Natural resources conservation service\
conservation practice sPECIFICATION

well\
material specification

introduction

The materials covered by this specification are as referred to by
Conservation Practice **Standard** and Conservation Practice
**Specification** 642- Well.

Casing

Casing materials may be pipe made of steel, cooper, plastic, fiberglass,
asbestos-cement, concrete, or other similar materials of equivalent
strength and durability.

Steel pipe, copper, asbestos-cement pipe, reinforced plastic mortar,
plastic or fiberglass pipe may be used for well casings in drilled
wells. Only steel pipe shall be used for driven wells.

Steel

Steel well casings shall equal or exceed the requirements specified in
ASTM-A-589. Steel pipe manufactured for other purposes can be used if
the quality of the pipe equals or exceeds that specified in ASTM-A-589.

Used steel pipe may be used for well casing provided that it is of good
quality and has a wall thickness equal to greater than Schedule 40, and
greater than the thickness shown in Table 5 of the standard.

Plastic

If the water will be used for human consumption, plastic casings for
transporting portable water must be approved by NSF. Plastic casings
shall be made of acrylonitrile­butadiene-styrene (ABS), polyvinyl
chloride (PUC), or styrene-rubber (SR) and shall conform to the
requirements specified in ASTM-F-480. Plastic pipe manufactured for
water or irrigation pipelines can be used if the quality of the pipe
equal or exceeds that specified in ASTM-F-480.

Acrolonitrile-butadiene-sty­rene  (ABS)

ABS casing pipe material shall meet or exceed the requirements of ASTM
Specification\
D-4673, cell classification 434 or 533. ABS well casing pipe, couplings
and screen plastics shall be virgin plastic produced by the original
com­pounder without extenders. It shall contain polymers, blends or
polymers, or both in which the minimum butadiene content is 6 percent;
the minimum acrylonitrile content is 15 percent, the minimum styrene or
substituted styrene content, or both, is 15 percent; the maximum content
of other monomers is 5 percent; and lubricants, stabilizers, and
colorants.

Polyvinyl-chloride (PVC)

PVC casing pipe material shall meet or exceed the requirements of ASTM
Specifi­cation D-1784, a cell classification 12454-A,-B,-C or
14222-A,-B,-C,-D. PVC casing pipe, couplings and screen plastics shall
be made of virgin plastic produced by the original compounder without
extenders. It shall contain polyvinyl chloride homopolymer, and such
additives\--stabilizers, lubricants, processing aids, impact improvers
and colorants\--as needed to provide the required processing and
toughness characteristics.

Styrene-rubber (SR)

SR casing pipe material shall meet or exceed the requirements of ASTM
Specifi­cation D-1892, cell classification 4434-A. SR well casing pipe,
couplings and screen plastics shall be made of virgin plastic produced
by the original compounder with materials such as antioxidants and
lubricants. It may contain as much as 15 percent acrylon­itrile, combined
in the styrene plas­tics, rubbers, or both. The rubbers shall be of
polybutadiene, butadiene styrene type, or both, with a maximum stryrene
content of 25 percent or nitrile type, or both. The combined styrene
plastic and rubber content shall not be less than 90 percent.

Concrete

Concrete well casings shall be rein­forced and shall meet or exceed the
requirements of ASTM-C-76. The minimum 28-day compressive strength shall
be 4,000 lbs./in.

Fiberglass

Fiberglass casings can be used if tests indicate that:

1\. The material meet the requirements specified in ASTM-D-2996, tests
for long-term cyclic pressure strength, long-term static pressure
strength, and short-term rupture strength as required in ASTM-D-2996 are
not needed because the pipes are to be used for well casings.

2\. The points meet the requirements specified in Section 3.8,
ASTM-F-480.

3\. The modulus of elasticity is certified for use in determining
maximum depth.

Reinforced Plastic MortAr

Reinforced plastic mortar casings should equal or exceed the
require­ments speci­fied in ASTM-D-3517.

Table 1 - Maximum depth of installation for plastic (SDR-PR) pipe

  --------------------------------------------------------------------------
  SDR            Material                                     
  -------------- -------------- -------------- -------------- --------------
                 PVC                           ABS            SR

                 Modulus of                                   
                 elasticity (E)                               

                 400,000        320,000        250,000        300,000

  13.5           985            785            615            735

  17             475            380            295            355

  21             245            200            150            185

  26             130            100            80             95

  32.5           65             50             40             50
  --------------------------------------------------------------------------

Table 2 - Dimension and maximum depth of installation for Schedules 40
and 80 PVC plastic pipe

+--------+--------+--------+--------+--------+--------+--------+--------+
| Nom.   | Out    | Sc     |        |        | Sc     |        |        |
|        |        | hedule |        |        | hedule |        |        |
| dia.   | dia.   | 40     |        |        | 80     |        |        |
|        |        |        |        |        |        |        |        |
| in.    | in.    |        |        |        |        |        |        |
+--------+--------+--------+--------+--------+--------+--------+--------+
|        |        | Min.   | SDR    | Max.   | Min.   | SDR    | Max.   |
|        |        |        |        |        |        |        | depth  |
|        |        | wall   |        | depth  | wall   |        |        |
|        |        |        |        |        |        |        | ft.    |
|        |        | in.    |        | ft.    | in.    |        |        |
+--------+--------+--------+--------+--------+--------+--------+--------+
| 2      | 2.375  | 0.154  | 15.4   | 650    | 0.218  | 10.9   | 1,.960 |
+--------+--------+--------+--------+--------+--------+--------+--------+
| 2.5    | 2.875  | 0.203  | 14.2   | 840    | 0.275  | 10.4   | 2,260  |
+--------+--------+--------+--------+--------+--------+--------+--------+
| 3      | 3.500  | 0.216  | 16.2   | 550    | 0.30   | 11.7   | 1,550  |
+--------+--------+--------+--------+--------+--------+--------+--------+
| 3.5    | 4.00   | 0.226  | 17.7   | 420    | 0.318  | 12.6   | 1,220  |
+--------+--------+--------+--------+--------+--------+--------+--------+
| 4      | 4.50   | 0.237  | 19.0   | 340    | 0.337  | 13.4   | 1,010  |
+--------+--------+--------+--------+--------+--------+--------+--------+
| 5      | 5.563  | 0.258  | 21.6   | 230    | 0.375  | 14.8   | 740    |
+--------+--------+--------+--------+--------+--------+--------+--------+
| 6      | 6.625  | 0.280  | 23.7   | 170    | 0.432  | 15.3   | 660    |
+--------+--------+--------+--------+--------+--------+--------+--------+
| 8      | 8.625  | 0.322  | 26.8   | 120    | 0.50   | 17.3   | 450    |
+--------+--------+--------+--------+--------+--------+--------+--------+
| 10     | 10.75  | 0.365  | 29.5   | 90     | 0.593  | 18.1   | 390    |
+--------+--------+--------+--------+--------+--------+--------+--------+
| 12     | 12.75  | 0.406  | 31.4   | 70     | 0.687  | 18.6   | 360    |
+--------+--------+--------+--------+--------+--------+--------+--------+

Note: Table is for PVC Schedule pipe made of material having a modulus
of elasticity of 400,000 lb/in^2^.\
For PVC pipe having a modulus of elasticity of 360,000, multiply the
depth by a factor of 0.9.\
For PVC pipe having a modulus of elasticity of 320,000, multiply the
depth by a factor of 0.8.\
A factor of 0.625 can be used for ABS Schedules 40 and 80 pipe having a
modulus of elasticity of 250,000\
lbs/in^2^.

Table 3 - Dimensions and depth limitations for reinforced plastic mortar
well casings.

<table style="width:100%;">
<colgroup>
<col style="width: 10%" />
<col style="width: 10%" />
<col style="width: 10%" />
<col style="width: 10%" />
<col style="width: 10%" />
<col style="width: 10%" />
<col style="width: 10%" />
<col style="width: 10%" />
<col style="width: 10%" />
<col style="width: 10%" />
</colgroup>
<tbody>
<tr class="odd">
<td rowspan="3"><p>Dia</p>
<p>(in)</p></td>
<td colspan="9">Maximum depth (ft)</td>
</tr>
<tr class="even">
<td>20</td>
<td>60</td>
<td>100</td>
<td>200</td>
<td>300</td>
<td>400</td>
<td>500</td>
<td>750</td>
<td>1,000</td>
</tr>
<tr class="odd">
<td colspan="9">Minimum wall thickness (in.)</td>
</tr>
<tr class="even">
<td>8</td>
<td>0.17</td>
<td>0.17</td>
<td>0.23</td>
<td>0.23</td>
<td>0.23</td>
<td>0.29</td>
<td>0.29</td>
<td>0.33</td>
<td>0.33</td>
</tr>
<tr class="odd">
<td>10</td>
<td>.17</td>
<td>.17</td>
<td>.28</td>
<td>28</td>
<td>.28</td>
<td>.36</td>
<td>.37</td>
<td>.41</td>
<td>.41</td>
</tr>
<tr class="even">
<td>12</td>
<td>.18</td>
<td>.19</td>
<td>.34</td>
<td>.34</td>
<td>.34</td>
<td>.43</td>
<td>.43</td>
<td>.46</td>
<td>.46</td>
</tr>
<tr class="odd">
<td>14</td>
<td>.19</td>
<td>.22</td>
<td>.32</td>
<td>.40</td>
<td>.40</td>
<td>.43</td>
<td>.46</td>
<td>.46</td>
<td>.46</td>
</tr>
<tr class="even">
<td>15</td>
<td>.19</td>
<td>.24</td>
<td>.34</td>
<td>.34</td>
<td>.46</td>
<td>.46</td>
<td>.46</td>
<td>.46</td>
<td>.46</td>
</tr>
<tr class="odd">
<td>16</td>
<td>.20</td>
<td>.25</td>
<td>.36</td>
<td>.36</td>
<td>.46</td>
<td>.46</td>
<td>.46</td>
<td>.46</td>
<td>.46</td>
</tr>
<tr class="even">
<td>18</td>
<td>.21</td>
<td>.28</td>
<td>.40</td>
<td>40</td>
<td>45</td>
<td>.45</td>
<td>.45</td>
<td>.52</td>
<td>.42</td>
</tr>
<tr class="odd">
<td>20</td>
<td>.21</td>
<td>.31</td>
<td>.42</td>
<td>.42</td>
<td>.45</td>
<td>.45</td>
<td>.45</td>
<td>.54</td>
<td>.54</td>
</tr>
<tr class="even">
<td>21</td>
<td>.21</td>
<td>.33</td>
<td>.48</td>
<td>.48</td>
<td>.48</td>
<td>.48</td>
<td>.48</td>
<td>.57</td>
<td>.57</td>
</tr>
<tr class="odd">
<td>24</td>
<td>.24</td>
<td>.38</td>
<td>.48</td>
<td>.48</td>
<td>.57</td>
<td>.57</td>
<td>57</td>
<td>.57</td>
<td>.57</td>
</tr>
<tr class="even">
<td>27</td>
<td>.26</td>
<td>.40</td>
<td>.49</td>
<td>.49</td>
<td>.49</td>
<td>.62</td>
<td>.62</td>
<td>.62</td>
<td>.62</td>
</tr>
<tr class="odd">
<td>30</td>
<td>.29</td>
<td>.44</td>
<td>.49</td>
<td>.49</td>
<td>.49</td>
<td>.68</td>
<td>.68</td>
<td>.68</td>
<td>.68</td>
</tr>
<tr class="even">
<td>33</td>
<td>.32</td>
<td>.44</td>
<td>.60</td>
<td>.60</td>
<td>.60</td>
<td>.75</td>
<td>.75</td>
<td>.75</td>
<td>.75</td>
</tr>
<tr class="odd">
<td>36</td>
<td>.35</td>
<td>.48</td>
<td>.65</td>
<td>.65</td>
<td>.65</td>
<td>.82</td>
<td>.82</td>
<td>.82</td>
<td>.82</td>
</tr>
</tbody>
</table>

Table 4 - Minimum thickness of metal casings for wells

+---------------------+---------------------+--------------------------+
| Dia.                | Minimum wall        |                          |
|                     | thickness (in.)     |                          |
| in                  |                     |                          |
+---------------------+---------------------+--------------------------+
|                     | Steel               | lightweight              |
|                     |                     |                          |
|                     | casing              | galv.casing              |
+---------------------+---------------------+--------------------------+
| 1.0                 | 0.133               | \--                      |
+---------------------+---------------------+--------------------------+
| 1.5                 | .145                | \--                      |
+---------------------+---------------------+--------------------------+
| 2.0                 | .154                | \--                      |
+---------------------+---------------------+--------------------------+
| 2.5                 | .203                | \--                      |
+---------------------+---------------------+--------------------------+
| 3.0                 | .216                | \--                      |
+---------------------+---------------------+--------------------------+
| 3.5                 | .226                | \--                      |
+---------------------+---------------------+--------------------------+
| 4.0                 | .060                | 0.0322                   |
+---------------------+---------------------+--------------------------+
| 4.5                 | .060                | .0322                    |
+---------------------+---------------------+--------------------------+
| 5.0                 | .075                | .0382                    |
+---------------------+---------------------+--------------------------+
| 6.0                 | .105                | .0382                    |
+---------------------+---------------------+--------------------------+
| 8.0                 | .105                | .0486                    |
+---------------------+---------------------+--------------------------+
| 10.0                | .105                | .0486                    |
+---------------------+---------------------+--------------------------+

Lightweight galvanized casings shall be used only in areas where local
experience has proved them to be satisfactory.\
Diameters 1\" to 3.5\" are for driven or drilled wells.

Table 5 - Maximum depth of installation for steel casings (ft.)

<table>
<colgroup>
<col style="width: 16%" />
<col style="width: 8%" />
<col style="width: 8%" />
<col style="width: 8%" />
<col style="width: 8%" />
<col style="width: 8%" />
<col style="width: 8%" />
<col style="width: 8%" />
<col style="width: 8%" />
<col style="width: 8%" />
<col style="width: 8%" />
</colgroup>
<tbody>
<tr class="odd">
<td rowspan="5"><p>Wall</p>
<p>Uncoated</p>
<p>Thickness</p>
<p>(in.)</p></td>
<td colspan="10" rowspan="2">Casing size (in.)</td>
</tr>
<tr class="even">
</tr>
<tr class="odd">
<td>4</td>
<td>5</td>
<td>6</td>
<td>8</td>
<td>10</td>
<td>12</td>
<td>14</td>
<td>16</td>
<td>18</td>
<td>24</td>
</tr>
<tr class="even">
<td colspan="10">Outside diameter (in.)</td>
</tr>
<tr class="odd">
<td>4.5</td>
<td>5.563</td>
<td>6.625</td>
<td>8.625</td>
<td>10.75</td>
<td>12.75</td>
<td>14.0</td>
<td>16.0</td>
<td>18.0</td>
<td>24.0</td>
</tr>
<tr class="even">
<td>0.036</td>
<td>80</td>
<td>40</td>
<td>25</td>
<td>-</td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
</tr>
<tr class="odd">
<td>0.048</td>
<td></td>
<td>180</td>
<td>100</td>
<td>50</td>
<td>25</td>
<td></td>
<td></td>
<td></td>
<td></td>
<td></td>
</tr>
<tr class="even">
<td>0.060</td>
<td></td>
<td>370</td>
<td>190</td>
<td>110</td>
<td>50</td>
<td>25</td>
<td>--</td>
<td></td>
<td></td>
<td></td>
</tr>
<tr class="odd">
<td>0.075</td>
<td></td>
<td>720</td>
<td>380</td>
<td>220</td>
<td>100</td>
<td>50</td>
<td>30</td>
<td>20</td>
<td>--</td>
<td></td>
</tr>
<tr class="even">
<td>0.105</td>
<td></td>
<td>2030</td>
<td>1060</td>
<td>620</td>
<td>280</td>
<td>140</td>
<td>80</td>
<td>60</td>
<td>40</td>
<td>--</td>
</tr>
<tr class="odd">
<td>0.135</td>
<td>--</td>
<td>--</td>
<td>1340</td>
<td>600</td>
<td>310</td>
<td>180</td>
<td>130</td>
<td>90</td>
<td>60</td>
<td></td>
</tr>
<tr class="even">
<td>0.164</td>
<td>--</td>
<td>--</td>
<td>--</td>
<td>1080</td>
<td>550</td>
<td>330</td>
<td>250</td>
<td>160</td>
<td>110</td>
<td>--</td>
</tr>
<tr class="odd">
<td>0.179</td>
<td>--</td>
<td>--</td>
<td>--</td>
<td>1410</td>
<td>720</td>
<td>430</td>
<td>320</td>
<td>210</td>
<td>150</td>
<td>-</td>
</tr>
<tr class="even">
<td>0.188</td>
<td>--</td>
<td>--</td>
<td>--</td>
<td>1650</td>
<td>840</td>
<td>500</td>
<td>370</td>
<td>250</td>
<td>170</td>
<td>70</td>
</tr>
<tr class="odd">
<td>0.219</td>
<td>--</td>
<td>--</td>
<td>--</td>
<td>--</td>
<td>1340</td>
<td>800</td>
<td>600</td>
<td>400</td>
<td>280</td>
<td>110</td>
</tr>
<tr class="even">
<td>0.250</td>
<td>--</td>
<td>--</td>
<td>--</td>
<td>--</td>
<td>--</td>
<td>1190</td>
<td>890</td>
<td>600</td>
<td>420</td>
<td>170</td>
</tr>
<tr class="odd">
<td>0.281</td>
<td>--</td>
<td>--</td>
<td>--</td>
<td>--</td>
<td>--</td>
<td>--</td>
<td>1280</td>
<td>850</td>
<td>590</td>
<td>250</td>
</tr>
<tr class="even">
<td>0.312</td>
<td>--</td>
<td>--</td>
<td>---</td>
<td>--</td>
<td>--</td>
<td>--</td>
<td>--</td>
<td>1170</td>
<td>820</td>
<td>340</td>
</tr>
<tr class="odd">
<td>0.344</td>
<td>--</td>
<td>--</td>
<td>--</td>
<td>--</td>
<td>--</td>
<td>--</td>
<td>--</td>
<td>--</td>
<td>1100</td>
<td>460</td>
</tr>
<tr class="even">
<td>0.375</td>
<td>--</td>
<td>-</td>
<td>--</td>
<td>--</td>
<td>--</td>
<td>--</td>
<td>---</td>
<td>--</td>
<td>--</td>
<td>600</td>
</tr>
<tr class="odd">
<td>0.438</td>
<td>-</td>
<td>-</td>
<td>--</td>
<td>--</td>
<td>--</td>
<td>--</td>
<td>--</td>
<td>--</td>
<td>--</td>
<td>960</td>
</tr>
</tbody>
</table>

Note: Based on the Cleindeinst Equation for Critical Collapse Pressure,
using Poisson\'s ratio (u) of 0.30 and a modulus of elasticity (E) of
30,000,000 lbs/in^2^.\
D= [2E]{.underline} x [2.31\
]{.underline} 1-u^2^ SDR (SDR-1)^2^