ML20080A476
| ML20080A476 | |
| Person / Time | |
|---|---|
| Site: | Limerick  |
| Issue date: | 01/21/1984 |
| From: | Hansler G DELAWARE RIVER BASIN COMMISSION |
| To: | Office of Nuclear Reactor Regulation |
| References | |
| NUDOCS 8402060080 | |
| Download: ML20080A476 (53) | |
Text
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i WEST TRENTON, N EW JERS EY 08828
**.., ,,,/ (609)883-9500 o ,, ,,.l cr e HEADQUARTERS LOCATION GERALD M.HAN5LER 25 STATE POLICE DRIVE
,! ExCEUTIVE DIREETOR WEST TRENTO N,N.J. Januan 31, 1984
Dear Sir:
We have received a copy of the letter to you from Mr. Bruce Blanchard, Director, Environmental Project Review, Office , of the Secretary, U. S. Department of the Interior (DOI), dated August 26, 1983, presenting comments on the draft environmental impact statement for the Limerick Generating Station in Montgomery County, Pennsylvania. Most of-the DOI's comments relate to the rater resources of the Delaware River Easin as they would be affected by the Limerick project, and the DOI seeks clarification on various water-resources issues. As the Delaware River Basin Commission approved the use of water resources for the Limerick project, I believe it would be helpful if we respond to the DU. comments on these issues. The enclosed DRBC staff responses to water-related comments in the DOI letter of August 26, 1983, have been prepared to help clarify some of the matters discussed in that letter. If we can help furtl.cr, please let me know. r Sincerely, I b / Gerald M. Hansler U. S. Nuclear Regulatory Commission Attention: Director of Division of Licensing Washington, D. C. 20555 Enc. 4 cc: Commissioner George J. Kanuck, Jr. (w/ enc.) 8402060080 840121
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.DRBC Staff Responses to Comments from
, U.S. Department of the Interior on Draft Environmental Impact Statement on the Limerick Generating Station
; Montgomery County, Pennsylvania January 1984 Introduction
~ In June 1983, the U.S. Nuclear Regulatory Commission (NRC) issued a Dratt Environmental Statement (DES) related to the operation of the Limerick Electric Generating Station, Units 1 and 2, currently under construction on the Schuylkill River in Montgomery County, Pennsylvania. By letter of August 26, 1983, the U.S. Department of the Interior (DOI) transmitted comments on the DES to the NRC, and a copy of the DOI letter was received by the Delaware River Basin Comnission (DRBC), the agency that manages the water resources of the Delaware River Basin pursuant to the Delaware River Basin Compact (Public Law 87-328, Approved September 27, 1961, 75 Statutes at Large 688). The DRBC had earlier approved the use of water for the Limerick Station from the Schuylkill River, Perkiomen Creek, and the Delaware River, all with certain restrictions and limits (DRBC Docket Number D-69-210 CP--Final).
Many of the DOI comments relate to the use of water for the Limerick project, as approved by the DRBC, and include requests for clarification. Such clarification should logically come from the DRBC. For this reason, the DRBC staff has prepared responses to those DOI comments that are related to the use of water from the Schuylkill River, Perkiomen Creek, and the Delaware River, as well as those comments related to water quality in these streams, and also in the East Branch Perkiomen Creek, which is to convey Delaware River water to Perkiomen Creek. For convenient reference, the DRBC staf f responses are presented under the headings given in the DOI letter. Surface water hydrology The DOI letter objected to the statement in section 4.3.1.1.3 that upstream reservoirs are cacable of maintaining a flow of 3,000 cfs in the
0
. Delaware River at Trenton during a moderate drought. The DOI cited records showing Trenton flows less than 2,500 cfs during the recent moderato drought of 1980-81. We believe that the DOI is confusing flow-maintenance capability of existing reservoirs with actual reservoir operations during that drought, in which the DRBC, not knowing how long the drought would last, deemed it prudent to conserve water in storage by reducing the minimum flow objective at Trenton from the normal rate of 3,000 cfs to 2,500 cfs. With hindsight, we 4
know now that we could have easily maintained 3,000 cfs at Trenton during the 4 dry period of 1980 and 1981. However, water supply managers do not have the ability to foresee - the future, and they must frequently act on the basis of current facts and future risks. The fact that 3,000 cfs flows were not maintained at all times during the 1980-81 drought does not mean that the existing reservoirs system did not have that capability; it means only that the DRBC chose to conserve water against the possibility of an extended severe i drought. On June 29, 1983, the DRBC adopted reservoir operating rules that will ] automatically reduce the Trenton flow objective at Trenton whenever the combined storage in New York City's three Delaware Basin reservoirs drops to a predetermined " drought warning" or " drought" level, as set forth in Resolution l 83-13 -(appendix A). For the drought-warning condition, the Trenton flow objective will be 2,700 cfs. For drought conditions, the target flow will vary from 2,500 cfs to 2,900 cfs, depending on the season and salinity levels in the estuary, as measured by the seven-day average location of the 250-mg/l isochlor (the " salt front"). The DOI notes that during the period of record historical flows at Trenton have dropped below 2,500 cfs at least once in every calendar month of one year or another except March, April, and May with 90 percent of the existing upstream storage in operation. This 90 percent of the now existing reservoir capacity above Trenton represents the storage capacity in New York City's three upper-basin reservoirs (Pepacton, Cannonsville, and Neversink). These reservoirs are operated to meet a flow objective at Montague, N.J. , in accordance with the U.S. Supreme Court decree of 1954 in New Jersey v. New York, 347 U.S 955 (1954), and are not operated to meet any flow objective at Trenton. However, in maintaining minimum flows at Montague, the New York City
e reservoirs do augment low river flows as measured at Trenton. Nevertheless, it is not surprising that releases to meet a Montague flow objective, without additional releases from other reservoirs, do not always meet the Trenton flow objective. 1 I Beltzville Reservoir began regulating flows in February 1971, and at that time increased the flow capability at Trenton. Observed Trenton flows preceding that date should not be used to judge current (1983) flow capability at Trenton, unless these flows are a'dj usted to show the effects of current re gulation. Based on computerized mathematical models of the existing basin hydrologic system, the DREC staff has estimated that in a 1983 recurrence of the hydrology of 1965, the driest year of record, a minimum four-month (June-September) average flow of 2,470 cfs could be provided, assuming operation of the system in accordance with DRBC Resolution 83-13. Although this level of flow regulation at Trenton, together with flow regulation by Blue Marsh Reservoir in the Schuylkill River basin, will prevent violation of the recently adopted salinity standard for the estuary, it is projected that additional storage will be required by about 1987 to protect the salinity standard. The DOI notes that daily flows at Trenton dropped below 2,500 cfs during several months in 1977, 1980, and 1981. The specific dates, along with the average daily flows and the mean monthly flows, are listed in table 1. These data are taken from the annual reports on water resources data for New Jersey, published by the U.S. Geological Survey (USGS), which operates the stream-gaging station at Trenton. These data show for each of four months in 1977 one day on which the flow averaged less than 2,500 cfs. The minimum monthly mean flow for these four months was 3,515 cfs (August 1977). There were three days in December 1980 on which the daily flow was less than 2,500 cfs; the monthly mean flow for December was 3,784 cfs. According to the published USGS records, there were only two months in 1981, not three--as stated by the DOI, during which a daily flow was less than 2,500 cfs. In January 1981, the flow at Trenton was below 2,500 cfs on 13 days; the mean flow for the month was 2,539 cfs. In February 1981, for which
e i Table 1.--Delaware River at Trenton, N. J.-- , Daily Mean Flows.less than 2,500 cfs, with Monthly Means Flow for such Occurrences, 1977, 1980, and 1981 Mean flow, Mean flow, Date(s) cfs Date(s) cfs Jan. 31, 1977 2,250 Jan. 5, 1981 1,900 Jan. 1-31, 1977 3,755 Jan. 6, 1981 2,280 Jan. 9, 1981 2,400 Feb. 1, 1977 2,200 Jan.10,1981 2,430 : Feb. 1-28, 1977 7,511 Jan. 11,1981 2,330 i Jan . 12,1981 2,350 July 29, 1977 2,440 Jan.13,1981 2,210 July 1-31, 1977 3,723 Jan.14,1981 2,370 Jan.15,1981 2,430
- Aug. 30, 1977 2,490 Jan.18,1981 2,420 Aug. 1-30, 1977 3,515 Jan. 31,1981 2,410 Jan. 1-31, 1981 2,539 Dec. 22, 1980 2,420 Dec. 23, 1980 2,370 Feb. 1, 1981 2,280 Dec. 27, 1980 2,390 Feb. 1-28, 1981 22,790 Dec. 1-31, 1980 3,784 :
Jan. 3, 1981 2,400 Jan. 4, 1981 2,150 Source: U. S. Geological Survey 1 I e-w-- -v ns--m , m -w m e--v 4,m .-+-,v,,,._ - . , ~ .n,,,n,y-e,,wr -v, ----,-~,,,,,,,1m.,, p.,, - - , , _ m,gyy--my-4e, ,--~w--p---,,vn-,m,,wn.,,.w.,
the Trenton flow averaged 22,790 cfs, there was only one day on which the daily mean flov was less than 2,500 cfs. The inf requent low daily flows listed in table 1 do not represent severe problems. There were only 21 days in the five year period from 1977 through 1981 with daily Trenton flows less than 2,500 cfs. There were seven months during this five year period during which the flow dropped below 2,500 efs for one or more days. Five of these months and 19 of the 21 days were either in January or February, the time of year when low river flows are not critical with respect to the needs for protection of stream uses. Only two of the low-flow days, one in July 1977 and one in August 1977, occurred in the critical summer period when stream values are sensi-tive to flow levels. With mean monthly flows of 3,723 cfs and 3,515 cfs, respectively, for these months, the isolated one-day flow deficiencies would not cause any problems in the river or estuary. For example, the single low-flow in July 1977 (2,440 cfs on July
- 29) would not cause a salinity change in the Delaware estuary; the salinity at any time is dependent on a long series of antecedent flows over several months. Thus, if the flow on July 29 had been increased to 3,000 cfs, it would not have resulted in a significant change in estuarine salinity.
Cause of low flows.--The DOI seems to imply that the observed occasional daily flows below 2,500 cfs in 1977, 1980, and 1981 resulted from inadequate stora ge capacity. However, this was not the case. The reason the Trenton I flow was occasionally less than the objective is related to difficulties experienced by the Deputy Delaware River Master in scheduling reservoir releases to meet the minimum flow objective at Monta gue , N.J., where compliance with the Monta gue formula for minimum flow, as specified in the 1954 decree of the U.S. Supreme Court, is checked. Any flow deficits from this cause at Monta gue are reflected in the flows measured at Trenton about two days later. The Deputy River Master is an employee of the Department of Interior. If these deficits had been significant, they could have been offset by releases from Beltzville Reservoir on the Lehigh River, where water was available in storage. However, whenever design releases (basic releases plus excess releases) directed by the River Master prove to be too low to meet the
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Montague flow objective, extra releases are scheduled by the River Master over the next 10 days or more to maintain the average flow at or above the objective. The DRBC is currently conferring with the River Master's office to improve the scheduling of releases from New York City's upper-basin reservoirs as necessary to decrease the already low frequency of flow deficits at Montague. In the meantime, it should be emphasized that although operational problems have led to infrequent flow deficits at both Montague and Trenton, these operational problems are subject to better control. Moreover, because of their infrequent occurrence, short duration, or season of occurrence, they 4 have not resulted in any detectable problem related to instream water uses. The DOI states that the DRBC "...now admits (emphasis added) that by the year 2000, they may not be able to maintain 2,300 cfs flow at Trenton because
,, of increased consumptive losses in the Basin...", and that "...the DRBC recognizes that several more large reservoirs must be constructed in the basin to achieve the minimum flow objectives at Trenton." It is misleading to charactize these lon g-known facts, widely proclrimed by the DRBC icr many years, either as recent or as an admission. Since 1962, the DRBC has called for additional reservoirs in the Basin to augment low flows of the Delaware 4
River. More recent projections of demand have allowed delays in construction of additional storage capacity. However, as a result of recommendations in the final Level-B report and the " Good Faith" report, the DRBC has four additional storage projects planned for develcpment by the year 2000. What the DOI has failed to state in DRBC 's management of the Delaware River, is that even if minimum daily flows fall to the 2,400 to 2,500 cfs levels during a drought emergency, that minimum flow level is n. ich greater than the 1,100 cfs drought-flow levels available before upstream impot.a'ments gave us an increased flow-maintenance capability. And, this more than doubling of minimum reliable flows (2,500 cfs vs 1,100 cfs) helps all instream uses, including fish, wildlife, and recreation. Relation of low flows to Limerick project.--The DOI comments regarding observed Trenton flows less than 2,500 cfs ha.1 little relevance to the l
decision to be guided by the environmental impact statement. The DRBC has specified that whenever the Trenton flow is less than 3,000 efs, water can be diverted from the Delaware River for use at the Limerick generating station only if the diverted water is replaced from storage, that is, from Merrill Creek Reservoir or an alternate facility. Therefore, the Trenton flows below 3,000 cfs will not be reduced by the Limerick diversions. Perkiomen Creek flows.--The DOI suggested clarification of the re-quirements for maintenance of flows in Perkiomen Creek and its East Branch. The pumping rate of 27 cfs applies to the withdrawal from the Delaware River. No rate is specified for withdrawals from Bradshaw Reservoir, but these withdrawals must be adequate, when combined with natural runoff in the East Branch, to give a flow of 27 cfs in the East Branch at the Bucks Road stream ga ge. The DRBC approval of the Bradshaw Reservoir water supply is subject to various conditions, including maintenance of a minimum flow of 27 cfs in the East Branch Perkiomen Creek throughout each low flow period when pumping from the Delaware River is required for the operation of the Limerick generating station. The rest of the year PECO must maintain a minimum flow of 10 cfs in the East Branch. There is no requirement for Bradshaw Reservoir releases to maintain low flows in the main stem of Perkiomen Creek. However, augmentation of low flows in the East Branch will incidentally augment the flows in the main stem. (See DRBC Docket No. D-79-52 CP--Bradshaw Reservoir, etc.) The DRBC approval of the water supply for the Limerick generating station (Docket No. D-69-210 CP(Final)) specifies that Perkiomen Creek may be used as the source when flows as measured at the Graterford gage are in excess of 180 cfs with one generating unit in operation or in excess of 210 cfs with two units in operation. l Potential water loss.--The DOI suggested that the estimated 10 percent loss of water in transport from the Delaware River to the Limerick station may be conservative (low), considering evaporative losses in Bradshaw Reservoir and over 23 miles of Perkiomen Creek, leakage from transmission pipes, channel storage, and grcund-water intrusion.
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The greatest transit loss by evaporation will be from the surface of Bradshar Reservoir, with a surface area of 18 acres. Based on a maximum evaporation rate of 0.25 inches per day, this loss will not exceed 0.122 mgd I (0.2 cfs). f 4 The evaporative transit losses in the East Branch Perkiomen Creek and in the short reach of Perkiomen Creek between the East Branch and the withdrawal . intake will be a function of temperature and incremental water-surface area added to these stream reaches by the flow augmentations from Bradshaw Reservoir. Except in short reaches where the natural streambed is dry, flow augmentation will add very little surface area, and the stream temperature
- will not be increased significantly. Therefore, flow augmentation will cause very little incremental evaporation from the streams used for conveyance.
3 The DOI expressed concern tnat transit losses may be higher than 4 estimated because of potential seepage through the streambed to nearby overpumped aquifers. The total stream loss to the aquifers is a function of the ares of the wetted permeable streambed and the hydraulic gradient between the stream surface and the water table in the aquifer, The incremental wetted streambed and incremental hydraulic head will be very small for the stream conveyance system. Therefore, the increase in stream losses to aquifers attributable to flow augmentations will be correspondingly small. The maximum withdrawal from Perkiomen Creek for supplemental cooling water (42 agd) was determined by combining the maximum evaporative loss in the
- cooling system with the maximum miscellaneous and drif t loss at the Limerick l station, even though these losses are not expected to occur concurrently (see DES, section 4.3.1.2, page 4-24). The transit-loss allowance of 4.2 mgd (6.5 l cfs) is 10 percent of the conservatively high estimate of 42 mgd for the
! Perkiomen Creek withdrawal. The Point Pleasant pumping station is sized to j withdraw 46.2 mgd from the Delaware River, including the liberally estimated !' increment of 4. 2 mgd for transit losses. If, as expected, the actual f evaporative losses, etc., at the Limerick station are less than 42 mgd, the , difference between the Delaware River withdrawal and the actual station losses will be greater than 4.2 mgd, and this difference--available to offset transit lossess--will be greater than 10 percent of the Perkiomen Creek withdrawal.
The DRBC staff believes the allowance for 10 percent transit losses is r reasonable, and probably conservatively high. ? - Aquatic Resources Even though the Point Pleasant area might be more heavily used for alosid spawning in the future, the Point Pleasant intake is state-of-the-art to minimize impingement and entrainment, and hundreds of miles of main stem and tributaries are already used as spawning grounds. Operation of the intake at Pt. Pleasant is insignificant when considering the remaining vast spawning areas, and exploitation of female shad by commercial and sport fisheries. , Water use and treatment The DOI compared the maximum withdrawal from the Delaware River at Point Pleasant as noted on page 4-10 of the DES (71 cfs) with the maximum use of 4 Delaware River /Perkiomen Creek water at the Limerick generating station as given in table 4.1, page 4-4 (57.4 cfs), and concluded that this means a 4 transit loss of the difference (13.6 cfs). The Point Pleasant withdrawal figure on page 4-10, 71 cfs, is rounded to the nearest efs. If_ the transit
- loss is to be calculated to the nearest tenth of a cfs, then the Point Pleasant withdrawal should be taken as 71.5 cfs, and the difference between
, 71.5 cfs and 57.4 cfs would be 14.1 cfs. However, it does not follow that the transit loss should be calculated as the difference between the two maximums, which may not occur concurrently. It would be more appropriate to compare
- average Point Pleasant withdrawals (56.3 cfs) with average consumptive water losses at the Limerick station (50.7 cfs) to get an indication of expected transit losses. By this calculation, the apparent transit losses would average 5. 6 cfs. This is approximately 11 percent of the average consumptive losses at the Limerick station; 11 percent is reasonably close to the estimate of 10 percent transit losses added to the proposed Perkiomen Creek withdrawal of 42 mgd for the purpose of sizing the intake facilities on the Delaware
[ River. l l-We think the information on water losses is clear enough, ar.d not very critical in the decision on issuing an operating license for the Limerick station. The DOI, referring to table 4.1 of the Draft EIS, interpreted the table to mean that water will not be drawn from the Delaware River from November through May, and noted that because Schuylkill River flows have dropped below 530 cfs at Pottstnwn in nearly every month of the year, pumping froth the Delaware may be required year-round to meet DRBC requirements. We interpret table 4.1 to represent an average year, based on the statement on page 4-3 that:
" Based on historical flow records, the applicant anticipates that virtually all of the water supplied to Limerick to replace consumptive losses. . .during the period June through Octoba- of an a ve ra ge year will come f rom the Delaware River /Perkion m Oreek System because of the DRBC restrictions. During the remainder of the year, the applicant anticipates that there will be no use of these waters by Limerick." (Emphasis added.)
The DRBC has not assumed that there will never be any use of Delaware River water in the period from November though May for consumptive-use replacement at Limerick, and the DRBC has not imposed any such restriction. The only restriction, which will apply year-round, is that unless compensated by releases from stora ge , Point Pleasant diversions to Limerick must occur only when the flow of the Delaware River at Trenton exceeds 3,000 cfs. Actually, November-to-May low flows in the Schuylkill River are not as frequent as might be inferred from the DOI comment. Table 2 shows natural runoff at Pottstown, data developed for the DRBC by the U.S. Geological Survey for the 52-year period from 1923 through 1974. These data are monthly flows ranked from lowest to highest for each calendar month from November thraugh May. For these months, only November and December had monthly flows less than 530 cfs. November flows averaged less than 530 cfs in 7 out of 52 years; December flows in 3 out of 52 years. Based on data for the entire 52 year period (624 months), the median monthly flow was 1,545 cfs. Although these statistics are for monthly flows, they do suggest that winter and spring flows less than 530 cfs are unusual.
As indicated in table 2 5 water year 1931 was a very dry period for the Schuylkill River at Pottstown; the monthly flows for this year ranked first
.(driest) for November, December, and March; second for January; and third for February. It is of interest to know how of ten during such a dry year the daily flow at Pottstown would be less than 530 cfs. Table 3 lists the daily flows for November through May of water year 1931. The number of days with flows less than 530 cfs in each month were as follows:
Nov. '30 Dec. '30 Jan. '31 Feb. '31 Mar. '31 Apr. '31 May '31 29 27 17 9 3 0 0 j These data indicate that in an extremely dry period like water year 1931, the use of Schuylkill River water might be prohibited because of low flow as often as 85 days from November through May, or 40 percent of that seven-month period. For less severe drought periods, the use of Schuylkill River water for replacement of evaporative losses a't Limerick would be prohibited less fre-quently than indicated for 1931. In most years there would be little or no need to prohibit Schuylkill River withdrawals at Limerick except in November. This is supported by tables 4 and 5, which show daily flow data for the Schuylkill River at Pottstown for November through May in relatively . dry years. Table 4 shows the number of days on which the flow was less than 530 cfs for the fif th driest calendar month among 52 months with the same name l from 1923 through 1974. Table 5 shows the same statistics for the tenth driest calendar month. Daily flows less than 530 cfs occurred on as many as 26 days in the fifth driest November and as few as 1 day in the fifth driest February (with none in April or May). For the " tenth driest" category, flows less than 530 cfs occurred on 24 days in November and 5 days in December (with l none in the tenth driest January, February, March, April, or May). t Table 6 shows similar statistics for the 25th driest month for each of l the seven calendar months from November through May. There were seven days in the 25th driest November (1968) on which the daily flow at Pottstown was less than 530 cfs. There were no such days in the 25th driest December, January, February, March, April, or May. l
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Table 2.--Schuylkill River at Fottstown, Pa. Ranked Monthly Mean Natural Runoff Nov, ember throuch May--1923 throueh 1674 Water Water Water Water Water Water Water Park Nov. Year Dec. Year Jan. Year Feb. Year Mar. Year Agr. Year May Year 1 309 1931 419 1931 627 1940 537 1934 1360 ,31 1150 1965 725 1963 2 314 1932 434 1923 687 1931 862 1923 1420 969 1240 1966 739 1941 3 372 1965 528 1932 695 1925 953 1931 1600 1965 1310 1923 810 1926 4 398 1923 604 1929 729 1956 1000 1969 174u 1949 1359 1963 994 1962 3 408 1942 632 1966 878 1966 1120 1944 1950 1934 1360 1925 1010 !?55 6 474 1966 650 1961 904 1969 1210 1932 1960 1960 1440 1946 1110 1959 7 507 19?7 690 1934 977 1965 1220 1940 1990 1937 1510 1931 1160 1957 8 543 1950 769 1947 985 1970 1270 1963 2040 1957 1580 1971 1170 1935 9 583 1929 805 1967 1070 1923 1330 1967 2070 1959 1610 1968 1190 1969 10 586 1967 835 1940 1100 1942 1350 1946 2200 1963 1630 1942 1190 1963 11 657 1924 840 1944 1120 1943 1490 1924 2220 1970 1680 1926 1200 1938 12 711 1947 909 1965 1140 1954 1510 1954 2290 1932 1740 1927 1240 1951 13 755 1940 939 1956 1190 1961 1750 1947 2340 1938 1810 1938 1300 1930 14 755 1962 971 1964 1320 1945 1780 1955 2390 1973 1820 1967 1420 1936 15 765 1934 986 1962 1320 1955 1820 1964 2390 1947 1980 1954 1430 1939 16 768 1964 1040 1942 1360 1929 1830 1959 2470 1966 2000 1950 1590 1966 17 775 1958 1100 1925 1370 1968 1870 1942 2520 1930 2020 1955 1610 1970 18 812 1945 1100 1948 1690 1963 1870 1941 2600 1928 2050 1941 1630 1925 19 851 1961 1240 1959 1520 1967 2060 1968 2620 1925 2070 1969 a750 1949 20 859 1954 1330 1950 1560 1957 2120 1957 2640 1935 2090 1943 1790 1923 21 883 1925 1330 1930 1580 1933 2170 1930 2670 1941 2220 1945 1790 1934 22 969 1970 1480 1955 1670 1959 2220 1929 2690 1927 2270 1947 1800 1931 23 999 1974 1530 1933 1720 1941 2230 1936 2850 1926 2330 1930 1810 1927 26 1150 1955 1540 1938 1730 1930 2240 1933 2900 1942 2390 1972 1830 1956 25 1270 1969 1580 1963 1730 1944 2280 1938 2910 1974 2430 1959 1880 1932 26 1300 1968 1680 1970 1740 1971 2300 1958 3020 1943 2440 1935 1900 1971' 27 1400 1960 1700 1969 1750 1939 2310 1974 3100 1951 2500 1932 1920 1974 28 1430 1949 1730 1936 1770 1926 2370 1948 3170 1964 2560 1956 1920 1937 29 1430 1959 1810 1971 1810 1950 2400 1962 3230 1955 2770 1962 2030 1961 30 1470 1939 1870 '1927 1850 1928 2450 1935 3260 1954 2840 1949 2080 1950 31 1710 1935 2040 1945 1900 1932 2480 1927 3280 1950 2850 1937 2110 1968 32 1800 1936 2090 1941 1930 1947 2600 1945 3350 1945 3030 1951 2160 1940 33 1940 1936 2220 1937 1940 1935 2610 196i 3370 1956 3250 1929 2160 1960 34 1960 1930 2390 1926 2200 1927 2700 1972 3380 1946 3320 1964 2170 1944 35 2140 1943 2430 1968 2230 1962 2750 1965 3510 1948 3490 1944 2240 1929 36 2200 1957 2610 1949 2360 1938 2770 1960 3570 1944 3510 1939 2320 1954 37 2240 1946 2910 1946 2390 1934 2920 1956 3590 1939 3530 1961 2680 1967 38 2240 1956 2970 1972 2430 1972 2970 1937 3660 1929 3690 1953 2740 1943 39 2270 1941 3010 1958 2450 1958 3090 1943 3680 1962 3700 1948 2770 1964 40 2330 1928 3140 1954 2540 1960 3110 1952 3810 1961 3910 1936 2850 1928 41 2440 1963 3200 1957 2670 1946 3190 1949 3920 1971 3940 1934 2950 1972 42 2830 1972 3350 1760 2870 1943 3340 1953 3950 1933 3980 1928 3090 1945 43 3060 1948 3313 1943 2880 1951 3560 1961 4130 1967 4000 1960 3100 1946 44 3190 1926 3430 1935 3130 1964 3670 1950 4150 1952 4030 1974 3110 1933 45 3210 1953 3720 1952 3340 1974 3720 1973 4250 1953 4160 1958 3190 1973 46 3220 1944 3780 1939 3410 1936 3740 1970 4250 1972 4580 1957 3320 1958 47 3400 1971 3o70 1933 3930 1973 3740 1926 4380 1924 4800 1973 3950 1953 49 3530 1973 4120 1928 4020 1937 4380 1928 4430 1940 4890 1470 4070 19*2 49 3720 1952 4190 1924 4270 1953 4560 1939 4590 1958 5150 1933 4450 1948 50 3760 1933 4640 1951 4680 1952 4760 1951 4690 1963 5240 1952 l 4460 1947 51 3930 1951 4740 1974 4800 1949 5140 1971 5350 1923 5470 1940 4880 1924 l 52 4210 1927 4880 1973 4830 1924 6920 1925 9010 1936 5510 1924 I 5380 1942 Source: U. S. Geological Survey. 1975. Natural Flow Project, Delaware River Basin; Prepared for Delaware River Basin Commission, Trenton, K.J. L
Table 3.--Daily Flows in Schuylkill River at Potgstown, Pa. , November through May, Water Year 1931 Nov. Dec. Jan. Feb. Mar. Apr. May Day 1930 1930 1931 1931 1931 1931 1931 1 246 300 364 376 578 3270 803 2 288 453 300 349 636 4400 820 3 248 369 260 325 622 3380 873 4 268 314 260 304 564 2980 847 5 249 294 400 299 509 2540 761 6 278 347 2550 309 515 2140 713 7 254 358 1800 320 466 2010 1000 8 258 347 714 226 1290 2080 2660 9 247 336 622 388 3250 1700 3900 10 249 314 593 754 2080 1500 3340 11 254 309 510 605 1490 1380 2830 12 254 260 480 552 1220 1240 2400 13 261 283 440 612 1060 1130 2650 14 276 294 400 1810 976 1050 3900 15 310 213 360 1320 928 986 3470 16 358 200 340 905 910 928 2830 17 392 184 340 1040 1000 882 2400 18 673 294 468 5200 1060 864 2140 19 4d4 274 1290 2880 1100 794 1820 20 386 273 2070 1600 1170 770 1640 21 358 272 1120 1220 1120 720 1710 22 316 248 678 986 1130 678 1850 23 292 240 562 864 1130 916 1620 24 291 244 523 794 1060 1090 1580 25 310 328 451 736 1130 722 1320 26 317 260 420 674 1290 821 1240 27 300 1330 518 629 1180 1220 1110 28 280 1900 697 600 1100 1120 1000 29 274 976 649 -- 3950 948 910 30 302 644 537 -- 4350 919 838 31 -- 518 426 -- 3300 -- 829 l
- Source: Pennsylvania Dept. of Forests and Waters. 1933. Stream Flow Records for the Four Years: October 1, 1928, to September 30, 1932; Harrisburg, Pa.
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s t i Table 4.-Schuylkill River at Pcttstown, Pa. Daily Flows in 5th Driest Calendar Month. November throuah May. for the Period 1922 throuah 1974* I observed Daily Flows, cfs 5th Driest 5th Driest 5th Driest 5th Driest 5th Driest 5th Driest 5th Driest November December January February March April " May Dag (1941) (1965) (1966) (1944) (1934) (1925) (1955) 1 445 583 628 1090 420 2 815 561 668. 930 500 3 756 554 1190' 970 1500 4 510 547 1090 960 5500 5 460 525 868 890 6500 6 418 518 1210 815 3730 7 481 490' 1760 779 2400 j 8 532 477 1500 738 1820 453 456 676 1500 9 1290 10 386 456 1230 607 1430 11 360 463 1240 648 1220 12 366 525 964 490 1190 " " 13 340 665 834 562 1300 *
- 14 347 792 919 594 1640 15 340 712 928 851 1460 2 R
16 314 642 809 1130 1320 17 295 605 704 1090 1290 $ E 18 295 590 696 1330 1330 0 5 19 293 568 650 2150 1440 a e 20 302 554 650 1290 1380 0 E i 21 314 540 620 1130 1290 22 23 308 416 490 484 590 635 1130 1460 1260 1190 l l 4 '
- 1 24 541 511 590 1840 1050 25 492 580 598 1450 1040 2 2 j 26 399 1070 561 1350 1160
- - 27 373 866 532 1710 1260 28 360 704 490 1940 4070 i
29 328 673 480 1810 3280 30 328 635 470 -- 2610 31 -- 620 460 -- 3400 Minimum 293 456 460 490 420 889 705 Maximum 815 1070 1760 2150 6500 2077 1560 Mean 412 595 834 1118 1951 1330 1009 No. of days with flow lessthgn 4 0 0 l 530 cfs 26 11 1 2
- Source: U. 5. Geological Survey b
Minimum flaw at Pottstown gage from which make-up water for Limerick power station can be taken from Schuylkill River
- Daily discharte data were not available for Pottstown gage; data shown were computed, based on daily flows in the Schuylkill River at Reading Pa. g e
l _14_
e 6 Table 5.-Schuylkill River at Pottstown, Pa. Daily Flows in 10th Criest Calendar Month. November through May. for the Period 1922 through 1974* Observed daily flow. efs 10th driest 10th driest 10th driest 10th driest 10th driest 10th drfest loth driest November December January February March April May g (1966) (1939) (1942) (1946) (1968) (1942) (1963) 1 33* 492
+ 2 371 542 3 436 814 4 566 731 5 513 595 6 423 535 7 409 513 8 396 471 9 396 430 10 450 450 11 572 535 12 632 603 e y a e .
13 556 535 w w w w w 14 477 659 R g g g g 15 429 651 e e e o n 16 423 372 a a e = , 17 416 528 S S S S S
* * ~
- 18 423 550 19 436 520 I I I E I 20 409 1090 $ 0 $ $ $
21 383 2900 m e e e e 22 377 2080 $ $ $ $ $ 23 377 1580 W G C ; O 24 371 1260 g j g g g 25 377 1020 26 443 1100 27 457 980 28 879 832 29 2650 868 30 2030 885 31 - 772 Minimum 339 430 650 1020 843 945 822 Maximum 2650 2900 2010 3220 6560 2550 2200 Mean 580 841 1109 1355 2198 1712 1188 No.of days with flow less than 23 5 0 0 0 0 0 530 efs a source: U. S. Geological Survey Minimum flow at Pottstown gage from which make up water for Limerick power station can be taken from the Schuylkill River. r l l l I Table 6.-Schuylkill River at Pottstown, Pa. Daily Flows in 25th Driest Calendar Month. November through Mav. for the Period 1922 through 1974* Observed daily flows, cfs 25th driest 25th drisat 25th driest 25th driest 25th driest 25th driest 25th driest November December January February March April May M (1968) (1962) (1944) (1938) (1974) (1959) (1932) 1 499 2 485 3 506 4 506 5 492 6 478 7 513 8 603 9 627 10 864 11 1190 12 1390 13 1520 IN IE00 0u 0u 0v 0v 0v 0u 15 1170 16 1400 g g g g g g 17 1700 e e o e e e 18 2200 g g g g g g 19 3200 e" e e e~ e e
~ ~ ~ ~
20 2700 21 2200 I I I I I I 22 1900 3 3 3 3 3 3 23 1700 m a e e e a 24 1500 $ $ $ $ $ $ 25 1300 26 1200 g g g j j j 27 1100 28 1000 29 1500 30 1200 31 - Minimum 478 700 696 1450 1660 1360 1940 Maximum 3200 5370 6560 3550 6220 5630 6350 Meen 1264 1587 1726 2275 2911 2433 3110 No. days with flow lessthgn 530 cfs 7 0 0 0 0 0 0
- Source: l'. S. Geological Survey b
Minimum flow at Pottstown gage from which make up water for Limerick power station can be taken from Schuylkill River.
It should not be inferred from table 6 that daily flows less than 530 cfs occurred in every November drier than the 25th driest November. Because the rankings of months are based on monthly average flows, there can be Novembers drier than the 25th driest November in which the minimum daily flow exceeds 530 cfs. Conversely, there can be minimum daily flows less than 530 cfs in a November ranking wetter than the 25th driest. Table 7 shows the minimum daily flow for each ranked November monthly flow for the 52 year period from water-year 1923 through water year 1974. Among these 52 Novembers, there were 22 Novembers in which the daily flow wac less than 530 cfs on one day ce more. The wettest November with daily flows less than 530 cfs was the 32nd driest November. The streamflow data for the Schuylkill River at Pottstown indicate that the low-flow period--with flows less than 530 cfs--can be expected to extend into November in about 42 percent of the years (22 out of 52). It can be expected to extend less frequently into December. Occasional daily flows less than 530 cfs can occur in any month of the year, but when they occur on scattered days from January through May, they should not be considered as part of the normal low-flow period. Pumping during low-flow period.--The 1975 DRBC approval of the water supply for the Limerick Generating Station (Docket No. D-69-210 CP--Final) specifies that a minimum pumping rate of 27 cfs shall be maintained during the normal low-flow period. The later (1981) DRBC approval of the Bradshaw Reser-voir and its associated pumping station (Docket No. D-79-52 CP--Condition B) affirms that "The withdrawal of water f rom the Delaware River at the Point Pleasant Pumping Station for diversion into the East Branch Perkiomen Creek must conform with the schedule and conditions listed in DRBC Docket D-69-210 CP." However, a related new condition (Condition C) in the 1981 approval was that "PECO shall maintain a minimum flow of 27 cfs (17.4 mgd) in the East Branch Perkiomen Creek at the proposed Bucks Road stream gage throughout the normal low-flow period beginning with the day the booster commences pumping and ending when pumping is no longer required for the operation of the Limerick Generating Station. The rest of the year PECO shall maintain a minimum flow of 10 cfs (6. 5 mgd ) . " Thus, during the normal low-flow period, the minimum PECO diversion from the Delaware River to Bradshaw Reservoir will
Table 7.-Schuylkill River at Pottstown Pa.- Ranked Mean November Flows and Minimua Daily Flow for each November Water-Tears 1923 throuah 1977 No. of November Minimum days with flow _Mean November flow daily flow less than Rank cfs efs 530 efs Water year (1) M (3) (4) (5) 1 309 246 29 1931 2 314 240 30 1932 3 372 215 27 1965 4 398 195 30 1923 5 408 293 26 1942 6 474 377 23 1966 7 507 331 22 1937 8 543 428 16 1950 9 583 468 10 1929 10 586 339 23 1967 11 657 403 13 1924 12 711 595 0 1947 13 755 457 10 1940 14 755 403 11 1962 15 765 614 0 1934 16 768 308 18 1964 17 775 391 10 1958 18 812 390 20 1945 19 851 663 0 1961 20 859 476 3 1954 21 883 720 0 1925 22 969 491 2 1970 23 999 734 0 1974 24 1150 477 6 1955 25 1270 478 7 1969 26 1300 656 0 1968 27 1400 803 0 1960 ' 28 1430 502 3 1949 29 1430 753 0 1959 30 1470 971 0 1939 31 1710 1030 0 1935 32 1800 411 10 1936 33 1940 1090 0 1938 34 1960 910- 0 1930 35 2140 1250 0 1943 36 2200 1200 0 1957 37 2240 920 0 1946 38 2240 1340 0 1956 39 2270 814 0 1941 40 2330 1050 0 1928 41 2440 1200 0 1963 42 2830 1040 0 1972 43 3060 870 0 1948 44 3190 1040 0 1926 45 3210 620 0 1953 46 3220 1180 0 1944 47 3400 847 0 1971 48 3530 586 0 1973 49 3720 1770 0 1952 50 3760 1640 0 1933 i 51 3930 686 0 1951 52 4210 1297 0 1927 Source: U. S. Geological Survey
)
be 27 cfs, and the minimum flow in the East Branch Perkiomen Creek will be 27 ' cfs as measured at the stream gage at Bucks Road. These are two distinct, l though related, requirements. At times when there is measureable natural runoff in the East Branch at Bucks Road, the booster pumps at Bradshaw will not have to move the full 27 cfs from the reservoir into the East Branch. Pumping durfylgh-flow period.--The DOI asked for clarification of the pumping requirer ants een the Schuylkill River flow is too low to permit the use of Schuylki13 water for make-up of consumptive water use at the Limerick Station during the period from November through May. As explained earlier herein, the low-flow period in the Schuylkill will extend beyond October into November about 42 percent of the years, and when this occurs, the udnimum pumping rate of 27 cfs from the Delaware will be required, as well as the Bucks Road minimum flow of 27 cfs. These two minimum rates would prevail until the late fall or early winter when PECO switches back to the Schuylkill River. Af ter that switch, the normal low-flow period will be over, and subse-quent occasional Schuylkill flows below 530 cfs will be considered to be occurring in the normal high-flow period. For these low flows during the normal high-flow period, no minimum pumping rate from the Delaware is speci-fled, but a reduced minimum flow of 10 cfs must be maintained in the East Branch Perkiomen Creek throughout the normal high-flow period. Thus, pumping f rom the Delaware River to meet PECO requirements during the high-flow season will be the greater of two rates: (1) the rate required to maintain a minimum flow of 10 cfs at the Bucks Road gage; or (2) the rate required to meet the Limerick requirement for make-up water plus transit losses. l It should be noted that during the normal low-flow period the required minimum rate of pumping from the Delaware River, 27 cfs, will be greater than the required rate of pumping f rom Bradshaw Reservoir at times when there is natural runoff in the East Branch Perkiomen Creek as measured at the Bucks j Road gaging station. This would tend to raise the water level in Bradshaw Reservoir, and eventually might cause the Reservoir to overflow unless the Delaware River pumping were curtailed. As the purpose of the minimum Delaware pumping rate of 27 cfs was intended only to ensure a minimum flow of 27 cfs at l the Bucks Road gage , it would be undesirable and wasteful to continue pumping the full 27 cfs from the Delaware River if 27 cfs could be sustained at the
Bucks Road gage with a lesser pumping rate from Bradshaw Reservoir whenever that reservoir is full. Therefore, when the East Branch flow is 27 cfs or greater and Bradshaw Reservoir is full, the pumping of Delaware River water to meet PECO's requirements should be stopped. This will decrease the hazards of impingement and entrainment of aquatic organisms at the Delaware River intake. In summary, the low-flow period in the Schuylkill River will extend into the month of November in about 22 years out of 52, based on natural flow studies for the period from water year 1923 through water year 1974 Much less frequently, the low-flow period will extend into December, during which Pottstown flows will be below 530 cfs on five days in about 10 years out of 52 years--or approximately 1 year out of 5. Occasionally, we may expect these low flows to occur on a few days in calendar months as late as March or April. When Schuylkill River flows are too low to allow withdrawals for replacement of consumptive use during the period from November through May, the alternative sources will be available for use under the same restrictions and limits as during the period from June through October, even though the
-need for such restrictions would be generally somewhat less in late fall, winter, and early spring than from June through October. Therefore, the DRBC staff sees no need to be concerned that the low-flow period in the Schuylkill l River will in some years extend beyond October, or that occasionally there may be isolated low-flow days in any of the months f rom November through May.
Water quality ,. The DOI expressed concern about the quality of Delaware River water to be l l diverted into Perkiomen Creek. l Sampling.--The DOI observed that the data used by the DRBC and the Pennsylvania Department of Environmental Resources (PADER) were from monthly grab samples and some 24-hour couposite samples. The DOI stated that grab samples are inadequate for representing the quality of flowing water, and that only continuous monitoring could achieve the accuracy implied by the DES. l l l .-- - , . - - - - . . . . - - . . , _
I I This comment is not consistent with accepted water quality assessment methods. Continuous monitoring is practical for only a very few water quality parameters, and continuous monitoring for those parameters is rarely practiced. Generally, the characterization of the quality of surface waters in the United States is based on periodic rather than continuous sampling. The use of the same grab-sample technique in the East Branch Perkiomen and Perkiomen Creeks, as well as in the Delaware River, tends to rule out errors in sampling for purposes of comparing quality in these streams. Me tals .-The DOI stated that although Delaware River water quality has been described as very good, there is evidence of pollution by at least two metals, cadmium and lead. Concentrations of metals found in the Delaware River at Point Pleasant are generally similar to concentrations found in the East Branch Perkiomen Creek. In some cases, including cadmium and lead, higher concentrations were reported in Perkiomen Creek. Cadmium concentrations ranged from 0.000 to 0.013 mg/l in the East Branch and from 0.000 to 0.010 mg/l in the Delaware River. Lead concentrations ranged from 0.000 to 0.060 mg/l in the East Branch and from 0.000 to 0.020 mg/l in the Delaware. (See Applicant's Environmental Report, tables 2.4-15 and 2.4-16.) The major source of lead found in surface waters is the atmosphere, which derives most of its lead f rom the use of leaded gasoline by motor vehicles. The use of leaded gasoline is being phased out gradually, and this is expected to reduce lead concentrations in the atmosphere and in surface waters. Phosphorus.--The DOI expressed concern that high levels of phosphorus in Delaware River water might cause algal blooms in Bradshaw Reservoir, degrading water quality and causing anoxic conditions in water discharged to Perkiomen Creek. Anoxic conditions, if they occurred in the reservoir water, would be eliminated quickly by aeration at the energy-dissipation facilities at the outlet of the pipeline discharging into the East Branch Perkiomen Creek. Because of the oxygen-demanding waste load discharged from local sources along
o the East Branch, any oxygen deficit in that stream is more likely to be caused by these local sources. Rather than increasing dissolved-oxygen deficits in the East Branch or main stem of the Perkiomen, the diversion is expected to improve dissolved-oxygen levels in these streams, especially during the critical warm, low-flow season when dissolved-oxygen levels are most likely to be depressed significantly. Chemical spills.-The DOI expressed concern that a chemical spill at the Route-32 bridge across Tohickon Creek would travel quickly dowastream and be drawn into the Point Pleasant intake, which is only 800 feet downstream of the mouth of Tohickon Creek, thereby contaminating Bradshaw Reservoir, and eventually Perkiomen Creek. Any chemical spill from the Route-32 bridge would be subject to dilution in Tohickon Creek and in the Delaware River before reaching the Point Pleasant intake. Additional dilution by mixing would occur in Bradshaw Reservoir. On the other hand, the East Branch Perkiomen Creek is crossed by Routes 313, 152, 309, 63, the Northeast Extension of the Pennsylvania Turnpike, and the Reading Railroad. Chemical spills at these crossing -some of which are much more heavily traveled than the Tohickon crossing--would receive less dilution than spills reaching the Delaware, and the diversion of Delaware River water into the East Branch would provide dilution of the chemicals spilled locally. In fact, the existence of the diversion facilities would make it possible to dilute local spills beyond the level provided by the flow augmentation of Perkiomen Creek and its East Branch for Limerick water supply alone, if in an emergency this were desirable. Environmental consequences Percenta ge withdrawal.--The DOI states that to calculate the highest possible percenta ge of the Delaware River flows that would be withdrawn by Limerick, a flow of at least 3,000 cfs is assumed to be maintained at Trenton, and notes that flows less than 3,000 cfs are not uncommon in the USGS gaging records. The D01 notes that the Trenton flow dropped to 1,900 cfs in January 1981, and states that the extremes most significantly affect fish and wildlife resources.
It is somewhat misleading to cite observed historical flows in a regulated stream for which the degree and method of regulation will be different in the future. Nevertheless, under the recently adopted reservoir operating rules for basin reservoirs in future droughts (DRBC Resolution 83-13, June 1983), the regulated flow objective for the Delaware River at Trenton will be as low as 2,500 cfs. This is indeed less than 3,000 cfs. However, the DRBC has prohibited Delaware River withdrawals for the Limerick station when such withdrawals would result in Trenton flows less than 3,000 cfs. The base flow to be used in calculating the percentage of river flow withdrawn at Point Pleasant depends on the purpose of the calculation. If the purpose is to assess the effect on the river flow at Trenton, the flow of 3,000 cfs should be the base flow used. For Trenton flows less than 3,000 cfs, withdrawals for Limerick will be made only if compensated gallon for gallon by releases from upstream storage, and there will be no reduction of the Trenton flow. However, if the purpose is to assess the potential for impingement or entrainment, for example, at the Point Pleasant intake, then the percentage calculation should be the river flow at the intake that is equivalent to a Trenton flow of 2,500 cfs. Based on drainage area, the equivalent Point Pleasant flow is 2,425 cfs. This is an interim low flow until scheduled additional storage capacity increases the sustainable flow (modifications of Walter and Prompton Reservoirs to provide water-supply storage.) The occurrence of the low flows in January 1981 have been discussed earlier herein under the heading " Surface water hydrology." In the context of considering the percentage of the Delaware River flow withdrawn for the Limerick project, such low Delaware flows are relevant only if simultaneous with Schuylkill River and Ferkiomen Creek low flows that would trigger a switch from the Schuylkill River, or Perkiomen Creek, as the source of make-up water, to the Delaware River. The Schuylkill flows in January 1981 were too l low to permit make-up withdrawals; the maximum daily flow at Pottstown was only 490 cfs. Also, the flows in the Perkiomen Creek at Graterford were too low to serve Limerick. Therefore, in a recurrence of these circumstances, the Delaware River would be the source of make-up water for the Limerick Station, assuming it was operating. I l
It should be noted that the hydrologic conditions of January 1981 were of ; 1 Concern about low flows like record-breaking rarity for dry winter periods. those of January 1981 should be tempered with recognition of their rarity. As noted elsewhere herein, the Trenton flows below the objective flow l were not indicative of the flow capability of existing reservoirs; the ob-served deficient flows were the result of difficulty experienced by the Delaware River Master in scheduling reservoir releases to meet the flow objectives at Montague. The deficiences could have been made up by releases from lower-basin reservoirs controlled by the DRBC, but in view of the season--with minimum stress on aquatic life--the DRBC deemed it more prudent to conserve water in storage except as needed for controlling salinity in the Delaware estuary. With the 1983 adoption of the rules for reservoir operation (DRBC Res-olution 83-13), the likelihood of future flows less than the objective flows specified in these rules has been reduced. The DRBC will continue to confer with the River Master to encourage the scheduling of releases to meet the specified objectives. In spite of everything, occasional Delaware River flows below the flow objectives cannot be ruled out. If such flow deficiencies occur in the future, withdrawals for Limerick will have varying environmental impacts depending on various factors. These include the seasonal factors, such as water temperature and the cyclic stage of living organisms present. The withdrawal of Delaware River. water at the maximum rate planned would have little or no environmental consequences in January, even assuming Delaware flows as low as 1,900 cfs at Trenton. l 1 Enforcement of withdrawal conditions.--The DOI suggests that the state- ! ment in the DES to the effect that Limerick will not be permitted to withdraw l water from the Delaware River when the flows at Trenton fall below 3,000 cfs 1 is unrealistic. DOI's reason is that the DOI is unaware of a single instance
- when the DRBC has required anyone to stop withdrawing water because of low l
flows at Trenton. ( ! l l
, It should be noted that the DRBC prohibition against the Delaware River withdrawals for Limerick when the Trenton flow is less than 3,000 efs applies only if the withdrawals are not replaced by releases from storage (i.e., from Merrill Creek or an alternative project). PECO is a participant in the pro- , posed Merrill Creek Reservoir project, which is currently being planned to provide such releases from storage. If the Merrill Creek project is built, it will preclude the necessity for curtailing withdrawals from the Delaware for
- the Limerick Station.
As the Secretary of the Interior has been a member of the DRBC since its inception, the DOI should be aware that on two occasions, in the droughts of 1965 and 1980-81, the DRBC invoked its emergency powers to curtail withdrawals j from the Delaware River, especially out-of-basin diversione. With the adop-tion of Resolution 83-13, the DRBC has made it clear that similar restrictions i on withdrawals can be expected in future periods of low flows in the Delaware. Even if the DRBC had not used its power to limit withdrawals in past drought periods, it would not follow that the DRBC would fail to enforce the
- conditions specified for the Limerick withdrawals from the Delaware. Waiving these conditions would require the approval of a majority of the five DRBC members (one of which is the Secretary of the Interior) or their representa-i i
tives. The Limerick project was the first project approved by the DRBC for which water use from the Delaware River was conditioned upon a minimum river flow. This condition was specified in the original approval of Limerick water use in 1973. The fact that there has been no DRBC enforcement of the withdrawal condition means only that there has been no occasion to enforce it--and there will be no such occasion until the Limerick project is completed and operating j during a period of low flow in the Delaware River. l The will of the DRBC to enforce its rules is exemplified by fines that have been levied against violators, some of whom were found to be exceeding the withdrawal licits specified by the DRBC. The DRBC has a record of ( enforcing its rules. 1 vr-- m-r--,- r,r..< y w e,-3.-w,,eer -
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Cumulative impacts of withdrawals.--The DOI erroneously states that cumulative impacts of water withdrawals in the Delaware Basin have been ignored, and suggests discussing the combined effects of over-allocating water in the Basin; diversions of water to New York City and northeastern New Jersey; over pumping ground water; excessive consumptive withdrawals; and the lack of adequate mate-up water storage in the Basin on salinity intrusion in upper Delaware Bay. These factors have not been ignored. All of them, as applicable, have been considered and taken into account in the deliberations leading to the DRBC approval of the Limerick water supply. These factors should not be considered by themselves; they must be--and have been--considered in conjunc-tion with all other relevant factors, including the availability of storage impoundments making releases to offset the out-of-basin diversions, releases from existing storage to offset current consumptive use within the Basin and to control salinity in the estuary; and planned new storage capacity to offset projected increases in consumptive use and to increase the ability to control salinity. Taking all relevant factors into account reveals that the water supplies of the Basin are not currently over-allocated, and scheduled con-struction of new impoundments would offset projected increases in consumptive use to the year 2000. It should be noted that the question of over-allocation of water supplies would be relevant to the decision on issuing an operating license for the Limerick station only if there were no restrictions on the use of water for that station. However, these restrictions fully reflect the expected shortage of water during low-flow periods. For example, when there is a shortage of water in the Delaware River (i.e., when the Trenton flow is less than 3,000 cfs), no diversion will be permitted for the Limerick station unless such diversion is replaced by releases f rom storage. Salinity modeling.-The DOI erroneously states that simulations with the Thatcher-Harleman salinity model of the Delaware estuary have never taken into account the reduced flows from over pumping ground water in consumptive-use l estimates. The salinity model implicitly accounts for ground-water pumpage as l of 1965--the drought year for which the model was calibrated--through the l l t
4 calibration process. The observed fresh-water inflows to the estuary in 1965, which were used in calibrating the model, reflected all ground-water pumping and consumptive use of ground water within the Basin at that time. Post-1965 increases of consumptive use, including consumptive use of both ground and surface water, have been accounted for explicitly by subtracting these consumptive uses from the fresh-water inflows to the Delaware estuary. The DOI erroneously refers to the Potomac-Raritan-Magothy (PRM) aquifer system as an aquifer. It is not a single aquifer, but a group of inter-connected aquifers. The DOI states that the PRM aquifer [ system] underlies the Delaware River south of Camden. This is true, but the PRM system underlies the river north of Camden also, and it is the area upstream of Camden--specifically, upstream of river-mile 98 in Camden--that is considered critical with respect to aquifer recharge by the tidal river. The DOI states correctly that because of heavy pumping of the PRM aquifer system, lowered water tables have caused water f rom the Delaware River to flow into the ground water. This is apparently the basis for the DOI statement earlier in the same paragraph that the salinity model has not taken into account the reduced flows from over pumping ground water, which statement, as explained above, is in error. The DOI assumption that over pumping ground water from the PRM aquifer l system has reduced river flows is subj ect to question and clarification. Much, if not most, of the water pumped from the ground in the vicinity of the tidal Delaware . River, thereby lowering the " water table" (or piezometric surface) of the aquifer system, is not used consumptively, and the nonconsumed water is discharged to the tidal river via waste-water collection and treat-t l ment systems. Thus, much of the aquifer recharge from the river is returned l to the river, and only the consumptive use has to be accounted for in modeling l estuary salinity. As already explained, the consumptive use has been accounted for in the DRBC simulations with the Thatcher-Harleman salinity model.
The DOI states erroneously that the DRBC salinity model assumes a minimun flow of 2,700 cfs. The model has been used to simulate a wide variety of conditions, including regulated dry-season Delaware River flows at Trenton ranging from 2,000 cfs to 4,000 cfs, with year-round variation in accordance with the observed flow regimen. The DOI erroneously states that adequate storage does not now exist in the basin to maintain target flows at Trenton. As explained earlier herein, the DOI is apparently confusing observed flows with sustained-flow capability. The currently existing storage capacity in the Basin is adequate to meet the current target flow. However, to keep ahead of projected increased needs for sustained flows at Trenton, new storage capacity will be needed--and is being planned. The DOI states that the progressive decrease in fresh-water input and rising sea level has resulted in higher salinity levels in Delaware Bay. Al-though there is strong evidence that a rising sea-level trend has contributed to higher salinity in the bay, there is no clear evidence that a progressive decrease in fresh-water input has resulted in significantly higher salinity levels in Delaware Bay in the past. The highest observed salinities in the estuary occurred during the unprecedented severe drought of the 1960s, and resulted from record low fresh-water inputs over an extended period. However, this cannot be classified as a progressive decrease in fresh-water input; it cou.1d have occurred decades earlier under similar drought conditions with similar salinity results, regardless of any other salinity-increasing factor, such as increasing depletive water use. Of course, there has been a progressive decrease in fresh-water inputs to the Delaware estuary, but that decrease was relatively insignificant before the 1965 drought when compared to the natural cycle of runoff, even the avera ge annual cycle, and especially when compared to the great range of fresh-water inputs accompanying floods and droughts. Salinity over seed-oyster beds.--The DOI cited a 1972 study by Dr. Earold H. Haskin, Professor of Zoology and Shellfish Investigations at Rutgers University. This study, according to DOI, showed significant increases in 1
salinity at five locations ' in Delaware Bay over a 41 year period. This 1972 study,- sponsored by the DRBC, was based on empirical correlations between observed antecedant mean 30-day flows of the Delaware River at Trenton and salinity at given locations over seed-oyster beds in the upper bay. The correlations ignored all inputs or subtractions of fresh water seaward of Trenton. This and other shortcomings of such empirical correlations led to i the development of the DRBC (Thatcher-Harleman) mathematical model of salinity distribution in the Delaware estuary. It appears ironic that after criticiz- l ing the DRBC salinity model on the mistaken DOI assumption that it did not l [ account for reduced fresh-water inflows below Trenton resulting from pumping l ground water, the DOI would cite as evidence the Haskin correlations--which did not take into account any fresh-water inputs or subtractions from either surface or underground sources seaward of Trenton. With the availability of the state-of-the-art Thatcher-Harleman salinity model, inconsistencies between the results of the Haskin correlations and those of the DRBC salinity model should be resolved in favor of the latter. The DOI appears to have misinterpreted the results of Dr. Haskin's study. According to the DOI, Dr. Haskin showed significant increases in salinity at five locations in Delaware Bay over a 41 year period. Haskin presented flow-salinity correlations for two time periods: from 1927 through 1952 and from 1953 through 1968. He did report "... a tendency toward increased salinity I with a given river flow." However, that tendency did not hold for the higher I salinities and the corresponding lou river flows; at all five locations studied, the higher salinities for the 1953-1968 period were lower than the pre-1953 salinities for a given river flow. Figure 1, taken from Haskin (1972), clearly shows this phenomenon. Since it is the high salinities that are of concern with respect to oyster protection, the Haskin study results suggest that post-1952 salinity conditions are more favorable to oysters than pre-1953 salinity conditions. This is opposite to the conclusion reached by the DOI from Haskin's report. The principal conclusion reached by Haskin (1972) was that the salinity-flow relationships for the'accond period differ from those of the first period. That is, for a given river flow at Trenton, the salinitics for the two periods differed. .This indicates that some factor other than the river i .
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flow at Trenton had changed from the first period to the second. Haskin stated that the cause of the shift in the salinity-flow relationship was un-known, but suggested three possibilities, as follows:
- 1. A shift in the ratio of fresh-water supply tc the Bay area between sources above and below Trenton.
- 2. Changes in bottom topography in the estuary (by erosion or dredging).
- 3. Changing sea level.
With respect to the first factor, Ebskin stated that if the observed shift is related to a change in fresh-water supply, it would require a reduced fresh-water supply below Trenton for a given river flow at Trenton. This is a correct observation for most of Haskin's data, but, as noted above, his data for low river flows and corresponding high salinities show an opposite shif t in the salinity-flow relationship, which would require an increased fresh-water supply below Trenton for a given river flow at Trenton. It is quite possible, if not probable, that all three factors suggested by Haskin (1972) have contributed to the apparent shift in the salinity-flow relationship for the Delaware estuary. Most of the increase in depletive use within the Delaware Basin has occurred in that part of the Basin below Trenton. There has been channel deepening and other dredging, and sea level has followed a rising trend for many decades. Simulations with the DRBC salinity model have shown that rising sea level significantly increases salinities throughout the Delaware estuary. Another factor, not mentioned by Haskin (1972), that would tend to change the correlations between Trep on flows and Say salinities is modification of the Chesapeake and Delaware Canal. Such modification has been carried out; the canal was enlarged %I. en 1963 and 1975, which overlaps the second period analyzed by Haskin, tr.e 33 through 1968. The partial enlargement by 1968 may have influencea rbswe 's second period results. Recent studies with the DRBC salinity model have shown that the canal generally reduces salinities in _ _ _ - _ _ _ _ _ _ _ _ _ _ _ _ _ _ l
I . s the middle reach of the Delaware estuary, including the upe e portion of
-Delaware Bay. This is consistent with Haskin's observations for low-flow, high-salinity conditions, but not for his observations for high-flow condi-tions when intermediate or low salinities are found over the seed-oyster beds.
Haskin (1972) did not show the dates for which the salinities were observed. The higher salinities are usually observed in late summer or fall of dry years. However, it is the period from May through mid-July that is critical with respect to protection of the seed oysters from enemies that are favored by high salinities. Nothing in the 1972 Haskin report supports any concern that the diver-sion of water from the Delaware River above Trenton for consumptive use at the Limerick generating station would increase salinity over the seed-oyster beds of upper Delaware Bay. In fact, Dr. Haskin has recently responded to allega-tions that the Point . Pleasant diversion would adversely affect the oyster industry of Delaware Bay. In a letter to the Managing Editor of Del-Aware Citizens Voice, a periodical opposing the diversion, Dr. Haskin stated in part:
"You write that the U.S. Fish and Wildlife [ Service] ' report (s) that increased salt in the estuary, is ruining the oyster and shellfish industries,' implying that the Point Pleasant diversion would adversely affect the oyster industry of Delaware Bay. This is incorrect. The New Jersey oyster industry is holding its own despite pressure from predators and MSX problems. Production is rising, and this past year quality has been excellent."
After noting that the critical requirement for protection of the seed oysters is natural river flows from April first into early summer, Dr. Haskin stated further, as follows:
"If you are implying in your comments that the Point Pleasant diversion would cause salinity problems for the oyster industry, this is wrong. The permitted 95 mgd diversion is not all deple-tive use. Roughly 90% of the public water supply returns to the
4 rinn at or above the Schuylkill. If both Limerick plants were op.;ratin g, that would mean a total depletive use of roughly 50 ago (75 cfs). At the critical time of year for the oyster seed beds, average annual Trenton flows are: April, 23,369 cfs; May, 13,730 cfs; and June, 8,011 cfs. A change of 75 cfs would not be
-measurable down on the seeds beds. Furthermore, by the time the fresh wate [from Trenton] reaches the uppermost of the natural oyster seed beds, additional fresh water inflow below Trenton has increased the ratio of water to 1.6 times the Trenton flow, further minimizing the effect of a 75 cfs depletive use upriver."
Rising sea level.-The DOI referred to a 1979 preliminary draf t of a DRBC report on the effect of rising sea level on salinity in the Delaware estuary. The preliminary draf t, as noted by the DOI, indicated a need for more fresh-water input to the estuary to maintain existing salinity regimes in Delaware Bay. The DOI indicated that this need amounted to incremental flow needs of from 3 to 10 cfs per year. Actually, the preliminary draft indicated that a 35 year incremental flow augmentation of 340 cfs would be needed to offset the expected total rise in sea level from 1965 to the year 2000. This was based on preliminary simulations with the salinity model in which tide data were estimated for the last three months of the fif teen-month period simulated. These three moaths were critical because they coincided with the period of peak salinity intrusion. Later, the observed tide data for these three months were obtained and used in a new 15-month simulation, and the results were significantly different. The corrected tide inputs resulted in a finding that, instead of 340 cfs, only 150 cfs would be needed to offset the projected 35 year rise in sea level (Hull and Tortoriello 1983). This amounts to about 4.3 cfs per year, which is the best available estimate; this vs .ue should be used instead of the range of from 3 to 10 cfs given by the DOI. It should be noted that the DRBC projected the year-2000 sea level on the basis of past trends, and the estimated flow-augmentation need to offset the salinity-increasing effect of the rising sea level did not reflect an accelerated sea-level rise that is currently being considered by some inves-tigators. 1
The question of rising sea level would be pertinent to the licensing of the Limerick station only if that station would reduce the critical low flows of fresh water into the estuary. However, the need to consider sea level has been obviated by the DRBC permit for water use at Limerick, which limits the withdrawals for consumptive use from the natural runoff to periods of itelatively high streamflows, when salinity control in the estuary is not critical. Dissolved oxygen in estuary.-The DOI notes that the DRBC water quality model for the Delaware estuary shows a direct relationship between river flows and dissolved oxygen levels in Zone II of the Delaware estuary, which covers the reach from the head of tide at Trenton (river-mile 133.37) to Riverton, N.J. (river-mile 108.40). The DOI states that water withdrawn at Point Pleasant will bypass all but three miles of Zone II, implying that this would lower dissolved oxygen concentrations in Zone II. However, the DRBC permit for Limerick water use requires that when the flows are critically low at Trenton, the withdrawals at Point Pleasant must be replaced gallon for gallon by releases of water from storage. _Therefore, the Point Pleas, ant withdrawals "for Limerick will not reduce the critical low flows (those less than 3,000 cfs) at Trenton. In considering the effect on river flow as related to Zone II oxygen conditions, it is necessary to consider the cumulative net effect of all developments, not just the Limerick withdrawals. Since the drought of the 1960s, the capability of Trenton flow maintenance has been doubled by the construction of new reservoir capacity and the development of operating rules for existing impoundments. Additional reservoir capacity is planned for future development, which will further improve oxygen conditions in Zone II. For example, Merrill Creek Reservoir is being planned as the source of the releases to replace consumptive water use at the Limerick station, as well as at 14 other generating units, some of which are located seaward of Zone II. Therefore, the releases for these seaward stations will augment the low flows through Zone II, thus improving the dissolve-oxygen conditions for the benefit of fish migrating through the upper estuary. This benefit will extend beyond Zone II. k Water quality 4 East Branch Perkiomen.-The DOI expressed concern about potential nuisance algal blooms and plant growth in the East Branch of Perkiomen Creek-because ' of observed orthophosphate concentrations of from 0.01 to 0.75 mg/l in the Delaware River 25 miles upstream of the Point Pleasant intake. The DOI stated that with a short detention time in Bradshaw Reservoir, up to four times the level of organic phosphates could be discharg-ed to the East Branch. The East Branch has an average gradient of about 11 feet per mile, which means that - it is a fast moving stream, especially with a minimum regulated flow of 27 cfs at the control gage near the head of the stream during low-flow + periods. Such rapidly flowing streams are not conducive to nuisance algal blooms or plant growth. During the normal high-flow periods when the minimum flow at the Bucks Road gage will be 10 cfs, temperatures and sunlight are not such as to support nuisance algal or plant conditions. Moreover, the East Branch throughout most of its length already has higher phosphate concentrations than the Delaware River at Point Pleasant. f These high concentrations result from industrial and municipal waste . dis-charges from the Perkasie, Sellersville, and Telford areas, and runoff from farmland and urban areas. As noted in the DES (page 4-31), nutrient levels are excessive in the middle reaches of the East Branch. At the lower East Branch sampling station (E2800), nutrient concentrations remained high, with average phosphate levels about an order of magnitude greater than those of the upper East Branch sampling station. 1-The DRBC staff is of the opinion that the water quality characteristics of the East Branch Perkiomen Creek will be generally improved by the added flow diverted from the Delaware River. This improvement will include a reduc-
- _ti on of average phosphate concentrations in the middle and lower reaches of
- the East Branch. This is especially true for the critical low-flow period of i
l the year, when the augmented flow as measured at the Bucks Road gage will be not less than 27 cfs. l, I
Aquatic resource impact summary The DOI erroneously states that when the Limerick project was originally planned, the DRBC assumed that existing storage capacity was available. The initial DRBC approval of the project recognized the inadequacy of the then existing water-storage capacity, and the approval was conditioned upon the operation of the generating facility only to the extent supported by available streamflow or by future water-supply storage capacity to be developed by the DRBC or--in the absence of DRBC storage--by the applicant. The DOI erroneously states that recent droughts have demonstrated that existing storage capacity cannot even meet current water demands. The fallacy of this statement has been explained earlier herein. Merrill Crcek project.-The DOI recommended that the DES be revised to discuss environmental impacts of the Merrill Creek Reservoir project, which is being planned as a source of water to replace consumptive water losses at the Limerick station and other generating plants. A separate Draft Environmental Impact Statement on the Merrill Creek project has been prepared by the DRBC, and a Final Impact Statement is currently nearing completion. l The rationale for separating the Merrill Creek project from the Point Pleasant diversion for purposes of environmental review and impact-statement preparation is addressed in the Draft EIS for the Merrill Creek project. This issue was addressed by the U. S. District Court in Delaware Water Emergency l l Group et al. v. Gerald M. Hansler, et al. and Neshaminy Water Resources Authority and Philadelphia Electric Company, No. 8-=4372, August 17, 1981. l The Court found that the Merrill Creek Reservoir was "...not required...not an l essential or necessary adjunct. . . " to the Point Pleasant project application. l The environmental issues related to the Merrill Creek project raised by the DOI will be addressed in the Final EIS on that project, to be issued by l l the DRBC. l The DOI recommended that less environmentally damaging make-up water storage options in the Schuylkill River Basin be seriously considered as
alternatives to the Merrill Creek project. Alternatives to the Merrill Creek are discussed in the Draft EIS on the Merrill Creek project, and will be discussed further in the Final EIS being prepared by the DRBC. Unavoidable adverse impacts The DOI states that the DES does not adequately address impacts of the Limerick project on fish and wildlife resources, and that the DES does not reflect the most recent information pertaining to these impacts. The DOI states that the impact assessment of the Point Pleasant diversion relies heavily on data previously prepared by the DRBC, and the DOI believes that assumptions used by the DRBC in the original models to generate these data are no longer valid, based on the most recent information available. The DRBC staff is not aware of any recent information that would change the impact assessment of the Point Pleasant diversion. Perhaps the DOI refer-ence to assumptions used in the DRBC models is based on the DOI's , mistaken assumption that the DRBC salinity model does not account for reduction of fresh-water flow into the estuary caused by ground-water pumping from aquifers hydraulically connected with the estuary. This erroneous DOI assumption has been discussed earlier herein. Water quality in estuary.--The DOI states that the potential exists for cumulative adverse impacts to water quality in the Delaware estuary and for increased salinity intrusion in upper Delaware Bay. The DRBC prohibition against diversion of Delaware River water for use at Limerick when the Dela-ware River flow at Trenton is less than 3,000 cfs adequately protects the general water quality of the Delaware estuary. The DOI concern about increased salinity in upper Delaware Bay has been addressed earlier herein under the heading " Environmental Consequences." Water quality in Perkiomen Creek.-The DOI states that water quality may be degraded in Perkiomen Creek during diversions from the Delaware River. The
,DRBC staff does not believe that Perkiomen Creek water will be degraded by the diversion. We believe that the low-flow au; mentation to be provided by the diversion in both the East Branch and the main stem of Perkiomen Creek will
generally improve the quality of these streams, now degraded by discharges of sewage and industrial wastes and contaminants from non point sources. Entrainment and impingement.-The DOI states that a potential exists for entrainment and impingement of eggs and larval fishes at the Point Pleasant intake. The entrainment and impingement problem has been minimized by relocation and redesign of the intake in accordance with state-of-the-art suggestions by the U. S. Fish and Wildlife Service and the Pennsylvania Fish Commission. Class 9 accident .-The DOI states that the potential for impacts on ground-water resources as a result of a Class-9 accident involving penetration of the basemat by reactor core debris is especially worthy of analysis at the Limerick site, because the Brunswick aquifer is characterized by secondary permeability derived largely from vertical joints, as noted on page 4-22 of the DES. This permeability may permit relatively rapid movement of contamin-ants in ground water in the event of a melt through the basemat and escape of contaminants. Evaluation of Class-9 accidents is the responsibility of NRC, not DRBC. The DRBC staff notes that the DES states in its " Summary and Conclusions" (page viii, subsection 4(s)) that the plant-specific review of the Limerick probabilistic risk assessment analysis of severe accidents is not complete, and that the NRC staff's analysis of the environmental impacts of postulated plant accidents will be provided in a supplement to the DES. On page 5-b, the DES states that the results of the NRC staff evaluation of the environmental impacts of postulated accidents will be published as a supplement to the DES and will be available for public connent. Fish and Wildlife Coordination Act The DOI states, in its letter dated August 26, 1983, that its comments presented therein do not preclude separate evaluation and comments by its subagency, the Fish and Wildlife Service (FWS), pursuant to the Fish and Wildlife Coordination Act (48 Stat. 401, as amended; 16 U.S.C. 661 et seq.), since the proposal to construct the dam and water intake structures will
i 'i
,g require Section 404 permits from the Corps of Engineers. However, the Corps of Engineers had already issued the Section 404 permits for construction of the water intakes well before the Draft Environmental Statement related to operation was issued by the NRC - in June 1983. Moreover, there is no dam requiring a section 404 permit in the Limerick project. Perhaps the DOI is referring to the intake and dam associated with the Merrill Creek Reservoir project, which is a separate project for purposes of environmental review.
As already noted herein, the economic feasibility of the Limerick Cenerating Station does not depend on the Merrill Creek project. Also, the latter project is designed to provide water supply for 14 generating units in addition to Limerick Units 1 and 2, and therefore, the Merrill Creek project would be needed even if not used to supply water for Limerick. Point Pleasant The DOI noted that on October 18, 1982, the Fish and Wildlife Service ! recommended denial of the Department of the Army construction permit to the i Neshaminy Water Resources Authority. However, the permit was subsequently issued, and the permit question was moot at the time of the EDI comments to the NRC in August 1983. The DOI cites several reasons why the FWS recommended denial of the section 404 . permit for the Point Pleasant diversion. This project has been subjected to thorough environmental review by the DRBC and the Corps of ( l Engineers, and the adequacy of these reviews have been affirmed by the U. l l S. District Court. All necessary approval by the DRBC has been granted, and the section 404 permit has also been issued. The DOI's purpose in raising a question ~ pertaining to construction permits for the Point Pleasant diversion in August-1983 is not clear.
' Delaware Bay salinity.-Under the heading of the " Point Pleasant" project, the DOI presents as FWS arguments the same salinity-related comments l
presented earlier in the DOI letter in discussing the Limerick station LES. The validity of these DOI comments has been reviewed already in these DREC staff comments. I
, . . _ , - - . - , . - - . . _ . . - - - _ - - _ ~ _ . . . - . . . . - , . - - - - . - - . . - - .
Estuarine dissolved oxygen.-The arguments related to dissolved oxygen presented by the DOI as FWS reasons for its recommendation for permit denial for the Point Pleasant diversion are essentially the same as the earlier DOI comments on the Limerick station DES. 'Ihe validity of these DOI comments has been reviewed already in this paper. Impacts on North Branch Neshaminy Creek and E~ast Branch Perkiomen Creek.-The DOI presents an FWS allegation that increased discharges to both the North Branch Neshaminy Creek and the East Branch Perkiomen Creek will scour stream banks and stream bottom, increasing turbidity and sedimentation downstream. Only the East Branch Perkiomen Creek is involved in the Limerick application. Both creeks have been considered by the DRBC in its court-approved environmental reviews of the Limerick water supply project and the Neshaminy public water supply system. The NRC DES, on page 5-31, reviews the DRBC conclusions about the environmental impacts of the diversion of Delaware River water (pages 33-35 and 44 of the DRBC EIS of 1973). These court-sanctioned conclusions provide an adequate response to the FWS allegation. Lake Galena.-The DOI presents an FWS allegation that increased phosphate loading of Lake Galena will accelerate eutrophication and cause water quality problems. Lake Galena is not part of the facilities required for supplying water to the Limerick generating station; it is part of the public water-supply system being developed by the Neshaminy Water Resources Authority. The Neshaminy Water Supply System is covered by a separate environmental review. This review has been approved by the Federal courts. Cadmium and lead.--The DOI cites an FWS allegation that Delaware River water diverted to the East Branch Perkiomen Creek and the North Branch Neshaminy Creek will degrade water quality in both streams by introducing higher levels of cadmium and lead. The diversion to the North Branch Neshaminy Creek has been subjected to a separate court-approved environmental review and all permits have been issued.
The FWS concern regarding the introduction of higher levels of cadmium and lead into the East Branch Perkiomen Creek appear to be identical to the DOI concern, to which we have responded earlier herein. Ground-water contamination.--The DOI cites an FWS allegation that the diverted Delaware River water would contaminate ground-water aquifers that are recharged by.Perkiomen Creek. As previously noted herein, the incremental increase in wetted streambed , or hydraulic head caused by augmenting the flow of Perkiomen Creek would be very small, and therefore would not cause a significant increase in the loss of water from Perkiomen Creek to the nearby aquifers. Moreover, the quality of the Delaware River water diverted will be significantly better than the i quality of the water in the middle and lower reaches of the East Branch Perkiomen Creek. Therefore, the quality of the water flowing from the East Branch into the main stem of Perkiomen Creek will be improved by dilution. Aquifers recharged by Perkiomen Creek would receive better quality water from the Creek when the Delaware River water is diluting the contamination that reaches the creek from other sources. Impacts at intake site.--The DOI cites an FUS allegation that the pipeline from the Delaware River to the pumphouse at Point Pleasant will disturb one acre of riverine, forested wetland and permanently destroy 0.3
- acre. ,
This impact was recognized in the environmental review of the Point Pleasant facility, which has been completed and approved by the courts. All permits have been '.ssued and construction is underway. The impact of the pipeline would not be changed significantly if the Limerick praject were not j licensed to operate. Therefore, the impacts of that pipeline on the local area are not relevant to the decision on the Limerick operating license. Delaware River eddy.-The DOI cites an WS concern that the Delaware River intake is at the edge of a large back eddy in the river below Tohickon Creek; and that at low flows the intake will be in this eddy, which is a spawning and nursery area for various species of fish. a_.- - - - - _ - - - _ . . - - - - - - . . - - -
The intake has been reviewed and approved and all necessary permits have been issued based on total diversion rates that include the water supply for limerick, and construction is underway. If the Limerick diversion rate were subtracted from the total approved rate, the hazard to fish eggs and larvae would remain, but would be reduced somewhat. Merrill Creek Reservoir.--The DOI cites an FWS concern that the Merrill Creek Reservoir project, which was partly justified by the Point Pleasant Diversion, would have various impacts on fish and wildlife. The FWS concerns about the Merrill Creek project are being addressed in the Final EIS for that project currently being prepared by the DRBC. Merrill Creek proj ec t.-The DOI, under the heading, "Merrill Creek," states that the FWS recommended denial of a section 404 permit from the Department of the Army for the Merrill Creek project for various reasons. The DRBC is currently preparing the Final EIS for the Merrill Creek project, and the Army permit will not be issued before the EIS is completed. The Merrill Creek project permit is not relevant to the Limerick operating license, as it has been shown to the satisfaction of the Federal courts that the Limerick project would be feasible without the Merrill Creek project. Summary The DRBC staff finds nothing in the DOI comments on the Limerick Gener-ating Station EIS-OL that would justify denial of the operation licenses from the standpoint of water resources. Most of the concerns expressed by the DOI have been considered before in the court-approved environmental reviews of the Neshaminy Water Supply System and the Limerick station water supply by the DRBC. Other DOI concerns relate to the Merrill Creek Reservoir project, which is currently under environmental review by the DRBC and the U. S. Army Corps of Engineers.
References Cited Delaware River Basin Commission. 1973. Environmental Impact Statement, Point Pleasant Diversion Plan, Bucks and Montgomery Counties, Pennsylvania. West Trenton, N.J. Delaware River Basin Commission. 1975. Philadelphia Electric Company-Limerick Nuclear Generating Station, Limerick Township, Montgomery County, Pennsylvania. Docket No. D-69-210 CP (Final), approved November 5, 1975, West Trenton, N.J., 17 pp. Delaware River Basin Commission. 1981. Philadelphia Electric Company-- Bradshaw Reservoir, Pumping Station and Transmission Main, Bucks and Montgomery Counties, Pennsylvania. Docket No. D-79-52CP, approved February 18, 1981. West Trer. con, N.J., 9 pp. Delaware River Basin Commission 1983. Resolution 83-13. A Resolution to Amend the Comprehensive Plan relating to criteria for defining drought warning and drought conditions, and to a schedule of phased reductions in diversions, releases and flow objectives during such periods. Minutes, meeting of June 29, 1983. West Trenton, N.J., 9 pp. [See appendix A, this report.] Haskin, H.H. 1972. Delaware River Flow-Bay Salinity Relationships. Phase III. Report to Delaware River Basin Commission,. Rutgers University, New Brunswick, N.J., 6 pp. Hull, C.H.J., and R. T. Tortoriello. 1983. Sea Level Trend and Salinity in the Delaware Estuary. Staff Paper, Delaware River Basin Commission. Revised May 1983, West Trenton, N.J., 19 pp. Pennsylvania Department of Forests and Waters. 1933. Stream Flow Records for the Four Years: October 1, 1928, to September 30, 1932. Harrisburg, PA. U.S. Geological Survey. 1975. Natural Flow Project, Delaware River Basin. Prepared for Delaware River Basin Commission, Trenton, N.J. U.S. Nuclear Regulatory Commission. 1983. Draft Environmental Statement related to the Operation of Limerick Generating Station, Units 1 and 2-Docket Noc. 50-352 and 50-353--Philadelphia Electric Company. Office of Nuclear Reactor Regulation, Washington, D.C.
E Appendix A Delaware River. Basin Commission Resolution 83-13 A RESOLUTION to amend the Comprehensive Plan relcting to criteria for defining drought warning and drought conditions, and to a schedule of phased reductions in diversions, releases and flow objectives during such periods. WHEREAS, the allowable diversions out of the Delaware River Basin to New York City and northeastern New Jersey, as well as downstream releases from the City's upper basin reservoirs, are prescribed under the provisions of the 1954 amended decree of the United States Supreme Court; and WHEREAS,' the Commission has declared a drought emergency condition on two occasions in 1965 and 1981 pursuant to Section 3.3(a) and Section 10.4 of the Delaware River Basin Compact; and WHEREAS, the adoption of criteria in advance as to what constitutes drought conditions warranting emergency action vill be useful to water users and the general public, as well as to water management officials of the parties; and WHEREAS, the experience during these emergencies has shown the w value of a drought operation formula setting forth diversion rates and ( streamflow objectives for guidance of reservoir ope _ tion; and WHEREAS, the Commission has held public hearings on May 25, June 2, and June 3, 1983 on the proposed criteria and schedul'e recommended by the parties to the amended 1954 decree of the United States Supreme Court, and has received and considered testimony from water users and other interested parties; now therefore,
' BE IT RESOLVED by the Delaware River Basin Commission:
- 1. The Comprehensive Plan and Article 2 of the Water Code of the Delaware River Basin are hereby amended by the addition of new Sections 2.5.3 and 2.5.4 to read as follows:
2.5.3 Schedule of Phased Reductions in Diversions, Releases and Flow Obj ectives During Drought A. Criteria Defining-Conditions For purposes of water management pursuant to Section 3.3 and Article 10 of the Compact, diversions of water from the Delaware River Basin by the City of New York snd State of New Jersey, compensating reservoir releases from the New York City Delaware Basin Reservoirs, reservoir releases from Beltzville Reservoir, Blue Marsh Reservoir, and other reservoirs under the jurisdiction or control of the Commission, and streamflow objectives at the USGS gaging stations located at Montague, New Jersey, and Trenton, New Jersey, shall be governed by a schedule based upon a differentiation among " normal", " drought warning", and " drought" conditions defined by the combined storage in the Cannonsville, Pepacton and Neversink Reservoirs as set forth in Figure 1 entitled " Operation Curves for Cannonsville, Pepacton and Neversink Reservoirs". The division of the drought-warning zone into upper and lower halves shall be defined as a physically equal division, or 20 billions of gallons in each zone. B. Schedule of Reductions The schedules of phased reductions set forth in Tables 1 and 2 shall govern (1) the maximum allowable rates of diversion of waters from the Delaware River Basin by the City of New York and State of New Jersey; (2) the minimum compensating releases to be made by the City of New York from its reservoirs in the upper Delaware Basin; and the streamflow
OPERATION CURVES FOR CANN0NSVILLE, PEPACTON AND NEVERSINK RESERVOIRS 280 271 260 240 220 200 7e 180
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- In Diversions, Releases, and Flow Objectives During Periods of Drought Montague Trenton NYC Storage NYC Div. NJ Div. Flow Objective Flow Objective Condition 'mgd mgd efs cfs Normal 800 100 1750 3000 Upper Half--
Drought Warning 680 85 1655 2700 Lower Half-- Drought Warning 560 70 1550 2700 Drought 520 65 1100-1650* 2500-2900* Severe Drought (to be negotiated based on conditions)
- Varies with time of year and location of salt front as shown on Table 2.
TABLE 2 l Flow Objectives for Salinity Control i During Drought Periods Seven-day Average Location of Flow Objective, Cubic Feet Per Second At:
" Salt Front," Montague, N.J. Trenton, N.J.
River-mile
- Dec-Apr May-Aug Sept-Nov Dec-Apr May-Aug Sect-Nov
, Upstream of R.M. 92.5 1600 1650 1650 2700 2900 2900 Between R.M. 87.0 and R.M. 92.5 1350 1600 1500 2700 2700 2700 Between R.M. 82.9 and R.M. 87.0 1350 1600 1500 2500 2500 2500 Downstream of R.M. 82.9 1100 1100 1100 2500 2500 2500
- Measured in statute miles along the navigation channel from the mouth of Delaware Bay.
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0 objectives at the USGS gaging stations located at Montague, New Jersey and Trenton, New Jersey. During " drought" conditions as defined by Figure 1, the streamflow objectives at the Montague and Trenton gaging stations shall be established as set forth in Table 2, in accordance with the seven-day average location of the 250 mg/l isochlor (the " salt front") in the Delaware Estuary. C. Diversion Allowances and Release Requirements (1) The City of New York may divert waters from the Delaware Basin at maximum rates equivalent to the quantities set forth in Table 1. (2) The State of New Jersey may divert waters from the Delaware River Basin, from the Delaware River or its tributaries in New Jersey, at maximum rates equivalent to the quantities set forth in Table 1. (3) The City of New York shall release water from one or more of its storage reservoirs in the upper Delaware Basin in quantities designed to maintain the minimum basic rates of flow at the USGS gaging station located at Montague, New Jersey, as set forth in Tables 1 and 2. D. Computation of Diversions (1) Diversions by the City of New York during " normal" conditions, as defined by Figure 1, shall be computed as provided in Section III.A.4. of the Amended Decree of the U. S. Supreme Court in New Jersey v. New York, 347 U.S. 995 (1954). At no time during'a twelve-month period of the Water Year, commencing June 1, shall the aggregate total quantity diverted by the City of New York, divided by the number of days elapsed since the preceding May 31, exceed the maximum permitted rate of diversion.
&, 9 (2) Diversions by the State of New Jersey during " normal" periods, as defined by Figure 1, shall be computed as provided in Section V.B.of the amended Decree of the U.S. Supreme Court in New Jersey
- v. New York, 347 U.S. 995 (1954). The total diversion by the State of New Jersey shall not exceed an average of 100 mgd as a monthly average, with the diversion on any day not to exceed 120 million gallons, and its total diversion without compensating releases shall not exceed 100 mgd'during any calendar year.
(3) Diversions by the City of New York and State of New Jersey set forth in Table 1 during " drought warning" and " drought" conditions as defined by Figure 1, shall be computed as a daily running average, commencing on the day such drought warning or drought operations become effective, as provided in subsection E of this Section. If the allowable diversion for any condition period following entry into drought warning operations is not fully used, the unused portion may not be credited or used during subsequent periods. (4) Upon return to normal condition operations, following a period of drought warning or drought operations, diversions by the City of New York and State of New Jersey shall be computed as averages commencing upon the date of return to normal operations. E. Effective Period for Drought Operating Schedule (1) The schedule of diversions, releases and streamflow objectives for " drought warning" operations as provided in Subsection B shall go inte effect automatically whenever the combined storage in the New York City Delaware Basin Reservoirs declines below the drought
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a' ' F 6 warning line, defined in Figure 1 and remains below that line for five consecutive days. (2) The schedule of diversions, releases and strcamflow objectives
-for " drought" operations as provided in Subsection B shall go into effect immediately whenever the combined storage in the New York City Delaware Basin reservoirs declines below the drought line defined in Figure 1, and remains below that line for five consecutive days.
(3) Whet. the combined storage in the New York City Delaware Basin reservoirs (including the projected water runoff equivalent of actual snow and ice within the watersheds tributary to the reservoirs) reaches a level 15 billion gallons above the drought warning line, as defined in Figure 1, and remains above that level for five consecutive days, the drought warning and drought operations schedules set forth in Subsection B shall automatically terminate, and normal operations shall be resumed as provided in the Amended Decree of the D. 3. Supreme Court in New Jersey v. New York, 347 U.S. 995 (1954). (4) Pursuant to Section 3.3(a) of the Compact, the Parties to the U. S. Supreme Court Decree in New Jersey v. New York, 347 U.S. 995 (1954), have given their unanimous consent to adoption and implementation by the Commission of the drought operation schedules provided in this section. The Parties have agreed that the drought operation formula will go into effect automatically, and be binding on parties for not less than 180 days following the' triggering of drought warning operations, unless terminated automatically by improved storage conditions as provided in Subsection E.3. During the 180-day period following triggering of drought warning operations, authorized representatives of the City of
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New York, States of Delaware, New Jersey, and New York, and Commonwealth of Pennsylvania, as parties to the U. S. Supreme Court Decree, shall convene no less frequently than once each month to review current condi-tions, and they may extend, modify, or extend as modified the schedules provided in this section. If no unanimous agreement as to a continuing drought operation formula is reached within the 180-day period, all Parties shall be released from the terms of the formula and schedules and may pursue their rights and obligations under the Delaware River Basin Compact and the U. S. Supreme Court Decree. 2.5.4 Drought Emergency Actions A. Criteria Defining Conditions For purposes of water management pursuant to Section 3.3 and Article 10 of the Compact, the determination of drought warning and drought conditions shall be based "pon the combined storage in the Cannonsville, Pepacton and Neversink. Reservoirs, in accordance with Figure 1, entitled " Operation Curves for Cannonsv111e, Pepacton and Neversink Reservoirs". The division of the drought-warning zone into upper and lower halves shall be defined as a physically equal division, or 20 billions of gallons in each zone. B. Drought Emergency Declaration It is the policy of the Commission that a drought emergency will be declared for purposes of imposing mandatory in-basin conservation measures and other appropriate actions whenever combined storage in the New York City Delaware Basin reservoirs falls into the drought zone as defined in Figure 1 for five consecutive days. Termination of a drought emergency will be considered by the Commission whenever combined storage in the New York City Delaware Basin reservoirs reaches a level 40 billion
, , .. ? s gallons above the drought warning line as defined in Figure 1 and remains above that line for 30 consecutive days. The drought emergency will be terminated by the Commission whenever the combined storage in the New York City Delaware Basin reservoirs reaches 40 billion gallons above the drought warning line defined in Figure 1 and remains above that line for 60 consecutive days, unless the Commission unanimously agrees to extend the emergency. Ef fect of Policy This policy is not intended to extend, impair, or conflict with the 4 Commission's authority under the Lompact to declare or terminate a drought emergency or water-shortage emergency in the Basin, or subregion thereof, in other instances as conditions may require.
/s/ R. Timothy Weston R. Timothy Weston, Chairman pro tem
/s/ Susan M. Weisman Susan M. Weisman, Secretary ADOPTED: June 29, 1983 4
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