20040319Prescott Rebuttal.pdf

'-'\~_
Ct.! ,/
;',
- !LEO
"'i",,"rJ I."Ht
/li\J'1 ii-ii\ ..I II t..j. VI
. ,- '
: i"
JTIL't'liES COnr'i!SSION
BEFORE THE IDAHO PUBLIC UTILITIES COMMISSION
IN THE MATTER OF THE APPLICATION
OF IDAHO POWER COMPANY FOR
AUTHORITY TO INCREASE ITS INTERIM
AND BASE RATES AND CHARGES FOR
ELECTRIC SERVICE.
CASE NO. IPC-O3-
IDAHO POWER COMPANY
DIRECT REBUTTAL TESTIMONY
JOHN P. PRESCOTT
Please state your name and business address.
My name is John P. Prescott and my business
address is 1221 West Idaho Street, Boise, Idaho 83702.
What is your position at Idaho Power Company?
I am the Vice President of Power Supply.
What is your educational background?
I graduated from Idaho State University in
pocatello, Idaho in 1981 receiving a BS Degree in General
Engineering.In 1987 , I received an MS Degree in Electrical
Engineering from the Uni versi ty of Idaho in Moscow Idaho.
have done postgraduate work towards a PhD in Mechanical
Engineering and Energy Studies at the University of Wales in
Cardiff, UK.I successfully completed the Advanced
Management Program at the Harvard Business School in 2003.
I am currently licensed as a Registered Professional
Engineer in the states of Idaho, Wyoming, California,
Nevada, Oregon, Washington, Montana and Utah.
Please outline your professional experience.
I began my career at the Company in 1982 as a
communications engineer. I advanced through several
engineering and management positions in the areas of power
system operations and substation management.I directed the
Company s R&D program focusing on alternative energy systems
from 1991 to 1994.In 1995 I became the President of
Stellar Dynamics, a wholly owned subsidiary of the Company
PRESCOTT, Di - Reb
Idaho Power Company
doing power control system engineering.I returned to the
Company in 1999 when I was selected to be the Vice President
of Generation.As my responsibilities expanded, I was named
the Vice President of Power Supply in 2001.
What are your duties as the Vice President of
Power Supply?
In this role I am responsible for the safe,
reliable and cost effective supply of electrici ty to the
customers of the Company. This involves the operation and
maintenance of 17 hydroelectric proj ects, the Danskin
peaking plant and the Bennett Mountain peaking plant, which
is currently under construction.I also manage the
Company s interest in three coal fired generation plants in
Wyoming, Nevada and Oregon.I direct the Company s efforts
in resource planning, load forecasting, fuel management,
water management, transmission adequacy, power market
transactions, resource optimization and hydro plant
relicensing and compliance.
What topics will your testimony cover?
I will address the proposal that the
Industrial Customers of Idaho Power make through the
testimony of Dr. Reading that the Company should have
canceled the Danskin Power Plant in 2001 and his
recommendation that the Commission now remove the Danskin
Power plant from rate base.I will also provide additional
PRESCOTT, Di-Reb
Idaho Power Company
information regarding Idaho Power s cloud seeding program
and correct erroneous information the Commission Staff
apparently relied on to support its recommendation that the
Commission (1) exclude the Company s investment in Woodhead
Park from rate base and (2) exclude investment the Company
incurred in defense of its Federal Energy Regulatory
Commission ("FERC") Hells Canyon license relating to the
Biological Opinion.
DANSKIN
Please generally describe the Danskin Power
Plant.
The Danskin Power Plant consists of two
identical 45 MW Siemens-Westinghouse W251B12A natural gas-
fired combustion turbines and the associated swi tchyard.
The 12-acre facility, constructed during the summer of 2001,
is located northwest of Mountain Home, Idaho.In generally
accepted industry parlance, the Danskin Plant is referred to
as a peaking facility.As such, the Danskin plant is
primarily used to meet extreme load conditions, which for
Idaho Power Company usually occur during the later afternoon
or evening hours in mid summer.
Idaho Power identified the near-term need for
peaking facilities in its 2000 Integrated Resource Plan
( "
IRP"
) .
In the 2000 IRP Idaho Power announced that the
Company would issue a Request For Proposals for a peaking
PRESCOTT, Di - Reb
Idaho Power Company
facili ty as a part of its 2000 IRP Near-Term Action Plan.
In July of 2001 in Order No. 28773, in Case No. IPC-01-12,
the Commission issued a Certificate of Public Convenience
and Necessity to Idaho Power for the Danskin Power Plant.
What is a peaking facility?
The generally accepted attributes of a
peaking facility include relatively low capital (fixed)
costs and relatively high dispatch (variable) costs.It is
also generally assumed in the industry that a peaking
facili ty will operate at a relatively low capacity factor.
Figure 1 depicts a typical load duration curve.
peaking facility operates in the extreme upper left hand
portion of the curve.As indicated in Figure 1, a peaking
facili ty is needed to meet demand for only a few hours in a
year.Figure 1. Typical Load Duration Curve
.....
Intermediate & Base Load Plants
.....
Peaker
........
Hours in Year 8760
PRESCOTT, Di-Reb
Idaho Power Company
What is meant by the term capacity factor?
For a power plant, the capacity factor is the
ratio of the plant's actual generation to the generation
that the plant could have produced if it had operated at its
rated capacity for the number of hours in the period under
consideration.
Are there any guidelines or general rules of
thumb as to capacity factors typically associated with a
peaking plant?
Yes, the Electric Power Research Institute'
EPRI") Technical Assessment Guide Volume 1: Electricity
Supply - 1993 provides this type of information.The
Technical Assessment Guide indicates that the capacity
factor for a peaking plant ranges between 1% and 20%, with a
nominal value of 10%.The Technical Assessment Guide
explains that although the nominal value represents a
lifetime levelized value, actual capacity factors for
peaking plants may vary widely depending on a variety of
condi tions .
What was Danskin's capacity factor in 2002
and 2003?
Based on a capaci ty of 90 MW, Danskin ' s
capacity factor in 2002 was 5.7% and in 2003 its capacity
factor was 5.5%.
Why is Idaho Power bui lding peaking
PRESCOTT, Di - Reb
Idaho Power Company
facili ties?
Historically Idaho Power relied on its hydro
plants to supply peaking needs.As peak loads grew the
hydro system was no longer able to meet all of those needs.
By 2000 it became apparent that the population
growth in the Idaho Power Company service territory and the
fact that most new residences and commercial building were
being equipped wi th air condi tioning were leading to
increased energy consumption during the hot days of summer.
The increase in air conditioning load, combined with
Southern Idaho s strong irrigation load led to a pronounced
summer peak, and these conditions continue today.
Addi tionally, the interstate transmission system that Idaho
Power had historically used to import power in times of
cri tical need was being used to capacity.I t became
apparent that Idaho Power would need to construct additional
generation facilities within the Idaho Power control area
and near its load if Idaho Power was going to continue to
meet its growing summer load.Idaho Power Company
reiterated the need for peaking resources in the 2002
Integrated Resource Plan, and issued a Request for Proposals
for additional peaking resources in February 2003.
Presently, TR2 (formerly Mountain View Power) is
constructing a 162 MW peaking facility for Idaho Power
Company, also in Mountain Home, known as the Bennett
PRESCOTT, Di - Reb
Idaho Power Company
Mountain Power Plant.Preliminary analysis suggests that
addi tional peaking resources may well be one component of
the 2004 Integrated Resource Plan that will be filed in the
summer of 2004.
Has the Company kept the Commission and the
public advised of its need to construct peaking generation
facilities?
Yes.The Idaho Commission accepted both the
2000 and 2002 Integrated Resource Plans in which Idaho Power
Company identified simple-cycle natural gas-fired combustion
turbines as the most cost-effective generation to meet the
summer peak.The Commission has also granted Idaho Power
Certificates of Public Convenience and Necessity for both
the Danskin Plant as well as the Bennett Mountain Plant that
is currently under construction.Both the IRPs and the
Certificate cases were public processes with significant
opportuni ty for public comment.
Please describe the summer peak condi tions
that the Danskin Power Plant is designed to address.
Idaho Power Company experienced its all-time
system peak of 2963 MW during record heat in July 2002.
July 2003, the system peak was 2944.The summer peak may
well exceed 3000 MW this summer.The summer peaks are very
short in duration.In 2003 there were only seven hours
where the system load was 2900 MW or greater.In 2002 there
PRESCOTT, Di-Reb
Idaho Power Company
were only nine hours where the load was 2900 MW or greater.
The winter peaks are far different.During the 2002
- 2003 winter, the maximum system load never even reached
2000 MW.During this past winter, the maximum system peak
was just under 2200 MW.
What is the daily duration of the summer
system peak?
The daily peaks are often quite short.For
example, on the peak day last summer, there were three hours
where the load exceeded 2900 MW and eight hours where the
load was 2800 MW or greater.The minimum load on that day
was just under 1900 MW.
The peak load on that day was over 2900 MW
and the minimum load was under 1900 MW.Are you saying that
there is a difference of over 1000 MW between the daily peak
and the daily minimum?
Yes.In fact, the difference was nearly 1100
MW.The peak of 2944 MW was 1.55 times the minimum load of
1894 MW.The Idaho Power load varies considerably over the
course of a summer day.
How does Idaho Power operate Danskin during
the summer peak condi tions?
It is important to understand that Danskin is
Idaho Power's resource of last resort.Idaho Power only
operates Danskin when it can be economically dispatched into
PRESCOTT, Di-Reb
Idaho Power Company
the market, or when operation is deemed necessary to support
system reliability, or when there are no other options to
serve load.Typically, Idaho Power Company first meets load
wi th its own low-cost resources including the hydro system
and its partial ownership in three coal-fired plants.
Second, Idaho Power will use the transmission system and
purchase additional energy from the wholesale markets.
Third, Idaho Power uses its load-control programs such
the pilot AC program and the pilot irrigation program.
Fourth, Idaho Power uses its natural gas-fired peaking
resources including Danskin and in 2005, Bennett Mountain to
meet load.In this phase Idaho Power may also work with
large industrial and other customers to see if cost-
effective curtailments can be arranged.Finally, if all of
this fails, Idaho Power may be required to pursue the load-
curtailment program on file with the Commission to
involuntarily shut off customers to stabilize the system.
The Danskin Power Plant only operates when all of the other
resources, generation, transmission, and in the future,
expanded load-control programs, are operating at capacity.
In both the 2000 and 2002 IRP's, Idaho Power Company
identified simple-cycle natural gas-fired combustion
turbines as the most cost-effective generation to meet the
summer peak.Even though the fuel cost can be high, the
fact that the turbines are only operated during a few hours
PRESCOTT, Di-Reb
Idaho Power Company
of the year and the fact that the capital costs are
relatively low, and the fact that Idaho Power uses the
facilities during the times of critical summer peak or
winter peaks, for reliability or those times when it can be
economically dispatched into the market, makes plants such
as the Danskin Plant a very prudent choice.
You said that Danskin was the "resource of
last resort", what does that mean?
The resource of last resort means that Idaho
Power Company operates Danskin when there is no transmission
available or when market prices are so high that market
purchases are una tracti ve The Company s transmission
constraints are real.Power may be available at the mid-
Columbia market, but Idaho Power Company may have no way to
get the power into our system.In the summer the
transmission lines from the Northwest, Montana and Nevada
are often operating at full capacity and there is no more
space available for imports into the Idaho Power Control
Area to serve peak loads.The Company may, at times, be
able to import additional power from the eastern side of its
system.However, from a planning perspective, the Company
does not like to rely on purchases from the east for several
reasons.The first concern is the actual availability of
supply on the east.There is not much of a market on the
eastern side of Idaho Power s system.Second, if power is
PRESCOTT, Di - Reb
Idaho Power Company
available on the eastern side of the system, it is typically
higher in price than northwest markets.The third reason
that Idaho Power does not like to rely on purchasing from
the eastern side of the system is because of PacifiCorp ' s
two-thirds ownership in the Jim Bridger Plant.If a Jim
Bridger unit trips, PacifiCorp will be looking to replace
twice as much supply as Idaho Power will, potentially
leading to shortages on the eastern side of the system.
Could Idaho Power improve the transmission
system?
Transmission improvements are possible,
although transmission construction can be very costly and
rights-of-way difficult and time consuming to obtain.
spi te of these problems, Idaho Power is currently pursuing
certain transmission upgrades that could provide some
additional import capability in the next several years.
Can Idaho Power Company meet the summer peak
load with load-control programs?
The load control programs certainly look
promising, but the programs are only part of the solution.
During summer peak conditions, a properly sized residential
AC unit may be on constantly during the peak hours.The
residential AC program cycles residential air conditioners
so that the compressors are on half the time and off half of
the time - the program lowers the AC peak demand of the
PRESCOTT, Di-Reb
Idaho Power Company
house by half.In ballpark figures, if Idaho Power Company
adds 10,000 new residential per year, Idaho Power Company
would have to enroll 20,000 residential customers in the AC
load control program to offset the AC load from the 10,000
new cus tomers .Load control programs are expected to become
a valuable part of the portfolio, but Idaho Power will still
need the Danskin Power Plant to reliably meet peak loads.
Does Idaho Power Company operate the Danskin
Plant to profit from off-system sales?
The Danskin Power plant was built to supply
native load.However, like any generating resource, Idaho
Power has the option to run the Danskin plant during times
when the energy from the plant is surplus and can be sold at
a profit.In those cases, the bulk of the profits would be
returned to the Idaho Power customers through the annual
Power Cost Adjustment.
Dr. Reading s testimony focuses on the high
costs of the Danskin Power Plant.How do you explain those
costs in terms of the decision to build and operate Danskin?
First, no one should be surprised that the
per MWh cost of a peaking plant is greater than a base load
plant.Second, as the Commission noted in Order No. 28733
when it issued the Certificate of Public Convenience and
Necessi ty for Danskin, the standard for evaluating the
decision to proceed with Danskin must be viewed in the
PRESCOTT, Di-Reb
Idaho Power Company
When the decisioncontext of the facts known at that time.
to build Danskin was made the market price of power was
high.In February of 2001 Mid-Columbia forward prices for
August through December 2001 were $350 - $415/MWh for heavy
load hours, and $275 to $300/MWh for light load hours.
Therefore, Danskin was considered valuable for its peaking
attributes and for its "in the money " status which would
have served to lower power supply costs to the retail
Gi ven these forward prices, Danskin would havecustomer.
likely operated at full load for the remainder of 2001.
fact, given gas and power prices in the winter of 2001,
Danskin s operation could have reduced net power supply
costs to Idaho Power s customers by about $15 million
dollars per month.Gi ven these market condi tions and Idaho
Power s potential exposure, a down payment on the turbines
was made in early February 2001 and the purchase was
completed by mid-March 2001. The market subsequently changed
but the proj ect was continued based on the need for a true
peaking resource.
Dr. Reading is critical of the Company
estimates of the number of hours Danskin will operate.
this criticism valid?
The decision to build Danskin was drivenNo.
by the fact that the Company has an obligation to serve its
customers even if inbound transmission constraints blocked
PRESCOTT, Di-Reb
Idaho Power Company
access to the open market during peak times.Therefore the
decision to build and operate Danskin was a low cost option
to maintain continuity of service and reliability during
those peak times when inbound transmission was unavailable.
In other words the attributes of a peaker made Danskin a
cost effective solution to the problem, i. e. a resource that
has a relatively low capital cost, relatively high operating
costs and a low capacity factor are desirous qualities.
. asking ratepayers to assume theReadings comment
costs of a plant that will sit idle most of the time
is misleading when considered in the context of the
The operation of a fire truck is andefini tion of a peaker.
analogous example to a peaker.It sits idle most of the
time but has a specific purpose of being ready to respond to
infrequent but critical situations.
Dr. Reading testifies that the Company should
have cancelled the Danskin Power plant in the summer of
2001.Would it have been prudent for the Company to cease
construction of the proj ect after power prices dropped in
the summer of 2001?
There are several reasons why it would not
have been prudent or reasonable for Idaho Power to cease
Danskin construction as Dr. Reading now recommends.First,
Dr. Reading simply glosses over the fact that at the time
wholesale prices dropped in the summer of 2001 there was
PRESCOTT, Di-Reb
Idaho Power Company
still tremendous uncertainty in the Western electricity
markets.While looking backward from today shows that
wholesale prices began decreasing in June of 2001, the
forward prices at that point were still abnormally high.
And forward price predictions were all the information that
was available in June of 2001.Addi tionally, there was
considerable uncertainty as to how long the FERC-imposed
price caps would remain in place and what affect their
removal might have on market prices.Second, when one
considers the extremely adverse water conditions that
existed in the fall of 2001, canceling a generation resource
in the face of a very uncertain wholesale market and
transmission constraints would have been very risky.
short, without the benefit of Dr. Reading s 20/20 hindsight,
I believe it would have been extremely imprudent to abandon
Danskin in midstream as Dr. Reading urges.
In addition to the operating risk of
cancellation, would there have been financial ramifications
of cancellation in mid-stream?
Of course.By the end of June 2001 Idaho
Power had already incurred approximately $33.5 million in
costs associated with the Danskin Power Plant.Tha t amoun t
represents approximately 65 percent of the total cost of the
proj ect .In addition, cancellation would have obligated the
Company to pay substantial cancellation charges to various
PRESCOTT, Di-Reb
Idaho Power Company
contractors.Considering the uncertainty in water
conditions and the wholesale power markets at the time, and
considering the fact that approximately two-thirds of total
project costs had been incurred, plus the additional costs
that would be incurred to terminate the proj ect, Dr.
Reading s suggestion that the Company should have cancelled
the project and then requested recovery of the costs from
customers is patently unreasonable.
What would be the consequences of the Danskin
Power Plant being excluded from ratebase and removed from
service as suggested by Dr. Reading?
I am not qualified to address the ratemaking
and legal ramifications of such a decision.Mr. Gale and
Mr. Ripley will address those issues.I can say that as the
officer in charge of resource adequacy for Idaho Power, that
going into the summer of 2002 without Danskin, the Company
would have significantly increased the risk of breaching its
NERC reserve requirements and significantly increased the
risk of service curtailment.In fact, during the 2003 peak
summer season, even with Danskin running at full output, the
Company was unable to maintain its desired reserve margins
during some heavy load hours, meaning that a single system
contingency would have required service curtailments.
Are there other system benefits Danskin
provides besides meeting peak load demand?
PRESCOTT, Di - Reb
Idaho Power Company
Yes.Having a generating resource providing
vol tage support close to the load center of the Treasure
Valley helps to prevent a phenomenon known as voltage
collapse.This happens during periods of peak customer
demand when load is being served by generators remote to the
load center since the reactive power necessary to maintain
voltage is difficult to transmit over long transmission
lines.
Danskin also provides emergency reliability for the
system in the case of unplanned outages.
On page 5 of Dr. Reading s testimony, at
lines 19 and 20, Dr. Reading states that the variable costs
of power produced from Danskin has varied between 60.2 cents
per kWh in 2001 and 29.7 cents per kWh in 2002.This seems
qui te high.Please comment on this?
I believe Dr. Reading inadvertently included
Danskin s fixed costs in those calculations.In general,
Danskin s variable costs of production can be approximated
by multiplying the delivered fuel cost in $/MMBtu by the
plant heat rate of approximately 12 MMBtu/MWh.So, for
$4/MMBtu gas, the variable cost of operating Danskin would
be $48/MWh or 4.8 cents per kWh.In reality, we would add
several $ /MWh for variable O&M costs, but this approximation
is close.
Did Danskin operate effectively to carry
PRESCOTT, Di-Reb
Idaho Power Company
customer loads during the peak summer months in 2002 and
2003 ?
Yes.During July of 2002 Danskin s units
operated a total of 481 hours and during July of 2003
Danskin was operated a total of 567 hours.
Did Idaho Power depend on Danskin to serve
its peak loads during the summers of 2002 and 2003?
Absolutely.In fact, if the Danskin plant
had not been in-service and on-line during those peak
months, Idaho Power might not have been able to meet its
cus tomers peak loads.
What is your future expectation for the
opera tion of Danskin?
Danskin will continue to dispatch to meet
peak loads and for reliability during the summer of 2004 and
beyond.While it is true that with the addition of the new
Bennett Mountain CT Danskin may dispatch less, it will still
dispatch during peak times when transmission constraints are
encountered, especially as peak load grows over time.
Summer peak load is growing on the order of 80 to 85 MW per
year as illustrated in Figure 2 below.
PRESCOTT, Di-Reb
Idaho Power Company
Figure 2. Forecasted Firm Summer Peak
Forecasted Firm Summer Peak
(megawatts)
4200
000
1980 2015200520101985199019952000
Preliminary 2004 Integrated Resource Plan results
indicate that peak hour transmission deficits from the
Pacific Northwest continue to grow.Even wi th Danskin and
Bennett Mountain plants in operation, the projected peak
hour transmission deficits from the Pacific Northwest reach
510 MW in 2010, and continue to grow in subsequent years.
Given the proj ected peak hour transmission deficits, it is
anticipated that the 2004 IRP will show a need for even more
peaking resources located inside of the Company s control
area near the load.
WOODHEAD PARK
Staff Witness Leckie recommends that the
Commission defer the Company s $7,525,237 investment in
PRESCOTT, Di-Reb
Idaho Power Company
improvements made to Woodhead Park and include that amount
in Hells Canyon Complex relicensing costs for recovery in
the future.Recognizing that Idaho Power witness Gale will
address the ratemaking aspects of Mr. Leckie
recommendation, can you briefly explain why Idaho Power
invested in a substantial renovation of Woodhead Park?
Mr. Leckie correctly notes that as a
condi tion of the Company s existing license, the FERC
requires that Idaho Power optimize and provide adequate
recreational opportunities for the public.Thus, Idaho
Power must adapt to changing needs for recreational and
other facilities on an ongoing basis throughout the license
period.
Crappie angling and harvest on Brownlee Reservoir
peaked in the late 1980' s resulting in much more regional
attention (via newspaper articles, word-of-mouth, etc.) and
more demand on the Company s recreational facilities in
Hells Canyon.In 1989, the Idaho Department of Fish and
Game reported that Brownlee Reservoir was the most popular
fishing pond in the state.It was estimated to have had
851,749 hours of angling effort, as compared to 400,000
hours at the next most popular, Cascade Reservoir.Fishing
and associated camping was the most popular recreational
activity in the Hells Canyon Complex (HCC).
Woodhead Park is Idaho Power s only park on Brownlee
PRESCOTT, Di - Reb
Idaho Power Company
Reservoir.It was the least developed of all Idaho Power
camping facilities in the HCC.Woodhead Park was built in
the 1950's and not designed for large RVs, campers, boats
and trailers that were in use by the 1980' s.By 1990 the
amount, type and needs of users had far surpassed the
facili ty ' s physical and functional capabilities.Because of
this situation, the park was very congested, especially on
weekends and holidays.The Company received expressions of
concern from the public and special user groups (bass clubs,
etc) .
Immedia te modern upgrades were needed.In order to
meet public expectations, upgraded facility requirements
included:a dependable and more consistent potable water
supply a wider and longer boat ramp with docking system and
adequate parking for trailers and vehicles restrooms to
replace the existing pit toilets (all other parks had
restrooms with showers) a fish cleaning station instead of
using garbage cans and upgraded electrical hookups.
Also, new federal regulations, i.e., the Americans
With Disabilities Act required changes to accommodate the
physically handicapped.Original Woodhead Park facilities
were not compliant.
Woodhead Park reconstruction was completed in 1996.
All features and facilities are utilized by the public.
Are the improvements at Woodhead Park
PRESCOTT , Di-Reb
Idaho Power Company
extensively used by the public?
Yes.In 2001, usage statistics fee use
envelopes indicate 28,042 people camped at Woodhead Park.
This figure does not include day-use, which is mostly
associated with the boat ramp and fish cleaning facilities.
Mr. Leckie argues that the investment in
Woodhead Park improvements should be deferred because it is
tied to relicensing of Hells Canyon Complex.Did upgrading
Woodhead Park help reduce the potential demands and costs
associated with relicensing?
While the primary motivation for the
improvements was compliance with the existing FERC license,
in addition to meeting usage demands at the time, there is
no question that a significant benefit of rebuilding the
facili ty prior to relicensing was to demonstrate
responsiveness to public needs and moderate requests for
addi tional facilities at Woodhead Park during the
relicensing process.Idaho Power believes the Memorandum of
Understanding with Idaho Department of Parks and Recreation
IDPR") achieved this objective, as IDPR did not request
additional facilities other than what was mutually agreed
upon and proposed in the Final License Application for the
new HCC license.
Mr. Leckie notes that the rate-based costs of
the Woodhead Park project are greater than originally
PRESCOTT, Di-Reb
Idaho Power Company
estimated in the Revised Exhibit R filed with the FERC in
November of 1990.Explain why the actual costs to renovate
Woodhead Park are greater than the costs estimated in the
Company s November 1990 FERC filing.
The anticipated costs noted in the revised
Exhibit R, $4 to $5 million, were based on preliminary
concept designs and estimated construction costs.The pre-
bid estimate, based on final design, was $6 million.
Bidding for the work was very competi ti ve, wi th minimal
difference between the three lowest bidders.The post-bid
estimate of $6.8 million included Idaho Power overheads,
interest during construction and adjustment for a pre-bid
estimate error in quantity of paving.Because of low
streamflow conditions in 1992, Idaho Power negotiated a
contract modification and deferred for a year most of the
planned 1992 and 1993 construction activities to minimize
drought-year costs.The deferral contributed to final costs
exceeding earlier estimates.
Why is the Woodhead Park improvement
investment being depreciated over a period longer than the
existing license?
Though existing license obligations, as noted
previously, caused Idaho Power to upgrade Woodhead Park, the
improvements have a useful life extending beyond the license
period.Idaho Power routinely makes prudent reinvestments
PRESCOTT, Di-Reb
Idaho Power Company
in its facilities based on the "going concern " assumption.
It is assumed that Idaho Power will continue operating into
the future and new licenses will be issued to support that
operation.Consequently, capital investments depreciate
over their useful life, regardless of the license period in
whi ch they were made.Capitalized costs incurred in
obtaining a new license are the exception and their
depreciation period matches the license period.
Does the Staff recommendation to exclude
Woodhead Park investment comply with standard regulatory
accounting practices?
I know that the term "used and useful" has a
specific meaning in regulatory practice.Speaking as an
engineer, there is no question that the Woodhead Park
improvements are complete, used and useful.In keeping wi
the regulatory compact, it seems to me that prudent
investments that are currently used and useful should
included in rate base.Excluding the investment from rate
base until HCC relicensing costs are addressed ignores the
fact that the improvements were done to meet current license
requirements, meet current public needs, and are fully used
and useful now.
Mr. Leckie recommends that the Company
investigate increasing user fees at Woodhead Park.Why not
raise the park fees to cover annual operation and
PRESCOTT, Di-Reb
Idaho Power Company
maintenance expenditures?
The FERC allows licensees to charge
reasonable fees to help defray the cost of operation and
maintenance of park facilities.Idaho Power sets fees based
on rates at comparable facilities and the public
willingness to pay.The Company reassesses its user fee
structure periodically and will increase fees consistent
wi th the above-described cri teria
Are there any other concerns you have wi
Staff's recommendation on Woodhead Park investment?
I believe that at a time when we are working
hard to build needed public support for relicensing the
Hells Canyon Complex, it is counterproductive to discourage
investment in visible, desirable and appropriate
improvements in recreation facilities in Hells Canyon.
BIOLOGICAL OPINION
Staff Witness Leckie recommends that the
Commission remove $654,740 from the Company s rate base
attributable to capitalized expenses the Company incurred in
defending against a Sierra Club lawsuit relating to a
National Marine Fisheries "Biological Opinion.Is Mr.
Leckie s characterization of the facts surrounding the
biological opinion issue correct?
It is not entirely correct however, I can
understand how Mr. Leckie could misinterpret the facts
PRESCOTT, Di - Reb
Idaho Power Company
surrounding the expenditure of costs for this matter because
the facts are complex and his review was apparently limited
to a brief summary of the facts provided by the Company in
response to a Staff audit request.Nevertheless, to fully
understand this matter, some additional explanation is
needed.
In the early 1990' s the National Marine Fisheries
Service ("NMFS" , now referred to as "NOAA Fisheries " or
NOAA") listed several stocks of anadromous fish that
inhabit the lower Snake and Columbia Rivers under the
Endangered Species Act ("ESA"The Snake River sockeye
listed as endangered in 1991 and spring/summer and fall
chinook as threatened in 1992. Since those ESA listings, the
Pacific Northwest has been engaged in a conflict over the
sustainable use of the natural resources that influence the
listed species, including the water resources of the State
of Idaho. Idaho Power finds itself in the middle of this
controversy largely because it owns and operates 14
hydroelectric plants on the Snake River that are situated
geographically between the upper Snake River Bureau of
Reclamation (BoR) storage reservoirs and the four lower
Snake River Federal dams that many consider to have brought
the region's anadromous fish resources to the brink of
extinction. The largest of the Company s facilities, and the
one closest to the habitat of the listed species, is the
PRESCOTT, Di-Reb
Idaho Power Company
Hells Canyon Complex.
In March 1997, the Sierra Club Legal Defense Fund,
on behalf of several environmental groups, sent a "notice of
intent to sue " for violation of the ESA to FERC and NMFS
threatening to file suit pursuant to ~ 11 (g) of the ESA if
FERC did not initiate consultation with NMFS regarding the
effect of ongoing operations of the HCC on ESA listed
anadromous fish. Thus began a long and complex legal and
technical battle over the alleged effect of operations at
the HCC on the listed species.
Why was this action of such great concern to
Idaho Power?
The environmental groups were attempting
through this action to force the FERC to reopen the
Company s existing license for the HCC, and impose
operational changes to address alleged effects on the listed
species.Many of the changes supported by the environmental
groups would significantly reduce operational flexibility
and potentially impose millions of dollars in additional
operational costs and were not supported by scientific
research.These costs would have begun in the year imposed
and continue each year throughout the remaining term of the
existing Hells Canyon Complex license and until a new
license is issued. The operational changes and associated
costs, if imposed, would likely also continue into and
PRESCOTT, Di-Reb
Idaho Power Company
through the term of the new license.
Why did Idaho Power Company capi talize the
costs associated with defending the Hells Canyon Complex
license and its operational flexibility in this Biological
Opinion matter?
As noted previously, the intent of the
environmental groups ' lawsuit was to force FERC to reopen
the current Hells Canyon Complex license and incorporate
restrictive modifications.Idaho Power s successful defense
of the integrity of the current license prevented negative
impacts to revenues and expenses in the test year as well as
years into the future.The multi-year benefit was one
factor for capitalizing the costs.
The Company s interpretation of CFR 18 Electric
Plant Instruction 3.8 and CFR 18 Electric plant Instruction
15 support the selected accounting treatment.The Company
also considered the accounting treatment the Commission
approved for the Nez Perce settlement case, which is
factually similar and cites the same CFR provisions, as
providing guidance and precedent for the capitalization
decision in this case.
What is the depreciation schedule for the
investment?
Costs to defend the operating integrity of
the license benefit the remaining life of the existing Hells
PRESCOTT, Di-Reb
Idaho Power Company
Canyon Complex license.The benefit will likely extend into
the period of annual licenses issued until the relicensing
process is complete and a new multi-year license is issued.
It is difficult to estimate how long the relicensing process
will take, but a conservative estimate is three years beyond
expiration of the current license.Therefore, a
depreciation period of 52 months (March 2004 through June
2008) is being used for the investment.The start of the
depreciation was delayed due to a misunderstanding regarding
the Biological Opinion s costs and their link to HCC
relicensing.Based on this schedule, monthly depreciation
expense is $12,591 annual depreciation is $151,092.
Do you have any final thoughts on this issue?
It seems clear to me that this investment
will have a long-term positive effect on the Hells Canyon
Project and should be included in the Company s rate base.
CLOUD SEEDING
Staff Witness Hessing testified that
additional information is needed for the Staff and
Commission to adequately assess the reasonableness of
including expenses associated with the Company s ongoing
cloud seeding program in test year expenses.Could you
please address the Company s ongoing cloud seeding program?
Yes, I can.In his testimony Mr. Hessing
poses four questions relating to cloud seeding.In my
PRESCOTT, Di - Reb
Idaho Power Company
response I will initially respond to Mr. Hessing
characterization that cloud seeding is experimental and
somewhat controversial, and then I will answer his four
questions in the order posed.
On page 24 of his testimony Mr. Hessing
states that "Given the experimental and somewhat
controversial nature of cloud seeding programs
cloud seeding experimental?
There is no question that cloud seeding is
somewhat controversial and experimentation is ongoing.
However, cloud seeding has gone beyond the experimental
stage.Experimentation continues in the field of weather
modification, but the field is no more "experimental" than
say, an experimental aircraft.It works, but there is room
for improvement.While admittedly there is controversy, the
World Meteorological Organization, the American
Meteorological Society, the Weather Modification
Association, and the American Society of Civil Engineers all
acknowledge or have published statements indicating a
properly conducted cloud seeding proj ect can produce
significant results.
Idaho Power s interest in cloud seeding is to
augment snow pack, and ultimately hydroelectric generation.
Due to the interest in snow, the project focuses on
wintertime cloud seeding.Idaho Power recognizes that to be
PRESCOTT, Di-Reb
Idaho Power Company
effective, a cloud seeding project must be properly
Idaho Power has and is making signi ficantconducted.
efforts to ensure that the proj ect is properly conducted to
assure the anticipated benefits.
Mr. Hessing s first question is:What
acti vi ties constituted the cloud seeding program in past
years, including the test year, and what are the Company
cloud seeding plans for upcoming years?Please answer this
question.
Idaho Power began investigating whether or
not cloud seeding might be a beneficial tool in the early
1990'By 1995, there was enough positive evidence to
convince the Company to make a focused investigation as
the "meteorological receptiveness " of the Payette River
Basin to cloud seeding efforts.In conjunction with the
Desert Research Institute ("DRI") , an adjunct of the
University of Nevada, the weather and climatology of the
area were investigated.Tha t inquiry provided the impetus
for what can be considered the "seeding program in past
years. "
A contract was awarded to Atmospherics Incorporated
(AI, Fresno, CA) for an operational cloud seeding effort
the Payette River Basin during the winter of 1996-97.The
winter got off to an extremely warm and wet start.
Therefore, the effort was suspended in December 1996.
PRESCOTT, Di - Reb
Idaho Power Company
Following the suspension of operations in 1996, the
Company continued to evaluate cloud seeding.The evaluation
addressed two general areas of interest.First, the Company
kept abreast of existing and new cloud seeding proj ects,
Second, the evaluation focusedresearch and developments.
on assessing the rewards and/or risks to shareowners that
resul t from funding a proj ect with the purpose of reducing
power supply costs with no clear regulatory mechanism to
equitably share the project costs and benefits between
shareowners and customers.Following several years of
evaluation and discussions with Commission Staff regarding
project cost, rewards and risks, the Company committed to an
in-house project in 2002.
In 2002 the Company hired a full-time meteorologist,
Working wi th experienced in wintertime cloud seeding.
consultant who had been active in researching and designing
the project, an operational program was again initiated in
late January of 2003.Seeding began on February 1 and
continued, when opportunities arose, until April 15, 2003.
During that time, an aircraft specially modified for cloud
seeding and contracted from Weather Modification, Inc.(WMI)
of Fargo, ND flew for 22.3 hours and seeded for 15.4 hours,
releasing 23,207 grams of seeding material (silver iodide,
AgI) .A network of six ground-based generators operated for
514.5 hours and released an additional 10,288 grams of AgI.
PRESCOTT, Di-Reb
Idaho Power Company
During the operational period, fifty-five weather balloons
were released within the watershed for operational and
research uses under a contract with Technical and Business
Systems, Inc. of Santa Rosa, CA.
Given favorable meteorological conditions, the plan,
calls for an in-depth evaluation phase over the current and
the next winter seasons.A specially modified aircraft,
again acquired through a contract with WMI, releases both a
tagged seeding agent (mixed AgI and cesium iodide (CsI) and
an inert tracer that has indium (In) as the key ingredient.
A second aircraft, available for approximately two weeks and
modified for cloud physics research, will take samples of
the aerosol and particle size spectra, measure in-cloud
moisture content, and several other parameters to refine
seeding procedures and the formulae used for the seeding
ma terial Weather balloons will again be released from
wi thin the watershed.Unlike last season, this task has
been assumed by the proj ect personnel, rather than
undertaken as a contracted service.The ground-based units,
again consisting of six locations, each have two generators,
one releasing AgI, the second, the In tracer.This
combination will allow for sophisticated analyses of the
trace chemistry and help identify the relative impact and
merit of the two delivery methods (ground and aircraft)
Detailed density analysis of the snow samples will provide
PRESCOTT, Di - Reb
Idaho Power Company
an indication of project yield and effectiveness.posi ti ve
results from this investigation, being conducted by DRI, are
expected to support an on-going proj ect.Negative results
for the aircraft or ground based component that cannot be
adequately explained will likely lead to cancellation of
that piece of the program.
The DRI has initiated work this winter to evaluate
the project using trace chemistry.Two sampling expeditions
have been completed so far and samples from the first
expedi tion have been analyzed.Preliminary results from the
first expedition show that the snow pack at three sites in
the basin contain layers containing significant amounts of
silver.These layers are also enriched in silver relative
to the rest of the snow pack suggesting some contribution
from silver iodide.Estimates of the deposition dates of
the enriched layers are consistent with the records of
silver iodide releases from the ground and aircraft silver
iodide genera tors.The first expedition took place prior to
releases of cesium and indium and found an extremely low
background for these elements (at the parts per quadrillion
to parts per trillion level), which means that the
determination of the tracers will be unambiguous.
Additional information regarding the preliminary results can
be found in Exhibit 69 to my testimony.
Mr. Hessing's second question is:What
PRESCOTT, Di-Reb
Idaho Power Company
cri teria will the Company use to determine the level of
cloud seeding activity and expenditures necessary in any
given year?Please answer this question.
The level of seeding activity will vary with
During dry years, fewerthe weather of the given season.
opportuni ties will arise (fewer storm systems), but they
will need to be worked for whatever benefit can be gained.
Expenditures might be somewhat lower during these years, but
the reduction is not expected to be significant because of
the extra effort involved in seeding any and all storm
During wet years, initial activity will be highsystems.
because of more frequent opportunities, but at the same
time, it becomes more likely that the project's suspension
cri teria will be met or exceeded, leading to a secession of
Hence, there would be higher costs early in theactivity.
season and a significant reduction later.During a normal
winter, operations would be expected to be at or near the
budgeted level.In summary, costs should remain relatively
steady once the proj ect is through the startup and
evaluation phases.
Mr. Hessing s third question is:How does
the Company evaluate whether cloud seeding works and that
Please answer this question.the benefits exceed the costs?
The evaluation phase of the Proj ect calls for
a sophisticated trace chemistry and snow density analysis,
PRESCOTT, Di-Reb
Idaho Power Company
as outlined above.These analyses will allow Idaho Power
evaluate the relative effectiveness of the two delivery
systems and differentiate between snow that would have
fallen naturally and that which resulted due to seeding.
The differences will allow a quantitative evaluation of how
much snow was produced during each seeding event and over
A copy of preliminary resul the course of the season.
from the trace chemistry analysis performed by the Desert
Research Institute is attached as Exhibit 69.
Under the original project plan, no evaluation of
effectiveness was intended during the first, start-up year.
However, pending the results of the trace chemistry
analysis, a preliminary, target/ control statistical analysis
was conducted by Idaho Power personnel not involved in
(This analysis was indirectly confirmedseeding decisions.
by a similar analysis of seeding activity on the adjacent
Boise River watershed by North American Weather
Consul tan t s) .The results indicate that the seeding
activity during the winter of 2002-03 resulted in a 13-
percent increase in precipitation in the Payette River Basin
The most likelyduring the time frame of active seeding.
yield is 15-16 percent.That would equate to approximately
110,000 acre-feet of water that would subsequently produce
55,000 MWh of electricity at Idaho Power s Hells Canyon
Using the average market price of electricity forComplex.
PRESCOTT, Di-Reb
Idaho Power Company
2003, the value of that power would be on the order of $1.
million, giving a benefit/cost ratio of -1.5: 1 for the
startup phase and a relatively brief period of seeding
opera tions Once the costs associated with the evaluation
phase (note that costs associated with assessment were not
incurred during 2003 test year) are removed from the budget,
assuming a conservative ten percent increase in
precipitation yields a benefit/cost ratio of -4:1 given
hydrologic conditions of 80 to 120 percent of normal
precipitation.
Mr. Hessing s last question is:Wha t would
be the effect on the Company s cloud seeding program if the
Commission denied recovery of the costs requested in this
case?Please answer this question.
Idaho Power believes that a properly operated
cloud seeding program will be a cost effective means of
increasing generation at existing hydroelectric facilities.
Conservative projections for a fully implemented project
indicate a benefit cost of -4: 1, and that the cloud seeding
project will provide on average 80,000 MWh of generation per
Initial indications as discussed above are that theyear.
project provided a positive benefit the first year, even
wi th a shortened operating period and expenses associated
wi th startup and implementation.And, as set out in Exhibit
69, indications are that the proj ect is having a posi ti ve
PRESCOTT, Di-Reb
Idaho Power Company
benefi t on snow pack the second year as well.Efforts are
currently underway to assess the effectiveness of the
project using trace chemistry and airborne cloud physics
analysis.Resul ts from the assessment are expected to
demonstrate the effectiveness of the project, and provide
information useful to further refine the proj ect
configuration and operations.However, even wi th a very
attractive benefit cost ratio, without the ability to
recover costs on an ongoing basis, it is likely that Idaho
Power would not continue to pursue cloud seeding as a water
management tool and as a means of offsetting the need to
acquire additional generation.
Does this conclude your direct rebuttal
testimony?
Yes.
PRESCOTT, Di - Reb
Idaho Power Company
BEFORE THE
IDAHO PUBLIC UTiliTIES COMMISSION
CASE NO. IPC-O3-
IDAHO POWER COMPANY
EXHIBIT NO. 69
J. PRESCOTT
2003-2004 Cloud Seeding Program
..-'". /--~/ ',,"'\ -- ..--
"0 -
Figure 1 Map of snow sample site location, ground generators and SNOTEL sites.
The map shows the target area bounded by a red line, triangles = sampling sites, flags = SNOTEL sites and
blue pins = ground generators.
Sample preparation and chemical analysis
Silver, indium and cesium in the target area snow pack are present at the parts per trillion
level (10-12 g g ) requiring both ultra-trace clean techniques and extremely sensitive
analytical methods. The Desert Research Institute Ultra-trace Chemistry Laboratory
routinely analyzes snow and ice samples from Antarctica and Greenland (the purest snow
in the world) and is one of several laboratories in the world capable of making ultra-trace
elemental analyses in snow. The Ultra-trace Laboratory consists of a class 100 clean
room, two adjacent wet chemistry laboratories and a sample preparation freezer (-160 C).
The clean room (Fig. 1) houses a high-resolution inductively coupled plasma mass
spectrometer (HR-ICP-MS), an inductively coupled plasma optical emission
spectrometer (ICP-OES), and an ultra pure water system (18.2 MQ).
Silver, indium, cesium and aluminum are being determined in the snow samples by high
resolution inductively coupled plasma mass spectrometry. The main advantageous of this
method are that it requires minimal sample preparation and has detection limits in the
Exhibit No. 69
Case No. IPC-03-
J. Prescott, IPCo
Page 6 of 10
Preliminary Results of the IPCo 2003-2004 Cloud
Seeding Program Trace Chemistry Evaluation
P. Ross Edwards1
Arlen Huggins2
Joseph McConnell1
March 2004
;2 t1-03/15/2004
DateP. Ross Edwards
Exhibit No. 69
Case No. IPC-03-
J. Prescott, IPCo
Page 2 of 10
Preliminary Report for the IPCo Operational Seeding Program Trace Chemistry
Evaluation
Executive Summary
As part ofthe Idaho Power Company s Cloud seeding assessment for 2003-2004 we have
been conducting a trace chemical evaluation of the snow pack in the Upper Payette River
Basin. The evaluation is based on the detennination of silver, indium, cesium and
aluminum in the snow pack at seven sites including a control site outside the basin.
Indium and cesium are being released along with silver iodide in order to discern between
aircraft and ground based releases of silver iodide and to determine whether the silver
present in the snow pack is due to ice nucleation or other processes. Aluminum
comprises some 8% of the earth's crust and is being determined in order to calculate
whether the silver found in the snow is enriched relative to background inputs from soil
and dust.
Two sampling expeditions have been completed so far and samples from the first
expedition have been analyzed. Preliminary results from the first expedition show that
the snow pack at three sites in the basin contain layers containing significant amounts of
silver. These layers are also enriched in silver relative to the rest of the snow pack
suggesting some contribution from silver iodide. Estimates of the deposition dates of the
enriched layers are consistent with the records of silver iodide releases from the ground
and aircraft silver iodide generators. The first expedition took place prior to releases of
cesium and indium and found an extremely low background for these elements (at the
parts per quadrillion to parts per trillion level), which means that the determination of the
tracers will be unambiguous.
Samples from the second expedition will soon be analyzed. Both indium and cesium
tracers were being released during the time that these samples were deposited and their
analysis will give a clearer indication of the silver sources and impact on the snow pack
water content.
Exhibit No. 69
Case No. IPC-03-
J. Prescott, IPCo
Page 3 of 10
Preliminary Report for the IPCo Operational Seeding Program Trace Chemistry
Evaluation
Overview of the trace chemistry evaluation
The Trace Chemistry Evaluation (TCE) component of the seeding program aims to
investigate the presence of ice nucleating and non-ice nucleating tracer elements in the
target area s snow pack. Targeting efficiency, seed source (ground vs aircraft) and the
transfer of the seeding species to the snow pack by ice nucleation and scavenging are
being assessed from the presence of silver (ice nucleating element), an indium tracer
(non-nucleating element) and a cesium tracer (aircraft). Indium has been used in several
wintertime cloud seeding research and operational projects to evaluate seeding
effectiveness. Examples are the Pacific Gas and Electric Lake Almanor Project
(Warburton et al., 1995a; Chai et aI., 1993) and the NOAA-Nevada Atmospheric
Modification Program (Warburton et aI., 1996a; Warburton et aI., 1996b). As indium has
little impact on ice nucleation (but is present as insoluble particles in the same size range
as silver iodide) the atmospheric transfer of indium to the snow pack is solely by
processes collectively known as scavenging. Scavenging has no impact on the
enhancement of precipitation, but may also transfer some silver to the snow pack and
thus must be evaluated in order to determine the amount of silver incorporated into the
snow by ice nucleation and hence the seeding effectiveness.
Cesium has been used in previous TCE's to distinguish between aircraft and
ground based silver iodide releases. The Southern California Edison (SCE) cloud
seeding project in the San Joaquin Basin of the southern Sierra Nevada was one of the
first to evaluate an operational seeding project using both cesium and indium tracers
(McGurty, 1999). In addition to silver iodide releases from the ground and air, cesium
was used in ground generators, while indium was dispensed from aircraft generators.
Trace chemical evaluation ofthe area s snow pack was used to determine the targeting
effectiveness of the two seeding methods. The SCE program also made use of a
detectable difference in the snow densities of seeded samples (greater density) and
unseeded samples, to estimate the amount of water that was added to the snow pack by
seeding operations.
Natural sources of silver, indium and cesium also exist and need to be
investigated. For example all of the tracer elements are also present in soil and dust at
very low levels, which may be incorporated into the snow. In order to evaluate natural
inputs, aluminum and other soil and dust tracers are being determined and used to
estimate variations in silver, indium and cesium enrichments. Equation 1. is commonly
used to calculate an elemental enrichment factor, which is proportional to the ratio of the
element of interest to aluminum in the snow divided by the average ratio of the element
to aluminum in the Earth's crust. Based on this equation an EF of one would equal no
enrichment relative to the Earth's crust, however significant regional variations do exist
(for example silver ore is highly enriched) and silver EF's on the order of 100 -1000 are
not uncommon. Therefore the TCE is investigating variations in EF's and not the
magnitude.
Exhibit No. 69
Case No. IPC-O3-
j, Prescott, IPCo
Page 4 of 10
Equation 1. Enrichment factor
EF
(Element crustal.1racer).now
Element (Element crusta .1racer Ear/hs..Crost
The experimental design of the IPCo TCE has 6 components:
1. Ground and aircraft releases of silver iodide and additional tracers
2. Snow sampling expeditions to established sites within the target area and a control
site out side ofthe target are.
3. The ultra-trace analysis of snow samples for silver, cesium, indium and aluminum
and estimation of enrichment in respect to the average composition of the Earth'
crust.
4. Estimation of targeting and targeting effectiveness based on snow silver, indium,
and cesium concentrations and enrichments.
5. The investigation of snow pack density variations in relation to silver
concentrations, enrichment and silver / indium ratios.
6. The construction of maps of targeting, targeting effectiveness and enhancement of
snow pack density.
Sample Site Selection and Technical Approach
Site location and field expeditions
Seven snow pack sampling sites, including one control site, were selected based on target
area coverage, altitude
(:::-
6000 ft), proximity to the SNOTEL stations (Jackson Peak
Banner Summit, Deadwood Summit and Big Creek Summit) and the availability of
helicopter landing sites. The sites, MZ, Tl, T2, T3, T4, T5 and control site OTI are
shown in Figure 1. The SNOTEL data available for these sites may be used to determine
specific stonn periods from the snow profiles. Two snow poles with snow boards were
placed approximately 20 ft apart at each site in November 2003. The snow sampling plan
calls for four repeat sampling expeditions during the seeding season with the goal of
collecting two snow chemistry profiles at each site. Sample collection procedures are
similar to those used in the 1996 IPC program (Warbuton, et aI., 1985) and include
procedures to prevent contamination of samples by personnel and helicopters.
Additional physical measurements (profiles of the snow pack density and stratigraphy) of
the snow pack are conducted in snow pits. The sampling program also includes a quality
control program that mandates the use of field and laboratory blanks and recovery
standards. All snow samples are kept frozen until analysis at the Desert Research Ultra-
trace Chemistry Laboratory.
Exhibit No. 69
Case No. IPC-03-
J. Prescott, IPCo
Page 5 of 10
DRI
Desert Research Institute
Trace Chemistry Evaluation of the IPCo
2003-2004 Cloud Seeding Program
Preliminary Results from the January 2004 Sampling Expedition
Exhibit No, 69
Case No. IPC-O3-
j, Prescott, 'PCoPage1of10
parts per quadrillion range (10-15 g g ) for many elements. Sample preparation consists
of adding a known amount of an internal standard (yttrium) to the sample melt water.
Preliminary Results
To date two sampling expeditions have been completed. The first expedition was
conducted in January 2004, before the deployment of the indium and cesium tracers. The
aim of this expedition was to make a preliminary analysis of silver at the sites and to
establish background levels of cesium and indium. Some problems were encountered
due to poor weather conditions and a high dust loading in snow at the control site aT!.
Preliminary results for silver are shown in Figures 2. and 3.
110
100
100 200
150
..-..
100
....
20 40 60 80 100 20 40 60 80 100
Snow Depth (em)
Figure 2 Silver concentrations for Sites T2, T4 and MZ as a function of snow depth
Exhibit No. 69
Case No, IPC-O3-
J. Prescott, IPCo
Page 7 of 10
7000
6000 5000
6000
5000
4000 5000
c::
E 4000
.t::.40003000
c::
..... 3000 3000
(/)
2000
2000 2000
1000
1000 1000
0 20 40 60 80 100
Snow Depth (em)
0 20 40 60 80 100
Figure 3 Silver enrichments for Sites T2, T 4 and MZ as a function of snow depth
Significant silver layers were found in the snow pack at sites T2, T4 and MZ are labeled
1- 6. In general the silver layers also had the highest enrichment values (up to 6000)
suggesting that silver iodide releases were the likely source. Stonn dates for different
sections of the snow pack were estimated using snow depths, densities and near by
SNOTEL data. An example storm/snow depth reconstruction is shown in Figure 4.
Estimated dates for the events are shown in Table 1. There are several differences
between the three sites giving some indication of the targeting effectiveness. For
example event 2 is the only significant event to impact all sites and the only event
deposited to MZ. Atmospheric transport modeling will be required to describe event 2
which appears to be the most wide spread event.
Cesium and Indium were also detennined in samples from the first field
expedition and found to be present at the parts per quadrillion to low parts per trillion
level. The low background for these elements means that the detection of the tracer
releases should be relatively unambiguous.
Exhibit No. 69
Case No. IPC-03-
J. Prescott, IPCo
Page 8 of 10
Recently all the field sites were sampled during a second field expedition which was
completed on the 3/11/04. These samples are yet to be analyzed, but will give a much
clearer picture of the effectiveness of the IPCo operational seeding program.
Possible
Generator
Source
KR,A*
MM, KR, BM
NGV, A*
, KR, BM
NGV, A*
MM, KR, BM
NGV, A*
, KR, BM
NGV, A *
12/12/03 -12/15/03 T2 BM, BC, NGV, A*
Generator Codes: A * = Aircraft, M = Banner Mine, BC = Boise Cascade, KR =Kempner Ranch,
MM = Mammoth Mine and NGV = North Garden Valley.
Event
Table 1. Silver Enrichment Events
Estimated Date of Present at Sites
Storm
01/06/04 -01/08/04
12/27/03 - 1/01/04
, T4
, T4, MZ
12/27/03 - 1/01/04
12/23/03 - 12/26/04 , T4
12/23/03 - 12/26/04 , T4
Snow Data for MZ Sampling Site
10
-:.. _
~_n
___
+n__n ~ --- MZ SWE vs MZ Snow Depth
, ---
Storm Periods 1-L- 20 -, __n_t_nn_~n__tn____n -jt-____nII
~ -+--~---- -+------~-----+----
----i+-------1-E --1----1------I I 40 -
~--~------~- ------~-----+------~+-------
II II -I---
~-- - ---+----- --~----- + ------- -
4+---
----
II
'--
T-------r---
----
I I L__L-
_____
L__-
- ____
L- --L__-
----_
J~-
-----
II II
70 ~1~~t~-~~~~~t~====::~~~~~~~T ------4+-
------
II 80 -t--
-----+------~-----+------ -~+-------
J__J_-----_L_-
----_
-L_
____
L____---- -~--4---
----~------
--~-----4-
-------~
90 --I---
~-----
-I----
-----~-----
-I----
-----
-I--I-- --
---
1:2: 3 1 1 6
:~
g. 50
(/')
100
SWE (in)
Figure 4 Estimates of storm periods in the MZ snow pack
Exhibit No. 69
Case No, IPC-03-
J. Prescott, I PCo
Page 9 of 10
References
ChID, S. K., W. G. Finnegan and R. L. Pitter, 1993: An interpretation ofthe mechanisms
of ice-crystal formation operative in the Lake Almanor cloud-seeding program. J.
AppL Meteor., 32, 1726-1732.
McGurty, B. M., 1999: Turning silver into gold: Measuring the benefits of cloud seeding.
Hydro-Review
Super, A. B. and A. W. Huggins, 1992: Investigations of the targeting of ground-released
silver iodide in Utah - Part 1: Ground observations of silver-in-snow and ice nuclei.
J. Weather Mod., 19-33.
Warburton, J. A., R. H. Stone and B. L. Marler, 1995a: How the transport and dispersion
of AgI aerosols may affect detectability of seeding effects by statistical methods.
J. Appl. Meteor., 1929-1941.
Warburton, J. A., L. G. Young and R. H. Stone, 1995b: Assessment of seeding effects in
snowpack augmentation programs: Ice nucleation and scavenging of seeding
aerosols. J. Appl. Meteor., 121-130.
Warburton, J. A., S. K. Chai and L. G. Young, 1996a: A new method of assessing
snowfall enhancement with silver iodide seeding using physical and chemical
techniques. J. Appl. Meteor., 1569-1573.
Warburton, J. A., S. K. ChID, R. H. Stone and L. G. Young, 1996b: The assessment of
snowpack enhancement by silver iodide cloud-seeding using the physics and
chemistry ofthe snowfall. J. Weather Mod., 19-28.
Exhibit No. 69
Case No. IPC-03-
J. Prescott, IPCo
Page 10 of 10