TM 5-858-7
CHAPTER 5
UTILITIES
AND
SERVICES
monitoring sensors will be installed in the trunk
51. Introduction. The numbers, kinds, and rela-
drains so that flow rates can be read at any time
tive importance of the utilities and services re-
and continuously recorded. Wet rock at cavity sur-
quired for hardened facilities vary with the prime
faces should be grouted to a depth of at least one
mission assignment, manning requirements, and
cavity radius from the opening, or to the depth re-
length of specified endurance period. However, the
quired to eliminate seepage at the rock surface,
only design considerations appreciably different
whichever is greater.
from normal standards stem from the problems of
maintaining postattack personnel isolated from am-
e. Reservoir capacity. For conservative design,
bient atmosphere and external support. Control of
assume the total discharge drains into the under-
groundwater, prevention of fire, and details of per-
ground reservoir during the postattack endurance
sonnel services are delineated in this chapter.
period. The combined discharge of the under-
ground drainage and overburden dewatering sys-
5-2. Groundwater control.
tems will be monitored during construction on a
a. Gravity drainage. For hardened underground
year-round basis, with particular attention paid to
facilities under postattack conditions, gravity
seasonal variations. The final estimate of total
drainage of seepage water into a reservoir is the
volume required for the postattack drainage reser-
only viable concept. The problem will be com-
voir will be based on three values:
pounded by weapon-induced ground shock increas-
-- M a x i m u m flow rates during the season
ing water permeability in the surrounding media.
producing greatest water volume
Successful gravity drainage depends on overbur-
--Total volume of discharge from surface, facili-
den dewatering, wet-rock drainage, and under-
ty, and buried drainage
ground reservoir capacity, all of which are site
--Maximum volume of hygienic water required
dependent.
for personnel use during postattack
b. Site selection. Review of long-term climato-
53. Fire protection.
logical data and detailed investigation of ground-
water sources, flow paths, and flow volumes should
a. Fire prevention in hardened facilities has
be part of all hardened facility site-selection stud-
more than normal importance because of closed
ies. Assessment of the severity of groundwater
ventilation systems or very limited provision for
problems will strongly influence site selection.
obtaining outside air to dilute smoke or fumes.
Construction materials and furnishings should ex-
c. Overburden dewatering. As early as possible
clude pyrotechnic metals and other combustibles.
during construction of any buried facility, the sur-
Operating procedures and regulations should mini-
face drainage should be reworked to minimize local
mize storage and handling of paper and other com-
surface-water infiltration. Overburden that con-
bustibles. Waste paper should be collected fre-
tains aquifers above a buried facility should be sur-
quently, compacted, and baled. Smoking should be
rounded by grout curtains and dewatered. Where
prohibited or confined to specific safe areas.
heavily flowing aquifers are cut off, reroute the in-
terrupted flow at the upstream face of the grout to
b. The outer shells of hardened facilities usually
prevent elevation of the water table. Specify per-
will be reinforced concrete, but the operating areas
manent installation of water-table logging wells,
usually will be housed in shock-isolated inner struc-
dewatering wells, and a pumping system adequate
tures of steel, often more than one story high. Con-
to eliminate free groundwater down to the level of
formance to National Fire Code NFPA 220, 4-hour
impervious rock within the site area.
classification shall be adhered to except as modified
herein. Floor areas should be subdivided in units
d. Wet-rock drainage. During construction, all
2
preferably not larger than 2500 ft , with floor-to-
rock in the vicinity of permanent underground cav-
ceiling walls having not less than two-hour fire-
ities must be investigated for water sources by
resistive rating. All openings, included ventilation
drilling from the cavities before permanent liners
ducts, through fire-rated floors and walls are to be
are installed. Wet-rock areas will be mapped and
provided with self-closing fire-door or fire-damper
permanent drain piping installed. Within five cavi-
assemblies. Stair and elevator shafts will be en-
ty diameters of cavity surfaces increase the num-
closed with three-hour walls and fire-door assem-
ber of drain holes until the total drainage rate
blies. Except for blast-resistant doors, fire-door
becomes constant or declines. Permanent flow-
5-1
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