Fresh Water forMcMurdo StationRICHARD D. WHITMER1

Lieutenant, CEC, USNStaff, Commander, Naval Construction Battalions,

U.S. Atlantic Fleet

Obtaining water has always been a problem formen in Antarctica. The traditional method—meltingsnow—consumes fuel that must be imported atgreat expense and assumes the availability of un-contaminated snow. The growth of McMurdo Sta-tion has brought both an increasing demand forwater (and hence for fuel) and an increasing con-tamination problem. Vehicles have had to travelfarther and farther from the station to get pure snowfor the snow melters, consuming in the process stillmore fuel. The Navy's answer was to desalinate sea-water, preferably by using nuclear power.

During Operations Deep Freeze 63 and 64, a wa-ter-distillation plant and the beginning of a distri-bution system were installed by the Seabees. Thedistillation plant basically consists of a flash-distil-lation unit with a daily production capacity of14,400 gallons, two 55,000-gallon bolted-steel stor-age tanks (one for fresh water and one for saltwater), and an oil-fired boiler; these were installedin a heated Robertson building erected in the PM-3A nuclear power plant complex, on the side ofObservation Hill. Also installed were pipelines tocarry seawater to the distillation plant and to returnconcentrated brine to McMurdo Sound.

Intake SystemA variety of intake systems were installed and

tested in an effort to find one that would work year-round with a minimum of maintenance. An off-shore raft, tried during Deep Freeze 65, workedwell for a while, but icebergs destroyed it during astorm (Fig. 1). During Deep Freeze 66, a heatedhose was installed. It proved successful in two outof three situations: when the annual ice was com-pletely out, the hose was simply placed in the waterat the shoreline; when the ice was solidly formed, thehose was run across the ice to a small, heatedshack that prevented a hole in the ice from re-freezing. The problem was the period in between,when the ice was still present but was too rottento be trustworthy. Under those conditions, use ofthe heated hose was a tricky operation involvingconstant surveillance and frequent changes of loca-

Formerly Officer-in-Charge. NCBU 201.

(U.S. Nai y Photo)Figure 1. Rafts for saltwater intake were damaged by

rough seas.

tion. Since this situation exists for nearly half theaustral summer, U.S. Naval Construction BattalionUnit (NCBU) 201 designed another system in an at-tempt to solve the problem permanently.

The permanent intake system was constructedduring Deep Freeze 67. The main component is ajetty—built of 15,000 cubic yards of native fill—that extends 110 feet into McMurdo Sound (Fig.2). For ease of maintenance access, the top surfaceis 20 feet wide. Before the tip of the jetty was built,a 1-shaped intake pipe (made of welded sections of36-inch-diameter culvert pipe) was set in place 100feet from the pump house. 2 The two inlets to theI are 20 feet below the jetty surface—well under thefreeze line—and a small shack was built above theintake pipe. Warm air from an electrical heater (orfrom a standby oil-burning unit that is used when thePM-3A reactor is shut down) is blown into theculvert opening to keep it ice-free. A length of

(U.S. \w y Photo)

Figure 2. Pump house, heated pipe, and intake house onnew jetty.

A ntarctic Journal, vol. 11, no. 4., p. 138.

September-October, 1967 213

heated hose, suspended in the culvert opening, isconnected to the pump house at the foot of thejetty with heated copper pipe set on wooden crib-bing. (The pump house is a small, heated Robertsonbuilding, erected during Deep Freeze 64, thathouses two 150-gallon-per-minute pumps.)

Operationally, the new system proved highly suc-cessful, but a storm in early March drove heavyswells over the jetty, washing away sections of thepipe and cribbing and damaging the intake house(Fig. 3). The jetty and culvert, however, remainedintact and were repaired by the wintering-overparty. Although the exposed pipe and intake housewill require additional protection from severe waveaction, the present intake system is basically ofsound design.Distillation Plant

From the pump house, seawater is lifted nearly300 feet to a 55,000-gallon storage tank at thewater-distillation plant. The flow to the tank is con-tinuous while the distillation unit is operating. (Afloat switch automatically stops the pump when thetank is filled.) Seawater from the storage tank goesthrough the Aqua-Chem distillation unit (Fig. 4),which produces approximately 1 gallon of freshwater from 10 gallons of salt water.

The Aqua-Chem distillation unit is a multistageflash evaporator. Seawater that has been preheatedto 170°F. is successively passed through 16 stages.In each stage, it is subjected to a high vacuum,causing flash vaporization of a portion of the water.

L'i I'IitiIo)

Figure 3. Storm-whipped waters battering pipe and intakehouse in March 1967.

U .S. Nail , Photo)

Figure 4. Distillation unit being placed in building.

.(U.S. Nal .l Photo )

Figure 5. Intake line (left), supply and return lines betweenpump house and plant, and brine discharge pipe (rig/it).

(The vacuum is steadily increased to compensate forthe heat lost during evaporation in the precedingstage.) The vapor is condensed on baffles and thecondensate, which has a salinity of approximatelyone part per million, is drawn off as fresh waterat approximately 70°F. The concentrated brine is re-turned down the hill to a point near the pump house(Fig. 5).

A system of piping crossovers allows the distilla-tion unit to be powered with steam from either thePM-3A or a standby oil-fired boiler. The boilerinstalled during Deep Freeze 64 for test purposeswas replaced the following season by a Cleaver-Brooks boiler which produces enough steam to ac-commodate two distillation units as well as thatneeded to heat the water-distillation building. Tocompletely preclude the possibility of radioactive con-

The boiler's steam output is actually sufficient to heatthe entire PM-3A complex, but such use is not presentlycontemplated.

214 ANTARCTIC JOURNAL

'I.

tamination, a separate reboiler was installed duringDeep Freeze 66 (and the following winter) to pro-vide "nuclear steam" to the distillation plant: thesteam indirectly produced by the superheated waterfrom the reactor is passed through the reboiler toproduce the steam that boils the seawater in thewater-distillation unit (Fig. 6). Thus there are threeclosed loops involved in transferring energy fromthe reactor core to the distillation unit, and allof them would have to leak simultaneously to causecontamination of the fresh water produced.

The distillation plant has worked quite well. Infact, the most significant problem encountered in itsoperation was caused by failures in the distributionsystem. When shut down because of such a failure,the distillation unit dries out, making the task of re-turning it to operational status extremely difficult.

(J'iioto: S. J. V, laze!:)

Figure 7. Electrical heating tape keeps flanged pipes fromfreezing.

4I5F—II355F—II 70Fk—FRESH WATER

Figure 6. Schematic representa-tion of energy-transfer process.Before entering liFilt (rig/it), sea-water is heated slight/v ii'he,iused to condense vapor (111(1

t/ieii is brought to I70 F. withsteam previously used in air-

ejector to create vacuum.(NNPU Drawing)

REBOILER DISTILLATIONUNIT

_I 701FFJ

- II I[—SEAWATER

SECONDARY LOOP REBOILER LOOPEVAPORATOR LOOP(CLOSED) (CLOSED) (OPEN)

V'O

For that reason, trucking water to the station whenthe distribution system fails is an advantage to boththe plant's operators and the consumers of the water.

Distribution System

As originally installed, the freshwater distributionsystem consisted of Ric-Wil heated pipe. The sys-tem failed early in its operation and was rebuilt dur-ing Deep Freeze 66, at which time its layout wasalso altered significantly to correspond to the long-term plan for station development, and constructionof a sanitary sewer system was started. (Additionalwork on both the distribution and the sewage sys-tems during Deep Freeze 67 has made flush toilets areality at McMurdo.)

Fresh water, salt water, effluent brine, and sew-age are now transported through flanged copperpipe that is elevated above the ground on timbercribbing. Electro-Wrap tape was placed along thepipe (Fig. 7) before it was covered with insulationand encased in either steel or aluminum (Fig. 8).The heat tape, which operates at 88 volts and israted at 24 watts per foot, is regulated by thermo-stats that control 100-foot sections of the systems.The thermostats, associated transformers, and cir-cuit breakers are housed in galvanized steel cabinets.

-- •' -

-L_-kW KH

Figure 8. Pipe is covered with insulation and jacketed inmetal.

The present safeguards against freezing are con-sidered satisfactory, but other problems—principallyexcessive water pressure—still create operationaldifficulties. Because the distillation plant is some300 feet above the main part of the station, con-siderable pressure is created within the lower por-tion of the distribution system. During Deep Freeze67, NCBU 201 installed a pressure-reducing stationto control the line pressure in the distribution sys-tem; the variety of building elevations being served,

September-October, 1967 215

however, makes the settings at the station critical.During the same season, an accumulator was in-stalled at the pressure-reducing station in a furthereffort to eliminate water hammer, which causesminor leaks and, by damaging the heat tape, leadsto isolated freezing in the system.4

Production per PersonWhile a great improvement, the new water-

production system will not make water abundantat McMurdo Station. At maximum daily capacity, itcan provide 72 gallons of water for each of 200people—which is roughly the population this winter.In summer, when the average population increasesto over 700, the daily ration amounts to less than20 gallons per person. The installation of a seconddistillation unit, planned for the near future, willhelp to assure continuous operation and will in-crease the daily production capability. Combinedwith increased experience in operating the presentfacility, this should assure McMurdo Station of acontinuous and—for the Antarctic—relatively plen-tiful supply of good, fresh water.

Second Winter Flight Successful

An LC-130 Hercules made the second scheduledwinter flight to Antarctica on September 2 to bringtwo scientists and a Navy officer, as well as mail andprovisions, to McMurdo Station. The two scientists,Dr. Robert E. Benoit and Mr. Ruff Lowman, both ofVirginia Polytechnic Institute, will conduct studies ofmicroorganisms in the volcanic soils of Taylor Valleyin the Royal Society Range. The Navy officer wasCaptain H. A. Kelley, the commanding officer ofAntarctic Support Activities, Davisville, RhodeIsland, who made a brief inspection of the station.

Returning aboard the aircraft were Captain Kelley,a scientific party of three men headed by Dr. JacquesS. Zaneveld of Old Dominion College, Norfolk, Vir-ginia, and two injured members of VX-6: Lt. BrianH. Shoemaker and AZ2 Joseph Musser.

The first scheduled winter flight to Antarcticatook place on June 18, 1967 (cf. Antarctic Journal,vol. II, no. 3, p. 81, and no. 4, p. 153).

Water hammer (the concussion produced in an airtightwater vessel upon a sudden stoppage or start of flow) wasa problem in the intake pipes, too, and a series of ac-cumulators was installed in the saltwater pump house.

General engineering practice in the United States is toprovide 150 gallons of water per person per day.

The Use ofWeather Satellites

in AntarcticaRALPH W. SALLEE

Lieutenant Commander, USNU.S. Naval Support Force, Antarctica

In 1965, Operation Deep Freeze was furnishedtwo Fairchild-Stratos Automatic Picture Transmis-sion (APT) receivers. These early-model receiv-ers were installed at opposite ends of the 2,500-mile track followed by Deep Freeze aircraft andships between New Zealand and Antarctica—oneat the Naval Support Force's advance headquartersin Christchurch, New Zealand, and the other at Mc-Murdo Station, Antarctica (Fig. 1).

These two ground stations were of little use duringthe remainder of the Deep Freeze 66 season andthe subsequent austral winter. Not until DeepFreeze 67, when the extremely successful ESSAII and IV and Nimbus II satellites were in orbit,was full and productive utilization of the stationsachieved. During the 1966 austral winter, NewZealand meteorologists placed the Christchurchground station in operation and maintained ituntil they were relieved in September by Navy per-sonnel. As sunlight returned to Antarctica, theequipment at McMurdo Station also became opera-tional. Since the operation of the APT station at

(U.S. Navy Photo)Figure 1. APT antenna at McMurdo Station.

216 ANTARCTIC JOURNAL