1/22/1988 CONSERVATION COMMISSION Minutes

Home Browse Search

i .#drainage Easement January -26, 1988 a i Page PHYLLIS P KD � : Sped fical +, .: t 'the time f the tests, were they. eared to d i f fear ent weather con i t i ons B � In al l o , where monitoring well 51is located, the depth of. the 5 well cluster-, the rainfall intensity a day or -two beforehand wo I d have very 1it e impact, if any , because you are t I king a =numb-er' of hundred' f 'eV.d wn- radient from th'e base itself and the ground - Water around ' the base percolates into the soil around l to 1-1./2 feet- per day: .HARK ROBINSON, CAPE COD PLANNING COMMISSION: He asked the'-Colonel t o describe the oil/water separators and speak about the ma-intenance, monthly or yearly. PD : The day to day operation he would refer' to.-Mr. Duggan. The oil water separator was instal-led in 1969* We- have a.. -project being designed a consulting' firs to address a e o-0 l/water epar� tr� . on the base to modernize and upgrade them.- .We will have. 1987-198 - tech- nology in a short period of time. What we- have`- herenow is- the basic requirement of the Air Force and Dept, of.' Defense back in. the ' 60' s. - DICK : It is an ind stri l oil/water, separatdr. Water . crimes in and flows' into 4 separatechambers. The wader that goes into- the chii- ber Is rciguilated. Once into the chambers, oil , .fuel or any .otherobnox- ious brio -- ious material will float onto thesur•face.' The water- ei-ts the- chamber by vertical pipes at the other end set 'at the level of the water bt -are down to the bottom of the water in the chambers, about 6 feet ' th i c-k, abd that -water 'comes out - all clear' ; s more water comes in, it Jlows .doWn, It. flows -down through a -channel and' then out into the prop- osed a ement. In the middle of this is an oil chamber and across each i= of the individual chambers there areutomatic skimmers that take uta to 6 inches of o i l o f f of he surface which drains' into the o i l cham- ber. .- Approximately every three months, hese oil chambers are pumped out and we pump out roughly 610 gallons of water and oil mixed. HARK ROBINSONS is this a system where it fills up wi.th - water and is then pumped out. D : leo, the skimmer skims -it off into- the chamber ROBINSON: But ghat kind of pump, ,i. - i t a Scavenger Pump? D N: In the chamber i tse�l f', we gust. go in ori t a' hose on .a truck, lower it into the oil- chamber and dump i t out s There used to be pumps o�n, but they were found 'to be c'u bersome . and -were removed. The daterthat - comes out of these individual chambers -We tested twice a cou le of years ago f'or volatile organic compounds and there was no trace any material in any orae. They will now do -testing every quarter. In the re- pair -pair project, we are going- in' 'to repair the skimmers, the engineering firm h-as recommended that we -put o i'l subnater i al s in front of the skimmers. MARK D INSON: .Has there been any attempt to ._ 100 k at the use of re- charge basins or retention basins along the length of the drainage ditch to acc.umulate .some of the water and to 'reduce- the flow. DCS is The flow is reduced prior to _r oing. into the -chamber; there is small , impounding basin so if flow does get excessive going into the climber, it can beholed -up in this impounding basin. :.