with the
new well alterntive are low relative to the air-stripping alternative.
The cost estimates for the preferential operational scheme do not consider
the reduced service life and associated cost for the other component
wells in the San Jose field which must operate for increased periods.
EPA had requested that their contractor. CH2M Hill. investigate the pre-
ferential operational scheme for air stripping SJ-G. For a limited period.
the selected IRM could be operated on a preferential scheme. At present.
however. it appears likely that the over-all site remedi'ation will be a
lengthy process. Under these circumstances the preferential operational
scheme could not be utilized. The remaining wells in the San Jose well
field would be subjected to unusual wear due to long-term preferential
operation of the air-stripping well. Therefore. for cost comparison
purposes. EPA has evaluated all of the remaining alternatives utilizing
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16
Nonmonetary Evaluation
o Environmental effectiveness - Examples of these criteria
include a positive or negative impact on land use, public
health and environment. public acceptability and safety.
o Engineering feasibility - Examples of this criteria include
technical feasibility and effectiveness, reliability.
operability. ease of implementation and compatibility
with existing facilities. and constructibility.
A detailed discussion of the development and evaluation of the remaining
alternatives can be found in Section 3 of the FFS. Rough cost estimates
(1984 dollars) for the alternatives which appear to be both feasible and
effective are presented in Table 4. Portions of the discussions regarding
the development and evaluation of the alternatives will be explained in
the section entitled IIRecommended Alternative.u
Community Relations
The community relations activities associated with the selected IRM are
included in Attachment 1.
Consistency with other Environmental Laws
A discussion of other environmental laws which could conceivably impact
the remaining three alternatives for this CERCLA initial remedial action
follows:
o Safe Drinking Water Act - All three alternatives are in compliance
with the Safe Dr1nking Water Act. However. no Maximum Contaminant
Levels (MCL) currently exist for the contaminants detected in well SJ-6.
Recommended Maximum Contaminant Levels (RMCL) have been set at zero
for three of the four contaminants detected during the 1984 pump test
of SJ-6. It is not known. at present. whether the zero based RMCLs
will be adopted as MCLs. or if the RMCLs will be modified before being
adopted. For this reason. it is difficult to evaluate the treatment
efficiency of the two treatment alternatives or to ascertain compliance
of the two treatment alternatives with MCLs which may be adopted at
some future date.
o Clean Air Act (CAA) - The new well and carbon adsorption alternatives
will not be 1mpacted by the CAA. Air emmissions of volatile organic
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Table 4 .
MONETARY EVALUATION OF ALTERNATIVES
Annual
Opera t ion a
and b Alternative Present Worth
Capital Maintenance Salvage Value and (Rank)
Alternative Cost Cost 5 yr 10 yr 20 yr 5 yr 10 yr . 20 yr
Air Stripping 499 36 374 250 0 403 (1) 624 (1) 805 (1)
Csrbon Adsorption 1,806 329 1,354 903 0 2,212 (3) 3,479 (3) 4,607 (3)
New We 11 775 12 581 388 0 460 (2) 699 (2) 877 (2)
a
bOased on an interest fate of 10 percent.
Assumes a composite service life of 20 years for all alternatives.
~
-...J
Notes:
All costs are in 1,000's of dollars.
All costs are presented for comparative purposes only.
final project scope, actual labor and msterials costs,
schedule, snd other variable factors.
Actual costs viII vsry depending upon
competitive market conditions,
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18
to treat contaminated SJ-6 waters. Compliance with emission control
standards may be required should the air stripping alternative be the
selected IRM.
Recommended Alternative
Section 300.68 (j) of the National Contingency Plan (NCP) states that the
appropriate extent of remedy shall be determined by the lead agency's
selection of the remedial alternative which the agency determines is cost-
effective (i.e., the lowest cost alternative that is technologically
feasible and reliable and which effectively mitigates and minimizes damage
to and provides adequate protection of public health, welfare, or the
environment). Based upon our evaluation of the Focused Feasibility
Report, EPA has determined and the State has agreed, that the new well
alternative meets the NCP criteria. The following discussion describes
the recommended alternative and the reasons for its selection.
The carbon adsorption treatment alternative was not included in the fol-
lowing discussion because it is about 600 percent more costly than the
air stripping treatment alternative with no measureable advantages. (see
Table 4.) For a complete discussion of this alternative please refer to .
sections titled NDevelopment of Alternatives and Initial Screening and
Evaluation of Alternatives" in FFS.
The recommended alternative consists of constructing a new well to replace
SJ-6. A specific location for the new well cannot be determined at this
time. A site for the new well will be carefully selected using the extent
of contamination assessment developed during the remedial investigation
and site specific hydrogeological data. The new well would be chlorinated
at the wellhead and would discharge directly into the distribution system.
Based on the well siting survey to be performed, the agency expects that
the new well will be productive and would not introduce contaminants
into the Albuquerque water distribution system. This alternative does
not depend on ~ treatment process and, therefore, has a very low risk of
failure.
Environmental impacts of the new well alternative would be essentially
nonexistent. The alternative would be consistent with approximately 80
other existing water supply wells in the Albuquerque water supply system.
In addition, the recommended alternative would be easily implemented since
it is compatible with the existing Albuquerque water supply system and
does not require additional sampling and/or pilot testing to implement.
However, a siting investigation will need to be performed. This will con-
sist of reviewing City files on existing wells, gathering and evaluating
available geohydrology data, and preparing a well-siting report.
Cost information is shown on Table 5. The operation and maintenance cost
(annual costs) of the new well is estimated at $12,000 annually. This
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19
Tabl e S
New Well Construction Costa
Item
Estimated
Cost
Land (100 x 100 ft)
Drilling and Casing
(1,200 ft deep)
Pump Building and Pump
Automatic Controls
Chlorination System
Drain Line (1,600 ft)
Collector Line (300 ft)
Well Siting Investigation
Subtotal
$ 10,OOOb
212,OOOb
200,000b
2S,000b
2S,000b
40,000b
10,000b
20,000
$S42 ,000
Contingency (30~)
Subtotal
163,000
$70S,000
Administrative, Legal, and Engineering
Total
70,000
$775,000
Estimated Annual Cost - New Well
Item
Estimated Cost
Labor
. Materials
Total
$ 8,000
$ 4,000
$12,000
aCosts shown are for a new well at the location shown in the City's Water
Supply Master Plan for Yale Well No.7; i.e., just northwest of Gibson
Boulevard and University Boulevard.
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20
chlorination system at the new well and not at SJ-6. The $12,000 annual
cost does not include the electric power needed to run the new well since
it would be essentially the same as the power costs for running SJ-6 in
the treatment alternatives.
The evaluation of the air stripping alternative is limited to the use of
packed towers. Other stripping methods - namely, stripping ponds or basins,
have been screened from further consideration because of the -larger land
area required, relative cost, and higher risk of contamination.
Based on contaminant concentrations presented in Table 1, two towers, 12
feet in diameter, with a packing depth of approximately 13 feet appear to
be needed. All new components would be located at the existing San Jose
storage reservoir site.
The tower size depends on several factors, such as temperature and ambient
air quality. However, the influent contaminant concentration is the most
important factor. With only two influent data points on the most difficult
contaminant to air strip (1,2-dichloroethane), rationally judging future
influent concentrations is not possible. Therefore, the need exists for
additional sampling and analysis, in order to develop a sound data base
prior to design, if this alternative were to be implemented.
Studies referenced in the FFS have shown that air stripping is an effec-
tive means of lowering the concentration of volatile organic compounds
and should be capable of treating the water from SJ-6 to concentrations
below the levels associated with a 10-6 cancer risk.
Air quality should not be seriously impacted by implementing this alter-
native. For a packed tower installation in which influent volatile
organic concentrations were near 1,000 ug/l, a concentration 15 times
greater than what is found in SJ-6, computer modeling found ground level
concentrations several orders-of-magnitude less than Occupational Safety
and Health Administration (OSHA) and National Institute of Occupational
Safety and Health (NIOSH) standards.
The air stripping alternative could not be as easily implemented as the
new well alternative since it is an unfamiliar technology relative to cur-
rent Albuquerque water supply system operations. Special controls and
warning devices will need to be part of this alternative along with special
training of city personnel.
Noise will be associated with the operation of the air stripping system
which may be objectionable to area residents. Also under certain weather
conditions, water vapor emitted from the stripping towers may form localized
fog or icing conditions which may also be a objectionable to area residents.
Table 6 presents the estimated capital and annual operation and maintenance
costs for this alternative. Influent and effluent dichloroethane concent-
rations were assumed to be 4 and 0.6 ug/L respectively. Table 4 summarizes
the results of the monetary evaluation, and the alternatives are ranked
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21
Tab 1 e 6
ESTIMATED CAPITAL COST-PACKED TOWER AIR STRIPPING
Item
Estimated Costa
Bond, Insurance, Mobilization
Stripping Towers
Piping, Plumbing
Pump and Wet Well
Blowers
Samplers and Meter
Sampling Program
Instrumentation and Control
Pre-desi gn
Subtotal
Contingency (30~)
$ 12,000
180,000
10,000
21,000
17,000
12,000
12,000
40 ,000
30,000
$334,000
Subtotal
100,000
$434,000
Administrative, Legal, Engineering
65,000
$499,000
Total
ESTIMATED ANNUAL COST-PACKED TOWER AIR STRIPPING
Item
Estimated Cost
Labor
Electric Power
Laboratory Testing
Parts, Supplies
$ 5,000
16,000
6 ,000
1,000
$28,000
Contingency (30~)
Total
8,000
$36,000
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22
(1) Air Stripping
(2) New Well
(3) Carbon Adsorption
It should be noted that the present worth costs for the air stripping and
new well alternatives are very similar. The air stripping alternative is
low in capital costs but high in operation and maintenance costs where
the reverse is true for the new well alternative.
Table 7 summarizes the advantages and disadvantages between the air strip-
ping and new well alternatives with regard to nonmonetary considerations.
The advantages of the air stripping alternative are: It is an effective
means of lowering the concentration of volatile organic compounds to the
required concentrations; it does not require the purchase of additional
land; and it does not significantly impact the environment. At one time,
it had been assumed that the air-stripping of well SJ-6 could lead to the
rehabilitation of the contaminated aquifer. Based upon preliminary reme-
dial investigation results associated with the off-site study, it appears'
that the intermediate aquifer overlying SJ-6 is contaminated. The source
of lower aquifer contamination appears to be the intermediate aquifer.
The pumping of SJ-6 may provide a major driving force which would facili-
tate the transfer of contaminated water from the intermediate aquifer
to the lower, water-supply aquifer. Insufficient data are currently
available with which to formulate aquifer remediation strategies. The
data in-hand do suggest that well SJ-6 would not be a suitable location
for a rehabi1ation well designed to reclaim contaminated waters in the
intermediate aquifer. At present, the impact of the air-stripping IRM
upon the long-term rehabilitation of contaminated aquifers in the South
Valley appears to be marginal.
One of the more significant disadvantages of an air-stripper is that this
alternative would be an unfamiliar technology to the City's operational
staff and would have to be integrated into the City's existing water sup-
ply and distribution facilities. Controls would have to be provided to
assist in minimizing operator attention. In addition to the above, inten-
sive sampling and testing likely to be required by the local health depart-
ment make this alternative undesirable with regard to operational consider-
ations. Also of significance would be the fact that air-stripper effluent
quality deteriorates as influent contamination concentrations increase.
Off-site investigations have indicated surface aquifer and intermediate
aquifer contamination. Therefore, the potential for increased contamina-
tion concentrations reaching the lower aquifer and SJ-6 exists. Also a
disadvantage of the air-stripping alternative is that RCRA hazardous waste
treatment standards would be required and associated record-keeping and
reporting requirements would have to be implemented. Compliance with air
pollution emission standards may also be required. These procedures are
all currently unfamiliar to water treatment personnel and an increased
level of effort would be required to insure compliance with applicable
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Tabl
NON-MONETARY COMPARISON OF AIR STRIP~lNG VERSUS NEW WELL ALTERNATIVES
Air Stripping
New Well
Lower present worth cost than a new well.
Advantages
Lower operation and maintenance cost than air stripping.
Lower capital cost than a new well.
Can be located on the San Jose Resevior site to
avoid purchases of additional land.
Less risk of the introduction of contamination into the water
distribution system assuming uncontaminated water at the new
si tee
Not sensitive to qualitative or quantitative variations in
contamination, because it does not require treatment.
More acceptable to the general public and water system opera-
ting staff.
Compatible with the existing water supply system.
Disadvantages
Higher operation and maintenance cost than a new well.
Is sensitive to qualitiative and quantitative vari-
ations in contamination.
Higher present worth cost than air stripping.
Higher capital cost than air stripping.
N
W
Would require additional sampling.
Would require water system operating personnel to
become familiar with and operate a process with
which they have no prior experience.
No guarantee that the new well will not become contaminated
in the future.
No assurance that the new well will be as productive and" effi-
cien as SJ-6 was historically.
Would require the purchase of additional land.
Would require ongoing sampling and testing to
monitor treatment efficiency.
Could result in seasonal fogging/misting problems
in vicinity of air stripping towers.
Could result in minor nuisance to residents in the
immediate vicinity of the site because of added noise.
Would require c9mpliance with RCRA and, possibly, CAA.
Associated record-keeping and reporting procedures
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24
Other disadvantages of the air stripper alternative include localized minor
environmental impacts immediately adjacent to the site. The site where
the air stripper would be located is in a residential area, and it is anti-
cipated that noise from blowers and occasionally mist, fog and/or ice from
the stripping towers could cause a minor nuisance to residents in the the
immediate vicinity of the site.
" -
The are several advantages to the new well alternative. It easily integrates
into the City's current water supply and distribution facilities. Operators
are accustomed to this type of system, and it involves much less operator
attention than would air stripping. This is important since with a new well,
water quality is not nearly as dependent on the precise operation of the
facility, as with an air stripping system. These advantages are very signi-
ficant, since the City of Albuquerque would own and operate whatever system is
installed and would not be required to train operators or alter their normal
mode of operation, in order to insure required water quality. With a new
well, the possible variance of influent contamination levels is not an issue
since a well siting survey will be performed to insure that it is located
in an uncontaminated aquifer zone. Other than chlorination facilities,
operational controls are not necessary to produce the required water quality.
Additionally, a new well does not require the application of RCRA generator,
treatment, storage, or disposal standards, or other extraordinary regulatory
standards, and the attendant resources and costs associated with such reg-"
ulation. With a proper well siting survey, there should be no potential
negative impacts on the deeper drinking water aquifer. A new well provides
a soundly engineered, environmentally safe and reliable water source to
meet peak fire-protection demand needs.
Disadvantages of the new well alternative include the possiblity that it
might not be as productive and efficient as SJ-6. Additonally, it would
require the purchase of land. A new well is more costly than an air
stripper on SJ-6, mainly due to its higher capital cost.
Reconunendation
Although the packed tower air stripper alternative appears to be less
costly in terms of capital outlay and marginally less costly in terms of
present worth over a twenty year life, this alternative is not deemed
to be as environmentally sound as the new well alternative. The unfamiliar
technology of the equipment to the Albuquerque water system is considered
to be of major significance as an indicator of reliability. Personnel
must be specially trained and maintained to operate this system, and the
system would require ongoing sampling and testing of water quality to
constantly ensure and monitor treatment efficiency. As indicated
previously, air stripper effluent (treated water) quality deteriorates
significantly as influent or intake contamination levels increase. If
levels of contaminants were to increase, costs can rise sharply and
treatment efficiency is reduced. Water quality and with it public health,
would be dependent on the successful 0r.eration of this "add-on" system.
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and a well siting survey would help to insure that it is located in an
uncontaminated zone of the aquifer. It has been noted that the new well
alternative does nothing to purge or treat the aquifer, yet it cannot be
said with any degree of certainty that an air stripper placed on SJ-6 would
be useful for such a purpose either. Simply not enough is yet known
about the geohydrology of the aquifer at this time to determine a remedial
remedy. On the other hand, there are preliminary indications that air
stripping operation of SJ-6 may produce a driving force that would facilitate
the transfer of contaminants to the deeper aquifer. This should not be
the case with a new well following a well siting survey. A new well
provides an environmental margin of safety that overcomes any cost advantage
of an air stripper. It is more environmentally sound and protective of
public health. This is very important, since the hazardous substances
now contaminating the SJ-6 drinking water supply are an endangerment to
public health and environment. Further, possible costs of RCRA regulatory
compliance and of compliance with other environmental statutes, could
add substantial costs to the air stripper alternative that are presently
unquantified.
Based on the above evaluation of alternatives and the administrative
record for this proposed initial remedial measure, it was determined
that initial remedial measures are necessary and feasible to limit
exposure or threat of exposure to a significant health or environmental
hazard. It was further determined that the new well alternative is the
most cost-effective, environmentally sound initial remedial measure to
address such exposure, or threat of exposure. It is therefore the recom-
mended alternative. This measure is consistent with any permanent remedy
to prevent or mitigate the migration of a release of hazardous substances
into the environment. The capital cost of this alternative is $775,000,
with annual operation and maintenance costs estimated at $12,000 (1984
dollars).
Operation and Maintenance
The operation and maintenance cost of the new well is estimated at $12,000
annually. Of this $8,000 is for labor and $4,000 is for materials. This
cost is primarily associated with the operation and maintenance of the
chlorination system at the new well and not currently at SJ-6. The $12,000
does not include the electric power needed to run the new well since it
would be essentially the same as the power cost for running SJ-6 in the
treatment alternatives.
The City of Albuquerque has agreed to accept all operation and maintenance
costs for the operating life of the well.
Schedule
- Approve remedial action (sign ROD)
- Complete enforcement negotiations
March 1985
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- HQ tasks the Corps. of Engineers to
begin design
- Start design (includes well siting
survey)
March 1985
- Complete design
May 1985
February 1986
- Start construction
May 1986
November 1986
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Community Relations Responsiveness Summary
Initial Remedial Measure
Albuquerque South Valley
Introduction
The purpose of this responsiveness summary is to document for the public
record concerns raised by the public in regard to the proposed initial
remedial action of installing a new water supply well at the South Val-
ley Superfund site in Albuquerque, N.M. EPA consideration of or response
to concerns raised will also be documented in this section.
In addition to the proposed IRM action, contamination source control
and offsite aquifer rec1aimation actions may be required at some future
date pending completion of associated Remedial Investigations and
Feasibility Studies. This responsiveness summary addresses only those
concerns associated with the initial remedial measure (IRM) comprising
the installation of a new well in the Albuquerque South Valley.
Concerns and Responses
On August 21 and 22, 1984, public meetings were conducted in Albuquer-
que on the proposed IRM. Additional comments were received and follow-up
meetings were held through January of 1985. Significant concerns and
EPA responses to those concerns follow.
1. Several comments were received which questioned whether there was
an immediate need for the water supply capacity lost due to the
contamination of SJ-6. Further concern was expressed that proper
documentation was not provided pertaining to the Governor of New
Mexico's request for the IRM (40 CFR Part 300.67[b]) nor was it
demonstrated that the prerequistites for an IRM (40 CFR 300.68[e])
were met.
The fact that SJ-6 had been taken out of service due to contamina-
tion problems has had a serious impact upon the available fire-pro-
tection water supply in the South Valley service area. Fire-protec-
tion equipment purchases and fire-protection strategy development
have been based upon the availability of three million gallons of
reserve storage capacity to be maintained in .system storage tanks.
Serious fire-protection water supply shortages occurred during the
summer of 1980 when system water demand exceeded well supply for
sustained periods and storage volume dedicated to fire-protection
was utilized to satisfy daily demands. Fortunately, no major fire
occurred during these conditions. Similarly severe water shortages
did not occur during the period 1981 through 1984 due, almost
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2
received during the summer months relative to 1980. Statistics
developed by the Middle Rio Grande Council of Governments of New
Mexico indicate that population increases were projected for the
South Valley area during this same period of time. A year of
similar dryness to that of 1980 would be relatively likely and the
magnitude of fire-protection water supply shortfalls are antici-
pated to be more severe than the shortfalls experienced i~ 1980
due to industrial and population growth.
As required by 40 CFR Part 300.67(b), the Director of the New Mexico
Environmental Improvement Division has requested EPA assistance in
implementing the IRM at the South Valley Superfund site. The pro-
posed initial remedial action is being conducted in conformance
with the NCP Parts 300.68 as published in the Federal Register on
July 16, 1982, 40CFR 300.68. Sufficient fire-protection water supply
has not been available on a reliable basis in the South Valley ser-
vice area since well SJ-6 was taken out of service due to contami-
nation by hazardous substances. Parts 300.65(a) and (b) of the NCP,
which are relevant to IRM's although addressed to removal action,
state that immediate action such as providing alternate water sup-
plies shall be deemed appropriate in acute situations which pose a
significant risk to human life or health or to the environment.
Part 300.68 (e)(l)(vi) of the NCP states that an IRM is appropriate
if there exists a serious threat of fire or explosion or other seri-
ous threat to public health or the environment. The lack of suffic-
ient fire-protection water supply due to the contamination and
subsequent shut down of SJ-6 satisfy the conditions for immediat~
action set forth in Parts 300.68 of the NCP. Well SJ-6 could
conceivably be pressed into service to supplement the fireprotection
water supply during peak demand periods. However, based upon the
concentration of contaminants identified in well SJ-6 and proportion-
ing the flow capacity of SJ-6 to the total San Jose well field
capacity, it was determined that water delivered to the tap would
pose a threat to public health if consumed. Contaminated drinking
water at the tap satisfies the conditions for conducting an IRM as
set forth in Part 300.68 (e)(l)(iii) of the NCP.
2. Several comments were submitted which asserted that the objective
of the FFS should have been to alleviate the fire-protection water
supply shortfall resulting from the shut-down of contaminated well
SJ-6 until the future of the San Jose well field was known. As
originally stated, the purpose of the FFS was to evaluate remedial
action alternatives for putting SJ-6 back into service or replace
the capacity of SJ-6.
The purpose of the proposed IRM is to mitigate any immediate
endangerment to the public welfare which resulted from the shutdown
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3
performed with the stated objective of putting SJ-6 back into
service or replacing the capacity of SJ-6. This objective was set
based upon the City of Albuquerque's current need for the total
capacity of SJ-6 to provide adequate fire-protection water supply
and system reliability. Documentation of this need was provided in
a City report included as Appendix A of the FFS. An amendment to
the FFS was commissioned to consider additional alternatives which
would mitigate the City's fire/peak demand shortfall. Further
documentation of the City's immediate need for the water supply
capacity formerly supplied by SJ-6 was provided in the FFS Amendment.
The FFS Amendment also considered other alternatives such as construc-
tion of additional storage capacity and transfers of excess capacity
to the South Valley service area from elsewhere within the Albuquerque
water system. These alternatives were eliminated from further consi-
deration. however. due to excessive costs or infeasibility. Thus,
the objective of the FFS, to determine a cost effective method for
supplying a potable source of water equal in quantity to that previ-
ously supplied by SJ-6. is the only cost-effective approach to
alleviating the fire-protection water supply shortfall which exists
in the South Valley service area.
3. One comment received strongly argued that results of water samples
analyzed from well SJ-6 during the period 1980 to 1982 were not
consistent with results of water samples analyzed during the two
week pump test of SJ-6 which occurred in April and May of 1984.
Further, concern was expressed that adequate QA/QC procedures were
not employed for samples analyzed during the period 1980 to 1982
and that a critical contaminant, 1,2-dichloroethane, was never
present at concentrations of concern in SJ-6 water samples analyzed.
For contaminants identified at concentrations exceeding 5 ug/l, ex-
cellent agreement was noted between samples analyzed from 1980 to
1982 and those samples analyzed in 1984. Mean values, ranges, and
relative number of times the contaminant was found to occur were
comparable for the two sampling periods for 1,1-dich10roethane.
1,1-dich10rethene, trich10roethene and tetrach10roethene. Several
volatile organic constituents (dich10romethane, trichloromethane,
tetrach10romethane, l,2-dichloroethane, 1,1,l-trich10roethane and
l,2-transdichloroethene) were detected at concentrations less than
5 ug/l during the sample analyses performed over the 1980 to 1982
period. Each of these contaminants was detected at quantifiable
concentrations on only one or two occasions. In contrast, none of
these contaminants were detected in the 1984 samples which were
analyzed. Although the rigorous QC procedures required for present
day analyses were not fully employed for samples analyzed from SJ-6
during the 1980 to 1982 period, there are several reasons to suspect
that l,2-dich10roethane, in particular, was indeed present. First,
a review of the New Mexico Environmental Improvement Division (NMEID)
laboratory results of February 25, 1982, indicated that 4 ug/l of
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4
GC/MS while no 1,2-dichloroethane was detected in the laboratory
blank. In addition to the sample and blank, a low level standard
of 10 ug/L 1,2-dichloroethane was also analyzed by the M~EID labora-
tory. This laboratory has been audited yearly by the EPA since
about 1978 and has always performed well. Secondly, another inde-
pendent laboratory, Anachem, Inc., analyzed a sample collected from
well SJ-6 on the same day as the NMEID sample. Again, 1,~-dichloro-
ethane was found to be present in the sample, albeit, at a lower
concentration.
The compound l,2-dichloroethane is a carcinogen with a Recommended
Maximum Contaminant Level for drinking water of zero. In performing
a prudent assessment of the data available, EPA considers that the
1980 through 1982 analytical results are consistent with the 1984
results. Further, EPA has agreed with the conclusions of its con-
tractor, CH2M Hill, that 1,2-dichloroethane is a contaminant of
well SJ-6 and may be present at concentrations up to 4 ug/L.
4. Several comments were received which questioned the use of Recommended
Maximum Contaminant Levels to assess the impact of well SJ-6 contami-
nation upon human health.
Recommended Maximum Contaminant Levels (RMCLs) are defined, in the
Federal Register date June 12, 1984 on page 24352, as "the maximum
level of a contaminant in drinking water at which no known or
anticipated adverse effect on the health of person would occur and
which includes an adequate margin of safety". Therefore, RMCLs are
related to health levels. Although RMCLs are not enforceable
standards, they do serve as goals for the Agency in the course of
setting Maximum Concentration Limits (MCLs) which are enforceable
standards. RMCLs are, therefore, initial steps in the MCL rule making
that will follow. In some cases MCLs will be very similar to the
RMCLs; in other cases control processes and economic considerations
may dictate an MCL that is not similar to the RMCL.
In regards to the South Valley site, there are no published MCL
standards for the four contaminants which were detected during the
April and May 1984 sampling effort. In accordance with above
mentioned Federal Register, there are RMCLs for three of the four
contaminants detected during April and May 1984. The RMCLs for the
following three compounds are zero:
(1) 1,1-dichloroethylene
(2) trichloroethylene
(3) tetrachloroethylene
The goal of most CERCLA remedial actions where suspected carcinogens
have been detected is to reduce the concentrations of potential
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5
11 fetime cancer risk is typica'j ly used. Concentrati ons of three of
the four primary compounds detected during the April/May sampling
effort exceed the 10-6 excess cancer risk level even if well-
field dilution is considered.
Therefore, a threat to public health would be associated with human
consumption of untreated water produced from well SJ-6. .
5.
Several commentors urged that any remedial action taken to restore
capacity lost by the contamination of SJ-6 be postponed until the
overall site clean-up 'strategy was developed. The point was made
that the City of Albuquerque has been able to operate the water
system effectively and avert any water supply shortages since the
time SJ-6 was taken out of service.
The fact that SJ-6 had been taken out of service due to contamina-
tion problems has had a serious impact upon the available fire-pro-
tection water supply in the South Valley service area. The most
serious recent fire-protection water supply shortages occurred dur-
ing the summer of 1980 when water dedicated to fire-protection was
utilized over a sustained period to satisfy daily demands even with
SJ-6 still in service. Fortunately, no major fires occurred during
these conditions. Similarly severe fire-pr9tection water shortages
did not occur during the period 1981 through 1984, although shortages
did occur. Statistics prepared by the Middle Rio Grande Council of
Governments of New Mexico indicate that population increases have
occurred in the South Valley area over the period 1980 to 1984.
Relative to the summer of 1980, higher amounts of rainfall were
recorded during the summer months of 1981 through 1984. A year of
similar aridity to that of 1980 would be likely in the Albuquerque
area, and the magnitude of fire-protection water supply shortfalls
are anticipated to be more severe that the shortfalls experienced in
1980. It is also anticipated that the over-all remedial strategy
for the South Valley site will not be fully developed until 1987.
This would most likely result in the City having insufficient
fire-protection water supply for, at least, the next three years.
Due to the immediate endangerment to the public welfare posed by
insufficient fire-protection water supply in the South Valley ser-
vice area, the IRM should be implemented at this time. The NCP
regulations at 40 CFR 300.68 are clear that IRMs are authorized in
such circumstances.
6. A number of comments were critical of the orginial FFS in that
alternatives such as construction of additional storage facilities
and/or the transfer of excess capacity from other regions of the
Albuquerque water system to the South Valley service area were not
considered.
The FFS Amendment considered such alternatives as inter- and intra-
system transfers as well as the construction of additional storage
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6
Allowing for a stand-by capacity of one well per well field, no
excess capacity was found to exist in the northerly Montgomery
trunk. Other trunks do not possess adequate stand-by capacity and
in some cases, do not have sufficient capacity to meet peak demands
even with all wells in service. Likewise, the upper zones of the
Ridgecrest trunk do not have sufficient well supply capacity to
meet peak demands. The cost of constructing additonal storage
capacity sufficient to offset production shortfalls experienced in
1980 (which was not an exceptionally dry year) would exceed the
cost of the selected a~ternative by a factor of three.
7. One comment asserted that in developing cost estimates, a cost
credit should have been considered for the air stripping alternative
in that the long-term remedial measure would be less expensive due
to the fact that an air-stripping IRM would lead to the reclamation
of t~e contaminated aquifer. Further, the use of a twenty year
design life was challenged. The writer also considered it inappropriate
to include analytical monitoring costs of SJ-6 since these costs
would be a component of the long-term remedial measure.
The NCP (40 CFR Part 300) requires that a cost effective evaluation
rather than a cost/benefit analysis be performed upon the alternatives
considered. At the present time, it might be very difficult to
determine what level of cost savings, if any, would be realized for
the long-term remedial measure by implementing the SJ-6 air-stripping
IRM. Even with the results of the initial phase of the off-site
investigation in-hand, it is not yet possible to speculate upon what
the long-term clean-up strategy will be for the South Valley site
especially with regard to the potential recommission of well SJ-6.
Pumping and treating of the deep aquifer mayor may not be a compon-
ent of the long-term remedial measure. Should the pump and treat'
alternative be included as part of the over-all clean-up strategy,
more than one treatment station may be required to accomplish the
reclamation of the deep aquifer. Whether SJ-6 would be selected
as one these treatment stations and just what portion of the aquifer
clean-up would occur at SJ-6 can not be determined at present.
Present indications are that the bulk of any aquifer rehabilitation
program would occur in the intermediate aquifer. Due to the uncert-
ainties previously discussed, the FFS considered cost comparisons
for 5, 10 and 20 year design lifes when evaluating the cost-effec-
tiveness of the new well and air-stripping alternatives. In regard
to the inclusion of monitoring costs as a component of the air-strip-
ping IRM, it must be restated that pumping and treating of the deep'
aquifer mayor may not be a component of the long-term remedial
measure. In additon, any deep aquifer waters withdrawn and treated
as a component of any long term remedial measure mayor may not be
utilized directly as a potable source. Therefore, in a prudent
evaluation of the new well alternative (where no unusual level of
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7
alternative (where additional sampling efforts would be required in
order to monitor the quality of treated water from a contaminated
source), it was necessary to include the costs of this increased
analytical effort for the air-stripping initial remedial alternative.
8. A comment was received which stated that capital cost estimates
developed for the air-stripping alternative were excessive. The
commenter had requested that U.S. EPA, Office of Water, Technical
Support Division generate a cost estimate for the air-stripping
alternative considered. as a South Valley IRM. Upon receipt of the
Office of Water cost estimate, the commentor submitted these findings
to U.S. EPA Region VI Superfund Branch.
Utilizing a model developed by the.US EPA, Office of Water, Technical
Support Division and similar input data to that used by EPAs
contractor in the development of the FFS, a present worth value of
$579,000 was calculated for air-stripping of well SJ-6. This figure
is thirty-percent lower than the present worth cost presented in
the FFS. Several key differences should be noted when comparing
the two estimates, however. First, EPA's contractor developed the
present worth cost estimate presented in the FFS based upon bid-
tabulation data derived from installations of similar air-stripping
units. The Office of Water model, on the other hand, was developed
primarily to specify design criteria and, secondarily, to estimate
cost. The cost estimating function had not been updated for several
years. Second, the treatability rate constant utilized in the
Office of Water model is based upon a Henry's Law constant for the
removal of 1,2-dichloroethane and not a value derived from field
investigations. A conservative designer would be justified in
utilizing a reasonable factor of safety based upon the lack of suit-
able field verification for the air-stripping of 1,2-dichloroethane.
This justifiable conservatism resulted in the air-stripping system
described in the FFS being larger and requiring operation at higher
air to water ratios than the design specified by the Office of
Water. This difference in design philosophy is also reflected in
the higher cost of the air-stripping system described in the FFS.
The air-stripping cost estimates presented in the FFS appear to be
based upon sound engineering judgement and are believed to adequately
reflect those costs which would be incurred to satisfy FFS objectives.
9. Several comments questioned the validity of the subjective concerns
cited as disadvantages to the air-stripping alternative presented
in the FFS.
CH2M Hill, the EPA contractor responsible for performing the South
Valley Focused Feasibility Study, has had considerable experience
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8
pounds. As a component of the FFS report, the following subje,tive
concerns were considered as disadvantages to the air-stripping
al ternative:
1. Sensitivity to quantitative and qualitative variations in
contaminants. -
2.
Requirement for water system operating personnel to become
familiar with and operate a process with which they have had no
prior experience. .
3. Requirement for ongoing sampling and testing to monitor treatment
effi ci ency.
-
4. Potential for seasonal fogging, misting or icing problems in
the vicinity of the stripping towers.
5. Potential for a minor nuisance to residents in the immediate
vicinity of the air-stripper due to added noise.
The treatability of air-stripped contaminants is a function of Henry's
Law and mass transfer coefficients. Field verification of these'
assertions for various contaminants has been performed by numerous
researchers. It is a fact that influent contaminant concentrations
and/or flow rate will significantly influence the treatability and
subsequent effluent concentrations of the strippable, volatile
organic contaminants. Off-site investigations have indicated
surface aquifer and intermediate aquifer contamination in the
vicinity of well SJ-6. Therefore, the potential for increased
contaminant concentrations reaching SJ-6 exists. It is also a fact
that an air-stripper would be an unfamiliar technology to the
City's operational staff. Staff training would need to be conducted.
The system would also need to be integrated into the existing water
supply and distribution facilities. Controls would be required in
order to minimize operational attention while monitoring the vital
operating parameters of the air-stripping facility.
The air stripping alternative will also require more sampling simply
because it is a treatment process which depends upon certain operating
parameters. If the air stripper is not operating properly, immediate
adjustments may be required in order to insure that water discharged
from the treatment system is of sufficient quality for human
consumption.
Under suitable conditions, and in the vicinity of the air-stripper
fogging, misting or icing problems could occur as a result of air-
stripping operations. Likewise, dependent upon the selected location
of the air-stripper, localized noise problems may result which
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9
Implementation of the air-stripping alternative would require comp1iance
with RCRA and, possibly, CAA. Associated record-keeping and reporting
procedures would need to be implemented by the City.
10. One comment received suggested that the inclusion of a chlorination
facility with the new well alternative should not be considered due
to the fact that this action would constitute a betterment of the
existing facility.
Water produced by SJ-6 is presently chlorinated at the San Jose
reservior. It is quite likely that the location of the new well
will not permit economical discharge to an existing chlorination
facility of appropriate capacity. To satisfy the IRM objective of
providing sufficient fire-protection water supply lost by the
contamination of SJ-6, it was determined that the full capacity of
SJ-6 must be restored. Therefore, should an existing chlorination
facility of appropriate capacity not be available in the vicinity
of the new well, provision of such chlorination facilities would
not constitute a betterment in that the project objective is to
replace capacity, not replace equipment.
11. Several comments were received which noted risks involved with
implementation of the new well alternative in regard to producing
water of equivalent quality and quantity to that of SJ-6.
Prior to installation of the new well IRM, a well-siting survey
will be conducted and the re~ults of the off-site investigation
especially with regard to deep aquifer sampling and analysis will
be reviewed. These measures are intended to provide the necessary
background information which would lead to the selection of a well
site with yield equivalent to that of SJ-6 and a water quality
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